[ { "id": "https://authors.library.caltech.edu/records/qnfp7-zw840", "eprint_id": 91385, "eprint_status": "archive", "datestamp": "2023-08-19 12:27:49", "lastmod": "2024-01-14 21:14:22", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taghavi-Larigani-S", "name": { "family": "Taghavi Larigani", "given": "Shervin" }, "orcid": "0000-0002-6599-7855" }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Can We Measure Deformation of Short and Stiff Bridges as Trucks Traverse Using a Camera?", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2018 The Authors. \n\nThis is a collaboration with STL-Scientific and Caltech Earthquake Engineering Laboratory.\n\n
Accepted Version - final_video.mp4
", "abstract": "[no abstract]", "date": "2018-12-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2018-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2018-03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "final_video.mp4", "url": "https://authors.library.caltech.edu/records/qnfp7-zw840/files/final_video.mp4" }, "pub_year": "2018", "author_list": "Taghavi Larigani, Shervin and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/qe307-yv175", "eprint_id": 86943, "eprint_status": "archive", "datestamp": "2023-08-19 09:27:51", "lastmod": "2024-01-14 20:14:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taghavi-Larigani-S", "name": { "family": "Taghavi Larigani", "given": "Shervin" }, "orcid": "0000-0002-6599-7855" }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "WeighCam: a New Electro-Optical System", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2018 The Authors. \n\nThis is a collaboration with STL-Scientific and Caltech Earthquake Engineering Laboratory.\n\nSubmitted - WeighCam.mp4
", "abstract": "[no abstract]", "date": "2018-06-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2018-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2018-02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "WeighCam.mp4", "url": "https://authors.library.caltech.edu/records/qe307-yv175/files/WeighCam.mp4" }, "pub_year": "2018", "author_list": "Taghavi Larigani, Shervin and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/jq43r-40k43", "eprint_id": 85876, "eprint_status": "archive", "datestamp": "2023-08-19 08:06:40", "lastmod": "2024-01-14 19:35:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-J-F", "name": { "family": "Hall", "given": "John F." }, "orcid": "0000-0002-7863-5060" } ] }, "title": "Performance of Viscous Damping in Inelastic Seismic Analysis of Moment-Frame Buildings", "ispublished": "unpub", "full_text_status": "public", "note": "Updated - DampingReportUpdated2.pdf
", "abstract": "This report investigates the performance of several viscous damping formulations in the inelastic seismic response of moment-frame buildings. The evaluation employs a detailed model of a 20-story steel building. Damping schemes included in the study are Rayleigh, condensed Rayleigh, Wilson-Penzien, two versions of tangent Rayleigh and one implementation of capped damping. Caughey damping is found not to be computationally viable. Differences among the damping schemes, as quantified by amounts of plastic hinge rotations and story drifts, become noticeable once these quantities reach the 3% level. In order of least to greatest hinge rotations and drifts that occur under lateral response to horizontal ground motion, the damping schemes rank as Rayleigh (most damping action), condensed Rayleigh, Wilson-Penzien, the standard form of tangent Rayleigh and capped damping, which are about the same, and the elastic velocity version of tangent Rayleigh (least damping action). Performance of Rayleigh damping under vertical ground motion is discussed, including the effect of soil-structure interaction. The propensity of Rayleigh damping to generate excessive damping forces and moments during inelastic seismic analysis is explained, and a parameter is introduced that can predict the potential magnitude of the effect. A review of some literature on the role of viscous damping on the inelastic seismic response of moment frames is also presented.", "date": "2018-04-16", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20180416-115953567", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180416-115953567", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "DampingReportUpdated2.pdf", "url": "https://authors.library.caltech.edu/records/jq43r-40k43/files/DampingReportUpdated2.pdf" }, "pub_year": "2018", "author_list": "Hall, John F." }, { "id": "https://authors.library.caltech.edu/records/scwxv-rf070", "eprint_id": 78132, "eprint_status": "archive", "datestamp": "2023-08-19 03:20:47", "lastmod": "2024-01-13 20:28:15", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taghavi-Larigani-S", "name": { "family": "Taghavi Larigani", "given": "Shervin" }, "orcid": "0000-0002-6599-7855" }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Can we measure deformation of short and stiff bridges when a train passes over using a camera?", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2017 The Authors. \n\nThis is a collaboration with STL-Scientific.\n\nSubmitted - video.mp4
", "abstract": "[no abstract]", "date": "2017-06-13", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2017-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2017-02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "video.mp4", "url": "https://authors.library.caltech.edu/records/scwxv-rf070/files/video.mp4" }, "pub_year": "2017", "author_list": "Taghavi Larigani, Shervin and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/mqfby-3kh57", "eprint_id": 73902, "eprint_status": "archive", "datestamp": "2023-08-19 01:12:15", "lastmod": "2024-01-13 20:24:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taghavi-Larigani-S", "name": { "family": "Taghavi Larigani", "given": "Shervin" }, "orcid": "0000-0002-6599-7855" }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Can you measure the weight of a truck with a commercial camera?", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2017 The Authors. \n\nThis is a collaboration with STL-Scientific.\n\nSubmitted - s_taghavil_t_heaton_2017.mp4
", "abstract": "[No abstract]", "date": "2017-02-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2017-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2017-01", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "s_taghavil_t_heaton_2017.mp4", "url": "https://authors.library.caltech.edu/records/mqfby-3kh57/files/s_taghavil_t_heaton_2017.mp4" }, "pub_year": "2017", "author_list": "Taghavi Larigani, Shervin and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/f86wq-79a02", "eprint_id": 72248, "eprint_status": "archive", "datestamp": "2023-08-22 14:23:49", "lastmod": "2024-01-13 20:20:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Ming-Hei", "name": { "family": "Cheng", "given": "Ming Hei" } }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" }, { "id": "Kohler-M-D", "name": { "family": "Kohler", "given": "Monica D." } } ] }, "title": "Interpretation of Millikan Library's Vibrating Modes Using A Magneto Coil To Measure Phase Shifts", "ispublished": "unpub", "full_text_status": "public", "keywords": "Millikan Library; natural frequency; phase shift; magneto coil; subspace system identification", "note": "This work is partially supported by the National Science Foundation (EAR-1027790), George Housner Earthquake Engineering Research Endowment (EAS-41212), Fred L. Hartley Family Foundation, and Croucher Foundation. Their support is gratefully acknowledged.\n\nSubmitted - EERL2014-02_-_Cheng.pdf
", "abstract": "A new set of natural frequencies for the 9-story reinforced concrete Millikan Library building on the Caltech campus is computed using the observed phase shift between the driving force of a shaker installed on the building's roof and structural response at resonance. The phase of the shaker's output force was recorded by a magneto coil and magnet attached to the shaker's rotating mechanism, and the phase of the structural response was obtained from acceleration time series recorded by an accelerometer on the roof. These new results refute previous studies' identification of the 3rd EW and 2nd torsional modes which used spectral analysis of forced and free vibrations, but did not consider the phase shift. In addition, the newly identified 3rd EW mode shape is independent of the other EW mode shapes, unlike previous findings. This new interpretation is compatible with results from subspace system identification based on two sets of earthquake records.", "date": "2016-11-22", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechAUTHORS:20161122-122249021", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161122-122249021", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1027790" }, { "agency": "George Housner Earthquake Engineering Research Endowment", "grant_number": "EAS-41212" }, { "agency": "Fred L. Hartley Family Foundation" }, { "agency": "Croucher Foundation" } ] }, "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.7907/Z9H70CS4", "primary_object": { "basename": "EERL2014-02_-_Cheng.pdf", "url": "https://authors.library.caltech.edu/records/f86wq-79a02/files/EERL2014-02_-_Cheng.pdf" }, "pub_year": "2016", "author_list": "Cheng, Ming Hei; Heaton, Thomas H.; et el." }, { "id": "https://authors.library.caltech.edu/records/f3a20-t7d53", "eprint_id": 69232, "eprint_status": "archive", "datestamp": "2023-08-20 12:57:50", "lastmod": "2024-01-13 16:52:45", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taghavi-Larigani-S", "name": { "family": "Taghavi Larigani", "given": "Shervin" }, "orcid": "0000-0002-6599-7855" }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Characterizing Deformation of Buildings from Videos", "ispublished": "unpub", "full_text_status": "public", "note": "The authors are thankful to Anthony Massari for providing ETABS generated data pertaining to JPL/NASA building 180 dynamics. \n\nShervin Taghavi Larigani is grateful to Mr Micheal David Donohoe (STL-Scientific), and thanks Dr Jakob Vanzyl (Caltech & NASA/JPL), Prof Michael Hoffmann (Caltech), Prof Mark Simons (Caltech), Prof Luis Rivera (Caltech & Institut de Physique du Globe de Strasbourg), Prof James Rice (Harvard University), Mr B. Afshar, Dr Renaud Goullioud (JPL/NASA), Mr A. Gerber (JPL/NASA), Colonel B. Cox (USAF ret & JPL/NASA), Prof Christopher Boxe (City University of New York), Prof Guruswami Ravichandran (Caltech), Dr Thomas Ader (Caltech), Mr J. Kelin, Dr Andrea Donnellan (JPL/NASA), Major F. Nassirkhani (IIAF pilot ret), Prof Andrew Ingersoll (Caltech), Prof Yuk Yung (Caltech), Dr Ramses Mourhatch (JPL/NASA), Prof John Baldeschwieler (Caltech emeritus), Dr Ken Pickar (Caltech), Mr R. Stuchter (Programmed Scientific Instruments) and last but not least Mr Sang Chung (JPL/NASA) for their fruitful conversations and help.\n\nSubmitted - TaghaviLarigani_Heaton_final.pdf
", "abstract": "We have started to explore the feasibility of extracting useful data on the deformation of buildings and structures based on optical videos, (Taghavi Larigani & Heaton). \n\nIn the beginning, we look at the characterizations and limitations of the hardware, which is composed of a high-quality digital camera, combined with its optical imaging system capturing a video-footage of the structure under test, and then introduce a straightforward targets-tracking algorithm that produces the time-series displacements of targets that we select on the video. \n\nWe performed preliminary measurements consisting of testing our targets-tracking algorithm using high definition format videos displaying the structures that we wanted to test. The measurements pertain to a 1) finite-element software-generated video of JPL/NASA principal building, 2) YouTube-video of a seismic dynamic test of a building, 3) YouTube-video of the Millennium London Bridge \"Wobbly Bridge\", 4) YouTube-video of a United Boeing 777, 4) YouTube-video of NASA space shuttle rockets during launch. \n\nSo far, our tests are encouraging. If our approach proves viable, it can be transformative for the field of earthquake engineering and structural health monitoring. Hence, we consider the prospect of using our technique for surveying buildings and other civil structures in high seismic risk urban agglomerations. \n\nIn parallel, the same technique could be applied for 1) real-time structural health monitoring of civil structures, 2) nuclear plants, 3) oil and gas infrastructures, 4) rail & road networks, 5) aircraft, 6) spacecraft, 7) etc., by simply analyzing the structure-facing camera recorded data.", "date": "2016-07-27", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20160726-154041262", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160726-154041262", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "TaghaviLarigani_Heaton_final.pdf", "url": "https://authors.library.caltech.edu/records/f3a20-t7d53/files/TaghaviLarigani_Heaton_final.pdf" }, "pub_year": "2016", "author_list": "Taghavi Larigani, Shervin and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/9cc84-ht018", "eprint_id": 58095, "eprint_status": "archive", "datestamp": "2023-08-20 00:29:54", "lastmod": "2024-01-13 16:21:15", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cua-Georgia-B", "name": { "family": "Cua", "given": "Georgia" } }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "Thomas H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Characterizing Average Properties of Southern California Ground Motion Amplitudes and Envelopes", "ispublished": "unpub", "full_text_status": "public", "note": "We wish to thank David Boore and Kenneth Campbell for providing and answering questions about their NGA models, Julian Bommer for providing preprints of his manuscripts, David Wald for interesting and informative discussions on attenuation relationships and help with the ShakeMap codes, and Egill Hauksson for the extensive use of his computers for running the neighborhood algorithm inversions. We also wish to thank John Clinton for his suggestions on improving early versions of the manuscript. \n\nThis work was supported at various stages by the George W. Housner Fellowship at the California Institute of Technology, the Puerto Rico Strong Motion Program, and the Swiss Seismological Service at the Swiss Federal Institute of Technology (ETH Zurich).\n\nSubmitted - EERL2009-05.pdf
", "abstract": "We examine ground motion envelopes of horizontal and vertical acceleration, velocity, and filtered displacement recorded within 200 km from southern California earthquakes in the magnitude range 2 < M \u2264 7.3. We introduce a parameterization that decomposes the observed ground motion envelope into P-wavetrain, S-wavetrain, and ambient noise envelopes. The shape of the body wave envelopes as a function of time is further parameterized by a rise time, a duration, a constant amplitude, and 2 coda decay parameters. Each observed ground motion envelope can thus be described by 11 envelope parameters. We fit this parameterization to 30,000 observed ground motion time histories, and develop attenuation relationships describing the magnitude, distance, and site dependence of these 11 envelope parameters. We use these relationships to study 1) magnitude-dependent saturation of peak amplitudes on rock and soil sites for peak ground acceleration, peak ground velocity, and peak filtered displacement, 2) magnitude and distance scaling of P- and S-waves, and 3) the reduction of uncertainty in predicted ground motions due to the application of site-specific station corrections. We develop extended magnitude range attenuation relationships for PGA and PGV valid over the magnitude range 2 < M < 8 by supplementing our dataset of S-wave envelope amplitudes with the Next Generation Attenuation (NGA) strong motion dataset. We compare extended magnitude range attenuation relationships with the Campbell and Bozorgnia (2008) and Boore and Atkinson (2008) NGA relationships. Our extended magnitude range attenuation relationships exhibit a stronger inter-dependence between distance and magnitude scaling. This character of ground motion scaling becomes evident when examining ground motion amplitudes over an extended magnitude range, but is not apparent when considering data within a more limited magnitude range, for instance, the M>5 range typically considered for strong motion attenuation relationships.", "date": "2015-06-09", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2009-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2009-05", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "George W. Housner Fellowship" }, { "agency": "Puerto Rico Strong Motion Program" }, { "agency": "Swiss Seismological Service" } ] }, "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "EERL2009-05.pdf", "url": "https://authors.library.caltech.edu/records/9cc84-ht018/files/EERL2009-05.pdf" }, "pub_year": "2015", "author_list": "Cua, Georgia and Heaton, Thomas H." }, { "id": "https://authors.library.caltech.edu/records/e1vc3-5wd39", "eprint_id": 29444, "eprint_status": "archive", "datestamp": "2023-08-19 06:52:54", "lastmod": "2024-01-13 05:51:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alimoradi-Arzhang", "name": { "family": "Alimoradi", "given": "Arzhang" } } ] }, "title": "Earthquake Ground Motion Simulation using Novel Machine Learning Tools", "ispublished": "unpub", "full_text_status": "public", "note": "A research report for the Earthquake Hazards Reduction Professional Fellowship Program supported by the Earthquake Engineering Research Institute, the Federal Emergency Management Agency, and the California Institute of Technology under the supervision of Professor James L. Beck.\n\nSubmitted - EERL_Arzhang.pdf
", "abstract": "A novel method of model-independent probabilistic seismic hazard analysis(PSHA) and ground motion simulation is presented and verified using previously recorded data and machine learning. The concept of \"eigenquakes\" is introduced as an orthonormal set of basis vectors that represent characteristic earthquake records in a large database. Our proposed procedure consists of three phases, (1) estimation of the anticipated level of shaking for a scenario earthquake at a site using Gaussian Process regression, (2) extraction of the eigenquakes from Principal Component Analysis (PCA) of data, and (3) optimal combination of the eigenquakes to generate time-series of ground acceleration with spectral ordinates obtained in phase (1). The benefits of using a model-independent method of PSHA and ground motion simulation, particularly in large urban areas where dense instrumentation is available or expected, are argued. The effectiveness of the proposed methodology is exhibited using eight scenario examples for downtown areas of Los Angeles and San Francisco where it is shown that no dependency on specific ground motion prediction equations or processes of selection and scaling would be needed in our procedure. Furthermore, PCA allows systematic analysis of large databases of ground motion records that are otherwise very difficult to handle by conventional methods of data analysis. Advantages, disadvantages, and future research needs are highlighted at the end.", "date": "2012-02-23", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2011-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2011-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format", "funders": { "items": [ { "agency": "Earthquake Engineeeing Research Institute" }, { "agency": "Federal Emergency Management Agency" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_Arzhang.pdf", "url": "https://authors.library.caltech.edu/records/e1vc3-5wd39/files/EERL_Arzhang.pdf" }, "pub_year": "2012", "author_list": "Alimoradi, Arzhang" }, { "id": "https://authors.library.caltech.edu/records/8spmb-x5x69", "eprint_id": 26571, "eprint_status": "archive", "datestamp": "2023-08-19 06:14:43", "lastmod": "2024-01-13 05:32:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" }, { "id": "Muto-Matthew-M", "name": { "family": "Muto", "given": "Matthew" } } ] }, "title": "Mechanism of Collapse, Sensitivity to Ground Motion Features, and Rapid Estimation of the Response of Tall Steel Moment Frame Buildings to Earthquake Excitation", "ispublished": "unpub", "full_text_status": "public", "abstract": "This study explores the behavior of two tall steel moment frame buildings and their variants under strong\nearthquake ground shaking through parametric analysis using idealized ground motion waveforms. Both\nfracture-susceptible as well as perfect-connection conditions are investigated. Ground motion velocity waveforms are parameterized using triangular (sawtooth-like) wave-trains with a characteristic period (T), amplitude(peak ground velocity, PGV ), and duration (number of cycles, N). This idealized representation\nhas the desirable feature that the response of the target buildings under the idealized waveforms closely\nmimics their response under the emulated true ground motion waveforms. A suite of nonlinear analyses are\nperformed on four tall building models subjected to these idealized wave-trains, with T varying from 0.5s\nto 6.0s, PGV varying from 0.125 m/s to 2.5 m/s, and N taking the values of 1 to 5, and 10. This range\nof parameters should be adequate to characterize the ground motions that can be expected to occur during\nearthquakes in the 6-8 magnitude range at some distance (say, > 2km) away from the fault. Databases of\npeak transient and residual interstory drift ratio (IDR), and permanent roof drift are created for each model.\nThe sensitivity of structural response to T, PGV , and N is studied. Severe dynamic response is induced\nonly in the long-period, large-amplitude excitation regime. Through a simple examination of the energy\nbalance during earthquake shaking, it can be shown that the input excitation energy is small for excitation\nwith periods shorter than the structural period, whereas it is proportional to the square of the ground velocity\nif the excitation periods are much longer than the structural periods. Thus, collapse-level response\ncan be induced only by long-period, moderate to large PGV ground excitation. The collapse initiation\nregime expands to lower ground motion periods and amplitudes with increasing number of ground motion\ncycles. It should be noted that the energy balance analysis is not appropriate for excitation velocities that are\nextreme where conservation of momentum may be more applicable. However, peak ground velocity from\nearthquakes seldom exceeds 2.5m/s and energy balance would generally be applicable.\nThe close examination of one instance of collapse shows damage (yielding and/or fracture) localizing\nin a few stories in the form of a \"quasi-shear\" band (QSB) comprising of plastic hinges at the top of all\ncolumns in the uppermost story of the band, at the bottom of all columns in the lowermost story of the\nband, and at both ends of all beams in the intermediate stories. Such a pattern of hinging results in shear-like\ndeformation in these stories, resembling plastic shear bands in ductile solids. Most of the lateral deformation\ndue to seismic shaking is concentrated in this band. When the overturning 1st-order and 2nd-order (P -\n) moments from the inertia of the overriding block of stories exceed the moment-carrying capacity of\nthe quasi-shear band, it loses stability and collapses. This initiates gravity-driven progressive collapse of\nthe overriding block of stories. Thus, the collapse mechanism initiates as a sidesway mechanism that is\ntaken over by gravity once the quasi-shear band is destabilized. There are Ns(Ns+1)\n2 possible quasi-shear\nbands (and an equal number of sidesway collapse mechanisms) in either principal direction of an Ns-story\nmoment frame building. More than one quasi-shear bands could occur during the entire duration of strong\nearthquake shaking. The band exhibiting the greatest distress (termed the \"primary\" quasi-shear band)\niv ultimately evolves into a sidesway collapse mechanism.\nThe formation of the quasi-shear band under single-cycle excitations is explained through the classical\nuniform shear-beam analogy to moment frame buildings. Under low-intensity motions (PGV < 0.25m/s)with periods in the 0.5s-6s range excitation energy is low. As a result, structural response is predominantly elastic and is analogous to that of a uniform elastic shear-beam through which a shear wave propagates. For moderate-intensity excitations (0.25m/s PGV < 1.5m/s), the reverse phase of the incident pulse constructively interferes with the reflected forward phase causing yielding in the region of positive interference,very similar to what would occur in a uniform inelastic shear-beam. The primary quasi-shear band migrates down the building with increasing pulse period. However, this migration slows down with increasing period\nand gets arrested nominally between floors 3 and 9 for the existing building, and between floors 3 and 8\nfor the redesigned building, whereas the peak strain in the corresponding inelastic uniform shear-beam continues\nto migrate to the very bottom. This is a direct result of the non-uniformity of the buildings. Going from the top of the building to the bottom, there is a gradual increase in the strength and stiffness of the structure. The increased strength at the bottom does not allow yielding to permeate into those stories. Now,excitation energy imparted to the structure can be large enough only under long-period ground motion in the context of the target buildings. Therefore, collapse-level response must be accompanied by the formation of the primary quasi-shear band in the vicinity of the stories where the downward migration of the QSB (with\nincreasing T) is arrested.\nFor high-intensity excitations (PGV > 1.5m/s) that are sufficiently long-period, the pulse may yield\nthe structure on its way up the building. The strength of the building drops as the pulse travels up the\nbuilding. However, inertial forces drop as well, as a result of fewer stories above contributing to the mass.\nThe narrow band of stories with an optimal combination of low-enough strength and high-enough inertial\nforce demand is where peak yielding occurs. This region is identical to the region where the downward\nmigration of the primary quasi-shear band is arrested under moderate-intensity, long-period excitation. This\nis because the governing factor dictating the location of the band in both cases is strength non-uniformity. As\nthe wave travels up the building, it is reflected off the roof with a change in sign. Because the period of the\nincident wave is sufficiently long (a necessary condition for large input excitation energy), the reverse phase\nof the incident pulse constructively interferes with the reflected forward phase causing greatest yielding\nin the same region as the pre-reflection yielding. To summarize, under both moderate-intensity and highintensity\nground motions, input excitation energy large enough to collapse the building requires long-period\nexcitation. Such long-period excitation always causes the formation of the primary quasi-shear band in an\noptimal set of stories governed by the mass and strength distribution of the building over its height, which are\ncharacteristics solely of the structure and not the ground motion. When T and PGV are large enough, it is\nthis band that evolves into a collapse mechanism. This points to the existence of a \"characteristic\" collapse\nmechanism or only a few preferred collapse mechanisms (out of the Ns(Ns+1)2 possible mechanisms) in\neither principal direction of the building. If multiple preferred collapse mechanisms exist, they would be\nclustered together with significant story-overlap amongst them.\nThe simulations of the four models under idealized ground motion waveforms where collapse occurs do\nnot show the formation of a single (unique) collapse mechanism. However, in each model only one to five\nv collapse mechanisms occur out of a possible 153 mechanisms in each principal direction of the building.\nFurthermore, if two or more preferred mechanisms do exist, they have significant story-overlap, typically\nseparated by just one story. For example, the strongly preferred collapse mechanisms in the existing building\nmodel (perfect connections) under X direction excitation occur between floors 3 and 9, and floors 4 and 9,\nwhile the weakly preferred mechanisms occur between floors 3 and 8, and floors 4 and 8 (four preferred\nmechanisms out of 153 possible mechanisms, all clustered together within a narrow story zone; two of these\nmechanisms are in fact a subset of the other two mechanisms).\nThe characteristic and/or preferred collapse mechanisms can be identified by applying the Principle\nof Virtual Work to all possible quasi-shear bands in a building. Based on plastic analysis principles, the\nband that is destabilized by the smallest acceleration of the over-riding block of stories is the characteristic\ncollapse mechanism. If one or more bands exist that have destabilizing accelerations close to that of the\ncharacteristic collapse band, say within 5%, then these bands may evolve into collapse mechanisms as well.\nThis method identifies all the preferred collapse mechanisms in all four building models satisfactorily.\nOne application of the structural response database built for the sensitivity study is the rapid estimation\nof structural response immediately following an earthquake if the ground motion records become available.\nThe best fit of the idealized wave-trains in the database to the ground motion record can be determined using\nthe least absolute deviation method. The corresponding key structural response metrics can be extracted\nfrom the database using a simple table look-up approach. Such a method, when applied to a suite of nearsource\nrecords, predicts peak transient IDR remarkably well. Gaussian mean estimation error on the peak\ntransient IDR is 0.0006, with a standard deviation of 0.0069. A minor modification to this approach is\nneeded when applying it to multi-cycle far-field records. This modified approach is used to estimate the\npeak transient IDR response of the buildings under synthetic waveforms from a large hypothetical San\nAndreas fault earthquake. The Gaussian mean error for this estimation is 0.0011, with a standard deviation\nof 0.0209, slightly worse than for the near-source records, nevertheless within one \"performance level\"\n- good enough for emergency response decision-making. The same approach can be used for ball-park\nestimation of structural response under any given earthquake record, in lieu of comprehensive nonlinear\nanalysis.", "date": "2011-04-18", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2011-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2011-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "mfcollapse_rep.pdf", "url": "https://authors.library.caltech.edu/records/8spmb-x5x69/files/mfcollapse_rep.pdf" }, "pub_year": "2011", "author_list": "Krishnan, Swaminathan and Muto, Matthew" }, { "id": "https://authors.library.caltech.edu/records/rt8zd-92j05", "eprint_id": 26569, "eprint_status": "archive", "datestamp": "2023-08-19 04:44:17", "lastmod": "2024-01-13 05:32:05", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" } ] }, "title": "Case study of the collapse of a water tank", "ispublished": "unpub", "full_text_status": "public", "abstract": "A 48.76m high water tank with the supporting steel lattice comprising 5 segments with uniform member configuration is conceived. Its collapse behavior is investigated through a suite of ground motion analyses. First, the tank is analyzed under 13 three-component ground motion records from the Chi-Chi and Hokkaido earthquakes. It is shown that the tank always collapses in the same manner as a result of overturning due to P-Delta instability resulting from column and brace buckling at the base. This is the consequence of the uniform member sizing in each of the five segments of the supporting lattice. Incremental dynamic\nanalyses are performed using the Takatori near-source record from the 1995 Kobe earthquake. It is shown\nthat the structure collapses at a ground motion scaling factor of 0.32. The FRAME3D model of the tank\nreveals severe buckling in the bottom mega-columns on the west face of the tower, followed almost instantaneously\nby compression brace buckling on the north and south faces, when the structure is hit by the Takatori near-source pulse, resulting a tilt in the structure. Subsequent shaking induces P-Delta instability resulting in complete collapse of the tank. To aid in the evaluation of the collapse-prediction capability of competing methodologies, detailed results (time-history plots as well as ordinates of crests and troughs in these histories) are provided for the analysis at 0.32 scaling.", "date": "2010-12-14", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2010-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2010-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2010_01_Krishnan.pdf", "url": "https://authors.library.caltech.edu/records/rt8zd-92j05/files/EERL_2010_01_Krishnan.pdf" }, "pub_year": "2010", "author_list": "Krishnan, Swaminathan" }, { "id": "https://authors.library.caltech.edu/records/3gvm3-7w866", "eprint_id": 26567, "eprint_status": "archive", "datestamp": "2023-08-20 01:39:12", "lastmod": "2024-01-13 05:32:01", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" } ] }, "title": "FRAME3D V2.0 - A Program for the Three-Dimensional\n Nonlinear Time-History Analysis of\n Steel Structures: User Guide", "ispublished": "unpub", "full_text_status": "public", "abstract": "This is Version 2.0 of the user guide and should be used along with Version 2.0 of the program. Updates\ninclude: 1. Realistic PMM interaction surfaces for plastic hinge elements (output file PMM). 2. 5-Segment\nmodified elastofiber element for brace and slender column modeling. 3. Eigen value problem solver using\nsubspace iteration (output files MODES and EIGEN). 4. Output the sum of forces of groups of elements\n(output file ELMGRPRES). Additional input is required as a result of these additions to the program. However,\nthe example input files shown in chapter 6 correspond to the input format from Version 1.0 and do not\nreflect the changes in the input file from Version 1.0 to Version 2.0.\nUpdates in Version 1.1 include: 1. Output files FRAC, FRACSUM, and FRACTOT, summarizing the\nfractures in the elastofiber beam elements; 2. Output file RUP listing the fibers that have ruptured during\nthe course of the analysis; 3. Output file FAIL listing the elastofiber elements that have a complete segment\nfailure; 4. Output files FEMA356 and PERF summarizing the performance of the beams, columns, and\npanel zones, relative to the Federal Emergency Management Agency document FEMA356 (FEMA 2000)\nacceptance criteria; 5. Output files XDRFT, YDRFT, AVGPKDRFT, and PKDRFT listing the average and\npeak interstory drifts in the building. Additional input is required for this output processing. In addition,\nsome typographical errors in the version 1.0 of the user guide were also corrected, the most notable of these\nbeing sections 4.1.8 and 4.1.9 dealing with elastofiber element fiber fracture.\nFRAME3D is a program for the three-dimensional nonlinear analysis of steel buildings. It aims to\novercome the computational challenges posed by full 3D analysis of steel buildings subject to earthquake\nground motion through efficient finite elements that are designed to capture the essence of material behavior\nand geometry evolution. The element library consists of a plastic hinge beam element, an elastofiber beam\nelement, a 5-segment modified elastofiber element, a panel zone element, a 4-noded diaphragm element to\nmodel floor slabs, and an elastic translational/rotational spring element to model foundations and compliant\nsupports. The program utilizes a Newton-Raphson iteration strategy applied to an implicit Newmark timeintegration\nscheme to solve the nonlinear equations of motion at each time-step. Geometric nonlinearity and\nshear deformation are included in the formulation. This document serves as a User Guide to the program.\nAll the input and output variables encountered by the user are described here along with brief descriptions of\nthe various types of elements. In addition, 2 examples illustrating the capabilities and usage of the program\nare presented. Finally a glossary of all the variables is alphabetically listed at the end of the document.", "date": "2009-05-04", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2009-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2009-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2009-04.pdf", "url": "https://authors.library.caltech.edu/records/3gvm3-7w866/files/EERL2009-04.pdf" }, "pub_year": "2009", "author_list": "Krishnan, Swaminathan" }, { "id": "https://authors.library.caltech.edu/records/4yssk-sd448", "eprint_id": 26568, "eprint_status": "archive", "datestamp": "2023-08-20 01:39:31", "lastmod": "2024-01-13 05:32:03", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" } ] }, "title": "On the Modeling of Elastic and Inelastic, Critical- and Post-Buckling Behavior of Slender Columns and Bracing Members", "ispublished": "unpub", "full_text_status": "public", "abstract": "Analyzing tall braced frame buildings with thousands of degrees of freedom in three dimensions subject to\nstrong earthquake ground motion requires an efficient brace element that can capture the overall features of\nits elastic and inelastic response under axial cyclic loading without unduly heavy discretization. This report\ndetails the theory of a modified elastofiber (MEF) element developed to model braces and buckling-sensitive\nslender columns in such structures. The MEF element consists of three fiber segments, two at the member\nends and one at mid-span, with two elastic segments sandwiched in between. The segments are demarcated\nby two exterior nodes and four interior nodes. The fiber segments are divided into 20 fibers in the crosssection\nthat run the length of the segment. The fibers exhibit nonlinear axial stress-strain behavior akin to\nthat observed in a standard tension test in the laboratory, with a linear elastic portion, a yield plateau, and a\nstrain hardening portion consisting of a segment of an ellipse. All the control points on the stress-strain law\nare user-defined. The elastic buckling of a member is tracked by updating both exterior and interior nodal\ncoordinates at each iteration of a time step, and checking force equilibrium in the updated configuration.\nInelastic post-buckling response is captured by fiber yielding in the nonlinear segments. A user-defined\nprobability distribution for the fracture strain of a fiber in a nonlinear segment enables the modeling of\npremature fracture, observed routinely in cyclic tests of braces. If the probabilistically determined fracture\nstrain of a fiber exceeds the rupture strain, then the fiber will rupture rather than fracturing. While a fractured\nfiber can take compression, it is assumed that a ruptured fiber cannot. Handling geometric and material nonlinearity\nin such a manner allows the accurate simulation of member-end yielding, mid-span elastic buckling\nand inelastic post-buckling behavior, with fracture or rupture of fibers leading to complete severing of the\nbrace. The element is integrated into the nonlinear analysis framework for the 3-D analysis of steel buildings,\nFRAME3D. A series of simple example problems with analytical solutions, in conjunction with data\nfrom a variety of cyclic load tests, is used to calibrate and validate the element. Using a fiber segment length\nof 2% of the element length ensures that the elastic critical buckling load predicted by the MEF element is\nwithin 5% of the Euler buckling load for box and I-sections with a wide range of slenderness ratios (L/r =\n40, 80, 120, 160, and 200) and support conditions (pinned-pinned, pinned-fixed, and fixed-fixed). Elastic\npost-buckling of the Koiter-Roorda L-frame (tubes and I-sections) with various member slenderness ratios\n(L/r = 40, 80, 120, 160, and 200) is simulated and shown to compare well against second-order analytical\napproximations to the solution. The inelastic behavior of struts under cyclic loading observed in the Black\net al. and the Fell et al. experiments is numerically simulated using MEF elements. Certain parameters of\nthe model (e.g., fracture strain, initial imperfection, support conditions, etc.) that are not controllable and/or\nunmeasured during the tests are tuned to realize the best possible fit between the numerical results and the\nexperimental data. A similar comparison is made between numerical results using the MEF element and the\nexperimental data by Tremblay et al. collected from cyclic testing of single-bay braced frames. Finally, a\nFRAME3D model of a full-scale 6-story braced frame structure that was pseudodynamically tested by the\nBuilding Research Institute of Japan subjected to the 1978 Miyagi-Ken-Oki earthquake record, is analyzed\niv\nand shown to closely mimic the experimentally observed behavior. To summarize, the MEF element is able\nto incorporate all the characteristic features of slender columns and braces that significantly affect their elastic\nand inelastic, critical and post-buckling behavior, and is remarkably effective in capturing the essence of\nsaid behavior, even with the vast uncertainty associated with the buckling phenomenon.\nTo aid in the evaluation of the collapse-prediction capability of competing methodologies, a benchmark\nproblem of a water-tank subjected to the Takatori near-source record from the 1995 Kobe earthquake, scaled\ndown by a factor of 0.32, is proposed. The water-tank is so configured as to have a unique collapse mechanism\n(under all forms of ground motion), of overturning due to P - instability resulting from column and\nbrace buckling at the base. A FRAME3D model of the tank reveals severe buckling in the bottom megacolumns\non the west face of the tower, followed almost instantaneously by compression brace buckling on\nthe north and south faces, when the structure is hit by the Takatori near-source pulse, resulting a tilt in the\nstructure. Subsequent shaking induces P - instability resulting in complete collapse of the tank.", "date": "2009-05-04", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2009-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2009-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2009_03_Krishnan.pdf", "url": "https://authors.library.caltech.edu/records/4yssk-sd448/files/EERL_2009_03_Krishnan.pdf" }, "pub_year": "2009", "author_list": "Krishnan, Swaminathan" }, { "id": "https://authors.library.caltech.edu/records/t7vpd-nhj08", "eprint_id": 41596, "eprint_status": "archive", "datestamp": "2023-08-20 00:44:57", "lastmod": "2024-01-13 06:04:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheung-Sai-Hung", "name": { "family": "Cheung", "given": "Sai Hung" }, "orcid": "0000-0003-2324-3884" } ] }, "title": "Stochastic Analysis, Model and Reliability Updating of Complex Systems with Applications to Structural Dynamics", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - EERL_2009_02_Cheung.pdf
", "abstract": "In many engineering applications, it is a formidable task to construct mathematical models\nthat are expected to produce accurate predictions of the behavior of a system of interest.\nDuring the construction of such predictive models, errors due to imperfect modeling and\nuncertainties due to incomplete information about the system and its environment (e.g.,\ninput or excitation) always exist and can be accounted for appropriately by using\nprobability logic. To assess the system performance subjected to dynamic excitations, a\nstochastic system analysis considering all the uncertainties involved has to be performed. In\nengineering, evaluating the robust failure probability (or its complement, robust reliability)\nof the system is a very important part of such stochastic system analysis. The word 'robust'\nis used because all uncertainties, including those due to modeling of the system, are taken\ninto account during the system analysis, while the word 'failure' is used to refer to\nunacceptable behavior or unsatisfactory performance of the system output(s). Whenever\npossible, the system (or subsystem) output (or maybe input as well) should be measured to\nupdate models for the system so that a more robust evaluation of the system performance\ncan be obtained. In this thesis, the focus is on stochastic system analysis, model and\nreliability updating of complex systems, with special attention to complex dynamic systems\nwhich can have high-dimensional uncertainties, which are known to be a very challenging\nproblem. Here, full Bayesian model updating approach is adopted to provide a robust and\nrigorous framework for these applications due to its ability to characterize modeling\nuncertainties associated with the underlying system and to its exclusive foundation on the\nprobability axioms. First, model updating of a complex system which can have high-dimensional uncertainties\nwithin a stochastic system model class is considered. To solve the challenging\ncomputational problems, stochastic simulation methods, which are reliable and robust to\nproblem complexity, are proposed. The Hybrid Monte Carlo method is investigated and it\nis shown how this method can be used to solve Bayesian model updating problems of\ncomplex dynamic systems involving high-dimensional uncertainties. New formulae for\nMarkov Chain convergence assessment are derived. Advanced hybrid Markov Chain\nMonte Carlo simulation algorithms are also presented in the end.\nNext, the problem of how to select the most plausible model class from a set of competing\ncandidate model classes for the system and how to obtain robust predictions from these\nmodel classes rigorously, based on data, is considered. To tackle this problem, Bayesian\nmodel class selection and averaging may be used, which is based on the posterior\nprobability of different candidate classes for a system. However, these require calculation\nof the evidence of the model class based on the system data, which requires the\ncomputation of a multi-dimensional integral involving the product of the likelihood and\nprior defined by the model class. Methods for solving the computationally challenging\nproblem of evidence calculation are reviewed and new methods using posterior samples are\npresented.\nMultiple stochastic model classes can be created even there is only one embedded\ndeterministic model. These model classes can be viewed as a generalization of the\nstochastic models considered in Kalman filtering to include uncertainties in the parameters\ncharacterizing the stochastic models. State-of-the-art algorithms are used to solve the\nchallenging computational problems resulting from these extended model classes. Bayesian\nmodel class selection is used to evaluate the posterior probability of an extended model\nclasse and the original one to allow a data-based comparison. The problem of calculating\nrobust system reliability is also addressed. The importance and effectiveness of the\nproposed method is illustrated with examples for robust reliability updating of structural systems. Another significance of this work is to show the sensitivity of the results of\nstochastic analysis, especially the robust system reliability, to how the uncertainties are\nhandled, which is often ignored in past studies.\nA model validation problem is then considered where a series of experiments are conducted\nthat involve collecting data from successively more complex subsystems and these data are\nto be used to predict the response of a related more complex system. A novel methodology\nbased on Bayesian updating of hierarchical stochastic system model classes using such\nexperimental data is proposed for uncertainty quantification and propagation, model\nvalidation, and robust prediction of the response of the target system. Recently-developed\nstochastic simulation methods are used to solve the computational problems involved.\nFinally, a novel approach based on stochastic simulation methods is developed using\ncurrent system data, to update the robust failure probability of a dynamic system which will\nbe subjected to future uncertain dynamic excitations. Another problem of interest is to\ncalculate the robust failure probability of a dynamic system during the time when the\nsystem is subjected to dynamic excitation, based on real-time measurements of some output\nfrom the system (with or without corresponding input data) and allowing for modeling\nuncertainties; this generalizes Kalman filtering to uncertain nonlinear dynamic systems. For\nthis purpose, a novel approach is introduced based on stochastic simulation methods to\nupdate the reliability of a nonlinear dynamic system, potentially in real time if the\ncalculations can be performed fast enough.", "date": "2009-01-28", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2009-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2009-02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2009_02_Cheung.pdf", "url": "https://authors.library.caltech.edu/records/t7vpd-nhj08/files/EERL_2009_02_Cheung.pdf" }, "pub_year": "2009", "author_list": "Cheung, Sai Hung" }, { "id": "https://authors.library.caltech.edu/records/7g11e-68p11", "eprint_id": 26566, "eprint_status": "archive", "datestamp": "2023-08-19 23:59:19", "lastmod": "2024-01-13 05:31:59", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheung-Sai-Hung", "name": { "family": "Cheung", "given": "Sai Hung" }, "orcid": "0000-0003-2324-3884" }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "New Bayesian Updating Methodology for Model Validation and Robust Predictions Based on Data from Hierarchical Subsystem Tests", "ispublished": "unpub", "full_text_status": "public", "abstract": "In many engineering applications, it is a formidable task to construct a mathematical model\nthat is expected to produce accurate predictions of the behavior of a system of interest.\nDuring the construction of such predictive models, errors due to imperfect modeling and\nuncertainties due to incomplete information about the system and its input always exist and\ncan be accounted for appropriately by using probability logic. Often one has to decide\nwhich proposed candidate models are acceptable for prediction of the target system\nbehavior. In recent years, the problem of developing an effective model validation\nmethodology has attracted attention in many different fields of engineering and applied\nscience. Here, we consider the problem where a series of experiments are conducted that\ninvolve collecting data from successively more complex subsystems and these data are to\nbe used to predict the response of a related more complex system. A novel methodology\nbased on Bayesian updating of hierarchical stochastic system model classes using such\nexperimental data is proposed for uncertainty quantification and propagation, model\nvalidation, and robust prediction of the response of the target system. After each test stage,\nwe use all the available data to calculate the posterior probability of each stochastic system\nmodel along with the quality of its robust prediction. The proposed methodology is applied\nto the 2006 Sandia static-frame validation challenge problem to illustrate our approach for\nmodel validation and robust prediction of the system response. Recently-developed\nstochastic simulation methods are used to solve the computational problems involved.", "date": "2008-11-24", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2008-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2008-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2008_04_Joseph.pdf", "url": "https://authors.library.caltech.edu/records/7g11e-68p11/files/EERL_2008_04_Joseph.pdf" }, "pub_year": "2008", "author_list": "Cheung, Sai Hung and Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/tyfye-hfb79", "eprint_id": 26560, "eprint_status": "archive", "datestamp": "2023-08-19 19:41:38", "lastmod": "2024-01-13 05:31:47", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yamada-Masumi", "name": { "family": "Yamada", "given": "Masumi" } } ] }, "title": "Early Warning for Earthquakes with Large Rupture Dimension", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2007\n\nSubmitted - EERL2007-03.pdf
", "abstract": "Earthquake early warning systems have become popular these days, and many seismologists and engineers are making research efforts for their practical application. The existing earthquake early warning systems provide estimates of the location and size of earthquakes, and then ground motions at a site are estimated as a function of the epicentral distance and site soil properties. However, for large earthquakes, the energy is radiated from a large area surrounding the entire fault plane, and the epicenter indicates only where rupture starts.\n\nIn this project, we focus on an earthquake early warning system considering fault finiteness. We provide a new methodology to estimate rupture geometry and slip size on a finite fault in real time for the purpose of earthquake early warning.\n\nWe propose a new model to simulate high-frequency motions from earthquakes with large fault dimension: the envelope of high-frequency ground motion from a large earthquake can be expressed as a root-mean-squared combination of envelope functions from smaller earthquakes. We parameterize the fault geometry with an epicenter, a fault strike, and two along-strike rupture lengths, and find these parameters by minimizing the residual sum of squares of errors between ground motion models and observed ground motion envelopes.\n\nTo provide the information on the spatial extent of rupture geometry, we present a methodology to estimate a fault dimension of an earthquake in real time by classifying seismic records into near-source or far-source records. We analyze peak ground motions and use Bayesian model class selection to find a function that best classifies near-source and far-source records based on these parameters.\nThis discriminant function is useful to estimate the fault rupture dimension in real time, especially for large earthquakes.\n\nIn order to characterize slip on the fault in real time, we construct an analytical function to estimate slip on the fault from near-source ground displacement observations. In real-time analysis, we back project the recorded displacement data onto the fault line to estimate the size of the slip on the fault. The simulation results show that the slip size estimation predicts the observed GPS static displacement on the fault quite well. This current slip size on the fault is used for a probabilistic prediction of additional rupture length in the near future. We characterize the distribution of additional rupture length conditioned on the current slip on the fault for the ongoing rupture from the simulation with a 1-D slip model. The probability density of additional rupture length can be approximated by a lognormal distribution conditioned on the current slip size.", "date": "2008-05-28", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2007-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2007-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2007-03.pdf", "url": "https://authors.library.caltech.edu/records/tyfye-hfb79/files/EERL2007-03.pdf" }, "pub_year": "2008", "author_list": "Yamada, Masumi" }, { "id": "https://authors.library.caltech.edu/records/b9z5x-tsz56", "eprint_id": 26565, "eprint_status": "archive", "datestamp": "2023-08-19 22:33:49", "lastmod": "2024-01-13 05:31:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Olsen-Anna-H", "name": { "family": "Olsen", "given": "Anna" } } ] }, "title": "Steel Moment-Resisting Frame Responses in Simulated Strong Ground Motions: or How I Learned to Stop Worrying and Love the Big One", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2008", "abstract": "This thesis studies the response of steel moment-resisting frame buildings in simulated\nstrong ground motions. I collect 37 simulations of crustal earthquakes in California.\nThese ground motions are applied to nonlinear finite element models of four types\nof steel moment frame buildings: six- or twenty-stories with either a stiffer, higherstrength\ndesign or a more flexible, lower-strength design. I also consider the presence\nof fracture-prone welds in each design. Since these buildings experience large deformations\nin strong ground motions, the building states considered in this thesis are\ncollapse, total structural loss (must be demolished), and if repairable, the peak interstory\ndrift. This thesis maps these building responses on the simulation domains\nwhich cover many sites in the San Francisco and Los Angeles regions. The building\nresponses can also be understood as functions of ground motion intensity measures,\nsuch as pseudo-spectral acceleration (PSA), peak ground displacement (PGD), and\npeak ground velocity (PGV). This thesis develops building response prediction equations\nto describe probabilistically the state of a steel moment frame given a ground\nmotion. The presence of fracture-prone welds increases the probability of collapse by\na factor of 2-8. The probability of collapse of the more flexible design is 1-4 times\nthat of the stiffer design. The six-story buildings are slightly less likely to collapse\nthan the twenty-story buildings assuming sound welds, but the twenty-story buildings\nare 2-4 times more likely to collapse than the six-story buildings if both have fractureprone\nwelds. A vector intensity measure of PGD and PGV predicts collapse better\nthan PSA. Models based on the vector of PGD and PGV predict total structural\nloss equally well as models using PSA. PSA alone best predicts the peak inter-story\ndrift, assuming that the building is repairable. As \"rules of thumb,\" the twenty-story\nvi\nsteel moment frames with sound welds collapse in ground motions with long-period\nPGD greater than 1 m and long-period PGV greater than 2 m/s, and they are a total\nstructural loss for long-period PGD greater than 0.6 m and long-period PGV greater\nthan 1 m/s.", "date": "2008-05-28", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2008-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2008-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2008-02.pdf", "url": "https://authors.library.caltech.edu/records/b9z5x-tsz56/files/EERL2008-02.pdf" }, "pub_year": "2008", "author_list": "Olsen, Anna" }, { "id": "https://authors.library.caltech.edu/records/f3y63-42a48", "eprint_id": 26382, "eprint_status": "archive", "datestamp": "2023-08-19 19:50:15", "lastmod": "2024-01-13 05:30:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dowling-M-J", "name": { "family": "Dowling", "given": "Michael J." } } ] }, "title": "Nonlinear seismic analysis of arch dams", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1988: PB-89-194443\n\nAccepted Version - 8703.pdf
", "abstract": "A nonlinear finite element procedure for arch dams is described in which the gradual opening and closing of vertical contraction joints and predetermined horizontal cracking planes are considered. A special joint element approximately represents the deformations due to plane sections not remaining plane at each open joint and allows a single shell element discretization in the thickness direction to be used for the dam. Compressive and sliding nonlinearities are not included. Finite element treatments are also used for the water, assumed incompressible, and for the foundation rock, assumed massless, with all degrees of freedom (dof) off the dam condensed out. For efficiency in the computations, the condensed water and foundation matrices are localized in a way which maintains good accuracy. The response of Pacoima Dam to the 1971 San Fernando ground motion recorded on a ridge over one abutment and scaled by two-thirds is computed first for water at the intermediate level that existed during the 1971 earthquake and then for full reservoir. In the first analysis, the dam exhibits pronounced opening and separation of the contraction joints, allowing violation of the no-slip assumption. The presence of a full reservoir greatly increases the dam response, enough to bring some of the assumptions of the analysis into question. Reducing the ground motion scale to 0.44 with full reservoir drops the response back to a reasonable level, but the contraction joint separations remain.", "date": "2008-02-20", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1988.EERL-87-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1988.EERL-87-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8703.pdf", "url": "https://authors.library.caltech.edu/records/f3y63-42a48/files/8703.pdf" }, "pub_year": "2008", "author_list": "Dowling, Michael J." }, { "id": "https://authors.library.caltech.edu/records/937sw-2sf82", "eprint_id": 26434, "eprint_status": "archive", "datestamp": "2023-08-19 20:45:21", "lastmod": "2024-01-13 05:31:15", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Levine-Marie-Bernard P", "name": { "family": "Levine", "given": "Marie-Bernard P." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } }, { "id": "Relles-R", "name": { "family": "Relles", "given": "Raul" } } ] }, "title": "Accelerograms recorded at Caltech during the Whittier Narrows earthquakes of October 1 and 4, 1987 : a preliminary report", "ispublished": "unpub", "full_text_status": "public", "note": "PB-91-170100\n\nAccepted Version - 8801.pdf
", "abstract": "Accelerogram records were recovered from 12 stations of the California Institute of Technology strong-motion array following the Whittier Narrows earthquake of October 1, 1987 and its major aftershock on October 4, 1987. This report presents the unprocessed accelerograms as well as the seismological characteristics of these two events. The locations of the Caltech strong-motion stations are described in detail, and some preliminary results are deduced from the accelerograms. The damage produced in the Los Angeles area is also briefly described.", "date": "2008-02-19", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1988.EERL-88-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1988.EERL-88-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8801.pdf", "url": "https://authors.library.caltech.edu/records/937sw-2sf82/files/8801.pdf" }, "pub_year": "2008", "author_list": "Levine, Marie-Bernard P.; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/0tkwf-dq711", "eprint_id": 26542, "eprint_status": "archive", "datestamp": "2023-08-19 12:55:09", "lastmod": "2023-10-24 16:23:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bradford-S-C", "name": { "family": "Bradford", "given": "Samuel Case" } }, { "id": "Clinton-J-F", "name": { "family": "Clinton", "given": "John F." }, "orcid": "0000-0001-8626-2703" }, { "id": "Favela-J", "name": { "family": "Favela", "given": "J." } }, { "id": "Heaton-T-H", "name": { "family": "Heaton", "given": "T. H." }, "orcid": "0000-0003-3363-2197" } ] }, "title": "Results of Millikan Library Forced Vibration Testing", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - EERL_2004_03.pdf
", "abstract": "This report documents an investigation into the dynamic properties of Millikan Library under forced excitation. On July 10, 2002, we performed frequency sweeps from 1 Hz to 9.7 Hz in both the East-West (E-W) and North-South (N-S) directions using a roof level vibration generator. Natural frequencies were identified at 1.14 Hz (E-W fundamental mode), 1.67 Hz (N-S fundamental mode), 2.38 Hz (Torsional fundamental mode), 4.93 Hz (1st E-Wovertone), 6.57 Hz (1st Torsional overtone), 7.22 Hz (1st N-S overtone), and at 7.83 Hz (2nd E-Wovertone). The damping was estimated at 2.28% for the fundamental E-W mode and 2.39% for the N-S fundamental mode. On August 28, 2002, a modal analysis of each natural frequency was performed using the dense instrumentation network located in the building. For both the E-W and N-S fundamental modes, we observe a nearly linear increase in displacement with height, except at the ground floor which appears to act as a hinge. We observed little basement movement for the E-W mode, while in the N-S mode 30% of the roof displacement was due to basement rocking and translation. Both the E-W and N-S fundamental modes are best modeled by the first mode of a theoretical bending beam. The higher modes are more complex and not well represented by a simple structural system.", "date": "2008-02-19", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2004-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "EERL_2004_03.pdf", "url": "https://authors.library.caltech.edu/records/0tkwf-dq711/files/EERL_2004_03.pdf" }, "pub_year": "2008", "author_list": "Bradford, Samuel Case; Clinton, John F.; et el." }, { "id": "https://authors.library.caltech.edu/records/xzcac-s8013", "eprint_id": 26421, "eprint_status": "archive", "datestamp": "2023-08-19 07:23:18", "lastmod": "2024-01-13 05:31:06", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } }, { "id": "Matthiesen-R-B", "name": { "family": "Matthiesen", "given": "R. B." } }, { "id": "Hoerner-John-Brent", "name": { "family": "Hoerner", "given": "John Brent" } } ] }, "title": "Forced vibration of a 22-story steel frame building", "ispublished": "unpub", "full_text_status": "public", "note": "PB 205 161\n\nAccepted Version - 7101.pdf
", "abstract": "The 22-story steel frame structure that houses the offices of the San Diego Gas and Electric Company is a well-knovrn feature of the skyline of San Diego and is a good example of modern, high-rise office construction. Designed by the architectural firm of R. G. Wheeler and Associates, with structural design by Ferver, Dorland and Associates, the building was completed in April 1968. The building, shown in Figure 1, is owned and occupied solely by the San Diego Gas and Electric Company.\n\nBecause this building typifies many buildings in the major cities of the seismic west coast, and because a multistory office building may hold a thousand people or more during business hours, it is important that the dynamic properties of structures such as this be measured. Experimentally determined dynamic properties are required both to improve the techniques by which such properties are calculated for purposes of design, and to permit interpretation of the measured response of the building in the event of a strong earthquake. As information on the dynamic properties of tall buildings and their earthquake response accumulates, it should be possible to develop better procedures for determining the appropriate levels of earthquake loading for design. The need for special attention to the tall buildings becomes clear when it is realized that the seismic provisions of building codes are not as applicable to the newer tall buildings as they are to older types of construction.\n\nIn the tests reported below, the San Diego Gas and Electric Company Building was excited by two eccentric-mass vibration generators located on the 20th (equipment) floor and measurements of the structural response were made throughout the building from the roof to the second basement. From these measurements, which are more extensive than in previous tests of this type, it has been possible to determine frequencies, mode shapes and damping values for the first 18 modes of the structure; six each in N-S translation, E-W translation and in torsion. In another portion of the testing program the dynamic properties of the building also were determined by analysis of the measured response of the building to ambient vibration (Trifunac, 1970a). The results of these two experiments and the analytical determination of the building properties (Gobler, 1969) complete the research efforts devoted to the structure.\n\nThe experimental program was a cooperative effort between the research groups in earthquake engineering at the California. Institute of Technology and the University of California at Los Angeles. The testing, conducted on weekends to minimize disturbance to the occupants, extended over a period of approximately two months and required a crew varying between four and eight.", "date": "2008-02-19", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7101.pdf", "url": "https://authors.library.caltech.edu/records/xzcac-s8013/files/7101.pdf" }, "pub_year": "2008", "author_list": "Jennings, Paul C.; Matthiesen, R. B.; et el." }, { "id": "https://authors.library.caltech.edu/records/j1xt3-35x87", "eprint_id": 26564, "eprint_status": "archive", "datestamp": "2023-08-19 22:00:25", "lastmod": "2024-01-13 05:31:55", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wolf-Julie-Anne", "name": { "family": "Wolf", "given": "Julie Anne" } } ] }, "title": "A Plasticity Model to Predict the Effects of Confinement on Concrete", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2008", "abstract": "A plasticity model to predict the behavior of confined concrete is developed. The\nmodel is designed to implicitly account for the increase in strength and ductility due\nto confining a concrete member. The concrete model is implemented into a finite\nelement (FE) model. By implicitly including the change in the strength and ductility\nin the material model, the confining material can be explicitly included in the FE\nmodel. Any confining material can be considered, and the effects on the concrete of\nfailure in the confinement material can be modeled. Test data from a wide variety of\ndifferent concretes utilizing different confinement methods are used to estimate the\nmodel parameters. This allows the FE model to capture the generalized behavior\nof concrete under multiaxial loading. The FE model is used to predict the results\nof tests on reinforced concrete members confined by steel hoops and fiber reinforced\npolymer (FRP) jackets. Loading includes pure axial load and axial load-moment\ncombinations. Variability in the test data makes the model predictions difficult to\ncompare but, overall, the FE model is able to capture the effects of confinement on\nconcrete. Finally, the FE model is used to compare the performance of steel hoop to\nFRP confined sections, and of square to circular cross sections. As expected, circular\nsections are better able to engage the confining material, leading to higher strengths.\nHowever, higher strains are seen in the confining material for the circular sections.\nThis leads to failure at lower axial strain levels in the case of the FRP confined\nsections. Significant differences are seen in the behavior of FRP confined members\nand steel hoop confined members. Failure in the FRP members is always determined\nby rupture in the composite jacket. As a result, the FRP members continue to take\nload up to failure. In contrast, the steel hoop confined sections exhibit extensive strain\nvi\nsoftening before failure. This comparison illustrates the usefulness of the concrete\nmodel as a tool for designers. Overall, the concrete model provides a flexible and\npowerful method to predict the performance of confined concrete.", "date": "2008-01-09", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2008-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2008-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2008-01.pdf", "url": "https://authors.library.caltech.edu/records/j1xt3-35x87/files/EERL2008-01.pdf" }, "pub_year": "2008", "author_list": "Wolf, Julie Anne" }, { "id": "https://authors.library.caltech.edu/records/bpa9q-wve13", "eprint_id": 26561, "eprint_status": "archive", "datestamp": "2023-08-19 21:00:03", "lastmod": "2024-01-13 05:31:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taflanidis-Alexandros-Angelos", "name": { "family": "Taflanidis", "given": "Alexandros" }, "orcid": "0000-0002-9784-7480" } ] }, "title": "Stochastic System Design and Applications to Stochastically Robust Structural Control", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2008", "abstract": "The knowledge about a planned system in engineering design applications is never\ncomplete. Often, a probabilistic quantification of the uncertainty arising from this missing\ninformation is warranted in order to efficiently incorporate our partial knowledge about the\nsystem and its environment into their respective models. In this framework, the design\nobjective is typically related to the expected value of a system performance measure, such\nas reliability or expected life-cycle cost. This system design process is called stochastic\nsystem design and the associated design optimization problem stochastic optimization. In\nthis thesis general stochastic system design problems are discussed. Application of this\ndesign approach to the specific field of structural control is considered for developing a\nrobust-to-uncertainties nonlinear controller synthesis methodology.\nInitially problems that involve relatively simple models are discussed. Analytical\napproximations, motivated by the simplicity of the models adopted, are discussed for\nevaluating the system performance and efficiently performing the stochastic optimization.\nSpecial focus is given in this setting on the design of control laws for linear structural\nsystems with probabilistic model uncertainty, under stationary stochastic excitation. The\nanalysis then shifts to complex systems, involving nonlinear models with high-dimensional\nuncertainties. To address this complexity in the model description stochastic simulation is\nsuggested for evaluating the performance objectives. This simulation-based approach\naddresses adequately all important characteristics of the system but makes the associated\ndesign optimization challenging. A novel algorithm, called Stochastic Subset Optimization\n(SSO), is developed for efficiently exploring the sensitivity of the objective function to the\ndesign variables and iteratively identifying a subset of the original design space that has\nv i\nhigh plausibility of containing the optimal design variables. An efficient two-stage\nframework for the stochastic optimization is then discussed combining SSO with some\nother stochastic search algorithm. Topics related to the combination of the two different\nstages for overall enhanced efficiency of the optimization process are discussed.\nApplications to general structural design problems as well as structural control problems\nare finally considered. The design objectives in these problems are the reliability of the\nsystem and the life-cycle cost. For the latter case, instead of approximating the damages\nfrom future earthquakes in terms of the reliability of the structure, as typically performed in\npast research efforts, an accurate methodology is presented for estimating this cost; this\nmethodology uses the nonlinear response of the structure under a given excitation to\nestimate the damages in a detailed, component level.", "date": "2007-09-24", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2007-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2007-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2007-05.pdf", "url": "https://authors.library.caltech.edu/records/bpa9q-wve13/files/EERL2007-05.pdf" }, "pub_year": "2007", "author_list": "Taflanidis, Alexandros" }, { "id": "https://authors.library.caltech.edu/records/nr6rs-94825", "eprint_id": 26563, "eprint_status": "archive", "datestamp": "2023-08-19 20:58:40", "lastmod": "2024-01-13 05:31:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oh-Chang-Kook", "name": { "family": "Oh", "given": "Chang Kook" } } ] }, "title": "Bayesian Learning for Earthquake Engineering Applications and Structural Health Monitoring", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2007", "abstract": "Parallel to significant advances in sensor hardware, there have been recent developments\nof sophisticated methods for quantitative assessment of measured data that\nexplicitly deal with all of the involved uncertainties, including inevitable measurement\nerrors. The existence of these uncertainties often causes numerical instabilities\nin inverse problems that make them ill-conditioned.\nThe Bayesian methodology is known to provide an efficient way to alleviate this illconditioning\nby incorporating the prior term for regularization of the inverse problem,\nand to provide probabilistic results which are meaningful for decision making.\nIn this work, the Bayesian methodology is applied to inverse problems in earthquake\nengineering and especially to structural health monitoring. The proposed\nmethodology of Bayesian learning using automatic relevance determination (ARD)\nprior, including its kernel version called the Relevance Vector Machine, is presented\nand applied to earthquake early warning, earthquake ground motion attenuation estimation,\nand structural health monitoring, using either a Bayesian classification or\nregression approach.\nThe classification and regression are both performed in three phases: (1) Phase\nI (feature extraction phase): Determine which features from the data to use in a\ntraining dataset; (2) Phase II (training phase): Identify the unknown parameters\ndefining a model by using a training dataset; and (3) Phase III (prediction phase):\nPredict the results based on the features from new data.\nThis work focuses on the advantages of making probabilistic predictions obtained\nby Bayesian methods to deal with all uncertainties and the good characteristics of\nthe proposed method in terms of computationally efficient training, and, especially,\nvi\nprediction that make it suitable for real-time operation. It is shown that sparseness\n(using only smaller number of basis function terms) is produced in the regression\nequations and classification separating boundary by using the ARD prior along with\nBayesian model class selection to select the most probable (plausible) model class\nbased on the data. This model class selection procedure automatically produces\noptimal regularization of the problem at hand, making it well-conditioned.\nSeveral applications of the proposed Bayesian learning methodology are presented.\nFirst, automatic near-source and far-source classification of incoming ground motion\nsignals is treated and the Bayesian learning method is used to determine which ground\nmotion features are optimal for this classification. Second, a probabilistic earthquake\nattenuation model for peak ground acceleration is identified using selected optimal\nfeatures, especially taking a non-linearly involved parameter into consideration. It is\nshown that the Bayesian learning method can be utilized to estimate not only linear\ncoefficients but also a non-linearly involved parameter to provide an estimate for\nan unknown parameter in the kernel basis functions for Relevance Vector Machine.\nThird, the proposed method is extended to a general case of regression problems\nwith vector outputs and applied to structural health monitoring applications. It\nis concluded that the proposed vector output RVM shows promise for estimating\ndamage locations and their severities from change of modal properties such as natural\nfrequencies and mode shapes.", "date": "2007-09-17", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2007-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2007-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2007-04.pdf", "url": "https://authors.library.caltech.edu/records/nr6rs-94825/files/EERL2007-04.pdf" }, "pub_year": "2007", "author_list": "Oh, Chang Kook" }, { "id": "https://authors.library.caltech.edu/records/7ggmt-83n81", "eprint_id": 26559, "eprint_status": "archive", "datestamp": "2023-08-19 20:13:15", "lastmod": "2024-01-13 05:31:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Muto-Matthew-M", "name": { "family": "Muto", "given": "Matthew M." } } ] }, "title": "Application of Stochastic Simulation Methods to System Identification", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2007", "abstract": "Reliable predictive models for the response of structures are a necessity for many\nbranches of earthquake engineering, such as design, structural control, and structural\nhealth monitoring. However, the process of choosing an appropriate class of models\nto describe a system, known as model-class selection, and identifying the specific\npredictive model based on available data, known as system identification, is difficult.\nVariability in material properties, complex constitutive behavior, uncertainty in the\nexcitations caused by earthquakes, and limited constraining information (relatively\nfew channels of data, compared to the number of parameters needed for a useful\npredictive model) make system identification an ill-conditioned problem. In addition,\nmodel-class selection is not trivial, as it involves balancing predictive power with\nsimplicity.\nThese problems of system identification and model-class selection may be addressed\nusing a Bayesian probabilistic framework that provides a rational, transparent\nmethod for combining prior knowledge of a system with measured data and for\nchoosing between competing model classes. The probabilistic framework also allows\nfor explicit quantification of the uncertainties associated with modeling a system.\nThe essential idea is to use probability logic and Bayes' Theorem to give a measure\nof plausibility for a model or class of models that is updated with available data.\nSimilar approaches have been used in the field of system identification, but many\ncurrently used methods for Bayesian updating focus on the model defined by the set\nof most plausible parameter values. The challenge for these approaches (referred to as\nasymptotic-approximation-based methods) is when one must deal with ill-conditioned\nproblems, where there may be many models with high plausibility, rather than a single\nv\ndominant model. It is demonstrated here that ill-conditioned problems in system\nidentification and model-class selection can be effectively addressed using stochastic\nsimulation methods.\nThis work focuses on the application of stochastic simulation to updating and\ncomparing model classes in problems of: (1) development of empirical ground motion\nattenuation relations, (2) structural model updating using incomplete modal data\nfor the purposes of structural health monitoring, and (3) identification of hysteretic\nstructural models, including degrading models, from seismic structural response.\nThe results for system identification and model-class selection in this work fall into\nthree categories. First, in cases where the existing asymptotic approximation-based\nmethods are appropriate (i.e., well-conditioned problems with one highest-plausibility\nmodel), the results obtained using stochastic simulation show good agreement with\nresults from asymptotic-approximation-based methods. Second, for cases involving\nill-conditioned problems based on simulated data, stochastic simulation methods are\nsuccessfully applied to obtain results in a situation where the use of asymptotics is\nnot feasible (specfically, the identification of hysteretic models). Third, preliminary\nstudies using stochastic simulation to identify a deteriorating hysteretic model with\nrelatively sparse real data from a structure damaged in the 1994 Northridge earthquake\nshow that the high-plausibility models demonstrate behavior consistent with\nthe observed damage, indicating that there is promise in applying these methods to\nill-conditioned problems in the real world.", "date": "2007-05-21", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2007-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2007-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2007-02.pdf", "url": "https://authors.library.caltech.edu/records/7ggmt-83n81/files/EERL2007-02.pdf" }, "pub_year": "2007", "author_list": "Muto, Matthew M." }, { "id": "https://authors.library.caltech.edu/records/x03c4-78n78", "eprint_id": 26562, "eprint_status": "archive", "datestamp": "2023-08-19 19:30:37", "lastmod": "2024-01-13 05:31:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mitrani-Reiser-Judith", "name": { "family": "Mitrani-Reiser", "given": "Judith" } } ] }, "title": "An Ounce of Prevention: Probabilistic Loss Estimation for Performance-Based Earthquake Engineering", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2007", "abstract": "Performance-based earthquake engineering (PBEE) is a methodology that incorporates\ndesired performance levels into the design process. Performance in PBEE can be expressed\nin economic terms, or as elapsed downtime, or in terms of life and building safety\nobjectives. These performance objectives are relevant to various types of stakeholders.\nThey should be addressed in building loss estimation procedures because after an\nearthquake, the repair cost will not be the only \"loss\" suffered by building stakeholders. In\na sizeable earthquake, there will likely also be some losses due to business interruption\nduring the repair effort, building closure taken as a post-earthquake safety precaution, and\nhuman casualties caused by building failures during the seismic event.\nAn analytical approach for PBEE is developed and implemented to evaluate the\nperformance of a new reinforced-concrete moment-frame office building. The PBEE\napproach used is consistent with the Pacific Earthquake Engineering Research (PEER)\ncenter's modular framework, which is divided into four core analytical stages: hazard\nanalysis, structural analysis, damage analysis, and loss analysis. Future losses of the\nbuilding are uncertain because they depend on uncertain quantities, such as the shaking\nintensity of the earthquake, the mechanical properties of the facility, and the uncertain\ndamageability and unit repair costs of the facility. An analytical approach is developed to\npropagate these uncertainties. This work presents the mathematical foundation for the\ndamage and loss analyses, and a description of its implementation into software. The\nresults from running this software on multiple design variants of the building are presented,\nviii\nincluding seismic vulnerabilities as a function of shaking intensity and corresponding\nexpected annual losses.\nThe methodology developed and implemented in this work estimates the direct economic\nlosses due to repair costs as well as two types of indirect economic losses, those produced\nby building downtime and by human fatalities. A procedure for a virtual inspection is used\nto assess the safety of buildings, based on current damage assessment guidelines.\nAdditionally, a model is established to estimate human fatalities caused by the partial and\nglobal collapse of buildings, using probabilities of fatality based on relevant empirical data\nand the results of the virtual inspection process. A simplified methodology is presented for\nestimating building downtime after seismic events, including mobilization delays before\nconstruction begins and the elapsed time needed to repair damaged building components.\nThe losses due to downtime and human fatalities are then added to the building repair cost\nin order to estimate the total building loss, which is then used to perform a benefit-cost\nanalysis of the benchmark building. The work presented, is to our knowledge, the most\nfaithful attempt to estimate the main decision variables (termed the 3 Ds-dollars, deaths,\nand downtime), proposed by PEER and the ATC-58 Project for performance assessment of\nstructures.", "date": "2007-01-08", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL2007-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL2007-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2007-01.pdf", "url": "https://authors.library.caltech.edu/records/x03c4-78n78/files/EERL2007-01.pdf" }, "pub_year": "2007", "author_list": "Mitrani-Reiser, Judith" }, { "id": "https://authors.library.caltech.edu/records/4s9bq-ycg68", "eprint_id": 26556, "eprint_status": "archive", "datestamp": "2023-08-19 18:38:15", "lastmod": "2023-10-24 16:24:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" }, { "id": "Xu-Xin", "name": { "family": "Xu", "given": "Xin" } } ] }, "title": "Analysis of Simultaneous Operational Failure of Critical Facilities due to Earthquake, for a California Utlity", "ispublished": "unpub", "full_text_status": "public", "abstract": "This study presents an estimate of the probability that a single earthquake could cause\nsimultaneous operational failure of geographically disperse data centers operated by a\nCalifornia utility. Three facilities are considered: a grid control facility (denoted herein by\nGCF), a data processing facility (DPF), and a backup data facility (BDF) that can perform\nthe functions of either GCF or DPF, should either be rendered inoperative. This study\nestimates two probabilities: (1) that within the next 5 years a single earthquake could render\nboth the grid control and backup facilities inoperative; and (2) that within the next 5 years a\nsingle earthquake could render both the data processing and backup facilities inoperative.\nThe work was performed by researchers at the California Institute of Technology in\nPasadena, CA, in collaboration with researchers at the United States Geological Survey in\nPasadena, CA and Golden, CO. Caltech designed and directed the research, examined the\nseismic vulnerability of the three sites, and quantified the two probabilities desired. The\nUSGS performed the hazard analysis.", "date": "2006-09-22", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2006-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2006-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2006-01_-_Porter.pdf", "url": "https://authors.library.caltech.edu/records/4s9bq-ycg68/files/EERL2006-01_-_Porter.pdf" }, "pub_year": "2006", "author_list": "Porter, Keith A.; Krishnan, Swaminathan; et el." }, { "id": "https://authors.library.caltech.edu/records/n1zsj-yj341", "eprint_id": 26558, "eprint_status": "archive", "datestamp": "2023-08-19 18:18:32", "lastmod": "2023-10-24 16:24:16", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bradford-S-C", "name": { "family": "Bradford", "given": "Samuel Case" } } ] }, "title": "Time-Frequency Analysis of Systems with Changing Dynamic Properties", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2007", "abstract": "Time-frequency analysis methods transform a time series into a two-dimensional representation\nof frequency content with respect to time. The Fourier Transform identifies\nthe frequency content of a signal (as a sum of weighted sinusoidal functions) but\ndoes not give useful information regarding changes in the character of the signal, as all\ntemporal information is encoded in the phase of the transform. A time-frequency representation,\nby expressing frequency content at different sections of a record, allows\nfor analysis of evolving signals. The time-frequency transformation most commonly\nencountered in seismology and civil engineering is a windowed Fourier Transform, or\nspectrogram; by comparing the frequency content of the first portion of a record with\nthe last portion of the record, it is straightforward to identify the changes between\nthe two segments. Extending this concept to a sliding window gives the spectrogram,\nwhere the Fourier transforms of successive portions of the record are assembled into a\ntime-frequency representation of the signal. The spectrogram is subject to an inherent\nresolution limitation, in accordance with the uncertainty principle, that precludes\na perfect representation of instantaneous frequency content. The wavelet transform\nwas introduced to overcome some of the shortcomings of Fourier analysis, though\nwavelet methods are themselves unsuitable for many commonly encountered signals.\nThe Wigner-Ville Distribution, and related refinements, represent a class of advanced\ntime-frequency analysis tools that are distinguished from Fourier and wavelet\nmethods by an increase in resolution in the time-frequency plane. I introduce several\ntime-frequency representations and apply them to various synthetic signals as well as\nsignals from instrumented buildings.\nvi\nFor systems of interest to engineers, investigating the changing properties of a\nsystem is typically performed by analyzing vibration data from the system, rather\nthan direct inspection of each component. Nonlinear elastic behavior in the forcedisplacement\nrelationship can decrease the apparent natural frequencies of the system\n- these changes typically occur over fractions of a second in moderate to strong excitation\nand the system gradually recovers to pre-event levels. Structures can also suffer\npermanent damage (e.g., plastic deformation or fracture), permanently decreasing the\nobserved natural frequencies as the system loses stiffness. Advanced time-frequency\nrepresentations provide a set of exploratory tools for analyzing changing frequency\ncontent in a signal, which can then be correlated with damage patterns in a structure.\nModern building instrumentation allows for an unprecedented investigation into\nthe changing dynamic properties of structures: a framework for using time-frequency\nanalysis methods for instantaneous system identification is discussed.", "date": "2006-07-19", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2006-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2006-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2006-02.pdf", "url": "https://authors.library.caltech.edu/records/n1zsj-yj341/files/EERL2006-02.pdf" }, "pub_year": "2006", "author_list": "Bradford, Samuel Case" }, { "id": "https://authors.library.caltech.edu/records/xze43-bdq08", "eprint_id": 26553, "eprint_status": "archive", "datestamp": "2023-08-19 14:50:30", "lastmod": "2024-01-13 05:31:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cua-Georgia-B", "name": { "family": "Cua", "given": "Georgia B." } } ] }, "title": "Creating the Virtual Seismologist: developments in ground motion characterization and seismic early warning", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - 01gcua_acknow.pdf
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", "abstract": "The Virtual Seismologist method for earthquake early warning uses a Bayesian approach\nto find the most probable magnitude and location estimates given the incoming\nground motions envelopes from a rupturing earthquake. Ground motion ratios and\nground motion envelope attenuation relationships are used to estimate magnitude and\nepicentral location as early as 3 seconds after the initial P wave detection. The use\nof prior information distinguishes this method from other proposed methods for seismic\nearly warning. The state of health of the seismic network, previously observed\nseismicity, fault locations, and the Gutenberg-Richter relationship are the types of\nprior information useful in resolving trade-offs in the initial source estimates which\nare unresolved by the limited data. Short-term earthquake forecasts are ideal priors\nfor seismic early warning.\nHaving a high density of stations with real-time telemetry reduces the complexity\ninvolved in finding the most probable source estimates and communicating these\nestimates to early warning subscribers. The benefits of prior information are most\nevident for regions with low station density. Most early warning studies are focused\nexclusively on either the source estimation problem, or how subscribers use the warning\ninformation. The inclusion of prior information ultimately requires a level of\ncoordination and communication between the network broadcasting the early warning\ninformation and the subscribers that is not consistent with this divide. The need\nfor a more integrated approach to seismic early warning which considers the source\nestimation and user response as interacting and interrelated parts of a single problem\nis discussed.\nA parameterization that decomposes observed ground motion envelopes into Pwave,\nS-wave, and ambient noise envelopes is developed and applied to a large suite of\nobserved ground motion envelopes recorded within 200 km of 2 ! M ! 7.3 Southern\nCalifornia earthquakes. Separate attenuation relationships are developed to describe\nvi\nthe magnitude, distance, and site dependence of various channels of P- and S-wave\nenvelopes. The P-wave relationships allow the early warning source estimates to be\nobtained from observed P-wave amplitudes. Aside from early warning applications,\nthese envelope attenuation relationships are used to investigate the average properties\nof ground motions recorded by the Southern California Seismic Network. Stationspecific\namplification factors for 150 Southern California Seismic Network stations\nwere obtained for horizontal and vertical acceleration, velocity, and displacement\namplitudes, and are included (Excel format) as external multimedia objects.", "date": "2006-03-15", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-12", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-12", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "17gcua_appendixA.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/17gcua_appendixA.pdf" }, "related_objects": [ { "basename": "Z.a.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.a.rock.PS.stacorr.xls" }, { "basename": "Z.v.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.v.soil.PS.stacorr.xls" }, { "basename": "10gcua_chapter5.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/10gcua_chapter5.pdf" }, { "basename": "19gcua_appendixC.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/19gcua_appendixC.pdf" }, { "basename": "ENU.a.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.a.soil.PS.stacorr.xls" }, { "basename": "Z.d.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.d.soil.PS.stacorr.xls" }, { "basename": "01gcua_acknow.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/01gcua_acknow.pdf" }, { "basename": "07gcua_chapter2.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/07gcua_chapter2.pdf" }, { "basename": "11gcua_chapter6.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/11gcua_chapter6.pdf" }, { "basename": "24gcua_vita.doc", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/24gcua_vita.doc" }, { "basename": "ENU.d.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.d.soil.PS.stacorr.xls" }, { "basename": "ENU.v.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.v.rock.PS.stacorr.xls" }, { "basename": "ENU.v.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.v.soil.PS.stacorr.xls" }, { "basename": "Z.v.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.v.rock.PS.stacorr.xls" }, { "basename": "05gcua_listtabs.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/05gcua_listtabs.pdf" }, { "basename": "12gcua_chapter7.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/12gcua_chapter7.pdf" }, { "basename": "13gcua_chapter8.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/13gcua_chapter8.pdf" }, { "basename": "15gcua_chapter10.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/15gcua_chapter10.pdf" }, { "basename": "16gcua_bibl.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/16gcua_bibl.pdf" }, { "basename": "20gcua_appendixD.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/20gcua_appendixD.pdf" }, { "basename": "03gcua_toc.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/03gcua_toc.pdf" }, { "basename": "09gcua_chapter4.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/09gcua_chapter4.pdf" }, { "basename": "22gcua_appendixF.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/22gcua_appendixF.pdf" }, { "basename": "08gcua_chapter3.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/08gcua_chapter3.pdf" }, { "basename": "21gcua_appendixE.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/21gcua_appendixE.pdf" }, { "basename": "23gcua_appendixG.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/23gcua_appendixG.pdf" }, { "basename": "ENU.d.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.d.rock.PS.stacorr.xls" }, { "basename": "Z.a.soil.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.a.soil.PS.stacorr.xls" }, { "basename": "04gcua_listfigs.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/04gcua_listfigs.pdf" }, { "basename": "06gcua_chapter1.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/06gcua_chapter1.pdf" }, { "basename": "14gcua_chapter9.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/14gcua_chapter9.pdf" }, { "basename": "18gcua_appendixB.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/18gcua_appendixB.pdf" }, { "basename": "ENU.a.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/ENU.a.rock.PS.stacorr.xls" }, { "basename": "Z.d.rock.PS.stacorr.xls", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/Z.d.rock.PS.stacorr.xls" }, { "basename": "02gcua_abstract.pdf", "url": "https://authors.library.caltech.edu/records/xze43-bdq08/files/02gcua_abstract.pdf" } ], "pub_year": "2006", "author_list": "Cua, Georgia B." }, { "id": "https://authors.library.caltech.edu/records/55129-q9872", "eprint_id": 26555, "eprint_status": "archive", "datestamp": "2023-08-19 16:36:48", "lastmod": "2023-10-24 16:24:08", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Grasso-V-F", "name": { "family": "Grasso", "given": "Veronica F." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Manfredi-G", "name": { "family": "Manfredi", "given": "Gaetano" } } ] }, "title": "Seismic Early Warning Systems: Procedure for Automated Decision Making", "ispublished": "unpub", "full_text_status": "public", "abstract": "An Early Warning System potentially allows mitigation measures to be carried out from the moment in which a seismic event is detected. Examples of such measures are evacuation of buildings, shut-down of critical systems (nuclear reactors, industrial chemical processes, etc.) and stopping of high-speed trains. The type of mitigation measures that can be effectively activated depends on the amount of warning time available, but timeliness is often in conflict with the reliability of the predictions, which become more accurate as more seismic sensor data is collected. There is therefore an inevitable trade-off between the amount of warning time available and the reliability of the predictions provided by the Early Warning System. To investigate this trade-off, the consequences of the two alternatives of taking mitigation actions or not acting must be analyzed, accounting for significant uncertainty in the predictions.\nIn this report, we present a decision-making procedure based on the real-time evaluation of the consequences of taking no action and of activating mitigation measures which is based on the probabilities of false and missed alerts. The threshold at which mitigating actions should be taken is quantified based on a cost-benefit analysis. The method is applied to two recent seismic events in Southern California, an M 4.75 event in Yorba Linda and an M 6.5 event in San Simeon. Also, a feasibility assessment of any proposed regional Early Warning System is of critical importance, and it should involve an examination of whether the requirements, in terms of warning time available and the probability of making wrong decisions, are met. A useful tool in this assessment of an Early Warning System is a seismic hazard map to provide the probability of exceedance of ground shaking intensity, given a site and time interval of interest, and a corresponding map of the probability of making a wrong decision. In this report, a methodology is presented for estimating the probabilities of making wrong decisions that can be incorporated in a feasibility assessment of proposed Early Warning System.", "date": "2005-11-01", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2005-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2005-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2005-02.pdf", "url": "https://authors.library.caltech.edu/records/55129-q9872/files/EERL2005-02.pdf" }, "pub_year": "2005", "author_list": "Grasso, Veronica F.; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/4qemw-m0q51", "eprint_id": 26554, "eprint_status": "archive", "datestamp": "2023-08-19 16:07:36", "lastmod": "2024-01-13 05:31:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" }, { "id": "Ji-Chen", "name": { "family": "Ji", "given": "Chen" }, "orcid": "0000-0002-0350-5704" }, { "id": "Komatitsch-D", "name": { "family": "Komatitsch", "given": "Dimitri" } }, { "id": "Tromp-J", "name": { "family": "Tromp", "given": "Jeroen" }, "orcid": "0000-0002-2742-8299" } ] }, "title": "Performance of 18-Story Steel Momentframe Buildings during a large San Andreas Earthquake - A Southern California-Wide End-to-End Simulation", "ispublished": "unpub", "full_text_status": "public", "abstract": "The mitigation of seismic risk in urban areas in the United States and abroad is of major concern for all governments.\nUnfortunately no comprehensive studies have attempted to address this issue in a rigorous, quantitative manner. This\nstudy tackles this problem head-on for one typical class of tall buildings in southern California. The approach adopted\nhere can be used as a template to study earthquake risk in other seismically sensitive regions of the world, such as\nTaiwan, Japan, Indonesia, China, South American countries (Chile, Bolivia, etc.), and the west coast of the United\nStates (in particular, Seattle).\nIn 1857 a large earthquake of magnitude 7.9 [1] occurred on the San Andreas fault with rupture initiating at\nParkeld in Central California and propagating in a southeasterly direction over a distance of more than 360 km.\nSuch a unilateral rupture produces signicant directivity toward the San Fernando and Los Angeles basins. Indeed,\nnewspaper reports (Los Angeles Star [2, 3]) of sloshing observed in the Los Angeles river point to long-duration (1-2\nmin) and long-period (2-8 s) shaking, which could have a severe impact on present-day tall buildings, especially in\nthe mid-height range. To assess the risk posing tall steel moment-frame buildings from an 1857-like earthquake on the\nSan Andreas fault, a nite source model of the magnitude 7.9 November 3, 2002 Denali fault earthquake is mapped\non to the San Andreas fault with rupture initiating at Parkeld in Central California and propagating a distance of\nabout 290 km in a south-easterly direction. As the rupture proceeds down south from Parkeld and hits the big bend\non the San Andreas fault, it sheds off a signicant amount of energy into the San Fernando valley, generating large\namplitude ground motion there. A good portion of this energy spills over into the Los Angeles basin with many cities\nalong the coast such as Santa Monica and Seal Beach and more inland areas going east from Seal beach towards\nAnaheim experiencing long-duration shaking. In addition, the tail-end of the rupture sheds energy from SH/Love\nwaves into the Baldwin Park-La Puente region, which is bounded by a line of mountains that creates a mini-basin,\nfurther amplifying the ground motion. The peak velocity is of the order of 1 m.s in the Los Angeles basin, including\ndowntown Los Angeles, and 2 m.s in the San Fernando valley. Signicant displacements occur in the basins but not\nin the mountains. The peak displacements are in the neighborhood of 1 m in the Los Angeles basin and 2 m in the San\nFernando valley. The ground motion simulation is performed using the spectral element method based seismic wave\npropagation program, SPECFEM3D.\nTo study the effects of the ground motion simulated at 636 sites (spread across southern California, spaced at\nabout 3.5 km each way), computer models of an existing 18-story steel moment-frame building and a redesigned\nbuilding with the same conguration (redesigned to current standards using the 1997 Uniform Building Code) are\nanalyzed using the nonlinear structural analysis program, FRAME3D. For these analyses, the building Y direction is\naligned with the geographical north direction. As expected, the existing building model fares much worse than the\nredesigned building model. Fracture occurs in at least 25% of the connections in this building when located in the\nSan Fernando valley. About 10% of connections fracture in the building when located in downtown Los Angeles and\nthe mid-Wilshire district (Beverly Hills), while the numbers are about 20% when it is located in Santa Monica, west\nLos Angeles, Inglewood , Alhambra, Baldwin Park, La Puente, Downey, Norwalk, Brea, Fullerton, Anaheim and Seal\nBeach. The peak interstory drifts in the middle-third and bottom-third of the existing building are far greater than the\ntop-third pointing to damage being localized to the lower oors. The localization of damage in the lower oors rather\nthan the upper oors could potentially be worse because of the risk of more oors pancaking on top of each other if a\nsingle story gives way. Consistent with the extent of fracture observed, the peak drifts in the existing building exceed\n0.10 when located in the San Fernando valley, Baldwin Park and neighboring cities, Santa Monica, west Los Angeles\nand neighboring cities, Norwalk and neighboring cities, and Seal Beach and neighboring cities, which is well into the postulated collapse regime. When located in downtown Los Angeles and the mid-Wilshire district, the building would\nbarely satisfy the collapse prevention criteria set by FEMA [4] with peak drifts of about 0.05.\nThe performance of the newly designed 18-story steel building is signicantly better than the existing building for\nthe entire region. However, the new building still has signicant drifts indicative of serious damage when located in\nthe San Fernando valley or the Baldwin Park area. When located in coastal cities (such as Santa Monica, Seal Beach\netc.), the Wilshire-corridor (west Los Angeles, Beverly Hills, etc.), the mid-city region (Downey, Norwalk, etc.) or\nthe booming Orange County cities of Anaheim and Santa Ana, it has peak drifts of about 0.05, once again barely\nsatisfying the FEMA collapse prevention criteria [5]. In downtown Los Angeles it does not undergo much damage in\nthis scenario. Thus, even though this building has been designed according to the latest code, it suffers damage that\nwould necessitate closure for some time following the earthquake in most areas, but this should be expected since this\nis a large earthquake and building codes are written to limit the loss of life and ensure \"collapse prevention\" for such\nlarge earthquakes, but not necessarily limit damage. Unfortunately, widespread closures such as this could cripple the\nregional economy in the event of such an earthquake.\nA second scenario considered in the study involves the same Denali earthquake source mapped to the San Andreas\nfault but with rupture initiating in the south and propagating to the north (with the largest amount of slip occurring to\nthe north in Central California) instead of the other way around. The results of such a scenario indicate that ground\nshaking would be far less severe demonstrating the effects of directivity and slip distribution in dictating the level of\nground shaking and the associated damage in buildings. The peak drifts in existing and redesigned building models\nare in the range of 0.02-0.04 indicating that there is no signicant danger of collapse. However, damage would still\nbe signicant enough to warrant building closures and compromise life safety in some instances.\nThe ground motion simulation and the structural damage modeling procedures are validated using data from the\nJanuary 17, 1994, Northridge earthquake while the band-limited nature of the ground motion simulation (limited to\na shortest period of 2 s by the current state of knowledge of the 3-D Earth structure) is shown to have no signicant\neffect on the response of the two tall buildings considered here with the use of observed records from the 1999 Chi\nChi earthquake in Taiwan and the 2001 Tokachi-Oki earthquake in Japan.", "date": "2005-07-29", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2005-01.1010", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2005-01.1010", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2005_01.pdf", "url": "https://authors.library.caltech.edu/records/4qemw-m0q51/files/EERL2005_01.pdf" }, "pub_year": "2005", "author_list": "Krishnan, Swaminathan; Ji, Chen; et el." }, { "id": "https://authors.library.caltech.edu/records/fwe6b-q1g50", "eprint_id": 26264, "eprint_status": "archive", "datestamp": "2023-09-14 19:11:15", "lastmod": "2024-01-13 05:29:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "May-Bennett-Scott", "name": { "family": "May", "given": "B. Scott" } }, { "id": "Polidori-D-C", "name": { "family": "Polidori", "given": "David C." } }, { "id": "Vanik-M-W", "name": { "family": "Vanik", "given": "Michael W." } } ] }, "title": "Ambient vibration studies of three steel-frame buildings strongly shaken by the 1994 Northridge earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - EERL-95-06.pdf
", "abstract": "Ambient vibration surveys (AVS) can be used efficiently, cheaply and unobtrusively to identify the small-amplitude periods and modeshapes of lower modes of vibration of structures. Under Task 3.2 of Phase I of the SAC Steel Building Program, AVS were performed on three steel-frame buildings which experienced strong shaking during the January 17, 1994 Northridge earthquake. \nThe primary objective of this study was to identify the small-amplitude modal parameters of the building for assessment of the analytical models constructed by others under SAC Task 3.1. A preliminary comparison of the modal periods obtained from the AVS with those calculated form the analytical models is presented. Although the periods identified from the AVS were considerably shorter than the model periods, the ratios of the identified to model periods for each mode were quite similar. The differences in periods are thought to be primarily because the analytical models treat only the structural frame, ignoring the stiffness of nonstructural components such as architectural partitions and building cladding. \n \nThis study also serves as a first step in the testing of proposed structural health monitoring methodologies. Since one of the tested steel-frame buildings was damaged and has not yet been repaired, its data represent an \"after\" damage state. The tests on this steel-frame building can be followed later by an AVS if the structure is repaired. These \"before\" and \"after\" AVS results would provide valuable data to test proposed global structural health monitoring methodologies whose goal is to detect, locate and assess damage by monitoring ambient vibrations. A successful structural health monitoring method would allow \"hidden\" damage to be detected almost immediately rather than weeks after an earthquake.", "date": "2005-05-06", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-95-06.pdf", "url": "https://authors.library.caltech.edu/records/fwe6b-q1g50/files/EERL-95-06.pdf" }, "pub_year": "2005", "author_list": "Beck, James L.; May, B. Scott; et el." }, { "id": "https://authors.library.caltech.edu/records/wmbkp-zw586", "eprint_id": 26552, "eprint_status": "archive", "datestamp": "2023-08-19 11:28:18", "lastmod": "2024-01-13 05:31:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Camelo-Vanessa-Sabrina", "name": { "family": "Camelo", "given": "Vanessa Sabrina" } } ] }, "title": "Dynamic Characteristics of Woodframe Buildings", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2003\n\nAccepted Version - EERL2003-04.pdf
", "abstract": "A database of dynamic characteristics of woodframe buildings was developed through analysis of recorded earthquake response and by forced vibration and shaketable\ntesting. Modal identification was performed on eight sets of strong-motion records obtained from five buildings, and forced vibration tests were performed on five other buildings. The periods identified were sensitive to the amplitude of shaking, due to the reduction in lateral stiffness at stronger shaking levels. The equivalent\nviscous damping ratios were usually more than 10% of critical during earthquake shaking. A regression analysis was performed on the earthquake and forced vibration\ntest data to obtain a simple, but reasonably accurate, period formula for woodframe\nbuildings at low drift levels (less than 0.1%). Data obtained from the UC San Diego\nand UC Berkeley full-scale shake-table tests illustrate the shift in periods due to increasing\nshaking amplitude. Forced vibration tests of the UC Berkeley 3-story building\nbefore and after the shake-table tests showed how the periods and modeshapes\nshift due to damage. A simple analytical model of masses and springs was used to\nmodel the UC Berkeley test structure. The effects of diaphragm stiffness and mass\ndistribution assumptions were evaluated and found to have a significant effect on the\nmodel torsional response. This model was used to find the equivalent wall stiffnesses\ngiving frequency-response curves that best-fit the experimental data. These spring\nvalues were used to quantify the stiffness loss resulting from severe shaking of the\nstructure, and the observed damage corresponded to stiffness losses of over 75%. The\ncorrelation between stiffness loss and damage to woodframe buildings has potential\nstructural health monitoring implications.", "date": "2005-02-10", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2003-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2003-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2003-04.pdf", "url": "https://authors.library.caltech.edu/records/wmbkp-zw586/files/EERL2003-04.pdf" }, "pub_year": "2005", "author_list": "Camelo, Vanessa Sabrina" }, { "id": "https://authors.library.caltech.edu/records/ddnzs-9y573", "eprint_id": 26549, "eprint_status": "archive", "datestamp": "2023-08-19 13:19:27", "lastmod": "2024-01-13 05:31:34", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Clinton-J-F", "name": { "family": "Clinton", "given": "John F." }, "orcid": "0000-0001-8626-2703" } ] }, "title": "Modern Digital Seismology: Instrumentation, and Small Amplitude Studies in the Engineering World", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2004\n\nAccepted Version - EERL2004-10.pdf
", "abstract": "The recording of ground motions is a fundamental part of both seismology and earthquake\nengineering. The current state-of-the-art 24-bit continuously recording seismic station is\ndescribed, with particular attention to the frequency range and dynamic range of the seismic\nsensors typically installed. An alternative method of recording the strong-motions would be\nto deploy a velocity sensor rather than an accelerometer. This instrument has the required\nability to measure the strongest earth motions, with enhanced long period sensitivity.\nAn existing strong motion velocity sensor from Japan was tested for potential use in US\nseismic networks. It was found to be incapable of recording strong motions typically observed\nin the near field of even moderate earthquakes. The instrument was widely deployed\nnear the M8.3 Sept 2003 Tokachi-Oki earthquake. The dataset corroborated our laboratory\nobservations of low velocity saturations. The dataset also served to show all inertial sensors\nare equally sensitive to tilting, which is widespread in large earthquakes. High-rate\nGPS data is also recorded during the event. Co-locating high-rate GPS with strong motion\nsensors is suggested to be currently the optimal method by which the complete and\nunambiguous deformation field at a station can be recorded.\nA new application of the modern seismic station is to locate them inside structures. A\ntest station on the 9th floor of Millikan Library is analysed. The continuous data-stream\nfacilitates analysis of the building response to ambient weather, forced vibration tests, and\nsmall earthquakes that have occurred during its lifetime. The structure's natural frequencies\nare shown to be sensitive not only to earthquake excitation, but rainfall, temperature and\nwind. This has important implications on structural health monitoring, which assumes the\nnatural frequencies of a structure do not vary significantly unless there is structural damage.\nModerate to small earthquakes are now regularly recorded by dense, high dynamic\nrange networks. This enhanced recording of the earthquake and its aftershock sequences\nmakes possible the development of a Green's Function deconvolution approach for determining\nrupture parameters.", "date": "2004-10-19", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-10", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-10", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-10.pdf", "url": "https://authors.library.caltech.edu/records/ddnzs-9y573/files/EERL2004-10.pdf" }, "pub_year": "2004", "author_list": "Clinton, John F." }, { "id": "https://authors.library.caltech.edu/records/zfdym-0g464", "eprint_id": 26551, "eprint_status": "archive", "datestamp": "2023-08-19 14:26:06", "lastmod": "2024-01-13 05:31:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alves-Steven-Wayne", "name": { "family": "Alves", "given": "Steven Wayne" } } ] }, "title": "Nonlinear Analysis of Pacoima Dam with Spatially Nonuniform Ground Motion", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2005", "abstract": "Spatially uniform ground motion is an assumption that has often been made for\nstructural analysis of arch dams. However, it has been recognized for many years\nthat the ground motion in a canyon during an earthquake is amplified at the top\nof the canyon relative to the base. Pacoima Dam has been strongly shaken by the\n1971 San Fernando earthquake and the 1994 Northridge earthquake. The acceleration\nrecords from both of these events demonstrate the spatial nonuniformity of the ground\nmotion, but the amount and quality of the data made it difficult to study in detail. An\nopportunity to do so arose on January 13, 2001, when a relatively small magnitude 4.3\nearthquake was recorded by an upgraded accelerometer array at Pacoima Dam.\nFrequency-dependent topographic amplification is apparent at locations along\nboth abutments at 80% height of the dam relative to the base. Also, the ground\nmotion is delayed at the abutment locations compared to the base. The delays are\nconsistent with seismic waves traveling upward along the canyon, and the waves appear\nto be dispersive since the delays are frequency-dependent. Both of these effects\nare quantified in this thesis by several approaches that involve varying degrees of\napproximation. A method for generating nonuniform ground motion from a single\n3-component ground motion specified for one location in the canyon, e.g., at the base,\nis developed using transfer functions that quantify the amplification and phase delay.\nThe method is demonstrated for the 2001 earthquake and the Northridge earthquake\nwith several variations in the transfer functions.\nThe 2001 earthquake records were also used for system identification. These results\ndo not agree with results from a forced vibration experiment, which indicate a\nstiffer system. The earthquake must induce nonlinear vibrations, even though the excitation is quite small. This observation has implications for applications of structural\nhealth monitoring.\nThe generated nonuniform ground motions are supplied as input to a finite element\nmodel. The results indicate that the method for generating nonuniform input\nproduces ground motion that yields reasonable modeled responses, but there is some\nevidence that the time delays may be larger for stronger ground motion. Comparisons\nof the responses from ground motions generated with various implementations\nof amplification and time delays were made. For modeling purposes, accuracy of\nthe amplification appears to be more important than the delays, which can be dealt\nwith using a simpler approximation. The nonuniform input produces a response that\nis substantially different than the response produced by uniform input. The major\ndifference is that while the pseudostatic response is a rigid body motion for uniform\ninput, it causes deformation of the dam, mostly close to the abutments, for\nnonuniform input. In order to refine the proposed method for generating nonuniform\nground motion, more data is required from Pacoima Dam and other structures with\ninstrumentation coverage along the abutments.", "date": "2004-10-07", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-11", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-11", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-11.pdf", "url": "https://authors.library.caltech.edu/records/zfdym-0g464/files/EERL2004-11.pdf" }, "pub_year": "2004", "author_list": "Alves, Steven Wayne" }, { "id": "https://authors.library.caltech.edu/records/3d6wr-tsy20", "eprint_id": 26545, "eprint_status": "archive", "datestamp": "2023-08-19 14:09:27", "lastmod": "2024-01-13 05:31:31", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Ching-Jianye", "name": { "family": "Ching", "given": "Jianye" }, "orcid": "0000-0001-6028-1674" }, { "id": "Mitrani-Reiser-Judith", "name": { "family": "Mitrani-Reiser", "given": "Judith" } }, { "id": "Miyamura-M", "name": { "family": "Miyamura", "given": "M." } }, { "id": "Kusaka-A", "name": { "family": "Kusaka", "given": "A." } }, { "id": "Kudo-T", "name": { "family": "Kudo", "given": "T." } }, { "id": "Ikkatai-K", "name": { "family": "Ikkatai", "given": "K." } }, { "id": "Hyodo-Y", "name": { "family": "Hyodo", "given": "Y." } } ] }, "title": "Real-time Loss Estimation for Instrumented Buildings", "ispublished": "unpub", "full_text_status": "public", "note": "A report on research supported by the CUREE-Kajima Joint Research Program Phase V under the supervision of K.A. Porter and J.L. Beck", "abstract": "Motivation. A growing number of buildings have been instrumented to measure and record\nearthquake motions and to transmit these records to seismic-network data centers to be archived and\ndisseminated for research purposes. At the same time, sensors are growing smaller, less expensive to\ninstall, and capable of sensing and transmitting other environmental parameters in addition to\nacceleration. Finally, recently developed performance-based earthquake engineering methodologies\nemploy structural-response information to estimate probabilistic repair costs, repair durations, and\nother metrics of seismic performance. The opportunity presents itself therefore to combine these\ndevelopments into the capability to estimate automatically in near-real-time the probabilistic seismic\nperformance of an instrumented building, shortly after the cessation of strong motion. We refer to\nthis opportunity as (near-) real-time loss estimation (RTLE).\nMethodology. This report presents a methodology for RTLE for instrumented buildings. Seismic\nperformance is to be measured in terms of probabilistic repair cost, precise location of likely physical\ndamage, operability, and life-safety. The methodology uses the instrument recordings and a Bayesian\nstate-estimation algorithm called a particle filter to estimate the probabilistic structural response of\nthe system, in terms of member forces and deformations. The structural response estimate is then\nused as input to component fragility functions to estimate the probabilistic damage state of structural\nand nonstructural components. The probabilistic damage state can be used to direct structural\nengineers to likely locations of physical damage, even if they are concealed behind architectural\nfinishes. The damage state is used with construction cost-estimation principles to estimate\nprobabilistic repair cost. It is also used as input to a quantified, fuzzy-set version of the FEMA-356\nperformance-level descriptions to estimate probabilistic safety and operability levels.\nCUREE demonstration building. The procedure for estimating damage locations, repair costs, and\npost-earthquake safety and operability is illustrated in parallel demonstrations by CUREE and\nKajima research teams. The CUREE demonstration is performed using a real 1960s-era, 7-story, nonductile\nreinforced-concrete moment-frame building located in Van Nuys, California. The building is\ninstrumented with 16 channels at five levels: ground level, floors 2, 3, 6, and the roof. We used the\nrecords obtained after the 1994 Northridge earthquake to hindcast performance in that earthquake.\nThe building is analyzed in its condition prior to the 1994 Northridge Earthquake. It is found that,\nwhile hindcasting of the overall system performance level was excellent, prediction of detailed damage\nlocations was poor, implying that either actual conditions differed substantially from those shown on\nthe structural drawings, or inappropriate fragility functions were employed, or both. We also found\nthat Bayesian updating of the structural model using observed structural response above the base of\nthe building adds little information to the performance prediction. The reason is probably that\nReal-Time Loss Estimation for Instrumented Buildings\nii\nstructural uncertainties have only secondary effect on performance uncertainty, compared with the\nuncertainty in assembly damageability as quantified by their fragility functions. The implication is\nthat real-time loss estimation is not sensitive to structural uncertainties (saving costly multiple\nsimulations of structural response), and that real-time loss estimation does not benefit significantly\nfrom installing measuring instruments other than those at the base of the building.\nKajima demonstration building. The Kajima demonstration is performed using a real 1960s-era\noffice building in Kobe, Japan. The building, a 7-story reinforced-concrete shearwall building, was not\ninstrumented in the 1995 Kobe earthquake, so instrument recordings are simulated. The building is\nanalyzed in its condition prior to the earthquake. It is found that, while hindcasting of the overall\nrepair cost was excellent, prediction of detailed damage locations was poor, again implying either that\nas-built conditions differ substantially from those shown on structural drawings, or that\ninappropriate fragility functions were used, or both. We find that the parameters of the detailed\nparticle filter needed significant tuning, which would be impractical in actual application. Work is\nneeded to prescribe values of these parameters in general.\nOpportunities for implementation and further research. Because much of the cost of applying\nthis RTLE algorithm results from the cost of instrumentation and the effort of setting up a structural\nmodel, the readiest application would be to instrumented buildings whose structural models are\nalready available, and to apply the methodology to important facilities. It would be useful to study\nunder what conditions RTLE would be economically justified. Two other interesting possibilities for\nfurther study are (1) to update performance using readily observable damage; and (2) to quantify the\nvalue of information for expensive inspections, e.g., if one inspects a connection with a modeled 50%\nfailure probability and finds that the connect is undamaged, is it necessary to examine one with 10%\nfailure probability?", "date": "2004-09", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-08", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-08", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-08.pdf", "url": "https://authors.library.caltech.edu/records/3d6wr-tsy20/files/EERL2004-08.pdf" }, "pub_year": "2004", "author_list": "Porter, Keith A.; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/8v44r-29b44", "eprint_id": 26544, "eprint_status": "archive", "datestamp": "2023-08-19 14:03:36", "lastmod": "2023-10-24 16:23:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } } ] }, "title": "A Survey of Bridge Practitioners to Relate Damage to Closure", "ispublished": "unpub", "full_text_status": "public", "abstract": "The Pacific Earthquake Engineering Research (PEER) Center's second-generation performance-based earthquake engineering (PBEE) methodology is intended in part to model highway bridge performance in terms of collapse, closure, repair duration, speed or load limitations, and possibly other performance measures. Some of these are difficult to model, particularly closure decisions where the engineering evidence of safety is inconclusive and must be supplemented by the inspector's judgment. This paper presents results of a limited, initial survey of department of transportation (DOT) engineers' beliefs about the relationship between physical damage and closure. The initial survey addresses a common class of reinforced-concrete bridges. The author and others developed and administered to a select, nationwide group of DOT engineers a one-page, multiple-choice survey form with expert self-rating, asking the engineers to relate ten damage measures (DM) to four closure levels. The DMs include approach settlement, offsets at abutments and expansion joints, flexural and shear cracks in beams, columns, shear keys, and backwalls. The performance levels considered are: leave open, close briefly for quick repairs, close for an extended period, and reduce speed. The survey results are analyzed to produce a number of preliminary relationships between damage and post-earthquake decisions by inspectors, relationships that can be used in probabilistic seismic performance evaluation in PEER's developing PBEE methodology. This preliminary test of a survey form also yielded insight into a number of desirable improvements for a second round of survey, possibly to be administered via the Internet early in 2004.", "date": "2004-08-01", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-07.pdf", "url": "https://authors.library.caltech.edu/records/8v44r-29b44/files/EERL2004-07.pdf" }, "pub_year": "2004", "author_list": "Porter, Keith A." }, { "id": "https://authors.library.caltech.edu/records/y1b4r-56x30", "eprint_id": 26550, "eprint_status": "archive", "datestamp": "2023-08-19 13:42:23", "lastmod": "2023-10-24 16:23:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Scruggs-J-T", "name": { "family": "Scruggs", "given": "Jeffrey T." } } ] }, "title": "Structural Control Using Regenerative Force Actuation Networks", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2004", "abstract": "A Regenerative Force Actuation (RFA) Network consists of multiple electromechanical\nforcing devices distributed throughout a structural system and actuated in such a way as to reduce\nthe response of the structure when subject to an excitation. The associated electronics of the\ndevices are connected together such that they are capable of sharing electrical power with each\nother. This makes it possible for some devices to extract mechanical energy from the structure,\nwhile others re-inject a portion of that energy back into the structure at other locations. The\nforcing capability of an RFA network is constrained only by the requirement that in the aggregate\nthe total network must always dissipate energy.\nThe electromechanical currents generated by RFA networks must be controlled to create\nthe desired structural forces. This control is facilitated by the alternation of a multitude of powerelectronic\ntransistor switches in the electrical network. In this study, a sliding-mode switching\ncontroller is proposed for realizing zero-error force command tracking. It is shown that\nparameter uncertainty is a critical issue for force commands which require the network to operate\nnear its optimum transmissive efficiency.\nRFA networks can be used to create velocity-proportional damping forces in structures.\nHowever, unlike traditional structural damping, RFA networks have the ability to create non-local\nand asymmetric damping forces. It is shown that this more generalized damping capability can\nlead to significant improvements in the forced response of a structure, as compared with\ntraditional linear damping.\nRFA networks may also be used for feedback control. In this context, the forcing\ncapability of the RFA network is constrained by its physical limitations. In this study, a\nsystematic method of nonlinear control design called \"Damping-Reference\" control is proposed,\nwhich guarantees a certain level of quadratic performance for the structural response. Variants of\nthe control law synthesis are proposed for quadratic regulation, stochastic control, and H\u221e control\ncontexts.\nThese ideas are illustrated in the context of earthquake engineering through a simulation\nexample, involving a three-story structure with a two-actuator RFA network installed. In this\nexample, it is shown that the \"power sharing\" nature of the RFA network has a significant\ninfluence on the response.", "date": "2004-06-01", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-09", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-09", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-09_1.pdf", "url": "https://authors.library.caltech.edu/records/y1b4r-56x30/files/EERL2004-09_1.pdf" }, "related_objects": [ { "basename": "EERL2004-09_2.pdf", "url": "https://authors.library.caltech.edu/records/y1b4r-56x30/files/EERL2004-09_2.pdf" }, { "basename": "EERL2004-09_3.pdf", "url": "https://authors.library.caltech.edu/records/y1b4r-56x30/files/EERL2004-09_3.pdf" } ], "pub_year": "2004", "author_list": "Scruggs, Jeffrey T." }, { "id": "https://authors.library.caltech.edu/records/90v2p-gzj64", "eprint_id": 26548, "eprint_status": "archive", "datestamp": "2023-08-19 13:34:17", "lastmod": "2023-10-24 16:23:48", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaikhutdinov-R-V", "name": { "family": "Shaikhutdinov", "given": "R. V." } } ] }, "title": "Structural Damage Evaluation: Theory and Applications to Earthquake Engineering", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2004", "abstract": "The further development of performance-based earthquake engineering (PBEE) is on the current agenda of the earthquake engineering community. A part of assessing the seismic performance of civil engineering structures involves estimation of seismic damage. The conventional approach to damage estimation is based on fragility functions that relate some chosen parameters of structural response to incurred damage. Therefore, damage prediction is based exclusively on the knowledge of the chosen structural response parameters, meaning that damage analysis is uncoupled from the structural analysis. The structural response parameters selected for use in damage analysis are usually referred to as engineering demand parameters (EDP). In the present study, it is shown that for structural damage estimation, the uncoupled damage analysis has deficiencies that lead to less accurate damage prediction. These shortcomings originate from two sources: first, dependence of practically all EDPs on structural damage and second, inexact damage description. To overcome these deficiencies, another approach to structural damage estimation is proposed. The proposed approach, besides using an EDP, uses all information available from structural analysis that is relevant to the damage to be assessed, implying that damage analysis is coupled with structural analysis. It is shown\nthat utilization of this additional information provides more accurate damage prediction.\nThe difference between the two approaches is studied by comparison of results of damage estimation performed for a 2-D structural model of a reinforced-concrete frame. The results show that difference between uncoupled and coupled damage analysis estimates could be significant and that it depends on specific characteristics of the chosen structural model and the damage model in a complex way, preventing the possibility of estimating this error in a general form that is applicable to all practically possible cases. Damage estimation is performed for various damage models that include both single and multiple damage states. Since the final goal of seismic performance evaluation is estimation of decision variables such as repair cost, downtime, etc., the two approaches to damage estimation are also compared in terms of repair cost that is calculated for the\nreinforced-concrete frame. A case where structural damage prediction is based on observation of EDP alone, without a structural model available, is also studied. It is shown that incorporating site-specific information can significantly change the damage estimates and, therefore, may be worth doing.", "date": "2004-05-01", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.\n", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-06.pdf", "url": "https://authors.library.caltech.edu/records/90v2p-gzj64/files/EERL2004-06.pdf" }, "pub_year": "2004", "author_list": "Shaikhutdinov, R. V." }, { "id": "https://authors.library.caltech.edu/records/9veed-jtv38", "eprint_id": 26546, "eprint_status": "archive", "datestamp": "2023-08-19 13:19:16", "lastmod": "2024-01-13 05:31:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guyader-Andrew-Charles", "name": { "family": "Guyader", "given": "Andrew" } } ] }, "title": "A Statistical Approach to Equivalent Linearization with Applications to Performance-Based Engineering", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2003; A report on research supported by the California Institute of Technology under the supervision of Wilfred D. Iwan", "abstract": "A new methodology for calculating optimal effective linear parameters for use in predicting the earthquake response of structures is developed. The methodology is applied to several single-degree-of-freedom inelastic structural models subjected to a suite of earthquake acceleration time histories. Separately, far-field and near-field earthquakes are analyzed. Error distributions over a two-dimensional parameter space of period and damping are analyzed through a statistical approach with optimization criterion most applicable to structural design. Four hysteretic models are analyzed: bilinear, stiffness degrading, strength degrading and pinching. Initial structural periods are analyzed in groups for several second slope ratios (...) at different levels of ductility. It was discovered that as ductility increases, the accuracy of the effective parameters decrease but the consequences of bad parameter selection become less\nsevere.\nThe new effective parameters are intended for use in displacement-based structural analysis procedures as used in Performance-Based Engineering. Of the several procedures available, Nonlinear Static Procedures, such as the Capacity Spectrum Method, are widely used by structural engineers because the nonlinear characteristics of both structural components and the global structure are utilized without running a nonlinear time history analysis. Effective linear parameters are used in the Capacity Spectrum Method to calculate the expected displacement demand, or Performance\nPoint, for a structure. Because several sources of error exist within the Capacity Spectrum Method, an analysis that isolates the error from the effective linear parameters is\nperformed. The new effective linear parameters show considerable improvement over the existing effective linear equations. The existing linear parameters are extremely\nunconservative at the lower ductilities and conservative at the higher ductilities. The new parameters lead to a significant improvement in both cases. \nA modification to the Capacity Spectrum Method is introduced to account for the new effective linear period. Currently, the Capacity Spectrum Method uses the secant period as the effective linear period. The modification preserves the basic Performance Point calculation. Finally, a new, entirely graphical solution procedure using a Locus\nof Performance Points provides crucial insight into the effects of strengthening, stiffening and increasing building ductility not available in the current procedure.", "date": "2004-04", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-04.pdf", "url": "https://authors.library.caltech.edu/records/9veed-jtv38/files/EERL2004-04.pdf" }, "pub_year": "2004", "author_list": "Guyader, Andrew" }, { "id": "https://authors.library.caltech.edu/records/yn0aa-vs646", "eprint_id": 26547, "eprint_status": "archive", "datestamp": "2023-08-19 13:19:21", "lastmod": "2023-10-24 16:23:45", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guyader-Andrew-Charles", "name": { "family": "Guyader", "given": "Andrew" } }, { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "User Guide for AutoCSM: Automated Capacity Spectrum Method of Analysis", "ispublished": "unpub", "full_text_status": "public", "note": "A report on research supported by the California Institute of Technology under the supervision of W.D. Iwan.", "abstract": "No Abstract Submitted", "date": "2004-04", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:EERL-2004-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL2004-05.pdf", "url": "https://authors.library.caltech.edu/records/yn0aa-vs646/files/EERL2004-05.pdf" }, "pub_year": "2004", "author_list": "Guyader, Andrew and Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/jng5h-hfd57", "eprint_id": 26541, "eprint_status": "archive", "datestamp": "2023-08-19 10:30:42", "lastmod": "2024-01-13 05:31:29", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" } ] }, "title": "FRAME3D - A Program for Three-Dimensional Nonlinear Time- History Analysis of Steel Buildings: User Guide", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - EERL_2003_03.pdf
", "abstract": "FRAME3D is a program for the three-dimensional nonlinear analysis of steel buildings. It aims to overcome the computational challenges posed by full 3D analysis of buildings subject to earthquake ground motion. The element library consists of a plastic hinge beam element, an elastofiber beam element, a panel zone element, a 4-noded diaphragm element to model floor slabs, and an elastic translational/rotational spring element to model foundations and supports. The program utilizes a Netwon-Raphson iteration strategy applied to an implicit Newmark time-integration scheme to solve the nonlinear equations of motion at each time-step. Geometric nonlinearity and shear deformation are included in the formulation. This document serves as a User Guide to the program. All the input and output variables encountered by the user are described here along with brief descriptions of the various types of elements. In addition, 2 examples illustrating the capabilities and usage of the program are presented. Finally a glossary of all the variables is alphabetically listed at the end of the document for the user's convenience.", "date": "2004-02-24", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2003-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2003-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2003_03.pdf", "url": "https://authors.library.caltech.edu/records/jng5h-hfd57/files/EERL_2003_03.pdf" }, "pub_year": "2004", "author_list": "Krishnan, Swaminathan" }, { "id": "https://authors.library.caltech.edu/records/2d3cf-80f88", "eprint_id": 26557, "eprint_status": "archive", "datestamp": "2023-08-19 13:03:18", "lastmod": "2023-10-24 16:24:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ching-J", "name": { "family": "Ching", "given": "Jianye" } }, { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "Uncertainty Propagation and Feature Selection for Loss Estimation in Performance-based Earthquake Engineering", "ispublished": "unpub", "full_text_status": "public", "note": "Published - EERL-2004-02.pdf
", "abstract": "This report presents a new methodology, called moment matching, of propagating the uncertainties in estimating repair costs of a building due to future earthquake excitation, which is required, for example, when assessing a design in performance-based earthquake engineering. Besides excitation uncertainties, other uncertain model variables are considered, including uncertainties in the structural model parameters and in the capacity and repair costs of structural and non-structural components. Using the first few moments of these uncertain variables, moment matching requires only a few well-chosen point estimates to propagate the uncertainties to estimate the first few moments of the repair costs with high accuracy. Furthermore, the use of moment matching to estimate the exceedance probability of the repair costs is also addressed. These examples illustrate that the moment-matching approach is quite general; for example, it can be applied to any decision variable in performance-based earthquake engineering.\nTwo buildings are chosen as illustrative examples to demonstrate the use of moment matching, a hypothetical three-story shear building and a real seven-story hotel building. For these two examples, the assembly-based vulnerability approach is employed when calculating repair costs. It is shown that the moment-matching technique is much more accurate than the well-known First-Order-Second-Moment approach when propagating the first two moments, while the resulting computational cost is of the same order. The repair-cost moments and exceedance probability estimated by the moment-matching technique are also compared with those by Monte Carlo simulation. It is concluded that as long as the order of the moment matching is sufficient, the comparison is satisfactory. Furthermore, the amount of computation for moment matching scales only linearly with the number of uncertain input variables.\nLast but not least, a procedure for feature selection is presented and illustrated for the second example. The conclusion is that the most important uncertain input variables among the many influencing the uncertainty in future repair costs are, in order of importance, ground-motion spectral acceleration, component capacity, ground-motion details and unit repair costs.", "date": "2004-02", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2004-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-2004-02.pdf", "url": "https://authors.library.caltech.edu/records/2d3cf-80f88/files/EERL-2004-02.pdf" }, "pub_year": "2004", "author_list": "Ching, Jianye; Porter, Keith A.; et el." }, { "id": "https://authors.library.caltech.edu/records/8fa04-4wr13", "eprint_id": 26543, "eprint_status": "archive", "datestamp": "2023-08-19 12:55:14", "lastmod": "2023-10-24 16:23:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ching-J", "name": { "family": "Ching", "given": "Jianye" } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Shaikhutdinov-R-V", "name": { "family": "Shaikhutdinov", "given": "Rustem" } } ] }, "title": "Real-time Bayesian State Estimation of Uncertain Dynamical Systems", "ispublished": "unpub", "full_text_status": "public", "note": "Published - EERL200401.pdf
", "abstract": "The focus of this report is real-time Bayesian state estimation using nonlinear models. A recently developed method, the particle filter, is studied that is based on Monte Carlo simulation. Unlike the well-known extended Kalman filter, it is applicable to highly nonlinear systems with non-Gaussian uncertainties. Recently developed techniques that improve the convergence of the particle filter simulations are also introduced and discussed. Comparisons between the particle filter and the extended Kalman filter are made using several numerical examples of nonlinear systems. The results indicate that the particle filter provides consistent state and parameter estimates for highly nonlinear systems, while the extended Kalman filter does not.\nThe particle filter is applied to a real-data case study: a 7-story hotel whose structural system consists of non-ductile reinforced-concrete moment frames, one of which was severely damaged during the 1994 Northridge earthquake. Two identification models are proposed: a timevarying linear model and a simplified time-varying nonlinear degradation model. The latter is derived from a nonlinear finite-element model of the building previously developed at Caltech. For the former model, the resulting performance is poor since the parameters need to vary significantly with time in order to capture the structural degradation of the building during the earthquake. The latter model performs better because it is able to characterize this degradation to a certain extent even with its parameters fixed. Once again, the particle filter provides consistent state and parameter estimates, in contrast to the extended Kalman filter. It is concluded that for a state estimation procedure to be successful, at least two factors are essential: an appropriate estimation algorithm and a suitable identification model. Finally, recorded motions from the 1994 Northridge earthquake are used to illustrate how to do real-time performance evaluation by computing estimates of the repair costs and probability of component damage for the hotel.", "date": "2004-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2004-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2004-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL200401.pdf", "url": "https://authors.library.caltech.edu/records/8fa04-4wr13/files/EERL200401.pdf" }, "pub_year": "2004", "author_list": "Ching, Jianye; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/rz73s-dxb56", "eprint_id": 26540, "eprint_status": "archive", "datestamp": "2023-08-19 12:00:01", "lastmod": "2024-01-13 05:31:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krishnan-Swaminathan", "name": { "family": "Krishnan", "given": "Swaminathan" }, "orcid": "0000-0002-2594-1523" } ] }, "title": "Three-Dimensional Nonlinear Analysis of Tall Irregular Steel Buildings Subject to Strong Ground Motion", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2004\n\nAccepted Version - EERL_2003_01.pdf
", "abstract": "Strong ground motion from a nearby fault has frequency content in the same range as the natural frequencies of tall buildings. This may have serious repercussions and is the topic of this dissertation.\nBuildings are designed per building code standards. But, are the code provisions adequate? Strong motion from large earthquakes has been recorded only in recent times in the near-source region. Have the current codes used this information to update tall structure design guidelines? Considerable damage has been observed in tall buildings from the Northridge, Kobe, Turkey, and Taiwan earthquakes. How will tall buildings designed per the latest code regulations perform if they were to be shaken by any of these earthquakes? This thesis attempts to answer these questions.\n\nTall buildings by their nature are computationally intensive to analyze. They consist of thousands of degrees of freedom and when subjected to strong ground motion from a nearby source, exhibit inelastic response. Modeling this inelastic response requires an iterative approach that is computationally expensive. Furthermore, a large class of buildings, classified as irregular, exhibits complex behavior that can be studied only when the structures are modeled in their entirety. To this end, a three-dimensional analysis program, FRAME3D, has been developed incorporating two special beam-column elements -- the plastic hinge element and the elastofiber element that can model beams and columns in buildings accurately and efficiently, a beam-column joint element that can model inelastic joint deformation, and 4-noded elastic plane-stress elements to model floor slabs acting as diaphragms forcing the lateral force resisting frames in a building to act as one unit. The program is capable of performing time-history analyses of buildings in their entirety.\n\nSix 19-story irregular steel moment frame buildings (with buildings 2A and 3A being variants of buildings 2 and 3, respectively) have been designed per the latest code (Uniform Building Code, 1997). Two of these buildings have reentrant corners and the other two have torsional irregularity. Their strength and ductility are assessed by performing pushover analyses on them. To assess their performance under strong shaking, FRAME3D models of these buildings are subjected to near-source strong motion records from the Iran earthquake (M[subscript w] = 7.3, Tabas Station) of 1978, the Northridge earthquake (M[subscript w] = 6.7, Sylmar Station) of 1994 and the Kobe earthquake (M[subscript w] = 6.9, Takatori\nStation) of 1995. None of the buildings collapsed under these strong events in the computer analyses. However, when compared against the acceptable limits for various performance levels in FEMA 356 document, the damage in terms of plastic deformation at the ends of beams and columns and at joints would render the buildings inadequate in terms of life safety in quite a few cases and would even indicate possible collapse in a couple of cases. Thus, in these terms, the code falls short of achieving its life safety objective, and the near-source factors introduced in the code in 1997 in recognition of the special features of near-source ground motion seem to be inadequate.\n\nThe ductility demand, in terms of plastic rotation at the ends of beams and columns and in joints, on these buildings during this class of earthquakes is up to 6% of a radian, which is far greater than a typical limiting plastic rotation of 3% associated with fracture and consequent failure of large wide-flanged steel sections during experiments. Thus, if strength degradation due to fractures, local buckling, etc., were to be included in the analysis, then the results would likely to be worse, as far as the ability of these buildings to withstand these earthquakes without collapse is concerned.\n\nDue to damage localization, the peak drifts observed in the structure far exceeded the inelastic drift limit in the code of 0.02 (in some cases up to 3 times). This points to serious non-structural damage to facades, interior dry wall, etc. Furthermore, large roof permanent offsets after the events indicate significant post-earthquake repair requiring considerable disruption and building closure.\n\nColumn yielding was minimal thus validating the strong-column weak-beam criterion in the code. Redundancy factors used to assess the redundancy in the system need to take into account the case of torsionally sensitive structures where frames in both principal directions are simultaneously activated. Stress concentration was not observed at the reentrant corners in L-shaped buildings.\n\nFinally, the data catalogued in this work could be useful for future code development and tall structure design guidelines.", "date": "2003-09-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL-2003-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL-2003-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL_2003_01.pdf", "url": "https://authors.library.caltech.edu/records/rz73s-dxb56/files/EERL_2003_01.pdf" }, "pub_year": "2003", "author_list": "Krishnan, Swaminathan" }, { "id": "https://authors.library.caltech.edu/records/zwspz-3g568", "eprint_id": 26538, "eprint_status": "archive", "datestamp": "2023-08-19 10:47:14", "lastmod": "2023-10-24 16:23:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ching-J", "name": { "family": "Ching", "given": "Jianye" } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "Two-step Bayesian Structure Health Monitoring Approach for IASC-ASCE Phase II Simulated and Experimental Benchmark Studies", "ispublished": "unpub", "full_text_status": "public", "abstract": "This report uses a two-step probabilistic structural health monitoring approach to analyze the Phase II simulated and experimental benchmark studies sponsored by the IASC-ASCE Task Group on Structural Health Monitoring. The studies involve damage detection and assessment of the test structure using simulated ambient-vibration data and experimental data generated by various excitations. The two-step approach involves modal identification followed by damage assessment using the pre- and post-damage modal parameters based on the Bayesian updating methodology. An Expectation-Maximization algorithm is proposed to find the most probable values of the parameters. The results of the analysis show that the probabilistic approach is able to detect and assess most damage locations involving stiffness losses of braces in the braced frame cases, while the success of the approach in detecting rotational stiffness losses of the beam-column connections in the untraced cases may rely on sufficient prior information for the column stiffness.", "date": "2003-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2003.EERL-2003-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:2003.EERL-2003-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL200302.pdf", "url": "https://authors.library.caltech.edu/records/zwspz-3g568/files/EERL200302.pdf" }, "pub_year": "2003", "author_list": "Ching, Jianye and Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/vcyn6-yeb92", "eprint_id": 26442, "eprint_status": "archive", "datestamp": "2023-08-19 20:50:24", "lastmod": "2024-01-13 05:31:19", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "El-Aidi-Bahaa", "name": { "family": "El-Aidi", "given": "Bahaa" } } ] }, "title": "Nonlinear earthquake response of concrete gravity dam systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1989: PB-89-193124/AS\n\nAccepted Version - 8802.pdf
", "abstract": "The earthquake response of concrete gravity dam systems is investigated with emphasis on the nonlinear behavior associated with tensile concrete cracking and water cavitation. A single dam-monolith is considered and is assumed to respond independently as a two-dimensional system under plane stress conditions. The two-dimensional assumption is also extended to model the compressible water body impounded upstream of the dam. Standard displacement-based finite element techniques are used to spatially discretize the field equations and produce a single symmetric matrix equation for the dam-water system. Energy dissipation in the reservoir, through radiation in the infinite upstream direction and absorption at the bottom, is approximately accounted for, and a set of numerical examples is presented to demonstrate the accuracy of the present formulation in modeling the linear earthquake response of infinite reservoirs. An approximate procedure to account for dam-foundation interaction is incorporated based on the response of a rigid plate attached to a three-dimensional viscoelastic halfspace.\n\nWater cavitation is modeled by a smeared approach which uses a bilinear pressure-strain relation. It is shown that the water response becomes dominated by spurious high frequency oscillations upon closure of cavitated regions, and improved results can be obtained by using some stiffness-proportional damping in the water reservoir. As demonstrated in an example analysis of Pine Flat Dam (linear dam), cavitation occurs in the upper part of the reservoir along the dam face, unlike other investigations which show cavitated regions at considerable distances from the dam, and both the tensile pressure cutoffs and compressive impacts have a minor effect on the dam response.\n\nTensile cracks are incorporated using the smeared crack approach, and sliding along closed cracks is allowed. Coupling effects inherent in the finite element formulation are explained, and their influence on open and closed cracks is investigated. Propagation of cracks is monitored in an interactive environment which uses an equivalent strength criterion and allows for user input; remeshing is avoided. The algorithm adopted here produces narrow cracks, unlike many other investigations which show large zones of cracking. An extensive numerical study of Pine Flat Dam demonstrates some interesting features of the nonlinear response of the system, identifies potential failure mechanisms, and reveals a number of difficulties that the analysis encounters. Although no instability of the dam occurs, the numerical difficulties will have to be overcome before definite conclusions regarding stability can be made. It is shown that cracking reduces the hydrodynamic pressures in the reservoir and, hence, reduces water cavitation.", "date": "2002-03-11", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1988.EERL-88-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1988.EERL-88-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8802.pdf", "url": "https://authors.library.caltech.edu/records/vcyn6-yeb92/files/8802.pdf" }, "pub_year": "2002", "author_list": "El-Aidi, Bahaa" }, { "id": "https://authors.library.caltech.edu/records/t41ph-mex06", "eprint_id": 26533, "eprint_status": "archive", "datestamp": "2023-08-19 08:54:57", "lastmod": "2024-01-13 05:31:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Shaikhutdinov-R-V", "name": { "family": "Shaikhutdinov", "given": "R. V." } }, { "id": "Au-Siu-Kui", "name": { "family": "Au", "given": "S. K." } }, { "id": "Mizukoshi-K", "name": { "family": "Mizukoshi", "given": "K." } }, { "id": "Miyamura-M", "name": { "family": "Miyamura", "given": "M." } }, { "id": "Ishida-H", "name": { "family": "Ishida", "given": "H." } }, { "id": "Moroi-T", "name": { "family": "Moroi", "given": "T." } }, { "id": "Tsukada-Y", "name": { "family": "Tsukada", "given": "Y." } }, { "id": "Masuda-M", "name": { "family": "Masuda", "given": "M." } } ] }, "title": "Impact of Seismic Risk on Lifetime Property Values", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - BeckPorterEtAl2002.pdf
", "abstract": "This report presents a methodology for establishing the uncertain net asset value, NAV, of a real-estate investment opportunity considering both market risk and seismic risk for the property. It also presents a decision-making procedure to assist in making real-estate investment choices under conditions of uncertainty and risk-aversion. It is shown that that market risk, as measured by the coefficient of variation of NAV, is at least 0.2 and may exceed 1.0. In a situation of such high uncertainty, where potential gains and losses are large relative to a decision-maker's risk tolerance, it is appropriate to adopt a decision-analysis approach to real-estate investment decision-making. A simple equation for doing so is presented. The decision-analysis approach uses the certainty equivalent, CE, as opposed to NAV as the basis for investment decision-making. That is, when faced with multiple investment alternatives, one should choose the alternative that maximizes CE. It is shown that CE is less than the expected value of NAV by an amount proportional to the variance of NAV and the inverse of the decision-maker's risk tolerance, [rho]. \n\nThe procedure for establishing NAV and CE is illustrated in parallel demonstrations by CUREE and Kajima research teams. The CUREE demonstration is performed using a real 1960s-era hotel building in Van Nuys, California. The building, a 7-story non-ductile reinforced-concrete moment-frame building, is analyzed using the assembly-based vulnerability (ABV) method, developed in Phase III of the CUREE-Kajima Joint Research Program. The building is analyzed three ways: in its condition prior to the 1994 Northridge Earthquake, with a hypothetical shearwall upgrade, and with earthquake insurance. This is the first application of ABV to a real building, and the first time ABV has incorporated stochastic structural analyses that consider uncertainties in the mass, damping, and force-deformation behavior of the structure, along with uncertainties in ground motion, component damageability, and repair costs. New fragility functions are developed for the reinforced concrete flexural members using published laboratory test data, and new unit repair costs for these components are developed by a professional construction cost estimator. Four investment alternatives are considered: do not buy; buy; buy and retrofit; and buy and insure. It is found that the best alternative for most reasonable values of discount rate, risk tolerance, and market risk is to buy and leave the building as-is. However, risk tolerance and market risk (variability of income) both materially affect the decision. That is, for certain ranges of each parameter, the best investment alternative changes. This indicates that expected-value decision-making is inappropriate for some decision-makers and investment opportunities. It is also found that the majority of the economic seismic risk results from shaking of S[subscript a] < 0.3g, i.e., shaking with return periods on the order of 50 to 100 yr that cause primarily architectural damage, rather than from the strong, rare events of which common probable maximum loss (PML) measurements are indicative. \n\nThe Kajima demonstration is performed using three Tokyo buildings. A nine-story, steel-reinforced-concrete building built in 1961 is analyzed as two designs: as-is, and with a steel-braced-frame structural upgrade. The third building is 29-story, 1999 steel-frame structure. The three buildings are intended to meet collapse-prevention, life-safety, and operational performance levels, respectively, in shaking with 10%exceedance probability in 50 years. The buildings are assessed using levels 2 and 3 of Kajima's three-level analysis methodology. These are semi-assembly based approaches, which subdivide a building into categories of components, estimate the loss of these component categories for given ground motions, and combine the losses for the entire building. The two methods are used to estimate annualized losses and to create curves that relate loss to exceedance probability. The results are incorporated in the input to a sophisticated program developed by the Kajima Corporation, called Kajima D, which forecasts cash flows for office, retail, and residential projects for purposes of property screening, due diligence, negotiation, financial structuring, and strategic planning. The result is an estimate of NAV for each building. A parametric study of CE for each building is presented, along with a simplified model for calculating CE as a function of mean NAV and coefficient of variation of NAV. The equation agrees with that developed in parallel by the CUREE team. \n\nBoth the CUREE and Kajima teams collaborated with a number of real-estate investors to understand their seismic risk-management practices, and to formulate and to assess the viability of the proposed decision-making methodologies. Investors were interviewed to elicit their risk-tolerance, r, using scripts developed and presented here in English and Japanese. Results of 10 such interviews are presented, which show that a strong relationship exists between a decision-maker's annual revenue, R, and his or her risk tolerance, [rho is approximately equal to] 0.0075R[superscript 1.34]. The interviews show that earthquake risk is a marginal consideration in current investment practice. Probable maximum loss (PML) is the only earthquake risk parameter these investors consider, and they typically do not use seismic risk at all in their financial analysis of an investment opportunity. For competitive reasons, a public investor interviewed here would not wish to account for seismic risk in his financial analysis unless rating agencies required him to do so or such consideration otherwise became standard practice. However, in cases where seismic risk is high enough to significantly reduce return, a private investor expressed the desire to account for seismic risk via expected annualized loss (EAL) if it were inexpensive to do so, i.e., if the cost of calculating the EAL were not substantially greater than that of PML alone. \n\nThe study results point to a number of interesting opportunities for future research, namely: improve the market-risk stochastic model, including comparison of actual long-term income with initial income projections; improve the risk-attitude interview; account for uncertainties in repair method and in the relationship between repair cost and loss; relate the damage state of structural elements with points on the force-deformation relationship; examine simpler dynamic analysis as a means to estimate vulnerability; examine the relationship between simplified engineering demand parameters and performance; enhance category-based vulnerability functions by compiling a library of building-specific ones; and work with lenders and real-estate industry analysts to determine the conditions under which seismic risk should be reflected in investors' financial analyses.", "date": "2002-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2002.EERL-2002-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:2002.EERL-2002-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "BeckPorterEtAl2002.pdf", "url": "https://authors.library.caltech.edu/records/t41ph-mex06/files/BeckPorterEtAl2002.pdf" }, "pub_year": "2002", "author_list": "Beck, James L.; Porter, Keith A.; et el." }, { "id": "https://authors.library.caltech.edu/records/ztgde-n9a10", "eprint_id": 26539, "eprint_status": "archive", "datestamp": "2023-08-19 08:55:23", "lastmod": "2024-01-13 05:31:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huixian-Liu", "name": { "family": "Huixian", "given": "Liu" } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } }, { "id": "Lili-Xie", "name": { "family": "Lili", "given": "Xie" } }, { "id": "Duxin-He", "name": { "family": "Duxin", "given": "He" } } ] }, "title": "The Great Tangshan Earthquake of 1976", "ispublished": "unpub", "full_text_status": "public", "abstract": "At 4:00 a.m. on July 28, 1976 the city of Tangshan, China ceased to exist. A magnitude 7.8 earthquake was generated by a fault that passed through the city and caused 85% of the buildings to collapse or to be so seriously damaged as to be unusable, and the death toll was enormous. The earthquake caused the failures of the electric power system, the water supply system, the sewer system, the telephone and telegraph systems, and radio communications; and the large coal mines and the industries dependent on coal were devastated. The railway and highway bridges collapsed so that the city was isolated from the external world. Before the earthquake Tangshan had 1,000,000 inhabitants and it has been estimated that about one half were killed. Although the building code had seismic design requirements, Tangshan was in a zone requiring no earthquake design.\n\nAn earthquake disaster requires a large earthquake efficiently close to a large city to produce destructive ground shaking and that the city has buildings not designed to resist earthquakes. The Tangshan disaster met all these requirements and the result was the greatest earthquake disaster in the history of the world. Many countries have cities whose situation is similar to that of pre-earthquake Tangshan, that is, an estimated low probability of being struck by destructive ground shaking and many buildings with low seismic resistance so this report should be of special interest to engineers, architects, and government officials in these seismic countries. The report shows what can happen when an unexpected earthquake strikes an unprepared city and it makes clear the need for earthquake preparedness even if the probability of an earthquake is assumed to be low.", "date": "2002-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL.2002.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL.2002.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "doi": "10.7907/AFEE-X539", "primary_object": { "basename": "TangshanEQRept.htm", "url": "https://authors.library.caltech.edu/records/ztgde-n9a10/files/TangshanEQRept.htm" }, "pub_year": "2002", "author_list": "Huixian, Liu; Housner, George W.; et el." }, { "id": "https://authors.library.caltech.edu/records/x40f3-qy735", "eprint_id": 26528, "eprint_status": "archive", "datestamp": "2023-08-19 08:54:33", "lastmod": "2023-10-24 16:22:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Seligson-H-A", "name": { "family": "Seligson", "given": "Hope A." } }, { "id": "Scawthorn-C-R", "name": { "family": "Scawthorn", "given": "Charles R." } }, { "id": "Tobin-L-T", "name": { "family": "Tobin", "given": "L. Thomas" } }, { "id": "Young-R", "name": { "family": "Young", "given": "Ray" } }, { "id": "Boyd-T", "name": { "family": "Boyd", "given": "Tom" } } ] }, "title": "Improving Loss Estimation for Woodframe Buildings. Volume 1: Report", "ispublished": "unpub", "full_text_status": "public", "note": "Final Report of Tasks 4.1 and 4.5 of the CUREE-Caltech Woodframe Project", "abstract": "This report documents Tasks 4.1 and 4.5 of the CUREE-Caltech Woodframe Project. It presents a theoretical and empirical methodology for creating probabilistic relationships between seismic shaking severity and physical damage and loss for buildings in general, and for woodframe buildings in particular. The methodology, called assembly-based vulnerability (ABV), is illustrated for 19 specific woodframe buildings of varying ages, sizes, configuration, quality of construction, and retrofit and redesign conditions. The study employs variations on four basic floorplans, called index buildings. These include a small house and a large house, a townhouse and an apartment building. The resulting seismic vulnerability functions give the probability distribution of repair cost as a function of instrumental ground-motion severity. These vulnerability functions are useful by themselves, and are also transformed to seismic fragility functions compatible with the HAZUS software. \n\nThe methods and data employed here use well-accepted structural engineering techniques, laboratory test data and computer programs produced by Element 1 of the CUREE-Caltech Woodframe Project, other recently published research, and standard construction cost-estimating methods. While based on such well established principles, this report represents a substantially new contribution to the field of earthquake loss estimation. Its methodology is notable in that it calculates detailed structural response using nonlinear time-history structural analysis as opposed to the simplifying assumptions required by nonlinear pushover methods. It models physical damage at the level of individual building assemblies such as individual windows, segments of wall, etc., for which detailed laboratory testing is available, as opposed to two or three broad component categories that cannot be directly tested. And it explicitly models uncertainty in ground motion, structural response, component damageability, and contractor costs. Consequently, a very detailed, verifiable, probabilistic picture of physical performance and repair cost is produced, capable of informing a variety of decisions regarding seismic retrofit, code development, code enforcement, performance-based design for above-code applications, and insurance practices.", "date": "2002-01-01", "date_type": "published", "publisher": "Consortium of Universities for Research in Earthquake Engineering, Richmond, CA", "id_number": "CaltechEERL:2002.EERL-2002-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:2002.EERL-2002-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Chapter_1_Introduction_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_1_Introduction_ver_3.doc" }, "related_objects": [ { "basename": "Chapter_4_Analysis_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_4_Analysis_ver_3.doc" }, { "basename": "Chapter_5_Results_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_5_Results_ver_3.doc" }, { "basename": "Chapter_6_Risk_Illustration_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_6_Risk_Illustration_ver_3.doc" }, { "basename": "Chapter_8_References_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_8_References_ver_3.doc" }, { "basename": "Improving_Loss_Estimation_for_Woodframe_Buildings_vol_1.pdf", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Improving_Loss_Estimation_for_Woodframe_Buildings_vol_1.pdf" }, { "basename": "Chapter_2_Review_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_2_Review_ver_3.doc" }, { "basename": "Chapter_3_Methodology_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_3_Methodology_ver_3.doc" }, { "basename": "Chapter_7_Conclusions_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_7_Conclusions_ver_3.doc" }, { "basename": "Chapter_9_Glossary_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Chapter_9_Glossary_ver_3.doc" }, { "basename": "Cover_Summary_and_TOC_ver_3.doc", "url": "https://authors.library.caltech.edu/records/x40f3-qy735/files/Cover_Summary_and_TOC_ver_3.doc" } ], "pub_year": "2002", "author_list": "Porter, Keith A.; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/rxh8v-kjg13", "eprint_id": 26534, "eprint_status": "archive", "datestamp": "2023-08-19 08:55:02", "lastmod": "2023-10-24 16:22:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yuen-Ka-Veng", "name": { "family": "Yuen", "given": "Ka-Veng" }, "orcid": "0000-0002-1755-6668" } ] }, "title": "Model Selection Identification and Robust Control for Dynamical Systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 2002", "abstract": "To fully exploit new technologies for response mitigation and structural health monitoring, improved system identification and controller design methodologies are desirable that explicitly treat all the inherent uncertainties. In this thesis, a probabilistic framework is presented for model selection, identification and robust control of smart structural systems under dynamical loads, such as those induced by wind or earthquakes. First, a probabilistic based approach is introduced for selecting the most plausible class of models for a dynamical system using its response measurements. The proposed approach allows for quantitatively comparing the plausibility of different classes of models among a specified set of classes. \n\nThen, two probabilistic identification techniques are presented. The first one is for modal identification using nonstationary response measurements and the second one is for updating nonlinear models using incomplete noisy measurements only. These methods allow for updating of the uncertainties associated with the values of the parameters controlling the dynamic behavior of the structure by using noisy response measurements only. The probabilistic framework is very well-suited for solving this nonunique problem and the updated probabilistic description of the system can be used to design a robust controller of the system. It can also be used for structural health monitoring. \n\nFinally, a reliability-based stochastic robust control approach is used to design the controller for an active control system. Feedback of the incomplete response at earlier time steps is used, without any state estimation. The optimal controller is chosen by minimizing the robust failure probability over a set of possible models for the system. Here, failure means excessive levels of one or more response quantities representative of the performance of the structure and the control devices. When calculating the robust failure probability, the plausibility of each model as a representation of the system's dynamic behavior is quantified by a probability distribution over the set of possible models; this distribution is initially based on engineering judgement, but it can be updated using the aforementioned system identification approaches if dynamic data become available from the structure. Examples are presented to illustrate the proposed controller design procedure, which includes the procedure of model selection, identification and robust control for smart structures.", "date": "2002-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2002.EERL-2002-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:2002.EERL-2002-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL200203.pdf", "url": "https://authors.library.caltech.edu/records/rxh8v-kjg13/files/EERL200203.pdf" }, "pub_year": "2002", "author_list": "Yuen, Ka-Veng" }, { "id": "https://authors.library.caltech.edu/records/sby1n-jag19", "eprint_id": 26529, "eprint_status": "archive", "datestamp": "2023-08-19 08:54:52", "lastmod": "2023-10-24 16:22:39", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Porter-K-A", "name": { "family": "Porter", "given": "Keith A." } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Seligson-H-A", "name": { "family": "Seligson", "given": "Hope A." } }, { "id": "Scawthorn-C-R", "name": { "family": "Scawthorn", "given": "Charles R." } }, { "id": "Tobin-L-T", "name": { "family": "Tobin", "given": "L. Thomas" } }, { "id": "Young-R", "name": { "family": "Young", "given": "Ray" } }, { "id": "Boyd-T", "name": { "family": "Boyd", "given": "Tom" } } ] }, "title": "Improving Loss Estimation for Woodframe Buildings. Volume 2: Appendices", "ispublished": "unpub", "full_text_status": "public", "note": "Final Report on Tasks 4.1 and 4.5 of the CUREE-Caltech Woodframe Project", "abstract": "This report documents Tasks 4.1 and 4.5 of the CUREE-Caltech Woodframe Project. It presents a theoretical and empirical methodology for creating probabilistic relationships between seismic shaking severity and physical damage and loss for buildings in general, and for woodframe buildings in particular. The methodology, called assembly-based vulnerability (ABV), is illustrated for 19 specific woodframe buildings of varying ages, sizes, configuration, quality of construction, and retrofit and redesign conditions. The study employs variations on four basic floorplans, called index buildings. These include a small house and a large house, a townhouse and an apartment building. The resulting seismic vulnerability functions give the probability distribution of repair cost as a function of instrumental ground-motion severity. These vulnerability functions are useful by themselves, and are also transformed to seismic fragility functions compatible with the HAZUS software. \n\nThe methods and data employed here use well-accepted structural engineering techniques, laboratory test data and computer programs produced by Element 1 of the CUREE-Caltech Woodframe Project, other recently published research, and standard construction cost-estimating methods. While based on such well established principles, this report represents a substantially new contribution to the field of earthquake loss estimation. Its methodology is notable in that it calculates detailed structural response using nonlinear time-history structural analysis as opposed to the simplifying assumptions required by nonlinear pushover methods. It models physical damage at the level of individual building assemblies such as individual windows, segments of wall, etc., for which detailed laboratory testing is available, as opposed to two or three broad component categories that cannot be directly tested. And it explicitly models uncertainty in ground motion, structural response, component damageability, and contractor costs. Consequently, a very detailed, verifiable, probabilistic picture of physical performance and repair cost is produced, capable of informing a variety of decisions regarding seismic retrofit, code development, code enforcement, performance-based design for above-code applications, and insurance practices.", "date": "2002-01-01", "date_type": "published", "publisher": "Consortium of Universities for Research in Earthquake Engineering, Richmond, CA", "id_number": "CaltechEERL:2002.EERL-2002-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:2002.EERL-2002-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Appendix_A_Literature_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_A_Literature_ver_3.doc" }, "related_objects": [ { "basename": "Appendix_B_Index_Buildings_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_B_Index_Buildings_ver_3.doc" }, { "basename": "Appendix_F_Construction_Costs_part_2_cost_sheets_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_F_Construction_Costs_part_2_cost_sheets_ver_3.doc" }, { "basename": "Appendix_G_Vulnerability_Tables_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_G_Vulnerability_Tables_ver_3.doc" }, { "basename": "Cover_for_volume_2_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Cover_for_volume_2_ver_3.doc" }, { "basename": "Improving_Loss_Estimation_for_Woodframe_Buildings_vol_2.pdf", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Improving_Loss_Estimation_for_Woodframe_Buildings_vol_2.pdf" }, { "basename": "Appendix_C_Structural_Modeling_ver_4_cover.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_C_Structural_Modeling_ver_4_cover.doc" }, { "basename": "Appendix_D_ABV_Methodology_cover_and_back_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_D_ABV_Methodology_cover_and_back_ver_3.doc" }, { "basename": "Appendix_E_Assembly_Fragilities_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_E_Assembly_Fragilities_ver_3.doc" }, { "basename": "Appendix_F_Construction_Costs_part_1_text_ver_3.doc", "url": "https://authors.library.caltech.edu/records/sby1n-jag19/files/Appendix_F_Construction_Costs_part_1_text_ver_3.doc" } ], "pub_year": "2002", "author_list": "Porter, Keith A.; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/s0px6-cg190", "eprint_id": 26432, "eprint_status": "archive", "datestamp": "2023-08-19 12:42:34", "lastmod": "2024-01-13 05:31:13", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "McVerry-Graeme-Haynes", "name": { "family": "McVerry", "given": "Graeme Haynes" } } ] }, "title": "Frequency domain identification of structural models from earthquake records", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1980: PB-80-194301\n\nAccepted Version - 7902.pdf
", "abstract": "The usefulness of simple linear mathematical models for representing the behaviour of tall buildings during earthquake response is investigated for a variety of structures over a range of motions including the onset of structural damage. The linear models which best reproduce the measured response of the structures are determined from the recorded earthquake motions. In order to improve upon unsatisfactory results obtained by methods using transfer functions, a systematic frequency domain identification technique is developed to determine the optimal models. The periods, dampings and participation factors are estimated for the structural modes which are dominant in the measured response.\n\nThe identification is performed by finding the values of the modal parameters which produce a least-squares match over a specified frequency range between the unsmoothed, complex-valued, finite Fourier transform of the acceleration response recorded in the structure and that calculated for the model. It is possible to identify a single linear model appropriate for the entire response, or to approximate the nonlinear behavior exhibited by some structures with a series of models optimal for different segments of the response.\n\nThe investigation considered the earthquake records obtained in ten structures ranging in height from seven to forty-two stories. Most of the records were from the San Fernando earthquake. For two of these structures, smaller-amplitude records from more distant earthquakes were also analyzed. The maximum response amplitudes ranged from approximately 0.025 g to 0.40g.\n\nThe very small amplitude responses were reproduced well by linear models with fundamental periods similar to those measured in vibration tests. Most of the San Fernando responses in which no structural damage occurred (typically 0.2g-0.3g maximum accelerations) were also matched closely by linear models. However, the effective fundamental periods in these responses were characteristically 50 percent longer than in vibration tests. The average first mode damping identified from these records was about 5 percent of critical. Only those motions which produced structural damage could not be represented satisfactorily by time-invariant linear models. Segment-by-segment analysis of these records revealed effective periods of two to three times the vibration test values with fundamental mode dampings of 15 to 20 percent.\n\nThe systematic identification technique generally achieves better matches of the recorded responses than those produced by models derived by trial-and-error methods, and consequently more reliable estimates of the modal parameters. The close reproductions of the measured motions confirm the accuracy of linear models with only a few modes for representing the behaviour during earthquake response of tall buildings in which no structural damage occurs.", "date": "2001-12-04", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1979.EERL-79-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1979.EERL-79-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7902.pdf", "url": "https://authors.library.caltech.edu/records/s0px6-cg190/files/7902.pdf" }, "pub_year": "2001", "author_list": "McVerry, Graeme Haynes" }, { "id": "https://authors.library.caltech.edu/records/acv46-4h769", "eprint_id": 26428, "eprint_status": "archive", "datestamp": "2023-08-19 10:11:42", "lastmod": "2024-01-13 05:31:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Foutch-Douglas-Allen", "name": { "family": "Foutch", "given": "Douglas Allen" } } ] }, "title": "A study of the vibrational characteristics of two multistory buildings", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1977\n\nAccepted Version - 7603.pdf
", "abstract": "Forced vibration tests and associated analysis of two multistory buildings are described. In one case, the dynamic properties of the building measured during the tests are compared to those predicted by simple analytical models. A three-dimensional finite element model of the second building was constructed for the purpose of evaluating the accuracy of this type of analysis for predicting the observed dynamic properties of the structure.\n\nForced vibration tests were performed on Millikan Library, a nine-story reinforced concrete shear wall building. Measurements of three-dimensional motions of approximately 50 points on each of six floors (including the basement) were taken for excitation in the N-S and E-W directions. The results revealed a complex interaction between lateral and vertical load carrying systems in both directions The results also suggest that a significant change in the foundation response of the structure occurred in the stiffer N-S direction during the San Fernando earthquake. This phenomenon was investigated through the use of two analytical models of the building which included the effects of soil-structure interaction.\n\nThe Ralph M. Parsons World Headquarters building, a twelvestory steel frame structure, was also tested. The natural frequencies, three-dimensional mode shapes, and damping coefficients of nine modes of vibration were determined. Other features of this investigation included the study of nonlinearities associated with increasing levels of response and the measurement of strain in one of the columns of the structure during forced excitation. The dynamic characteristics of the building determined by these tests are compared to those predicted by a finite element model of the structure. The properties of primarily translational modes are predicted reasonably well; but adequate predictions of torsional motions were not obtained. The comparison between measured and predicted strains suggests that estimates of stress obtained from finite element analyses of buildings should be within 25 percent of those experienced by the structure for a known excitation.", "date": "2001-12-04", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1976.EERL-76-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1976.EERL-76-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7603.pdf", "url": "https://authors.library.caltech.edu/records/acv46-4h769/files/7603.pdf" }, "pub_year": "2001", "author_list": "Foutch, Douglas Allen" }, { "id": "https://authors.library.caltech.edu/records/kq2nw-70j55", "eprint_id": 26425, "eprint_status": "archive", "datestamp": "2023-08-19 09:34:43", "lastmod": "2024-01-13 05:31:08", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miller-Richard-Keith", "name": { "family": "Miller", "given": "Richard Keith" } } ] }, "title": "The Steady-state response of multidegree-of-freedom systems with a spatially localized nonlinearity", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1976: PB 252 459/AS\n\nAccepted Version - 7503.pdf
", "abstract": "This thesis is concerned with the dynamic response of a general multidegree-of-freedom linear system with a one dimensional nonlinear constraint attached between two points. The nonlinear constraint is assumed to consist of rate-independent conservative and hysteretic nonlinearities and may contain a viscous dissipation element. The dynamic equations for general spatial and temporal load distributions are derived for both continuous and discrete systems. The method of equivalent linearization is used to develop equations which govern the approximate steady-state response to generally distributed loads with harmonic time dependence.\n\nThe qualitative response behavior of a class of undamped chainlike structures with a nonlinear terminal constraint is investigated. it is shown that the hardening or softening behavior of every resonance curve is similar and is determined by the properties of the constraint. Also examined are the number and location of resonance curves, the boundedness of the forced response, the loci of response extrema, and other characteristics of the response. Particular consideration is given to the dependence of the response characteristics on the properties of the linear system, the nonlinear constraint, and the load distribution.\n\nNumerical examples of the approximate steady-state response of three structural systems are presented. These examples illustrate the application of the formulation and qualitative theory.\n\nIt is shown that disconnected response curves and response curves which cross are obtained for base excitation of a uniform shear beam with a cubic spring foundation. Disconnected response curves are also obtained for the steady-state response to a concentrated load of a chainlike structure with a hardening hysteretic constraint. The accuracy of the approximate response curves is investigated.", "date": "2001-11-28", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7503.pdf", "url": "https://authors.library.caltech.edu/records/kq2nw-70j55/files/7503.pdf" }, "pub_year": "2001", "author_list": "Miller, Richard Keith" }, { "id": "https://authors.library.caltech.edu/records/f9nx8-jdj79", "eprint_id": 26415, "eprint_status": "archive", "datestamp": "2023-08-19 08:22:27", "lastmod": "2024-01-13 05:31:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crouse-C-B", "name": { "family": "Crouse", "given": "C. B." } } ] }, "title": "Engineering studies of the San Fernando earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1974\n\nAccepted Version - 7304.pdf
", "abstract": "A number of accelerograms obtained during the San Fernando earthquake were analyzed to investigate the nature of the strong motion. The particular features studied were soil-structure interaction and the relative influence of local site conditions versus the source mechanism and travel paths of earthquake waves.\n\nEvidence of soil-structure interaction in the EW fundamental mode of the Hollywood Storage building is seen in the earthquake data. General agreement exists up to - 5 c.p.s. in both lateral directions between theoretical, base to free field transfer functions and transfer functions derived from accelerograms obtained in the basement and adjacent parking lot. There was no evidence of soil-structure interaction in the Millikan Library and Athenaeum buildings on the Caltech campus, and this effect could not account for the major differences in their accelerograms.\n\nAccelerogram, Fourier Amplitude Spectra, and Response Spectra data were compared from a group of six tall buildings close together near Wilshire Blvd. and Normandie Ave. in Los Angeles and from seven surrounding buildings, two to three miles away. The data indicated that local site conditions and soll-structure interaction were not major contributors to the observed differences in the response at these sites. There was correlation between the degree of similarity in the response at two sites and their distance apart. A simple wave superposition model with numerical examples confirms this correlation.", "date": "2001-11-19", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7304.pdf", "url": "https://authors.library.caltech.edu/records/f9nx8-jdj79/files/7304.pdf" }, "pub_year": "2001", "author_list": "Crouse, C. B." }, { "id": "https://authors.library.caltech.edu/records/wqyjg-q8694", "eprint_id": 26409, "eprint_status": "archive", "datestamp": "2023-08-19 07:30:01", "lastmod": "2023-10-24 16:18:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Skattum-Knut-Sverre", "name": { "family": "Skattum", "given": "Knut Sverre" } } ] }, "title": "Dynamic Analysis of Coupled Shear Walls and Sandwich Beams", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1971: PB 205 267\n\nPublished - 7106.pdf
", "abstract": "A study is made of the free vibration of planar coupled shear walls, a common lateral load-resisting configuration in building construction where two walls are coupled together by a system of discrete spandrel beams. The differential equations and boundary conditions are obtained by the variational method, and by assuming that the spandrels can be replaced by a continuous system of laminae, or small beams.\n\nNatural frequencies and mode shapes are determined, and the results are presented in a number of figures from which the natural frequencies of any coupled shear wall can be extracted. The importance of including vertical displacement in the analysis is discussed, and a study of the effect of neglecting the vertical inertia term is given. These cases are illustrated with graphs and with one specific example. Investigations are also made of the asymptotic behavior of the system as the spandrels become weak, as they become stiff, and as the frequencies become large.\n\nFinally, the theory of sandwich beams is presented and compared to that for coupled shear walls. It is observed that for most cases of constant properties, the differential equations (and boundary conditions) reduce to the same mathematical form for both theories.", "date": "2001-11-16", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7106.pdf", "url": "https://authors.library.caltech.edu/records/wqyjg-q8694/files/7106.pdf" }, "pub_year": "2001", "author_list": "Skattum, Knut Sverre" }, { "id": "https://authors.library.caltech.edu/records/ffqva-8vw81", "eprint_id": 26410, "eprint_status": "archive", "datestamp": "2023-08-19 07:30:06", "lastmod": "2024-01-13 05:30:58", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hoerner-John-Brent", "name": { "family": "Hoerner", "given": "John Brent" } } ] }, "title": "Modal coupling and earthquake response of tall buildings", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1971: PB 207 635\n\nAccepted Version - 7107.pdf
", "abstract": "The major dynamic features of tall buildings are within the scope of a shear beam model. Herein the usual one-dimensional model is extended to three dimensions to include modes with translational and rotational components. The analysis is restricted to the continuous model with linear response.\n\nA class of models for tall buildings is presented which possesses three sets of mutually orthogonal coupled modes. The amount of modal coupling is related to the eccentricities divided by the translational-torsional frequency differences. Strong modal coupling can occur if the eccentricities and frequency differences are small, as in a rectangular building with a smooth distribution of columns. A perturbation scheme is developed for buildings almost in this class. The perturbation method is applicable to buildings with nearly vertical mass and rigidity centers and with ith-modes of nearly the same shape.\n\nRotational components of earthquake response in buildings primarily results from modal coupling, and it is shown that modal coupling can increase response on the building's perimeter. Furthermore, rectangular buildings with modal coupling can show a beating-type frequency response, for which the more usual r.m.s. combination should be replaced by an absolute sum. These effects can significantly increase certain response parameters. The corners of a rectangular building can have a 95% increase in shear, as compared with 30% implied by a 5% eccentricity in the codes. Base shears and overturning moments can be increased by 40%.", "date": "2001-11-16", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7107.pdf", "url": "https://authors.library.caltech.edu/records/ffqva-8vw81/files/7107.pdf" }, "pub_year": "2001", "author_list": "Hoerner, John Brent" }, { "id": "https://authors.library.caltech.edu/records/xdqf3-f0569", "eprint_id": 26403, "eprint_status": "archive", "datestamp": "2023-08-19 01:29:38", "lastmod": "2024-01-13 05:30:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chan-Eduardo", "name": { "family": "Chan", "given": "Eduardo" } } ] }, "title": "Optimal design of building structures using genetic algorithms", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1997\n\nAccepted Version - 9706.pdf
", "abstract": "A general framework for multi-criteria optimal design is presented which is well-suited for automated design of structural systems. A systematic computer-aided optimal design decision process is developed which allows the designer to rapidly evaluate and improve a proposed design by taking into account the major factors of interest related to different aspects such as design, construction, and operation.\n\nThe proposed optimal design process requires the selection of the most promising choice of design parameters taken from a large design space, based on an evaluation using specified criteria. The design parameters specify a particular design, and so they relate to member sizes, structural configuration, etc. The evaluation of the design uses performance parameters which may include structural response parameters, risks due to uncertain loads and modeling errors, construction and operating costs, etc. Preference functions are used to implement the design criteria in a \"soft\" form. These preference functions give a measure of the degree of satisfaction of each design criterion. The overall evaluation measure for a design is built up from the individual measures for each criterion through a preference combination rule. The goal of the optimal design process is to obtain a design that has the highest overall evaluation measure - an optimization problem.\n\nGenetic algorithms are stochastic optimization methods that are based on evolutionary theory. They provide the exploration power necessary to explore high-dimensional search spaces to seek these optimal solutions. Two special genetic algorithms, hGA and vGA, are presented here for continuous and discrete optimization problems, respectively.\n\nThe methodology is demonstrated with several examples involving the design of truss and frame systems. These examples are solved by using the proposed hGA and vGA.", "date": "2001-11-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "9706.pdf", "url": "https://authors.library.caltech.edu/records/xdqf3-f0569/files/9706.pdf" }, "pub_year": "2001", "author_list": "Chan, Eduardo" }, { "id": "https://authors.library.caltech.edu/records/a4s5c-pak39", "eprint_id": 26399, "eprint_status": "archive", "datestamp": "2023-08-20 05:46:29", "lastmod": "2024-01-13 05:30:48", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Liping", "name": { "family": "Huang", "given": "Liping" } } ] }, "title": "Mode-like properties and identification of nonlinear vibrating systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1995\n\nAccepted Version - 9504.pdf
", "abstract": "A study is made of mode-like properties and identification of nonlinear systems and their applications in structural seismic analysis.\n\nIn the thesis, mode-like behavior of nonlinear systems is examined. The modal frequencies and mode shapes of nonlinear systems are found to be dependent on the response. Based on approximation, amplitude-dependent mode shape is defined and approximate methods for calculation of modal frequencies and mode shapes (instantaneous and amplitude-dependent) are presented. Based on amplitude-dependent modal relationship, amplitude-dependent models of modal equations which are valid in large range of response and suitable for unique identification are proposed and the corresponding modal identification procedures are developed. The applicability of the new models and identification algorithms is tested through the analysis of an ideal 3DOF nonlinear system.\n\nAs applications, the seismic responses of a 47-story building and a 4-story building are investigated using the presented methods. The modal parameters and modal equations of the structures are identified.", "date": "2001-11-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9504.pdf", "url": "https://authors.library.caltech.edu/records/a4s5c-pak39/files/9504.pdf" }, "pub_year": "2001", "author_list": "Huang, Liping" }, { "id": "https://authors.library.caltech.edu/records/m3eqr-95r96", "eprint_id": 26397, "eprint_status": "archive", "datestamp": "2023-08-20 05:52:32", "lastmod": "2024-01-13 05:30:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Xiaodong", "name": { "family": "Chen", "given": "Xiaodong" } } ] }, "title": "Near-field ground motion from the Landers earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "Civil Engineer, 1995\n\nAccepted Version - 9502.pdf
", "abstract": "In order to investigate near-field ground motions, an important Lucerne Valley record from the Landers earthquake was studied. The Lucerne Valley record was recorded on the Kinemetrics SMA-2/EMA instrument located 2 km from the fault. Since the characteristics of the SMA-2/EMA instrument were not completely understood and the conventional data processing procedures have difficulty in recovering long-period information from near-field earthquake accelerograms, an instrument test on the SMA-2/EMA was conducted and a new data processing procedure was developed to perform the instrument and baseline corrections.\n\nFor an electro-magnetic transducer, an additional parameter of corner frequency, other than natural frequency, electronic damping ratio and sensitivity, should be considered during instrument correction of the SMA-2/EMA recorded accelerograms. For this purpose, a special instrument correction filter was derived in support of instrument correction and a laboratory test of the SMA-2/EMA accelerograph was conducted for obtaining the characteristic parameters of the instrument. The possible error sources in data recording and playback procedure were also examined and an appropriate baseline correction scheme was formulated for effectively removing the nonphysical trend involved in the earthquake data.\n\nThe new data processing procedure was verified by a set of SMA-2/EMA simulated long-period accelerograms and then applied to the Lucerne Valley record. The results of new data processing revealed the important features of near-field ground motion, which were a displacement offset parallel to the fault and a large pulse-like motion perpendicular to the fault. The response spectra and Fourier spectra were also calculated and compared to those of the conventionally processed record. With these investigations, a number of important conclusions are obtained and several suggestions for future studies are given.", "date": "2001-11-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9502.pdf", "url": "https://authors.library.caltech.edu/records/m3eqr-95r96/files/9502.pdf" }, "pub_year": "2001", "author_list": "Chen, Xiaodong" }, { "id": "https://authors.library.caltech.edu/records/jb8rs-9w788", "eprint_id": 26398, "eprint_status": "archive", "datestamp": "2023-08-20 06:12:11", "lastmod": "2024-01-13 05:30:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hayen-Jeffrey-Clyde", "name": { "family": "Hayen", "given": "Jeffrey Clyde" } } ] }, "title": "Response control of structural systems using semi-actively controlled interactions", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1996\n\nAccepted Version - 9503.pdf
", "abstract": "The objective of the research described herein is to demonstrate conditions under which controlled interactions between two structures or structural components can be made effective in reducing the response of structures that are subjected to seismic excitation. It is shown that the effectiveness depends upon such factors as the control strategy implementation, the interaction element mechanical properties, and the parameters which characterize the dynamic behavior of the structural systems.\n\nA study is conducted to examine the performance of a structural response control approach referred to as Active Interface Damping (AID). This control approach utilizes controlled interactions between two distinct structural systems - or different components of a single structural system - to reduce the resonance buildup that develops during an external excitation. Control devices or elements may be employed to physically produce the interactions between the systems. The proposed control approach differs from some other control approaches in that the sensors, processors, and switching components all operate actively, whereas the interaction elements function passively. The major advantage of this semi-active control technology is that relatively large control forces can be generated with minimal power requirements, which is of prime importance for the control of relatively massive systems, such as structures.\n\nIn the most simple form, the strategy of the control approach is to remove energy associated with vibration from only one system (the primary system). This process is accomplished through the transfer of energy to another system (the auxiliary system) by means of interaction elements, the dissipation of energy directly in the interaction elements, or a combination of both these methods. In a more complex form, the control strategy may be to minimize some composite response measure of the combined primaryauxiliary system. Only the most simple form of the control strategy is considered in the present study.\n\nSeveral physical interpretations of the control approach are possible: one is that the systems represent two adjacent multi-story buildings; another is that the primary system represents a single multi-story building, while the auxiliary system could represent either an externally-situated resilient frame or a relatively small, unrestrained mass - or even be completely absent (in this latter scenario, the interaction elements are internally mounted control devices). The interactions consist of reaction forces that are developed within and transmitted through the elements which are located between the two systems (or different points of a single system). The mechanical properties of these elements can be altered in real time by control signals, so the reaction forces applied to the systems may be changed, and the response control objective is achieved by actively changing the interactions at the interface of the two systems (or different points of a single system).\n\nInitially, a preliminary study of the proposed control approach is conducted within the specialized setting of linear single-degree-of-freedom (SDOF) primary and auxiliary systems. Numerical simulations are performed for a series of control cases using horizontal ground accelerations from an ensemble of earthquake time histories as excitation input. Subsequently, a follow-on study of the proposed control approach is conducted for linear multiple-degree-of-freedom (MDOF) primary and auxiliary systems intended to represent actual structural systems. Based upon the investigation and insight obtained from the preliminary study, a limited number of control cases are considered which include those deemed most effective and implementable. Numerical simulations are again performed using the same excitation input as for the SDOF systems. The control approach is targeted at reducing the response contribution from the fundamental or dominant mode of vibration associated with the primary system. Uniformly-discretized models of a 6-story primary structural system capable of only lateral deformations are considered in most cases. A few cases involving models of a 3-story primary structural system are also examined.", "date": "2001-11-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9503.pdf", "url": "https://authors.library.caltech.edu/records/jb8rs-9w788/files/9503.pdf" }, "pub_year": "2001", "author_list": "Hayen, Jeffrey Clyde" }, { "id": "https://authors.library.caltech.edu/records/wp00m-cmn71", "eprint_id": 26385, "eprint_status": "archive", "datestamp": "2023-08-19 20:19:36", "lastmod": "2024-01-13 05:30:29", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nowak-Paul-Scott", "name": { "family": "Nowak", "given": "Paul Scott" } } ] }, "title": "Effect of nonuniform seismic input on arch dams", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1989: PB 89-194450/AS\n\nAccepted Version - 8803.pdf
", "abstract": "Standard earthquake analyses of civil engineering structures use uniform ground motions even though considerable variations in both amplitude and phase can occur along the foundation interface for long-span bridges and large dams. The objective of this thesis is to quantify the effect that these nonuniformities have on the structural response.\n\nThe nonuniform, free-field motions of the foundation interface are assumed to be caused by incident plane body waves. The medium in which these waves travel is a linear, elastic half-space containing a canyon of uniform cross section in which the structure is placed. The solutions for the free-field motions that are due to incident SH, P and SV waves are calculated using the boundary element method.\n\nAn analysis of Pacoima (arch) dam located near Los Angeles, California, is performed for both uniform and nonuniform excitations. The important effect of nonuniformities in the free-field motions, sometimes leading to a decrease in the dam response and sometimes to an increase, is quantified.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1988.EERL-88-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1988.EERL-88-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8803.pdf", "url": "https://authors.library.caltech.edu/records/wp00m-cmn71/files/8803.pdf" }, "pub_year": "2001", "author_list": "Nowak, Paul Scott" }, { "id": "https://authors.library.caltech.edu/records/vqpgh-vmr92", "eprint_id": 26386, "eprint_status": "archive", "datestamp": "2023-08-19 21:21:20", "lastmod": "2024-01-13 05:30:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Donlon-W-P", "name": { "family": "Donlon", "given": "William P" } } ] }, "title": "Experimental investigation of the nonlinear seismic response of concrete gravity dams", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1989: PB-91-170118\n\nAccepted Version - 8901.pdf
", "abstract": "The nonlinear seismic response of concrete gravity dams is investigated experimentally through the use of small-scale models. Of primary interest is crack formation, crack opening and closing, and sliding along crack planes. Also of concern is the stability of the structure after cracking. Three small-scale models (length scale = 115) of a single monolith of Pine Flat Dam are tested to determine the extent of such behavior and its effect on structural stability. The models are constructed of one polymer-based and two plaster-based materials developed for these experiments. The plaster-based materials fulfill the strength, stiffness, and density requirements established by the laws of similitude, while the polymer-based material fulfills only the stiffness and density requirements and is used only in the lower part of the dam where cracking is not expected. The excitation is a modified version of the N00E component of the 1940 Imperial Valley earthquake, applied to each model's base in the stream direction through a vibration table with high-frequency capability. Tests are performed with and without water in the reservoir. The response of each earthquake test is presented in the form of acceleration and displacement time histories, Fourier spectra, and frames taken from high-speed films of the model's response. The -results of the experiments indicate that the neck region of a concrete gravity dam is most susceptible to cracking, although crack profiles can differ as a result of variations in excitation, material properties, and construction techniques. These results also indicate alternate design techniques which could improve the seismic stability of a cracked gravity dam.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1989.EERL-89-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1989.EERL-89-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8901.pdf", "url": "https://authors.library.caltech.edu/records/vqpgh-vmr92/files/8901.pdf" }, "pub_year": "2001", "author_list": "Donlon, William P" }, { "id": "https://authors.library.caltech.edu/records/8n9eb-yxy63", "eprint_id": 26387, "eprint_status": "archive", "datestamp": "2023-08-19 21:54:21", "lastmod": "2024-01-13 05:30:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jensen-Hector-A", "name": { "family": "Jensen", "given": "Hector A." } } ] }, "title": "Dynamic response of structures with uncertain parameters", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1990: PB-91-154195\n\nAccepted Version - 8902.pdf
", "abstract": "This thesis presents a technique for obtaining the response of linear structural systems with parameter uncertainties subjected to either deterministic or random excitation. The parameter uncertainties are modeled as random variables or random fields, and are assumed to be time-independent. The new method is an extension of the deterministic finite element method to the space of random functions.\n\nFirst, the general formulation of the method is developed, in the case where the excitation is deterministic in time. Next, the application of this formulation to systems satisfying the one-dimensional wave equation with uncertainty in their physical properties is described. A particular physical conceptualization of this equation is chosen for study, and some engineering applications are discussed in both an earthquake ground motion and a structural context.\n\nFinally, the formulation of the new method is extended to include cases where the excitation is random in time. Application of this formulation to the random response of a primary-secondary system is described. It is found that parameter uncertainties can have a strong effect on the system response characteristics.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1989.EERL-89-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1989.EERL-89-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8902.pdf", "url": "https://authors.library.caltech.edu/records/8n9eb-yxy63/files/8902.pdf" }, "pub_year": "2001", "author_list": "Jensen, Hector A." }, { "id": "https://authors.library.caltech.edu/records/nbedm-9d254", "eprint_id": 26391, "eprint_status": "archive", "datestamp": "2023-08-19 23:11:10", "lastmod": "2024-01-13 05:30:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Papadimitriou-Costas", "name": { "family": "Papadimitriou", "given": "Konstantinos" }, "orcid": "0000-0002-9792-0481" } ] }, "title": "Stochastic characterization of strong ground motion and applications to structural response", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1991: PB-91-170217/AS\n\nAccepted Version - 9003.pdf
", "abstract": "This study addresses the problem of characterizing strong ground motion for the purpose of computing the dynamic response of structures to earthquakes. A new probabilistic ground motion model is proposed which can act as an interface between ground motion prediction studies and structural response studies. The model is capable of capturing, with at most nine parameters, all those features of the ground acceleration history which have an important influence on the dynamic response of linear and nonlinear structures, including the amplitude and frequency content nonstationarities of the shaking. Using a Bayesian probabilistic framework, a simple and effective statistical method is developed for extracting the \"optimal\" model from an actual accelerogram. The proposed ground motion model can be efficiently applied in simulations as well as analytical response and reliability studies of linear and inelastic structures.\n\nThe random response of linear and nonlinear oscillators subjected to the proposed stochastic excitation is considered. The nonlinearity of the oscillator is accounted for by equivalent linearization. A formulation is developed which approximates the original lengthy expressions for the second-moment statistics of the transient response by much simpler expressions. The results provide insight into the characteristics of the nonstationary response and the effect of the ground motion nonstationarities. It is found that the temporal nonstationarity in the frequency content of the ground motion significantly influences the response of both linear and nonlinear structural models. Simulations are also used to study the sensitivity of inelastic structural response parameters to the details of the ground motion which are left \"random\" by the model. The results can also be used to provide a quantitative assessment of the expected structural damage associated with the ground motion described by the model.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1990.EERL-90-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1990.EERL-90-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9003.pdf", "url": "https://authors.library.caltech.edu/records/nbedm-9d254/files/9003.pdf" }, "pub_year": "2001", "author_list": "Papadimitriou, Konstantinos" }, { "id": "https://authors.library.caltech.edu/records/t3kn3-5be07", "eprint_id": 26389, "eprint_status": "archive", "datestamp": "2023-08-19 22:41:42", "lastmod": "2024-01-13 05:30:34", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hou-Zhikun", "name": { "family": "Hou", "given": "Zhikun" } } ] }, "title": "Nonstationary response of structures and its application to earthquake engineering", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1990: PB-91-170092\n\nAccepted Version - 9001.pdf
", "abstract": "This thesis presents a simplified state-variable method to solve for the nonstationary response of linear MDOF systems subjected to a modulated stationary excitation in both time and frequency domains. The resulting covariance matrix and evolutionary spectral density matrix of the response may be expressed as a product of a constant system matrix and a time-dependent matrix, the latter can be explicitly evaluated for most envelopes currently prevailing in engineering. The stationary correlation matrix of the response may be found by taking the limit of the covariance response when a unit step envelope is used. The reliability analysis can then be performed based on the first two moments of the response obtained.\n\nThe method presented facilitates obtaining explicit solutions for general linear MDOF systems and is flexible enough to be applied to different stochastic models of excitation such as the stationary models, modulated stationary models, filtered stationary models, and filtered modulated stationary models and their stochastic equivalents including the random pulse train model, filtered shot noise, and some ARMA models in earthquake engineering. This approach may also be readily incorporated into finite element codes for random vibration analysis of linear structures.\n\nA set of explicit solutions for the response of simple linear structures subjected to modulated white noise earthquake models with four different envelopes are presented as illustration. In addition, the method has been applied to three selected topics of interest in earthquake engineering, namely, nonstationary analysis of primary-secondary systems with classical or nonclassical dampings, soil layer response and related structural reliability analysis, and the effect of the vertical components on seismic performance of structures. For all the three cases, explicit solutions are obtained, dynamic characteristics of structures are investigated, and some suggestions are given for aseismic design of structures.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1990.EERL-90-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1990.EERL-90-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9001.pdf", "url": "https://authors.library.caltech.edu/records/t3kn3-5be07/files/9001.pdf" }, "pub_year": "2001", "author_list": "Hou, Zhikun" }, { "id": "https://authors.library.caltech.edu/records/pkgqn-mvm75", "eprint_id": 26384, "eprint_status": "archive", "datestamp": "2023-08-19 19:47:11", "lastmod": "2024-01-13 05:30:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peng-Chia-Yen", "name": { "family": "Peng", "given": "Chia-Yen" } } ] }, "title": "Generalized modal identification of linear and nonlinear dynamic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1988: PB-89-194419/AS\n\nAccepted Version - 8705.pdf
", "abstract": "This dissertation is concerned with the problem of determining the dynamic characteristics of complicated engineering systems and structures from the measurements made during dynamic tests or natural excitations. Particular attention is given to the identification and modeling of the behavior of structural dynamic systems in the nonlinear hysteretic response regime. Once a model for the system has been identified, it is intended to use this model to assess the condition of the system and to predict the response to future excitations.\n\nA new identification methodology based upon a generalization of the method of modal identification for multi-degree-of-freedom dyna1mcal systems subjected to base motion is developed. The situation considered herein is that in which only the base input and the response of a small number of degrees-of-freedom of the system are measured. In this method, called the generalized modal identification method, the response is separated into \"modes\" which are analogous to those of a linear system. Both parametric and nonparametric models can be employed to extract the unknown nature, hysteretic or nonhysteretic, of the generalized restoring force for each mode.\n\nIn this study, a simple four-term nonparametric model is used first to provide a nonhysteretic estimate of the nonlinear stiffness and energy dissipation behavior. To extract the hysteretic nature of nonlinear systems, a two-parameter distributed element model is then employed. This model exploits the results of the nonparametric identification as an initial estimate for the model parameters. This approach greatly improves the convergence of the subsequent optimization process.\n\nThe capability of the new method is verified using simulated response data from a three-degree-of-freedom system. The new method is also applied to the analysis of response data obtained from the U.S.-Japan cooperative pseudo-dynamic test of a full-scale six-story steel-frame structure.\n\nThe new system identification method described has been found to be both accurate and computationally efficient. It is believed that it will provide a useful tool for the analysis of structural response data.", "date": "2001-10-15", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1987.EERL-87-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1987.EERL-87-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8705.pdf", "url": "https://authors.library.caltech.edu/records/pkgqn-mvm75/files/8705.pdf" }, "pub_year": "2001", "author_list": "Peng, Chia-Yen" }, { "id": "https://authors.library.caltech.edu/records/dvabn-af058", "eprint_id": 26374, "eprint_status": "archive", "datestamp": "2023-08-19 17:47:23", "lastmod": "2024-01-13 05:30:12", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pak-Ronald-Y-S", "name": { "family": "Pak", "given": "Ronald Y. S" } } ] }, "title": "Dynamic response of a partially embedded bar under transverse excitations", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-87-232856/A06\n\nAccepted Version - 8504.pdf
", "abstract": "This dissertation is concerned with the dynamic response of a finite flexible bar partially embedded in a half-space, under transverse loadings. The loadings are applied at the unembedded end of the bar and may, in general, be a combination of time-harmonic shear and moment. The problem is intended to serve as a fundamental idealization for the dynamic analysis of piles or other embedded foundations whose flexibilities are not negligible.\n\nBy treating the bar as a one-dimensional structure and the half-space as a three-dimensional elastic continuum, the interaction problem is formulated as a Fredholm integral equation of the second kind. The essential tool required in the formulation is a group of Green's functions which describe the response of an elastic half-space to a finite, distributed, buried source which acts in the lateral direction. By means of a technique developed for a class of three-dimensional asymmetric wave propagation problems, the Green's functions are derived as integral representations. A numerical procedure for the computation of the semi-infinite Hankel-type integrals involved is presented which is free of the basic difficulties commonly encountered in such problems. Owing to the special nature of the kernel function, a numerical scheme which contains the essence of quadrature and collocation techniques is developed for the solution of the governing integral equation. Selected results for the interaction problem are presented to illustrate various basic features of the solution. In addition to furnishing the compliance functions commonly used in soil-structure interaction studies, the solution should prove useful in providing a basis for the assessment and improvement of approximate and numerical models currently employed for such analyses.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1985.EERL-85-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1985.EERL-85-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8504.pdf", "url": "https://authors.library.caltech.edu/records/dvabn-af058/files/8504.pdf" }, "pub_year": "2001", "author_list": "Pak, Ronald Y. S" }, { "id": "https://authors.library.caltech.edu/records/qs1xz-qd871", "eprint_id": 26379, "eprint_status": "archive", "datestamp": "2023-08-19 18:50:51", "lastmod": "2024-01-13 05:30:19", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moser-Michael-Anthony", "name": { "family": "Moser", "given": "Michael Anthony" } } ] }, "title": "The response of stick-slip systems to random seismic excitation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1987: PB-89-194427/AS\n\nAccepted Version - 8603.pdf
", "abstract": "This thesis examines the response of stick-slip, or frictional, systems to harmonic and random excitation. Two frictional models are considered: constant slip force, or Coulomb, friction, and displacement dependent slip force, used to model a caster, or pivoting wheel. The response to harmonic excitation of systems exhibiting both frictional models is determined using the method of slowly varying parameters. Changes in the response amplitude of both systems caused by the addition of a linear centering mechanism are also examined.\n\nThe response of the system with displacement dependent slip force is examined under Gaussian mean zero white noise excitation using the generalized equivalent linearization method. It is shown that a lower bound is obtained from the Coulomb friction system's response.\n\nFor filtered random excitation, linearization methods are shown to predict erroneous displacement trends for the Coulomb system when the input has no spectral content at zero frequency. When the excitation is modeled as a Poisson pulse process, an approximate method exhibiting the proper displacement trends can be constructed. The method is shown to be accurate over a broad range of input parameters if overlaps in the input pulses are considered. A set of excitation parameters consistent with seismic events is then used to estimate final rms displacements as a function of coefficient of friction.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1986.EERL-86-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1986.EERL-86-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8603.pdf", "url": "https://authors.library.caltech.edu/records/qs1xz-qd871/files/8603.pdf" }, "pub_year": "2001", "author_list": "Moser, Michael Anthony" }, { "id": "https://authors.library.caltech.edu/records/3mz0d-41a77", "eprint_id": 26377, "eprint_status": "archive", "datestamp": "2023-08-19 18:34:29", "lastmod": "2024-01-13 05:30:15", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peek-Ralf", "name": { "family": "Peek", "given": "Ralf" } } ] }, "title": "Analysis of unanchored liquid storage tanks under seismic loads", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1986: PB-87-232872/A12\n\nAccepted Version - 8601.pdf
", "abstract": "Because of cost, cylindrical, ground supported liquid storage tanks are often not fixed to their foundation, even in seismic areas. For such an unanchored tank made of steel, the weight of the cylindrical shell is mostly insufficient ' to prevent local uplift due to seismic overturning moments. Although, for properly designed connecting pipes, uplift itself is not a problem, it results in larger vertical compressive stresses in the tank wall at the base, opposite to where the uplift occurs. These compressive stresses have often caused buckling, even in earthquakes which did not cause much damage to other structures.\n\nVarious investigators have studied the behavior of unanchored tanks experimentally, but, due to the complexity of the problem, so far very little theoretical work has been done. Two methods of analysis for static lateral loads are presented: An approximate one in which the restraining action of the base plate is modeled by nonlinear Winkler springs, and a more comprehensive one in which the two dimensional nonlinear contact problem is solved by the finite difference energy method. The theoretical results are compared with existing experimental results and with the approach from current U.S. design standards. The theoretical peak compressive stresses are in good agreement with the experimental results, but in some cases exceed those calculated by the code method by more than 100%.\nFinally, a new design concept, by which the tank wall is preuplifted all around its circumference by inserting a ring filler is described. It will be shown theoretically and experimentally that this preuplift method substantially improves the lateral load capacity.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1986.EERL-86-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1986.EERL-86-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8601.pdf", "url": "https://authors.library.caltech.edu/records/3mz0d-41a77/files/8601.pdf" }, "pub_year": "2001", "author_list": "Peek, Ralf" }, { "id": "https://authors.library.caltech.edu/records/wz6fb-7qq43", "eprint_id": 26380, "eprint_status": "archive", "datestamp": "2023-08-19 19:34:44", "lastmod": "2024-01-13 05:30:21", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jayakumar-Paramsothy", "name": { "family": "Jayakumar", "given": "Paramsothy" } } ] }, "title": "Modeling and identification in structural dynamics", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1987: PB-89-194146/AS\n\nAccepted Version - 8701.pdf
", "abstract": "Analytical modeling of structures subjected to ground motions is an important aspect of fully dynamic earthquake-resistant design. In general, linear models are only sufficient to represent structural responses resulting from earthquake motions of small amplitudes. However, the response of structures during strong ground motions is highly nonlinear and hysteretic.\n\nSystem identification is an effective tool for developing analytical models from experimental data. Testing of full-scale prototype structures remains the most realistic and reliable source of inelastic seismic response data. Pseudo-dynamic testing is a recently developed quasi-static procedure for subjecting full-scale structures to simulated earthquake response. The present study deals with structural modeling and the determination of optimal linear and nonlinear models by applying system identification techniques to elastic and inelastic pseudo-dynamic data from a full-scale, six-story steel structure.\n\nIt is shown that the feedback of experimental errors during the pseudo-dynamic tests significantly affected the higher modes and led to an effective negative damping for the third mode. The contributions of these errors are accounted for and the small-amplitude modal properties of the test structure are determined. These properties are in agreement with the values obtained from a shaking table test of a 0.3 scale model.\n\nThe nonlinear hysteretic behavior of the structure during strong ground motions is represented by a general class of Masing models. A simple model belonging to this class is chosen with parameters which can be estimated theoretically, thereby making this type of model potentially useful during the design stages. The above model is identified from the experimental data and then its prediction capability and application in seismic design and analysis are examined.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1987.EERL-87-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1987.EERL-87-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8701.pdf", "url": "https://authors.library.caltech.edu/records/wz6fb-7qq43/files/8701.pdf" }, "pub_year": "2001", "author_list": "Jayakumar, Paramsothy" }, { "id": "https://authors.library.caltech.edu/records/7509e-4x003", "eprint_id": 26378, "eprint_status": "archive", "datestamp": "2023-08-19 18:11:05", "lastmod": "2024-01-13 05:30:17", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paparizos-Leonidas-G", "name": { "family": "Paparizos", "given": "Leonidas G" } } ] }, "title": "Some observations on the random response of hysteretic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1986: PB-88235668/CC\n\nAccepted Version - 8602.pdf
", "abstract": "In this thesis, the nature of hysteretic response behavior of structures subjected to strong seismic excitation, is examined. The earthquake ground motion is modeled as a stochastic process and the dependence of the response on system and excitation parameters, is examined. Consideration is given to the drift of structural systems and its dependence on the low frequency content of the earthquake spectrum. It is shown that commonly used stochastic excitation models, are not able to accurately represent the low frequency content of the excitation. For this reason, a stochastic model obtained by filtering a modulated white noise signal through a second order linear filter is used in this thesis.\n\nA new approach is followed in the analysis of the elasto-plastic system. The problem is formulated in terms of the drift, defined as the sum of yield increments associated with inelastic response. The solution scheme is based on the properties of discrete Markov proms models of the yield increment process, while the yield increment statistics are expressed in terms of the probability density of the velocity and elastic component of the displacent response. Using this approach, an approximate exponential and Rayleigh distribution for the yield increment and yield duration, respectively, are established. It is suggested that, for duration of stationary seismic excitation of practical significance, the drift can be considered as Brownian motion. Based on this observation, the approximate Gaussian distribution and the linearly divergent mean square value of the process, as well as an expression for the probability distribution of the peak drift response, are obtained. The validation of these properties is done by means of a Monte Carlo simulation study of the random response of an elasto-plastic system.\n\nBased on this analysis, the first order probability density and first passage probabilities for the drift are calculated from the probability density of the velocity and elastic component of the response, approximately obtained by generalized equivalent linearization. It is shown that the drift response statistics are strongly dependent on the normalized characteristic frequency and strength of the excitation, while a weaker dependence on the bandwidth of excitation is noted.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1986.EERL-86-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1986.EERL-86-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8602.pdf", "url": "https://authors.library.caltech.edu/records/7509e-4x003/files/8602.pdf" }, "pub_year": "2001", "author_list": "Paparizos, Leonidas G" }, { "id": "https://authors.library.caltech.edu/records/09hte-ej354", "eprint_id": 26381, "eprint_status": "archive", "datestamp": "2023-08-19 19:50:09", "lastmod": "2024-01-13 05:30:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dur\u00f3n-Ziyad-Hassan", "name": { "family": "Dur\u00f3n", "given": "Ziyad H." } } ] }, "title": "Experimental and finite element studies of a large arch dam", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1988: PB-89-194435/AS\n\nAccepted Version - 8702.pdf
", "abstract": "Forced vibration field tests and finite element studies have been conducted on Morrow Point (arch) Dam in order to investigate dynamic dam-water interaction and water compressibility. Design of the data acquisition system incorporates several special features to retrieve both amplitude and phase of the response in a low signal to noise environment. These features contributed to the success of the experimental program which, for the first time, produced field evidence of water compressibility; this effect seems to play a significant role only in the symmetric response of Morrow Point Dam in the frequency range examined. In the accompanying analysis, frequency response curves for measured accelerations and water pressures as well as their resonating shapes are compared to predictions from the current state-of-the-art finite element model for which water compressibility is both included and neglected. Calibration of the numerical model employs the antisymmetric response data since they are only slightly affected by water compressibility, and, after calibration, good agreement to the data is obtained whether or not water compressibility is included. In the effort to reproduce the symmetric response data, on which water compressibility has a significant influence, the calibrated model shows better correlation when water compressibility is included, but the agreement is still inadequate. Similar results occur using data obtained previously by others at a low water level. A successful isolation of the fundamental water resonance from the experimental data shows significantly different features from those of the numerical water model, indicating possible inaccuracy in the assumed geometry and/or boundary conditions for the reservoir. However, the investigation does suggest possible directions in which the numerical model can be improved.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1987.EERL-87-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1987.EERL-87-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8702.pdf", "url": "https://authors.library.caltech.edu/records/09hte-ej354/files/8702.pdf" }, "pub_year": "2001", "author_list": "Dur\u00f3n, Ziyad H." }, { "id": "https://authors.library.caltech.edu/records/apv82-y8b87", "eprint_id": 26373, "eprint_status": "archive", "datestamp": "2023-08-19 17:34:24", "lastmod": "2024-01-13 05:30:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jeong-Garrett-Duane", "name": { "family": "Jeong", "given": "Garrett Duane" } } ] }, "title": "Cumulative damage of structures subjected to response spectrum consistent random processes", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-86-100807\n\nAccepted Version - 8503.pdf
", "abstract": "A theoretical analysis of the effect of duration on the damage of structures subjected to earthquakes is presented. Earthquake excitation is modeled as a nonstationary random process. Estimates of the firstpassage probability of a simple oscillator are employed to choose modulated Gaussian random processes consistent with a prescribed response spectrum. The response spectrum is assumed to be specified independent of the duration. Expressions for the mean damage of a structure are derived using an approach similar to the Miner-Palmgren rule for failure caused by cyclic loads. The expected damage expressions are then evaluated for a structure subjected to modulated Gaussian random processes of varying duration.\n\nTwo types of structures are examined: a steel structure and a reinforced concrete structure. Results are presented for systems with constant linear stiffness and a particular form of softening behavior. The nonlinearity of the softening system is accounted for by statistical linearization. The level of expected damage is found to be a strong function of both the duration of the excitation and the ductility of the response.", "date": "2001-10-12", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1985.EERL-85-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1985.EERL-85-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8503.pdf", "url": "https://authors.library.caltech.edu/records/apv82-y8b87/files/8503.pdf" }, "pub_year": "2001", "author_list": "Jeong, Garrett Duane" }, { "id": "https://authors.library.caltech.edu/records/4a0c1-80y20", "eprint_id": 26372, "eprint_status": "archive", "datestamp": "2023-08-19 16:27:52", "lastmod": "2024-01-13 05:30:08", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Maragakis-Emmanuel", "name": { "family": "Maragakis", "given": "Emmanuel" } } ] }, "title": "A model for the rigid body motions of skew bridges", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-85-248433/AS\n\nAccepted Version - 8502.pdf
", "abstract": "This thesis investigates the rigid body motions of skew bridges, concentrating on the in-plane translational and rotational displacements of the bridge deck induced by impact between the deck and the abutments. Experience in the San Fernando Earthquake of February 9, 1971 demonstrates that this feature is particularly important for skew bridges.\n\nA simple model, in which the bridge deck is represented by a rigid rod restricted by column and abutment springs is examined first. This model illustrates the mechanism by which in-plane rotational vibrations is triggered after the closure of the gap between the bridge deck and the abutment. It also shows that the force-deflection relations of the columns and the abutments are particularly important features for the response of the bridge. methods for the exact and approximate estimation of the elastic stiffness of elastically founded, tapered bridge columns with octagonal cross section are presented next. The methods are applied to a bridge used later as an example. In addition, the yielding of the columns is examined and the force-deflection relations for bending about two orthogonal axes are estimated.\n\nThe abutments are treated as rigid bodies and the soil embankments as Winkler Foundations with elastic spring constants increasing with depth. For the examination of the yielding of soil the Rankine theory is used. Based on these assumptions an approximate force-deflection relation for the abutments is constructed.\n\nThe response of a more complicated bridge model applied to a bridge near Riverside, California is examined at the end of the thesis and examples of the results are given. This model, in which the bridge deck is still represented as a rigid rod, has three in-plane degrees of freedom: two orthogonal displacements and a rotation, and is capable of capturing many of the more important features of the nonlinear, yielding response of skew bridges during strong earthquake shaking.", "date": "2001-10-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-85-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-85-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8502.pdf", "url": "https://authors.library.caltech.edu/records/4a0c1-80y20/files/8502.pdf" }, "pub_year": "2001", "author_list": "Maragakis, Emmanuel" }, { "id": "https://authors.library.caltech.edu/records/fayzh-ph088", "eprint_id": 26278, "eprint_status": "archive", "datestamp": "2023-08-19 16:07:56", "lastmod": "2024-01-13 05:29:41", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Moh-jiann", "name": { "family": "Huang", "given": "Moh-jiann" } } ] }, "title": "Investigation of local geology effects on strong earthquake ground motions", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1984: PB-84-161488\n\nAccepted Version - 8303.pdf
", "abstract": "Accelerograms recorded at four stations in the Pasadena area during the 1971 San Fernando, the 1970 Lytle Creek, the 1968 Borrego Mountain and the 1952 Kern County earthquakes are analyzed to investigate local geology effects on strong earthquake ground motions. Spatial variations of the ground motions at two nearby stations are also investigated. It is found that the ground motions in this area caused by the local geology effects depend an the 3-dimensional configuration of the local geology and the direction of arriving seismic waves, Local geology effects are less evident on the leading portions of the accelerograms than the trailing portions, indicating the effects of local geology on surface wave propagations. Comparison of the Fourier amplitudes of the motions recorded at the same station during different earthquakes shows that there are no significant spectral peaks can be identified as site periods. Hence, it is not appropriate to characterize such local sites by a site period.\n\nA two-dimensional model considering inclined propagating P and S waves in a horizontal-layered structure, which is more realistic and closer to the actual seismic environment within a local geology than the one-dimensional model of vertically propagating waves, is studied. The transfer functions between the free surface and the half-space outcrop for a single incident P, SV or SH wave from the half-space at an incident angle are defined and derived by a matrix method. Two numerical examples are given to demonstrate the effects of incident angle and material damping on the transfer function. It is found that the transfer function between the free surface motions and the bedrock outcrop motions to multiple incident waves having different amplitudes, angles and arrival times is quite different from that for a single incident wave. Completely satisfactory results can not be expected when using the analytical model for evaluating the local geology effects on the motions during a nearby shallow-focus earthquake for which seismic waves emitted from different parts of the fault win approach the bedrock from different directions and at different angles.\n\nThe analytical model for assessing local geology effects is evaluated in the light of the data recorded at stations in the Pasadena area during the 1971 San Fernando earthquake. The observed site transfer functions between the alluvial and the rock sites are obtained and compared with the computed results from a two-dimensional model with 7-layers overlying a half-space. Values of model parameters are optimally adjusted to give a best least-squares fit between computed and observed amplitude ratios. It is concluded that the analytical model oversimplifies the local geological structure in the Pasadena area and the actual seismic environment in the area during the 1971 San Fernando earthquake.\n\nIt is concluded from these studies that the effects of the source mechanism and the seismic wave travel paths upon the site ground motion can be comparable to the effect of the local geology. The characteristics of the source mechanism, such as type of faulting, direction of fault-slip propagation, nature of stress drop across the fault surface, orientation of fault. depth beneath ground surface, etc., can appreciably influence the ground motion at the site. Also, the travel path can have a significant effect through influencing the types of waves that reach the site, and the directions of approach of the waves. The results of this study indicate that a better understanding of the spatial variation of ground motions, of the role played by different types of waves and their contributions to an accelerogram, and of the propagation directions of the waves is needed for assessing local geology effects on earthquake ground motions. A local array is desirable to provide data for giving a reasonably complete picture of the nature of ground motions in a local area.", "date": "2001-10-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1983.EERL-83-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1983.EERL-83-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8303.pdf", "url": "https://authors.library.caltech.edu/records/fayzh-ph088/files/8303.pdf" }, "pub_year": "2001", "author_list": "Huang, Moh-jiann" }, { "id": "https://authors.library.caltech.edu/records/6802d-f6x84", "eprint_id": 26370, "eprint_status": "archive", "datestamp": "2023-08-19 16:27:47", "lastmod": "2024-01-13 05:30:06", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cifuentes-Arturo-O", "name": { "family": "Cifuentes", "given": "Arturo O." } } ] }, "title": "System Identification of Hysteretic Structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-240489/AS14\n\nAccepted Version - 8404.pdf
", "abstract": "This thesis is concerned with the earthquake response of hysteretic structures subjected to strong ground acceleration. Several earthquake records corresponding to different instrumented buildings are analyzed. Based on these observations, a new model for the dynamic behavior of reinforced concrete buildings is proposed. In addition, a suitable system identification algorithm to be used with this new model is introduced. This system identification algorithm is based upon matching the restoring force behavior of the structure rather than the time history of the response. As a consequence, the new algorithm exhibits significant advantages from a computational point of view. Some numerical examples using actual earthquake data are discussed.", "date": "2001-10-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-84-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-84-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8404.pdf", "url": "https://authors.library.caltech.edu/records/6802d-f6x84/files/8404.pdf" }, "pub_year": "2001", "author_list": "Cifuentes, Arturo O." }, { "id": "https://authors.library.caltech.edu/records/gwtm0-zxq57", "eprint_id": 26246, "eprint_status": "archive", "datestamp": "2023-08-20 00:02:17", "lastmod": "2024-01-13 05:29:26", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Katafygiotis-L-S", "name": { "family": "Katafygiotis", "given": "Lambros S." } } ] }, "title": "Treatment of model uncertainties in structural dynamics", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1991\n\nAccepted Version - 9101.pdf
", "abstract": "The uncertainties related to the modeling of the dynamic behavior of a structure are analyzed using a probabilistic approach.\n\nFirst, the case of preliminary design is addressed, where the structure has not yet been built. A new efficient and accurate numerical method is proposed to investigate the resulting uncertainties in the structural response due to uncertainties in the modeling process, where engineering judgement is used to quantify the latter uncertainties.\n\nSecond, the case where records of measured structural response are available to reduce the uncertainties in the structural models is addressed. The posterior probability distribution of the uncertain parameters is found to be very peaked at the values of some optimal parameters. These optimal parameters can be obtained by minimizing a positive- definite measure-of-fit function. A new efficient minimization algorithm is proposed to resolve difficulties in convergence of existing methods. The identifiability of the optimal parameters is also addressed. The problem of finding the whole set of the optimal models that have the same output at the observed degrees of freedom is resolved for the first time, by presenting an algorithm which methodically and efficiently searches the parameter space.", "date": "2001-10-08", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1991.EERL-91-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1991.EERL-91-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9101.pdf", "url": "https://authors.library.caltech.edu/records/gwtm0-zxq57/files/9101.pdf" }, "pub_year": "2001", "author_list": "Katafygiotis, Lambros S." }, { "id": "https://authors.library.caltech.edu/records/0b949-cmp09", "eprint_id": 26360, "eprint_status": "archive", "datestamp": "2023-08-19 13:29:51", "lastmod": "2024-01-13 05:29:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-Martin", "name": { "family": "Cohen", "given": "Martin" } } ] }, "title": "Silent boundary methods for transient wave analysis", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1981: PB-82-201831\n\nAccepted Version - 8009.pdf
", "abstract": "This thesis sets forth a dynamic model, designed to absorb infinitely radiating waves in a finite, computational grid. The analysis is primarily directed toward the problem of sail-structure interaction, where energy propagates from a region near a structure, outward toward the boundaries.\n\nThe proposed method, called the extended-paraxial boundary, is derived from one-directional, wave theories that have been propounded by other authors. In this thesis, the theory is presented from a more general viewpoint and is studied for its stability properties. This work suggests some modifications to the method as it was first presented. Innovations are also put forward in the boundary's implementation for finite element calculations. These alterations render the boundary an effective wave absorber.\n\nThe extended-paraxial boundary is then compared, both analytically and numerically, with two other transmitting (or silent) boundaries currently available -- the standard-viscous and unified-viscous methods. The analytical results indicate that the extended-paraxial boundary enjoys a distinct advantage in canceling wave reflections; actual numerical tests revealed a small superiority over the viscous approaches.\n\nVarious issues are also discussed as they relate to the silent boundaries. These include Rayleigh waves, spherically symmetric and axially symmetric waves, nonlinear waves, anisotropic media, and numerical stability.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-09", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-09", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8009.pdf", "url": "https://authors.library.caltech.edu/records/0b949-cmp09/files/8009.pdf" }, "pub_year": "2001", "author_list": "Cohen, Martin" }, { "id": "https://authors.library.caltech.edu/records/5zggf-81w22", "eprint_id": 26361, "eprint_status": "archive", "datestamp": "2023-08-19 13:40:26", "lastmod": "2024-01-13 05:29:58", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-Shawn-Anthony", "name": { "family": "Hall", "given": "Shawn Anthony" }, "orcid": "0000-0001-8295-6521" } ] }, "title": "Vortex-induced vibrations of structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1981: PB-82-201849\n\nAccepted Version - 8101.pdf
", "abstract": "Vortex-induced oscillations. often of concern when a bluff structure is exposed to fluid cross-flow, are considered herein using a semi-empirical modeling approach. Based an the fluid momentum theorem, the model involves a highly simplified abstraction of the complex flow field. and major assumptions concerning the nature of the coupling between the fluid and the oscillating structure.\n\nThree prototype problems are studied. including harmonically forced cylinders, spring-mounted cylinders. and taut elastic cables; in each case the structure is assumed to be of circular cross-section and situated in a uniform cross-flow. Only oscillations transverse to the flow are considered. The problem of modal interaction for elastic cables, typically of interest when the fluid flow excites high-mode-number resonances is given particular attention.\n\nThe model produces a set of nonlinear, ordinary differential equations describing the coupled fluid/structure oscillations. Steady-state oscillatory solutions to these equations are found analytically and are examined for stability. Using various regression techniques, the steady-state solutions are then fit to experimental data for forced and spring-mounted cylinders. Finally, the model's predictions for elastic cables are used to postulate a qualitative picture of modal interaction, certain features of which have been observed experimentally.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-81-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-81-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8101.pdf", "url": "https://authors.library.caltech.edu/records/5zggf-81w22/files/8101.pdf" }, "pub_year": "2001", "author_list": "Hall, Shawn Anthony" }, { "id": "https://authors.library.caltech.edu/records/egy03-jq111", "eprint_id": 26357, "eprint_status": "archive", "datestamp": "2023-08-19 13:23:47", "lastmod": "2024-01-13 05:29:52", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Wing-Kam", "name": { "family": "Liu", "given": "Wing Kam" } } ] }, "title": "Development of finite element procedures for fluid-structure interaction", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1981: PB 184078\n\nAccepted Version - 8006.pdf
", "abstract": "In this thesis the development of finite element procedures for fluid-structure interaction problems is presented. The areas upon which attention is focused are: numerical transient algorithms which emphasize implicit-explicit finite element concepts; finite element kinematical descriptions for modelling fluid subdomains in fluidstructure interaction problems; finite element methodology for nearly incompressible fluids and solids, and beam, plate and shell structures based upon theories which include transverse shear deformations; and finite rotation effects in numerical integration of rate constitutive equations arising in large-deformation analysis. All these nonlinear methodologies have been integrated into a working finite element computer code. A number of numerical examples are presented to demonstrate the effectiveness of these approaches.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8006.pdf", "url": "https://authors.library.caltech.edu/records/egy03-jq111/files/8006.pdf" }, "pub_year": "2001", "author_list": "Liu, Wing Kam" }, { "id": "https://authors.library.caltech.edu/records/w2acz-f1010", "eprint_id": 26368, "eprint_status": "archive", "datestamp": "2023-08-19 15:57:28", "lastmod": "2024-01-13 05:30:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jain-Sudhir-Kumar", "name": { "family": "Jain", "given": "Sudhir Kumar" } } ] }, "title": "Analytical models for the dynamics of buildings", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1983: PB-84-161009\n\nAccepted Version - 8302.pdf
", "abstract": "This thesis investigates the significance of in-plane floor flexibility on the dynamics of buildings, and develops analytical models for structures that have flexible floor diaphragms. Experience with past earthquakes demonstrates that this feature is particularly important for long, narrow buildings and buildings with stiff end walls. In the method developed in this study, the equations of motion and appropriate boundary conditions for various elements of the structure are written in a single coordinate system and then are solved exactly.\n\nOne- and two-story buildings with end walls are analyzed by treating their floors and walls as bending and shear beams, respectively. The resulting equations of motion and the boundary conditions are solved to obtain the dynamic properties of the structure. The expected low torsional stiffness of the end walls or frames is confirmed by analysis of a single-story example structure. Study of a similar two-story building showed that the first two modes, dominated by the floor and the roof vibrations, make the largest contributions to the total base shear in the structure.\n\nFloors of multistory buildings with end walls (or frames) are idealized as equivalent, distributed beams while the walls or frames are treated as bending or shear beams. Analysis of a nine-story building showed that the structure possesses several lower modes in which floors vibrate essentially as pinned-pinned beams.\n\nBuildings with large numbers of uniform stories and frames (or walls) are treated as vertically-oriented anisotropic plates. It is concluded that the floors in such buildings can be assumed rigid for seismic analysis, since the modes involving floor deformations are not excited by uniform ground motion.\n\nThe approach can be generalized further to study more complex structures. An example is the Imperial County Services Building, which has two and walls in the upper stories and several walls in the ground story. The analytical model of this building predicts several important features of the complex dynamic behavior of the structure.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1983.EERL-83-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1983.EERL-83-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8302.pdf", "url": "https://authors.library.caltech.edu/records/w2acz-f1010/files/8302.pdf" }, "pub_year": "2001", "author_list": "Jain, Sudhir Kumar" }, { "id": "https://authors.library.caltech.edu/records/3vy1y-6kt21", "eprint_id": 26364, "eprint_status": "archive", "datestamp": "2023-08-19 15:01:38", "lastmod": "2024-01-13 05:30:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Albert-Niu", "name": { "family": "Lin", "given": "Albert Niu" } } ] }, "title": "Experimental observations of the effect of foundation embedment on structural response", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1982: PB-84-163252\n\nAccepted Version - 8201.pdf
", "abstract": "Ambient, ring-down, and forced vibration tests were used to determine the effect of foundation embedment on the response of a one-story model structure 10 ft square in plan and 11.4 ft high. The tests, conducted at the full-, half- and unembedded foundation conditions, led to the identification of the fundamental translatory mode in the primary (east-west) and secondary (north-south) directions, and two torsional modes. The forced vibration consisted of horizontally incident SH-waves generated at an excitation structure located 47.5 ft (center-to-center) away. During these tests, detailed measurements of the near-field ground motion and modal displacement ratios were obtained at the fundamental mode in the primary direction. The displacement ratios were used to calculate the structural and foundation-soil stiffnesses and damping coefficients for comparison to theoretical results. Foundation embedment increased the model frequencies and decreased the contribution of the foundation motion to the overall displacement of the superstructure. For the fundamental mode response, which consisted of translatory and rocking motions, the resonant frequency predicted by lumped parameter analysis was higher than that measured experimentally by 25% for the unembedded case. While the experimental and theoretical fundamental mode shapes were in close agreement, the calculated effect of embedment on the response was less than that measured. These results were consistent with the comparison of the impedances and embedment factors. Serious discrepancies between analytical and experimental results were found for the case of torsion; a simple two-degree-of-freedom model was consistent only with the first of the two measured resonant frequencies.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1982.EERL-82-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1982.EERL-82-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8201.pdf", "url": "https://authors.library.caltech.edu/records/3vy1y-6kt21/files/8201.pdf" }, "pub_year": "2001", "author_list": "Lin, Albert Niu" }, { "id": "https://authors.library.caltech.edu/records/efh4y-npy68", "eprint_id": 26365, "eprint_status": "archive", "datestamp": "2023-08-19 15:14:10", "lastmod": "2024-01-13 05:30:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Botelho-Dirceu-Luiz-Rodrigues", "name": { "family": "Botelho", "given": "Dirceu Luiz Rodrigues" } } ] }, "title": "An empirical model for vortex-induced vibrations", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1983: PB-84-161157\n\nAccepted Version - 8202.pdf
", "abstract": "Through an analytical-empirical approach, the vortex-excited transverse oscillations of flexibly-mounted circular cylinders in a uniform flow is studied.\n\nA new model is derived, assuming spanwise constant flow velocity within the sub-critical range of Reynolds numbers and using only experimental data obtained from forced cylinders in water.\n\nThe steady-state response of flexibly-mounted cylinders is obtained as a function of the structural system and flow parameters and its stability is analyzed. Several characteristics observed experimentally and also present in the model response are discussed.\n\nThe resultant model's capability for predicting structural response for a wide range of fluid mediums is illustrated through comparisons between model predictions and results obtained experimentally from flexibly-mounted cylinders in air and in water.\n\nThis model developed is expected to yield better results for structures in water, by virtue of being based only on experimental results obtained in water.", "date": "2001-09-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1982.EERL-82-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1982.EERL-82-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8202.pdf", "url": "https://authors.library.caltech.edu/records/efh4y-npy68/files/8202.pdf" }, "pub_year": "2001", "author_list": "Botelho, Dirceu Luiz Rodrigues" }, { "id": "https://authors.library.caltech.edu/records/hvj11-9fq13", "eprint_id": 26353, "eprint_status": "archive", "datestamp": "2023-08-19 10:33:19", "lastmod": "2024-01-13 05:29:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gates-Nathan-Craig", "name": { "family": "Gates", "given": "Nathan Craig" } } ] }, "title": "The earthquake response of deteriorating systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1977: PB 271 090/AS\n\nAccepted Version - 7703.pdf
", "abstract": "This thesis is concerned with the earthquake response of deteriorating systems. A model for stiffness degrading or deteriorating systems is used to describe six different singledegree- of -freedom systems. A numerical investigation of the response of these six systems is performed using an ensemble of twelve earthquakes. The response is studied at nine nominal periods of oscillation. The numerical results are presented as response spectra corresponding to six different ductilities.\n\nAn approximate analytical method for calculating the earthquake response of deteriorating systems from a linear response spectrum is presented. The method, called the average stiffness and energy method, is based upon the premise that a linear system may be defined which is in some sense equivalent to the deteriorating system. The criterion for equivalence in this method is that the average stiffness of the deteriorating system be equal to the stiffness of the linear system and the average energy dissipated by the linear system be the same as the average energy dissipated by the deteriorating system.\n\nThe new analytical method is compared to existing methods. Comparison with the numerical results is also made. Based upon these comparisons, it is concluded that the average stiffness and energy method represents a significant improvement over currently available methods for predicting the earthquake response of deteriorating and nondeteriorating systems.", "date": "2001-09-24", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL-77-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL-77-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7703.pdf", "url": "https://authors.library.caltech.edu/records/hvj11-9fq13/files/7703.pdf" }, "pub_year": "2001", "author_list": "Gates, Nathan Craig" }, { "id": "https://authors.library.caltech.edu/records/d9dh3-vzs02", "eprint_id": 26329, "eprint_status": "archive", "datestamp": "2023-08-19 00:40:32", "lastmod": "2024-01-13 05:29:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gan-Wenshui", "name": { "family": "Gan", "given": "Wenshui" } } ] }, "title": "Earthquake response of steel braces and braced steel frames", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - 9606.pdf
", "abstract": "This thesis consists of three parts. Chapter 2 deals with the dynamic buckling behavior of steel braces under cyclic axial end displacement. Braces under such a loading condition belong to a class of \"acceleration magnifying\" structural components, in which a small motion at the loading points can cause large internal acceleration and inertia. This member-level inertia is frequently ignored in current studies of braces and braced structures. This chapter shows that, under certain conditions, the inclusion of the member-level inertia can lead to brace behavior fundamentally different from that predicted by the quasi-static method. This result is to have significance in the correct use of the quasi-static, pseudo-dynamic and static condensation methods in the simulation of braces or braced structures under dynamic loading. The strain magnitude and distribution in the braces are also studied in this chapter.\nChapter 3 examines the effect of column uplift on the earthquake response of braced steel frames and explores the feasibility of flexible column-base anchoring. It is found that fully anchored braced-bay columns can induce extremely large internal forces in the braced-bay members and their connections, thus increasing the risk of failures observed in recent earthquakes. Flexible braced-bay column anchoring can significantly reduce the braced bay member force, but at the same time also introduces large story drift and column uplift. The pounding of an uplifting column with its support can result in very high compressive axial force.\nChapter 4 conducts a comparative study on the effectiveness of a proposed non-buckling bracing system and several conventional bracing systems. The non-buckling bracing system eliminates buckling and thus can be composed of small individual braces distributed widely in a structure to reduce bracing force concentration and increase redundancy. The elimination of buckling results in a significantly more effective bracing system compared with the conventional bracing systems. Among the conventional bracing systems, bracing configurations and end conditions for the bracing members affect the effectiveness.\nThe studies in Chapter 3 and Chapter 4 also indicate that code-designed conventionally braced steel frames can experience unacceptably severe response under the strong ground motions recorded during the recent Northridge and Kobe earthquakes.", "date": "2001-09-05", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1996.EERL-96-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1996.EERL-96-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "9606.pdf", "url": "https://authors.library.caltech.edu/records/d9dh3-vzs02/files/9606.pdf" }, "pub_year": "2001", "author_list": "Gan, Wenshui" }, { "id": "https://authors.library.caltech.edu/records/bbjxj-7qy87", "eprint_id": 26312, "eprint_status": "archive", "datestamp": "2023-08-18 23:53:57", "lastmod": "2024-01-13 05:29:43", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Ching-Tung", "name": { "family": "Huang", "given": "Ching-Tung" } } ] }, "title": "On the dynamic response of nonlinear uncertain systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD., 1996\n\nAccepted Version - 9603.pdf
", "abstract": "This thesis presents an approach for performing second moment analyses of nonlinear dynamic systems with parameter uncertainty. The uncertain parameters are modeled as time-independent random variables. The set of orthogonal polynomials associated with the probability density function is used as the solution basis. When a deterministic excitation source is considered, the response variables are expanded in terms of a finite sum of these polynomials with time-dependent coefficients. The weighted residual method is employed to derive a set of deterministic nonlinear differential equations that can be solved numerically for evaluations of response statistics.\nThis solution approach is further extended to nonlinear continuous systems involving inhomogeneous random media. A discrete representation is obtained via a spatial discretization procedure for the continuous response variables as well as the random continuum. Thus, the continuous random system can then be treated as in the case of the discrete random systems. The solution approach is applied to a study of a nonlinear random shear-beam model subjected to a near-field earthquake ground motion.\nThe response uncertainty for nonlinear uncertain systems subjected to external stochastic excitation is also investigated. A general solution procedure based on equivalent linearization is presented. In this solution methodology, the instantaneous equivalent stiffness and damping matrices are approximated as quadratic random functions. The resulting Liapunov system with explicit random coefficients can then be solved using the newly developed solution approach. Applications to single-degree-of-freedom uncertain systems are given and the accuracy of the results is validated.", "date": "2001-08-30", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1996.EERL-96-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1996.EERL-96-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9603.pdf", "url": "https://authors.library.caltech.edu/records/bbjxj-7qy87/files/9603.pdf" }, "pub_year": "2001", "author_list": "Huang, Ching-Tung" }, { "id": "https://authors.library.caltech.edu/records/cmk2g-1pn29", "eprint_id": 26248, "eprint_status": "archive", "datestamp": "2023-08-19 05:47:28", "lastmod": "2024-01-13 05:29:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irfanoglu-Ayhan", "name": { "family": "Irfanoglu", "given": "Ayhan" }, "orcid": "0000-0001-8334-6717" } ] }, "title": "Structural design under seismic risk using multiple performance objectives", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2000\n\nAccepted Version - eerl2000-02.pdf
", "abstract": "Structural design is a decision-making process in which a wide spectrum of requirements, expectations, and concerns needs to be properly addressed. Engineering design criteria are considered together with societal and client preferences, and most of these design objectives are affected by the uncertainties surrounding a design. Therefore, realistic design frameworks must be able to handle multiple performance objectives and incorporate uncertainties from numerous sources into the process.\n\nIn this study, a multi-criteria based design framework for structural design under seismic risk is explored. The emphasis is on reliability-based performance objectives and their interaction with economic objectives. The framework has analysis, evaluation, and revision stages. In the probabilistic response analysis, seismic loading uncertainties as well as modeling uncertainties are incorporated. For evaluation, two approaches are suggested: one based on preference aggregation and the other based on socio-economics. Both implementations of the general framework are illustrated with simple but informative design examples to explore the basic features of the framework.\n\nThe first approach uses concepts similar to those found in multi-criteria decision theory, and directly combines reliability-based objectives with others. This approach is implemented in a single-stage design procedure. In the socio-economics based approach, a two-stage design procedure is recommended in which societal preferences are treated through reliability-based engineering performance measures, but emphasis is also given to economic objectives because these are especially important to the structural designer's client. A rational net asset value formulation including losses from uncertain future earthquakes is used to assess the economic performance of a design. A recently developed assembly-based vulnerability analysis is incorporated into the loss estimation.\n\nThe presented performance-based design framework allows investigation of various design issues and their impact on a structural design. It is a flexible one that readily allows incorporation of new methods and concepts in seismic hazard specification, structural analysis, and loss estimation.", "date": "2001-08-17", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2000.EERL-2000-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:2000.EERL-2000-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl2000-02.pdf", "url": "https://authors.library.caltech.edu/records/cmk2g-1pn29/files/eerl2000-02.pdf" }, "pub_year": "2001", "author_list": "Irfanoglu, Ayhan" }, { "id": "https://authors.library.caltech.edu/records/14ez8-44v35", "eprint_id": 26275, "eprint_status": "archive", "datestamp": "2023-08-19 01:36:54", "lastmod": "2024-01-13 05:29:39", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "May-Bennett-Scott", "name": { "family": "May", "given": "B. Scott" } } ] }, "title": "Probabilistic robust control: theory and applications", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 1998\n\nAccepted Version - eerl9708.pdf
", "abstract": "In this work, the development of a probabilistic approach to robust control is motivated by structural control applications in civil engineering. Often in civil structural applications, a system's performance is specified in terms of its reliability. In addition, the model and input uncertainty for the system may be described most appropriately using probabilistic or \"soft\" bounds on the model and input sets. The probabilistic robust control methodology contrasts with existing W... /A robust control methodologies that do not use probability information for the model and input uncertainty sets, yielding only the guaranteed (i.e., \"worst-case\") system performance, and no information about the system's probable performance which would be of interest to civil engineers.\n\nThe design objective for the probabilistic robust controller is to maximize the reliability of the uncertain structure/controller system for a probabilistically-described uncertain excitation. The robust performance is computed for a set of possible models by weighting the conditional performance probability for a particular model by the probability of that model, then integrating over the set of possible models. This integration is accomplished efficiently using an asymptotic approximation. The probable performance can be optimized numerically over the class of allowable controllers to find the optimal controller. Also, if structural response data becomes available from a controlled structure, its probable performance can easily be updated using Bayes's Theorem to update the probability distribution over the set of possible models. An updated optimal controller can then be produced, if desired, by following the original procedure. Thus, the probabilistic framework integrates system identification and robust control in a natural manner.\n\nThe probabilistic robust control methodology is applied to two systems in this thesis. The first is a high-fidelity computer model of a benchmark structural control laboratory experiment. For this application, uncertainty in the input model only is considered. The probabilistic control design minimizes the failure probability of the benchmark system while remaining robust with respect to the input model uncertainty. The performance of an optimal low-order controller compares favorably with higher-order controllers for the same benchmark system which are based on other approaches. The second application is to the Caltech Flexible Structure, which is a light-weight aluminum truss structure actuated by three voice coil actuators. A controller is designed to minimize the failure probability for a nominal model of this system. Furthermore, the method for updating the model-based performance calculation given new response data from the system is illustrated.", "date": "2001-08-17", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-08", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-08", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CMS-9503370" }, { "agency": "Earthquake Research Affiliates Program of Caltech" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "eerl9708.pdf", "url": "https://authors.library.caltech.edu/records/14ez8-44v35/files/eerl9708.pdf" }, "pub_year": "2001", "author_list": "May, B. Scott" }, { "id": "https://authors.library.caltech.edu/records/7srnq-cyn86", "eprint_id": 26277, "eprint_status": "archive", "datestamp": "2023-08-19 07:37:35", "lastmod": "2023-10-24 16:16:06", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Yunfeng", "name": { "family": "Zhang", "given": "Yunfeng" } } ] }, "title": "Semi-Active Control of Dynamically Excited Structures Using Active Interaction Control", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2001\n\nPublished - eerl2000-01.pdf
", "abstract": "This thesis presents a family of semi-active control algorithms termed Active Interaction Control (AIC) used for response control of dynamically excited structures. The AIC approach has been developed as a semi\ufdd3active means of protecting building structures against large earthquakes. The AIC algorithms include the Active Interface Damping (AID), Optimal Connection Strategy (OCS), and newly developed Tuned Interaction Damping (TID) algorithms. All of the AIC algorithms are founded upon the same basic instantaneous optimal control strategy that involves minimization of an energy\ufdd3based performance index at every time instant.\n\nA typical AIC system consists of a primary structure targeted for vibration control, a number of auxiliary structures, and interaction elements that connect the auxiliary structures to the primary structure. Through actively modulating the operating states of the interaction elements according to pre-specified control logic, control forces favorable to the control strategy are reactively developed within the interaction elements and the vibration of the primary structure is thus restrained. The merits of this structural control approach include both high control performance and minimal external power requirement for the operation of the control devices. The latter is important during large earthquakes when power blackouts are likely to occur. Most encouraging is that with currently available technology this control approach can be readily implemented in real structures.\n\nIn this thesis, the cause for an over\ufdd3attachment problem in the original OCS system is clarified and corresponding counter-measures are proposed. The OCS algorithm is reformulated within an energy framework and therefore all of the AIC control algorithms are unified under the same instantaneous optimal control strategy.\n\nTo implement the AIC algorithms into multi-degree-of-freedom systems, two approaches are formulated in this thesis: the Modal Control and Nodal Control approaches. The Modal Control approach directs the control effort to certain dominant response modes, and the Nodal Control approach directly controls the response quantities in physical space. It is found that the Modal Control approach is more efficient than the Nodal Control approach. The effectiveness of the AIC control algorithms is verified through numerical simulation results for three-story, nine-story and twenty-story steel-framed buildings. The statistical behavior of the AIC system is evaluated based on a Monte Carlo simulation.", "date": "2001-08-17", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2001.EERL-2001-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:2001.EERL-2001-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl2000-01.pdf", "url": "https://authors.library.caltech.edu/records/7srnq-cyn86/files/eerl2000-01.pdf" }, "pub_year": "2001", "author_list": "Zhang, Yunfeng" }, { "id": "https://authors.library.caltech.edu/records/zew36-35m20", "eprint_id": 26273, "eprint_status": "archive", "datestamp": "2023-08-19 01:24:12", "lastmod": "2023-10-24 16:15:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-J-F", "name": { "family": "Hall", "given": "John F." }, "orcid": "0000-0002-7863-5060" } ] }, "title": "Seismic response of steel frame buildings to near-source ground motions", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - eerl9705.pdf
", "abstract": "Strong near-source ground motions contain large, rapid displacement pulses that can have severe effects on structures. In the U.S. it is generally agreed that our design codes do not adequately address this kind of ground motion, and changes are being made to increase the design force levels, which will result in stronger buildings. In Japan, the design force levels for buildings have for some time been considerably greater than in the U.S. Even so, Japanese engineers are also concerned about the adequacy of their design provisions for strong near-source ground motions.\n\nThe issue of building strength appropriate for near-source ground motions is investigated in this report. Two different heights of buildings are selected, 6 stories and 20 stories, and for each height, designs of two different strengths are produced. The first design is according to the 1994 Uniform Building Code (1), and the second design follows current Japanese provisions (2). All four buildings are steel moment frames.\n\nOne important part of assessing near-source ground motions is to quantify the size of the region that is affected. An aspect of this is that near-source effects are directional and so are confined to only a portion of the near-fault zone. In this study, ground motions at a grid of sites sufficient to cover the region of near-source effects are employed. This is accomplished by using simulated ground motions. Three earthquake simulations are run: one based on the 1994 Northridge earthquake (Mw 6.7), another for the 1995 Kobe earthquake (Mw 6.9), and the third of a hypothetical Mw 7.0 earthquake on the Elysian Park fault in Los Angeles. In addition, various recorded motions from actual earthquakes, including Northridge and Kobe, are employed.\n\nPrevious studies of strong near-source ground motions have shown the potential for large story drifts in buildings and even collapse (3-7). Future design measures for near-source ground motions will likely have to consider all contributions to the strength of a building in order to be feasible. It follows from this that since future design methods will be based on assessment studies like the present one, the assessments should also be done as realistically as possible and include all important contributions to the strength of a structure. Such an approach is followed here. In addition, since strong near-source ground motions will likely produce severely nonlinear responses, it becomes necessary to include structural degradation effects. In this study, due to the common occurrence of welded connection failure in the Northridge and Kobe earthquakes and because this behavior would seem to be an important degradation mode, treatment of connection fracture is included. As there is now wide-spread interest in fracture of welded connections, this is an important part of the present investigation.\n\nThe Appendix contains a description of the computer program used for the analyses. Some of the notation used in this report is defined in this Appendix.", "date": "2001-08-10", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "eerl9705.pdf", "url": "https://authors.library.caltech.edu/records/zew36-35m20/files/eerl9705.pdf" }, "pub_year": "2001", "author_list": "Hall, John F." }, { "id": "https://authors.library.caltech.edu/records/pjg8m-5xa39", "eprint_id": 26259, "eprint_status": "archive", "datestamp": "2023-08-19 07:10:46", "lastmod": "2024-01-13 05:29:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Au-Siu-Kui", "name": { "family": "Au", "given": "Siu-Kui" } } ] }, "title": "On the solution of first excursion problems by simulation with applications to probabilistic seismic performance assessment", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2001", "abstract": "In a probabilistic assessment of the performance of structures subjected to uncertain environmental loads such as earthquakes, an important problem is to determine the probability that the structural response exceeds some specified limits within a given duration of interest. This problem is known as the first excursion problem, and it has been a challenging problem in the theory of stochastic dynamics and reliability analysis. In spite of the enormous amount of attention the problem has received, there is no procedure available for its general solution, especially for engineering problems of interest where the complexity of the system is large and the failure probability is small.\n\nThe application of simulation methods to solving the first excursion problem is investigated in this dissertation, with the objective of assessing the probabilistic performance of structures subjected to uncertain earthquake excitations modeled by stochastic processes. From a simulation perspective, the major difficulty in the first excursion problem comes from the large number of uncertain parameters often encountered in the stochastic description of the excitation. Existing simulation tools are examined, with special regard to their applicability in problems with a large number of uncertain parameters. Two efficient simulation methods are developed to solve the first excursion problem. The first method is developed specifically for linear dynamical systems, and it is found to be extremely efficient compared to existing techniques. The second method is more robust to the type of problem, and it is applicable to general dynamical systems. It is efficient for estimating small failure probabilities because the computational effort grows at a much slower rate with decreasing failure probability than standard Monte Carlo simulation. The simulation methods are applied to assess the probabilistic performance of structures subjected to uncertain earthquake excitation. Failure analysis is also carried out using the samples generated during simulation, which provide insight into the probable scenarios that will occur given that a structure fails.", "date": "2001-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2001.EERL-2001-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:2001.EERL-2001-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-2001-02.pdf", "url": "https://authors.library.caltech.edu/records/pjg8m-5xa39/files/EERL-2001-02.pdf" }, "pub_year": "2001", "author_list": "Au, Siu-Kui" }, { "id": "https://authors.library.caltech.edu/records/2xkn3-ddt64", "eprint_id": 26260, "eprint_status": "archive", "datestamp": "2023-08-19 05:14:19", "lastmod": "2024-01-13 05:29:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Au-Siu-Kui", "name": { "family": "Au", "given": "Siu-Kui" }, "orcid": "0000-0002-0228-1796" }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "On the solution of first-excursion failure problem for linear systems by efficient simulation", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - EERL-2000-01.pdf
", "abstract": "An analytical study of the failure region of the first-excursion reliability problem for linear dynamical systems subjected to Gaussian white noise excitation is carried out with a view to constructing a suitable importance sampling density for computing the first-excursion failure probability. Central to the study are 'elementary failure regions', which are defined as the failure region in the load space corresponding to the failure of a particular output response at a particular instant. Each elementary failure region is completely characterized by its design point, which can be computed readily using impulse response functions of the system. It is noted that the complexity of the first-excursion problem stems from the structure of the union of the elementary failure regions. One important consequence of this union structure is that, in addition to the global design point, a large number of neighboring design points are important in accounting for the failure probability. Using information from the analytical study, an importance sampling density is proposed. Numerical examples are presented, which demonstrate that the efficiency of using the proposed importance sampling density to calculate system reliability is remarkable.", "date": "2000-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:2000.EERL-2000-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:2000.EERL-2000-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-2000-01.pdf", "url": "https://authors.library.caltech.edu/records/2xkn3-ddt64/files/EERL-2000-01.pdf" }, "pub_year": "2000", "author_list": "Au, Siu-Kui and Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/0y8as-rfc63", "eprint_id": 26265, "eprint_status": "archive", "datestamp": "2023-08-19 04:13:27", "lastmod": "2024-01-13 05:29:37", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Carlson-Anders-Elof", "name": { "family": "Carlson", "given": "Anders E." } } ] }, "title": "Three-dimensional nonlinear inelastic analysis of steel moment-frame buildings damaged by earthquake excitations", "ispublished": "unpub", "full_text_status": "public", "note": "PhD., 1999\n\nAccepted Version - eerl9902.pdf
", "abstract": "The Northridge earthquake of January 17, 1994, highlighted the two previously known problems of premature fracturing of connections and the damaging capabilities of near-source ground motion pulses. Large ground motions had not been experienced in a city with tall steel moment-frame buildings before. Some steel buildings exhibited fracture of welded connections or other types of structural degradation.\n\nA sophisticated three-dimensional nonlinear inelastic program is developed that can accurately model many nonlinear properties commonly ignored or approximated in other programs. The program can assess and predict severely inelastic response of steel buildings due to strong ground motions, including collapse.\n\nThree-dimensional fiber and segment discretization of elements is presented in this work. This element and its two-dimensional counterpart are capable of modeling various geometric and material nonlinearities such as moment amplification, spread of plasticity and connection fracture. In addition to introducing a three-dimensional element discretization, this work presents three-dimensional constraints that limit the number of equations required to solve various three-dimensional problems consisting of intersecting planar frames.\n\nTwo buildings damaged in the Northridge earthquake are investigated to verify the ability of the program to match the level of response and the extent and location of damage measured. The program is used to predict response of larger near-source ground motions using the properties determined from the matched response.\n\nA third building is studied to assess three-dimensional effects on a realistic irregular building in the inelastic range of response considering earthquake directivity. Damage levels are observed to be significantly affected by directivity and torsional response.\n\nSeveral strong recorded ground motions clearly exceed code-based levels. Properly designed buildings can have drifts exceeding code specified levels due to these ground motions. The strongest ground motions caused collapse if fracture was included in the model. Near-source ground displacement pulses can cause columns to yield prior to weaker-designed beams. Damage in tall buildings correlates better with peak-to-peak displacements than with peak-to-peak accelerations.\n\nDynamic response of tall buildings shows that higher mode response can cause more damage than first mode response. Leaking of energy between modes in conjunction with damage can cause torsional behavior that is not anticipated.\n\nVarious response parameters are used for all three buildings to determine what correlations can be made for inelastic building response. Damage levels can be dramatically different based on the inelastic model used. Damage does not correlate well with several common response parameters.\n\nRealistic modeling of material properties and structural behavior is of great value for understanding the performance of tall buildings due to earthquake excitations.", "date": "1999-04-02", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1999.EERL-99-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1999.EERL-99-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl9902.pdf", "url": "https://authors.library.caltech.edu/records/0y8as-rfc63/files/eerl9902.pdf" }, "pub_year": "1999", "author_list": "Carlson, Anders E." }, { "id": "https://authors.library.caltech.edu/records/hfxpk-k7m48", "eprint_id": 26401, "eprint_status": "archive", "datestamp": "2023-08-19 03:53:49", "lastmod": "2024-01-13 05:30:52", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Halling-M-W", "name": { "family": "Halling", "given": "Marvin Wilford" } } ] }, "title": "Investigation of base-isolated structures during recent earthquakes and computer simulations utilizing near-source long-period ground motions", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1995\n\nAccepted Version - 9509.pdf
", "abstract": "The current study contains two major parts. Part One consists of the identification and analysis of three existing base-isolated buildings in Southern California. The identification and analysis utilize the recorded motions of these structures from past earthquakes. System identification is useful for understanding the extent to which the structures enter the nonlinear realm and how much their properties change.\n\nModels are constructed assuming completely elastic three-dimensional superstructures, with idealized bi-linear hysteretic elements for the isolating bearings. The properties used in the bearing models were taken from tests of the actual bearings before installation. The models were then verified by comparing their responses computed using the various recorded foundation ground motions, with the recorded responses of the actual structures. The models were adjusted to minimize the error of several response quantities.\n\nPart Two contains computer simulations subjecting a typical base-isolated building (TBIB) to two classes of ground motions. The first is a sampling of near-source recorded motion from past moderate-to-large earthquakes. The second is a group of synthetic near-source motions generated for a hypothetical M 7.0 earthquake. In some cases, the lateral response of the model exceeds the isolation gap, indicating that the displacement barrier would be impacted.\n\nIn order to further study base-isolated buildings when the isolation bearings undergo large displacements the (TBIB) model is used and the computer program 2D-BUMP is developed. This program includes the effects of a fully nonlinear superstructure, nonlinear springs acting as displacement barriers which engage at specified distances, and a tri-linear model for the elastomeric bearings. Using this model, several conclusions are drawn regarding the probable areal extent of damaging near-source ground motions from the M 7.0 event, as well as the behavior of base-isolated structures due to these near-source long-period ground motions.", "date": "1999-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1999.EERL-95-09", "official_url": "https://resolver.caltech.edu/CaltechEERL:1999.EERL-95-09", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9509.pdf", "url": "https://authors.library.caltech.edu/records/hfxpk-k7m48/files/9509.pdf" }, "pub_year": "1999", "author_list": "Halling, Marvin Wilford" }, { "id": "https://authors.library.caltech.edu/records/tqfe8-14d13", "eprint_id": 26313, "eprint_status": "archive", "datestamp": "2023-08-19 03:53:44", "lastmod": "2024-01-13 05:29:45", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Aagaard-B-T", "name": { "family": "Aagaard", "given": "Brad Thomas" } } ] }, "title": "Finite-element simulations of earthquakes", "ispublished": "unpub", "full_text_status": "public", "note": "Ph.D, 2000\n\nPublished - 9903.pdf
", "abstract": "This thesis discusses simulations of earthquake ground motions using prescribed ruptures and dynamic failure. Introducing sliding degrees of freedom led to an innovative technique for numerical modeling of earthquake sources. This technique allows efficient implementation of both prescribed ruptures and dynamic failure on an arbitrarily oriented fault surface. Off the fault surface the solution of the three-dimensional, dynamic elasticity equation uses well known finite-element techniques. We employ parallel processing to efficiently compute the ground motions in domains containing millions of degrees of freedom.\n\nUsing prescribed ruptures we study the sensitivity of long-period near-source ground motions to five earthquake source parameters for hypothetical events on a strike-slip fault (Mw 7.0 to 7.1) and a thrust fault (Mw 6.6 to 7.0). The directivity of the ruptures creates large displacement and velocity pulses in the ground motions in the forward direction. We found a good match between the severity of the shaking and the shape of the near-source factor from the 1997 Uniform Building Code for strike-slip faults and thrust faults with surface rupture. However, for blind thrust faults the peak displacement and velocities occur up-dip from the region with the peak near-source factor. We assert that a simple modification to the formulation of the near-source factor improves the match between the severity of the ground motion and the shape of the near-source factor.\n\nFor simulations with dynamic failure on a strike-slip fault or a thrust fault, we examine what constraints must be imposed on the coefficient of friction to produce realistic ruptures under the application of reasonable shear and normal stress distributions with depth. We found that variation of the coefficient of friction with the shear modulus and the depth produces realistic rupture behavior in both homogeneous and layered half-spaces. Furthermore, we observed a dependence of the rupture speed on the direction of propagation and fluctuations in the rupture speed and slip rate as the rupture encountered changes in the stress field. Including such behavior in prescribed ruptures would yield more realistic ground motions.", "date": "1999-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1999.EERL-99-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1999.EERL-99-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9903.pdf", "url": "https://authors.library.caltech.edu/records/tqfe8-14d13/files/9903.pdf" }, "pub_year": "1999", "author_list": "Aagaard, Brad Thomas" }, { "id": "https://authors.library.caltech.edu/records/d70g3-fxh69", "eprint_id": 26274, "eprint_status": "archive", "datestamp": "2023-08-19 02:23:02", "lastmod": "2023-10-24 16:16:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } }, { "id": "Toki-K", "name": { "family": "Toki", "given": "K." } } ] }, "title": "Proceedings of the U.S.-Japan Workshop on near-field earthquake damage in urban areas, Honolulu, Hawaii, January 5-7, 1998", "ispublished": "unpub", "full_text_status": "public", "abstract": "No abstract available.", "date": "1998-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1998.EERL-98-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1998.EERL-98-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl9801.pdf", "url": "https://authors.library.caltech.edu/records/d70g3-fxh69/files/eerl9801.pdf" }, "pub_year": "1998", "author_list": "Iwan, Wilfred D. and Toki, K." }, { "id": "https://authors.library.caltech.edu/records/49ec2-8nc41", "eprint_id": 26261, "eprint_status": "archive", "datestamp": "2023-08-19 02:22:57", "lastmod": "2024-01-13 05:29:34", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Papadimitriou-Costas", "name": { "family": "Papadimitriou", "given": "Costas" }, "orcid": "0000-0002-9792-0481" }, { "id": "Chan-Eduardo", "name": { "family": "Chan", "given": "Eduardo" } }, { "id": "Irfanoglu-Ayhan", "name": { "family": "Irfanoglu", "given": "Ayhan" }, "orcid": "0000-0001-8334-6717" } ] }, "title": "A performance-based optimal structural design methodology", "ispublished": "unpub", "full_text_status": "public", "abstract": "A general framework for multi-criteria optimal design is presented which is well-suited for performance-based design of structural systems operating in an uncertain dynamic environment. A decision theoretic approach is used which is based on aggregation of preference functions for the multiple, possibly conflicting, design criteria. This allows the designer to trade off these criteria in a controlled manner during the optimization. Reliability-based design criteria are used to maintain user-specified levels of structural safety by properly taking into account the uncertainties in the modeling and seismic loads that a structure may experience during its lifetime. Code-based requirements are also easily incorporated into this optimal design process. The methodology is demonstrated with two simple examples involving the design of a three-story steel-frame building for which the ground motion uncertainty is characterized by a probabilistic response spectrum which is developed from available attenuation formulas and seismic hazard models.", "date": "1998-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1998.EERL-97-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1998.EERL-97-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-97-03.pdf", "url": "https://authors.library.caltech.edu/records/49ec2-8nc41/files/EERL-97-03.pdf" }, "pub_year": "1998", "author_list": "Beck, James L.; Papadimitriou, Costas; et el." }, { "id": "https://authors.library.caltech.edu/records/csa73-tvv57", "eprint_id": 26333, "eprint_status": "archive", "datestamp": "2023-08-19 00:55:09", "lastmod": "2023-10-24 16:16:22", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-J-F", "name": { "family": "Hall", "given": "John F." }, "orcid": "0000-0002-7863-5060" } ] }, "title": "Efficient nonlinear seismic analysis of arch dams: User's manual for SCADA, Smeared Crack Arch Dam Analysis", "ispublished": "unpub", "full_text_status": "public", "note": "April 1996, modified July 1997", "abstract": "Linear earthquake analysis of a concrete arch dam, conducted either in the evaluation of an existing dam or in the design of a new one, typically shows large tensile stresses when the ground motion employed represents strong shaking. This result has spurred development of nonlinear analysis capabilities that attempt to model the opening and closing of contraction joints as well as cracks that are produced. Two recent computer programs (1a and lb, 2) both treat joints and cracks as zero-width zones of nonlinear springs connecting adjacent finite elements, but differ in detail.\n\nADAP-88 (la and lb) uses a multi-element discretization of solid elements through the thickness of the dam so as to be able to represent states of partial contact in the joints and cracks. Standard joint elements are used in the joint and crack planes. The program of reference 2 uses a single shell element discretization in the thickness direction with specially calibrated nonlinear rotational and axial springs to represent states of partial contact. The disadvantage of ADAP-88 is the relatively high computational effort required, while disadvantages of the formulation of reference 2 are some loss of accuracy and an inability to be generalized to include sliding in the joints and cracks. However, while sliding is straightforward conceptionally when using the standard joint elements such as employed in ADAP-88, including friction may lead to severe convergence difficulties.\n\nAt present, nonlinear analysis methods have not gained acceptance in the dam engineering community. Reliance is still based on the inadequate linear methods and ad hoc procedures to assess the high tensile stresses that are computed. Part of the problem is the difficulty of validating the nonlinear analysis capabilities. Some progress is being made, however, by different researchers taking different approaches of nonlinear analysis and then comparing results. In this spirit and also with the goal of developing a practical nonlinear analysis technique that attempts to reach a compromise between computational effort and model complexity, while still giving useful results, this simplified nonlinear earthquake analysis procedure for concrete arch dams is offered together with fully documented computer program.\n\nThe procedure is based on the \"smeared\" approach to model joints and cracks whereby the contact nonlinearities are incorporated through conditions placed on the stresses at the\nintegration points of the (shell) finite elements of the dam. This approach sacrifices some accuracy for computational efficiency. The faster computation comes about by a reduction in the number of degrees of freedom and an improvement in convergence even to the point of being able to handle frictional sliding. A typical computer run for an earthquake analysis of an arch dam to strong ground motion takes about one hour on a DEC 3000 Model 400 computer with a 100 MEPS processor. This efficiency allows parameter studies to be undertaken which are an essential part of any evaluation process.\n\nAs with the linear analysis methods, engineering judgment is still a necessary and important element. However, it is hoped that the gap between mathematical model and real-world situation is reduced enough with the offered program so that the engineer can now be confident in spanning between them.", "date": "1997-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-96-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-96-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "9601.pdf", "url": "https://authors.library.caltech.edu/records/csa73-tvv57/files/9601.pdf" }, "pub_year": "1997", "author_list": "Hall, John F." }, { "id": "https://authors.library.caltech.edu/records/7tjsh-01n15", "eprint_id": 26402, "eprint_status": "archive", "datestamp": "2023-08-19 00:55:13", "lastmod": "2023-10-24 16:18:21", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-L-J", "name": { "family": "Wang", "given": "Luo-Jia" } } ] }, "title": "Active interaction control for civil structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1997\n\nPublished - 9704.pdf
", "abstract": "This thesis presents a civil engineering approach to active control for civil structures. The proposed control technique, termed Active Interaction Control (AIC), utilizes dynamic interactions between different structures, or components of the same structure, to reduce the resonance response of the controlled or primary structure under earthquake excitations. The primary control objective of AIC is to minimize the maximum story drift of the primary structure. This is accomplished by timing the controlled interactions so as to withdraw the maximum possible vibrational energy from the primary structure to an auxiliary structure, where the energy is stored and eventually dissipated as the external excitation decreases. One of the important advantages of AIC over most conventional active control approaches is the very low external power required.\n\nIn this thesis, the AIC concept is introduced and a new AIC algorithm, termed Optimal Connection Strategy (OCS) algorithm, is proposed. The efficiency of the OCS algorithm is demonstrated and compared with two previously existing AIC algorithms, the Active Interface Damping (AID) and Active Variable Stiffness (AVS) algorithms, through idealized examples and numerical simulations of Single- and Multi-Degree-of Freedom systems under earthquake excitations. It is found that the OCS algorithm is capable of significantly reducing the story drift response of the primary structure. The effects of the mass, damping, and stiffness of the auxiliary structure on the system performance are investigated in parametric studies. Practical issues such as the sampling interval and time delay are also examined. A simple but effective predictive time delay compensation scheme is developed.", "date": "1997-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "9704.pdf", "url": "https://authors.library.caltech.edu/records/7tjsh-01n15/files/9704.pdf" }, "pub_year": "1997", "author_list": "Wang, Luo-Jia" }, { "id": "https://authors.library.caltech.edu/records/5aga2-x7r63", "eprint_id": 26247, "eprint_status": "archive", "datestamp": "2023-08-19 00:54:52", "lastmod": "2023-10-24 16:15:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Polidori-D-C", "name": { "family": "Polidori", "given": "David C." } } ] }, "title": "A probabilistic treatment of uncertainty in nonlinear dynamical systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD., 1998\n\nPublished - eerl9709.pdf
", "abstract": "In this work, computationally efficient approximate methods are developed for analyzing uncertain dynamical systems. Uncertainties in both the excitation and the modeling are considered and examples are presented illustrating the accuracy of the proposed approximations.\n\nFor nonlinear systems under uncertain excitation, methods are developed to approximate the stationary probability density function and statistical quantities of interest. The methods are based on approximating solutions to the Fokker-Planck equation for the system and differ from traditional methods in which approximate solutions to stochastic differential equations are found. The new methods require little computational effort and examples are presented for which the accuracy of the proposed approximations compare favorably to results obtained by existing methods. The most significant improvements are made in approximating quantities related to the extreme values of the response, such as expected outcrossing rates, which are crucial for evaluating the reliability of the system.\n\nLaplace's method of asymptotic approximation is applied to approximate the probability integrals which arise when analyzing systems with modeling uncertainty. The asymptotic approximation reduces the problem of evaluating a multidimensional integral to solving a minimization problem and the results become asymptotically exact as the uncertainty in the modeling goes to zero. The method is found to provide good approximations for the moments and outcrossing rates for systems with uncertain parameters under stochastic excitation, even when there is a large amount of uncertainty in the parameters. The method is also applied to classical reliability integrals, providing approximations in both the transformed (independently, normally distributed) variables and the original variables. In the transformed variables, the asymptotic approximation yields a very simple formula for approximating the value of SORM integrals. In many cases, it may be computationally expensive to transform the variables, and an approximation is also developed in the original variables. Examples are presented illustrating the accuracy of the approximations and results are compared with existing approximations.", "date": "1997-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-09", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-09", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "eerl9709.pdf", "url": "https://authors.library.caltech.edu/records/5aga2-x7r63/files/eerl9709.pdf" }, "pub_year": "1997", "author_list": "Polidori, David C." }, { "id": "https://authors.library.caltech.edu/records/kws90-7r323", "eprint_id": 26276, "eprint_status": "archive", "datestamp": "2023-08-19 00:55:03", "lastmod": "2023-10-24 16:16:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vanik-M-W", "name": { "family": "Vanik", "given": "Michael W." } } ] }, "title": "A Bayesian probabilistic approach to structural health monitoring", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1997\n\nPublished - eerl9707.pdf
", "abstract": "A Bayesian probabilistic methodology for on-line structural health monitoring which addresses the issue of parameter uncertainty inherent in problem is presented. The method uses modal parameters for a limited number of modes identified from measurements taken at a restricted number of degrees of freedom of a structure as the measured structural data. The application presented uses a linear structural model whose stiffness matrix is parameterized to develop a class of possible models. Within the Bayesian framework, a joint probability density function (PDF) for the model stiffness parameters given the measured modal data is determined. Using this PDF, the marginal PDF of the stiffness parameter for each substructure given the data can be calculated.\n\nMonitoring the health of a structure using these marginal PDFs involves two steps. First, the marginal PDF for each model parameter given modal data from the undamaged structure is found. The structure is then periodically monitored and updated marginal PDFs are determined. A measure of the difference between the calibrated and current marginal PDFs is used as a means to characterize the health of the structure. A procedure for interpreting the measure for use by an expert system in on-line monitoring is also introduced.\n\nThe probabilistic framework is developed in order to address the model parameter uncertainty issue inherent in the health monitoring problem. To illustrate this issue, consider a very simplified deterministic structural health monitoring method. In such an approach, the model parameters which minimize an error measure between the measured and model modal values would be used as the \"best\" model of the structure. Changes between the model parameters identified using modal data from the undamaged structure and subsequent modal data would be used to find the existence, location and degree of damage. Due to measurement noise, limited modal information, and model error, the \"best\" model parameters might vary from one modal dataset to the next without any damage present in the structure. Thus, difficulties would arise in separating normal variations in the identified model parameters based on limitations of the identification method and variations due to true change in the structure. The Bayesian framework described in this work provides a means to handle this parametric uncertainty.\n\nThe probabilistic health monitoring method is applied to simulated data and laboratory data. The results of these tests are presented.", "date": "1997-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl9707.pdf", "url": "https://authors.library.caltech.edu/records/kws90-7r323/files/eerl9707.pdf" }, "pub_year": "1997", "author_list": "Vanik, Michael W." }, { "id": "https://authors.library.caltech.edu/records/9haaf-70d72", "eprint_id": 26262, "eprint_status": "archive", "datestamp": "2023-08-19 00:54:58", "lastmod": "2023-10-24 16:15:47", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Earthquake response of tall regular buildings", "ispublished": "unpub", "full_text_status": "public", "abstract": "No abstract available.", "date": "1997-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1997.EERL-97-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1997.EERL-97-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-97-01.pdf", "url": "https://authors.library.caltech.edu/records/9haaf-70d72/files/EERL-97-01.pdf" }, "pub_year": "1997", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/yvzvk-f1689", "eprint_id": 26328, "eprint_status": "archive", "datestamp": "2023-08-20 07:05:54", "lastmod": "2023-10-24 16:16:18", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Chi-Ming", "name": { "family": "Yang", "given": "Chi-Ming" } } ] }, "title": "Statistical system identification and applications to seismic response of structures", "ispublished": "unpub", "full_text_status": "public", "abstract": "A pragmatic and versatile statistical system identification framework is presented and applied to seismic response records of structures. The framework is based on the interpretation of probability as a measure of plausibility and on Bayesian statistical inference. Various classical system identification techniques can be derived and viewed as the special cases of the framework. However, the framework can provide a more informative interpretation of the identified optimal model.\n\nWhen the number of sampled input and output data from structures is large, useful asymptotic approximations of the analytical results are available. These asymptotic approximations are incorporated into the framework by introducing the definitions of system identifiability and model identifiability. New asymptotic approximation results are derived for the system un-identifiable case.\n\nFrom the viewpoint of asymptotic approximations, the system identification problem is a non-trivial global optimization problem. Two generalized trajectory methods, the homotopy scheme and the relaxation scheme, are presented which can be combined to provide a very robust numerical procedure for global optimization. Both methods can also be applied to find the roots of a set of nonlinear algebraic equations.\n\nStructural model updating is useful because it can be applied to structural health monitoring and is also desirable since the theoretically based stiffness matrix of a structure can be improved by using the measured structural response data. However, no well-accepted solution to this difficult problem has emerged primarily because it is an ill-conditioned and non-unique inverse problem. A single-stage structural model updating approach using the least-squares prediction-error system identification method and a substructuring technique is proposed and applied to simulated and real structural response data.", "date": "1996-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1996.EERL-96-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1996.EERL-96-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9602.pdf", "url": "https://authors.library.caltech.edu/records/yvzvk-f1689/files/9602.pdf" }, "pub_year": "1996", "author_list": "Yang, Chi-Ming" }, { "id": "https://authors.library.caltech.edu/records/72grz-zrp91", "eprint_id": 26335, "eprint_status": "archive", "datestamp": "2023-08-20 07:06:02", "lastmod": "2023-10-24 16:16:26", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-L-J", "name": { "family": "Wang", "given": "Luo-Jia" } }, { "id": "Gu-Q", "name": { "family": "Gu", "given": "Qun" } }, { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "A Collection of processed near-field earthquake accelerograms with response and drift spectra", "ispublished": "unpub", "full_text_status": "public", "abstract": "A number of particularly important earthquake accelerograms were measured by instruments that were located in the Near-Field region of several recent earthquakes. For a strike-slip or a thrust fault earthquake, this region is taken to be the area within and immediately adjacent to the surface trace or the surface prediction of the fault rupture plane and its extension to the earth's surface. Such accelerograms are termed near-field earthquake accelerograms. They possess the following features that differ from other earthquake accelerograms:\n\n\u2003 distinctive pulse-like time histories,\n\n\u2003 high peak velocities, and\n\n\u2003 high ground displacements.\n\nThese features of nm-field ground motion have not yet been well documented and are generally not considered in seismic design. It has been shown, however, that they can place very serious demand on structures located in the near-field region of an earthquake [I].\n\nThis report presents uniformly processed data for 12 near-field earthquake accelerograms obtained from four recent earthquakes. The results are presented in the following format:\n\ntime histories of acceleration, velocity, and displacement rotated to east-west, north-south, and maximum velocity directions,\n\nhorizontal particle trajectories,\n\nResponse Spectra for the east-west, north-south, and maximum velocity directions, and\n\nDrift Demand Spectra for the east-west, north-south, and maximum velocity directions.\n\nTables 1-4 summarize the relevant information for the earthquakes and near-field accelerograms in this report. Plots of time histories, horizontal particle trajectories, Response Spectra and Drift Demand Spectra are presented in the figures following Table 4.\n\nAll accelerograms were uniformly corrected using the processing scheme developed by Iwan and Chen [2]. This includes appropriate instrument correction according to the instrument type and baseline correction without band-pass filtering.\n\nThe time history, Response Spectrum and Drift Demand Spectrum for the north-south component of the El Centro (ELC) accelerogram obtained in the 1940 Imperial Valley earthquake are included in Appendix I for purposes of comparison. As shown by their response and Drift Demand Spectra, all 12 earthquake accelerograms featured in this report place much higher demands on the response and interstory drift of structures than does the standard ELC ground motion. This suggests that the widely used ELC accelerogram may be inadequate for some design purposes.\n\nAll data processing, response and Drift Demand Spectral computations, and plotting were performed using a Matlab-based package [4]", "date": "1996-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1996.EERL-96-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1996.EERL-96-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9605.pdf", "url": "https://authors.library.caltech.edu/records/72grz-zrp91/files/9605.pdf" }, "pub_year": "1996", "author_list": "Wang, Luo-Jia; Gu, Qun; et el." }, { "id": "https://authors.library.caltech.edu/records/e0wfb-mfb25", "eprint_id": 26334, "eprint_status": "archive", "datestamp": "2023-08-20 07:05:58", "lastmod": "2023-10-24 16:16:24", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-L-J", "name": { "family": "Wang", "given": "Luo-Jia" } } ] }, "title": "Processing of near-field earthquake accelerograms", "ispublished": "unpub", "full_text_status": "public", "abstract": "The Near-Field pulse-like velocity and displacement time histories associated with a strong earthquake can greatly affect a wide range of different types of structures [I]. The important long period components in NEAR-FIELD earthquake accelerograms, however, are normally eliminated or distorted by conventional data processing which is based on band-pass filtering; for example, using an Ormsby filter with a low frequency cut-off of 0.2-0.4 Hz.\n\nA new data processing technique has been proposed by Iwan and Chen [2] to recover the long period components from NEAR-FIELD earthquake accelerograms. This technique is based on the inverse of the data recording and retrieving procedure, which includes appropriate instrument correction according to the instrument type, and baseline correction without band-pass filtering. It may be briefly summarized by the following steps:\n\nI .Apply a least-mean-square linear fit to the uncorrected accelerograms to eliminate any uncertainty in the instrument centering.\n\n2.Apply instrument correction to compensate for the fact that the transfer function of the transducer is not flat over the entire frequency band.\n\n3.Integrate the instrument corrected acceleration time history to obtain a raw velocity time history, assuming zero initial velocity. A trapezoidal integration rule and a central difference differentiation scheme are used herein.\n\n4.Apply a segmented polynomial baseline fit to the raw velocity time history to remove any non-physical trends. Since the ground velocity physically begins at zero and ends at zero, the baseline is fitted to the initial and final portions of the raw velocity time history. These two polynomials are connected by the lowest order (smoothest) polynomial baseline connection that continuously connects the initial and final portions of the accelerogram. The objective of baseline correction is to diminish the long-period noise or drift introduced in the signal recording and playback process.\n\n5.Integrate the baseline corrected velocity time history to obtain a displacement time history, assuming zero initial displacement. Differentiate the baseline corrected velocity time history to obtain the corrected acceleration time history.\n\nA Matlab package has been written to fulfill this data processing procedure. The package is also able to plot acceleration, velocity, and displacement time histories, to plot horizontal displacement particle trajectories, and to compute and plot Response Spectra and Drift Demand Spectra [3]. There are a total of 15 Matlab routines (functions) in this package. Sample Matlab programs are contained in Appendix 1. SAMPLELM and SAMPLE2.M demonstrate the usage of the routines. Appendix 2 lists all routines. A floppy disk containing all routines is included with this report.", "date": "1996-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1996.EERL-96-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1996.EERL-96-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9604.pdf", "url": "https://authors.library.caltech.edu/records/e0wfb-mfb25/files/9604.pdf" }, "pub_year": "1996", "author_list": "Wang, Luo-Jia" }, { "id": "https://authors.library.caltech.edu/records/jqazq-bk791", "eprint_id": 26272, "eprint_status": "archive", "datestamp": "2023-08-20 05:22:29", "lastmod": "2023-10-24 16:15:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-J-F", "name": { "family": "Hall", "given": "John F." }, "orcid": "0000-0002-7863-5060" } ] }, "title": "Parameter study of the response of moment-resisting steel frame buildings to near-source ground motions", "ispublished": "unpub", "full_text_status": "public", "abstract": "A parameter study is performed to investigate the effects of strong near-source ground motions from moderate-size earthquakes (Mw=7) on moment-resisting steel frame buildings. Two buildings, one 6 stories and the other 20 stories, are subjected to the Olive View Hospital free-field record from the Northridge earthquake and other ground motions from three earthquake simulations (Northridge earthquake, a hypothetical Mw7.1 Elysian Park blind-thrust earthquake, and another blind-thrust earthquake of Mw7.0). Parameters examined for the buildings include material yielding, weld fracture, presence of slab, accumulation of damage from a second earthquake, and vertical ground motion. \n A significant fraction of the ground motions cause excessive amounts of deformations in the buildings, especially the 6-story one, even for the case where all welds are assumed to be perfect. These ground motions exceed the earthquake representation in the code, and, since they appear to be reasonable motions that should be considered in design, the implication is that the code design force levels need to be raised for locations in near-fault regions. Including weld fracture increases the displacements of the building and the potential for severe damage or collapse from column failure or excessive lateral sway. The buildings collapsed in several of the analyses. Including the floor slab increased the amount of column yielding and did not improve the behavior. A second earthquake such as a strong aftershock or subsequent main shock is a concern, especially if many welds are cracked from the initial event. However, a limited study of vertical ground motion showed it to be of minor importance. Strongly nonlinear building behavior is sensitive to many assumptions about features which are poorly understood, both structure and ground motion, and so the results need to be carefully interpreted.", "date": "1995-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-08", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-08", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl9508.pdf", "url": "https://authors.library.caltech.edu/records/jqazq-bk791/files/eerl9508.pdf" }, "pub_year": "1995", "author_list": "Hall, John F." }, { "id": "https://authors.library.caltech.edu/records/3k2vc-t6v23", "eprint_id": 26263, "eprint_status": "archive", "datestamp": "2023-08-20 05:22:24", "lastmod": "2023-10-24 16:15:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "Drift demand spectra for selected Northridge sites", "ispublished": "unpub", "full_text_status": "public", "abstract": "This report presents uniformly processed data for ground motion at selected near-field sites where high peak velocities were observed during the Northridge earthquake. These data are used to produce drift demand spectra. Drift spectra are also presented for artificially generated Northridge ground motions. The results of the drift demand spectra are compared with results of numerical response evaluations of actual and prototype buildings.", "date": "1995-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "EERL-95-07.pdf", "url": "https://authors.library.caltech.edu/records/3k2vc-t6v23/files/EERL-95-07.pdf" }, "pub_year": "1995", "author_list": "Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/zysmv-2h644", "eprint_id": 26400, "eprint_status": "archive", "datestamp": "2023-08-20 05:22:33", "lastmod": "2024-01-13 05:30:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Papadimitriou-Costas", "name": { "family": "Papadimitriou", "given": "Costas" }, "orcid": "0000-0002-9792-0481" }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } }, { "id": "Katafygiotis-L-S", "name": { "family": "Katafygiotis", "given": "Lambros S." } } ] }, "title": "Asymptotic expansions for reliabilities and moments of uncertain dynamic systems", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - 9505.pdf
", "abstract": "An asymptotic approximation is developed for evaluating the probability integrals which arise in the determination of the reliability and response moments of uncertain dynamic systems subject to stochastic excitation. The method is applicable when the probabilities of failure or response moments conditional on the system parameters are available, and the effect of the uncertainty in the system parameters is to be investigated. In particular, a simple analytical formula for the probability of failure of the system is derived and compared to some existing approximations, including an asymptotic approximation based on SORM methods. Simple analytical formulas are also derived for the sensitivity of the failure probability and response moments to variations in parameters of interest. Conditions for which the proposed asymptotic expansion is expected to be accurate are presented. Since numerical integration is only computationally feasible for investigating the accuracy of the proposed method for a small number of uncertain system parameters, simulation techniques are also used. A simple importance sampling method is shown to converge much more rapidly than straightforward Monte-Carlo simluation. Simple structures subjected to white noise stochastic excitation axe used to illustrate the accuracy of the proposed analytical approximation. Results from the computationally efficient perturbation method are also included for comparison. The results show that the asymptotic method gives acceptable approximations, even for systems with relatively large uncertainty, and in most cases, it outperforms the perturbation method.", "date": "1995-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1995.EERL-95-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1995.EERL-95-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9505.pdf", "url": "https://authors.library.caltech.edu/records/zysmv-2h644/files/9505.pdf" }, "pub_year": "1995", "author_list": "Papadimitriou, Costas; Beck, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/h19sf-w8c96", "eprint_id": 26396, "eprint_status": "archive", "datestamp": "2023-08-20 03:49:44", "lastmod": "2023-10-24 16:18:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pich-P", "name": { "family": "Pich", "given": "Peter" } } ] }, "title": "Nonlinear rigid block dynamics", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1995", "abstract": "Motion of a block on flat ground under the influence of gravity is studied.\n\nA general model is introduced for the free motion of a rectangular, rigid block on a continuous, perfectly elastic foundation. The model includes friction forces between the block and foundation and allows for sliding, rocking and flight of the block. Solutions are obtained through numerical integration. A three parameter study is carried out, namely as a function of aspect ratio, r, coefficient of friction, \u00ec, and non-dimensional stiffness, k_, for various initial conditions.\n\nDominant types of response are identified and the stability of the block again overturning and its tendency to fly are studied. For initial conditions with sufficient energy, critical curves are found in the (k-, r) parameter space which define a transition between a flight and no flight region. For initial conditions with sufficient energy there also exists a critical curve in the same parameter space which separates a region of overturning from a region where the block does not overturn.\n\nChaos is found in the flight region of the (k_, r) parameter space for sufficiently high r. Poincare maps and Liapunov exponents are computed to document the existence of chaos.", "date": "1994-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1994.EERL-95-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1994.EERL-95-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9501.pdf", "url": "https://authors.library.caltech.edu/records/h19sf-w8c96/files/9501.pdf" }, "pub_year": "1994", "author_list": "Pich, Peter" }, { "id": "https://authors.library.caltech.edu/records/mcg0p-15a85", "eprint_id": 26438, "eprint_status": "archive", "datestamp": "2023-08-20 00:58:05", "lastmod": "2024-01-13 05:31:17", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Challa-Venkata-Ramana-Murty", "name": { "family": "Challa", "given": "Venkata Ramana Murty" } } ] }, "title": "Nonlinear seismic behaviour of steel planar moment-resisting frames", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1992\n\nAccepted Version - 9201.pdf
", "abstract": "The nonlinear response of steel planar moment-resisting frames during strong earthquakes poses a strong need for accurately modelling inelastic behaviour and large displacements. This thesis attempts to provide realistic and efficient analytical tools to aid this study.\n\nTwo large -displacement small-strain beam-column models are employed to include material and geometric nonlinearities. The first model assumes lumped plasticity, and discretises an element into segments. Axial force-Bending Moment strength interaction and flexural bowing are considered. Ten characteristic segment states are identified. An efficient numerical scheme is suggested to solve the nonlinear governing equations. This model only approximately represents the strength and stiffness of beam-columns.\n\nA comprehensive finite element beam-column model is developed to more accurately model the strength and stiffness. A beam-column is discretised into segments, and further, each segment into one-dimensional fibres. A uniaxial cyclic constitutive law valid under arbitrary transient loading is proposed for structural steel. This physically motivated law incorporates the initial yield plateau, and provides explicit expressions for stress in terms of strain throughout the hysteretic path. This law is used to control the hysteretic loading of fibres.\n\nA simple semi-empirical model is employed to analytically describe the highly nonlinear hysteretic behaviour of flexible joint panel zones in steel planar frames. Some modelling assumptions that may be made in frame analyses are evaluated. Numerical study of a building frame with flexible joints indicates that its collapse is sensitive to the joint panel zone design in addition to the ground motion.", "date": "1992-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1992.EERL-92-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1992.EERL-92-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9201.pdf", "url": "https://authors.library.caltech.edu/records/mcg0p-15a85/files/9201.pdf" }, "pub_year": "1992", "author_list": "Challa, Venkata Ramana Murty" }, { "id": "https://authors.library.caltech.edu/records/rd01b-60w93", "eprint_id": 26530, "eprint_status": "archive", "datestamp": "2023-08-20 00:58:11", "lastmod": "2023-10-24 16:22:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "Proceedings of the International Workshop on Seismic Design and Reassessment of Offshore Structures", "ispublished": "unpub", "full_text_status": "public", "abstract": "This Executive Summary presents the major conclusions and recommendations of the International Workshop on Seismic Design and Reassessment of Offshore Structures. Full versions of the text of all invited lecturers and complete working group reports are contained elsewhere in these Proceedings.\n\nSite Seismic Hazard and Ground Motion\n\nContinuous improvements have been made in the state-of-the-art of estimation of seismic ground motion for design and reassessment of offshore platforms. C. B. Crouse of Dames & Moore provides an overview of methods used to determine seismic design parameters for offshore structures. A site\ufdd3specific analysis is generally performed to develop seismic design parameters for a particular site. The first step is to define the seismic sources in the site region, and develop a model of the attenuation of ground motion that is appropriate for the region. Next, probabilistic and/or deterministic analyses are performed to estimate the ground motion parameters. For new designs, both approaches are commonly used. For reassessment and requalification, a probabilistic approach is generally preferred. There are three basic inputs needed for a probabilistic approach; 1) identification of earthquake sources in the site region, 2) definition of the earthquake recurrence for each source, and 3) definition of the attenuation of earthquake ground motion, usually expressed as a function of distance from the source and earthquake magnitude.\n\nAn example is given of a typical offshore platform located in a subduction zone environment. This example is used to illustrate some of the more important issues in the determination of seismic parameters. These issues include: extrapolation from available data to larger design level events, inclusion of basin effects on soil amplification, the relationship between vertical and horizontal earthquake motions, and the effect of the water column on vertical acceleration.\n\nIt is concluded that estimation of ground motion for offshore structural design and reassessment is a challenging process involving several technical disciplines including seismology, geology, geotechnical and structural engineering, as well as political considerations. Unfortunately, many uncertainties still exist in the specification of seismic design parameters based on site-specific seismic hazard analyses.\n\nThe Working Group on Site Seismic Hazard and Ground Motion, co\ufdd3chaired by Allin Cornell of Stanford University and Paul Somerville of Woodward Clyde Consultants, makes the following major conclusions and recommendations:\n\n1. There is a critical need for more recorded earthquake seafloor motion data in regions where offshore facilities are proposed or currently constructed.\n\n2. There is a need for the application of the latest state-of-the-art techniques in the prediction of ground motion, especially in the period range of 1-4 seconds.\n\n3. Further research should be undertaken related to defining the subsurface input reference point for strong ground motion.\n\n4. Deep geophysical data is needed to better characterize offshore seismic sources.\n\nDesign, Reassessment And Requalification\n\nRobert Bea of the University of California observes that the primary objectives of a seismic design methodology are to assure that a new offshore structure will have sufficient strength and ductility to satisfy its intended purposes without undue expense or risk. He argues that the primary focus of the platform designer should be on the response that develops after first significant yielding occurs in the structural elements and components that comprise the structural system of the platform, and the damage states that can lead to collapse of the platform. In the design criteria, member resistance and factors should be chosen to provide acceptable reliability against significant damage or collapse. A strength level earthquake is not anticipated to induce significant damage or inelastic response in the structural elements.\n\nStatic push-over analyses have been used extensively to demonstrate the capacity and ductility of offshore platforms. The margin of safety beyond the elastic performance requirement is often expressed by a platform Reserve Strength Ratio (RSR) which is the ratio of the maximum lateral load capacity of the platform to a reference load induced by the strength level earthquake. Bea has found that platforms designed according to current American Petroleum Institute (API) guidelines generally have an RSR 2.\n\nIn contrast to a seismic design methodology, a seismic requalification methodology should provide a set of processes and parameters to insure that an existing platform will be able to develop acceptable performance during its proposed service period. Bea summarizes his \"comprehensive\" seismic requalification methodology. In this methodology, the judgment of fitness for purpose is based on the total probability of failure of the platform system, including topside equipment and operations, the potential costs, and the consequences associated with failure. If a platform is judged not fit-for-purpose, guidance is provided as to how to improve its performance characteristics.\n\nTwo different approaches may be used to define the fitness-for-purpose criteria in this methodology: \"utility optimization\" or \"standard of practice.\" The utility optimization approach is based on an evaluation of the positive and negative utilities associated with different risks. Utility may be measured in a variety of ways. Costs and benefits are commonly measured in monetary terms. The objective is usually expressed in terms of minimization of total expected cost.\n\nThe standard-of-practice approach is based on current design and requalification decisions which have been made for other platforms. The underlying premise of this approach is that, over time, the profession, industry, and regulatory agencies have defined acceptable combinations of probabilities of failure and consequences associated with failure. In the standard-of-practice approach, the decision on whether a structure is fit-for-purpose is based upon its probability of failure and total cost of failure as compared to other new and existing platforms. Straight line \"acceptable\" and \"marginal\" boundaries have been proposed in a log-log total probability vs. total cost space.\n\nBea expresses the opinion that none of the available seismic requalification methodologies are as highly developed as seismic design methodologies. It is argued that the industry has the necessary technology to develop definitive engineering guidelines from the available requalification methodologies and that high priority should be given to developing such guidelines. It is further asserted that generally accepted fitness-for-purpose criteria that are dependent on consequences and likelihoods of failure need to be developed for both new and existing offshore structures.\n\nDavid Wisch of Texaco Corporation presents the results of a 1992 API requalification project. A panel, consisting of Wilfred Iwan (Chairman), Allin Cornell, George Housner and Charles Thiel, was constituted by the API to recommend an approach to seismic requalification of offshore structures. The API Panel's strategy is based on the establishment of separate acceptable levels of risk for life safety and environmental hazards. The Panel reasoned that life safety and environment hazards are essentially different in character and need not, indeed cannot, be measured by a common scale such as dollars. The Panel's acceptable risk for life safety is based on the concept that the risk to a worker on an offshore platform should be comparable to that for a worker in a similar facility onshore. This was believed to be a publicly acceptable level of risk. Acceptable environmental risk is based upon the risk of spills that occur from other sources in the same region which are deemed publicly acceptable. The Panel uncovered no safety or environmental issues associated with the seismic safety reassessment process that indicated platforms should be subject to risk criteria more restrictive than those for land-based industrial facilities.\n\nThe Panel argued that the focus of seismic safety reassessment should be on limiting, to an acceptable level, the risk due to catastrophic impacts of earthquakes, where a catastrophic impact is defined as one that has unacceptable large life and/or environmental safety consequences. It was further argued that offshore facilities should have more rigorous site hazard and engineering behavior analysis than onshore facilities in order to achieve these goals, even though they have comparable quantitative risk limits. The Panel recommend that decisions related to cost and economic return be left to platform owners and not be included in reassessment or requalification requirements imposed by regulatory agencies.\n\nThe Panel concluded that use of the design and analysis guidelines presented in the API recommended practice document, RP 2A, 19th edition, will produce a structure with life safety comparable to that of well-engineered structures onshore provided that: 1) the hazard study and structural analyses are peer reviewed, 2) the seismic hazards are determined in accordance with strength and ductility level earthquakes with 200 and 1,000 year return periods, respectively, 3) a ductility level earthquake analysis is always performed, and 4) proper allowance is made for lifesafety risks associated with platform appurtenances.\n\nFor structures which do not meet the guidelines of RP 2A, the Panel determined that an objective of an annual probability of failure (collapse) of less than 1 x 10 -3 would be consistent with providing a level of life safety comparable to that of onshore structures. The Panel also concluded that median value results from hazard analyses should be used in any probabilistic analyses to verify satisfaction of this objective. For Southern California waters, the Panel recommended an environmental performance objective of a release of no more than 2,000 barrels from any possible source including wells, pipelines, and onboard storage.\n\nWisch notes that the API Panel study is only one of a series of steps being undertaken by the offshore industry. Some of the questions that are being and will be answered by these studies include: 1) whether platforms can be categorized as to their expected response based on type or age, 2) whether an effective screening procedure can be developed to avoid detailed case-by-case assessment of offshore structures, 3) how independent review and peer review should best be incorporated into the reassessment process, 4) the different issues that must be addressed in reassessment outside the U.S., and 5) how acceptability criteria should relate to recommended industry practice, codes, regulatory requirements, and economic considerations.\n\nThe Working Group on Design, Reassessment and Requalification, co-chaired by Kris Digre of Shell Oil Co. and William Ibbs of U.C. Berkeley, arrives at the following conclusions and recommendations:\n\n1. The strength level and ductility level earthquakes employed in current API recommended practice need to be more precisely specified; perhaps tied to some other criteria.\n\n2. A ductility level analysis should always be required.\n\n3. Accelerographs should be installed in all offshore structures for the purpose of acquiring data on structural performance during actual earthquake excitation.\n\n4. Technology should be further developed and shared regarding the following: joint and member capacities (including in-frames), mass coefficients for wave loading, effects of marine growth on structural response, and the relation between static and dynamic load analysis procedures.\n\n5. A majority of the working group felt that there should be a separation of life safety, environmental consequences, and economic decisions for requalification but a consensus on this matter could not be reached.\n\n6. A full probability-of-failure risk analysis should be performed rather than a mere determination of the survival of a structure for a given return period earthquake.\n\n7. A strength level earthquake analysis need not be performed for requalification as long as a ductility level analysis is performed.\n\n8. A careful peer review should be conducted of both the structural and seismic hazard elements of any design, reassessment, or requalification process. More work is needed to develop an appropriate peer review process and guidelines for reviewer qualification.\n\n9. Research is needed to more precisely define manned and unmanned operations, and catastrophic consequences of environmental pollution.\n\n10. There is a need to build greater consensus on the appropriate criteria for safety goals for design and requalification. Further research is needed on such issues as: specification of life safety and environmental safety objectives, the use engineering judgment, and how to properly incorporate the consequences of failure into any performance objective.", "date": "1992-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1992.EERL.1992.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1992.EERL.1992.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Iwan_1992.pdf", "url": "https://authors.library.caltech.edu/records/rd01b-60w93/files/Iwan_1992.pdf" }, "pub_year": "1992", "author_list": "Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/fztx2-t8z50", "eprint_id": 26395, "eprint_status": "archive", "datestamp": "2023-08-20 00:58:00", "lastmod": "2023-10-24 16:18:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chiang-D-Y", "name": { "family": "Chiang", "given": "Dar-Yun" } } ] }, "title": "Parsimonious modeling of inelastic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1993", "abstract": "Analytical modeling of one-dimensional hysteresis and general multi-axial cyclic plasticity is studied, with particular emphasis on the parsimony of model parameters and the physical consistency of model behavior. General criteria for good models are proposed to provide guidelines to the modeling studies conducted in this research.\n\nVarious one-dimensional hysteretic models are examined in detail, including both deteriorating and non-deteriorating models. A general formulation for modeling of degrading systems is presented based on the formulation of the Distributed-Element Model (DEM) and the introduction of a damage index function. A new class of deteriorating Masing models, whose behavior can be completely described by a few simple mathematical rules and the extended Masing rules, is also developed to substitute for a special class of deteriorating DEMs, so that their applicabilty to system identification studies is improved.\n\nThe one-dimensional DEMs are extended to the multi-dimensional case for constitutive modeling of cyclic plasticity, while preserving the concept of modeling plasticity by an assemblage of simple ideal elasto-plastic elements. In the generalization, a new invariant-yield-surface theory is proposed, in which no kinematic hardening rule is needed to account for the subsequent yielding and strain hardening behavior. A general theory is also developed to elucidate some important properties of material behavior based on the proposed multi-dimensional DEMs. The establishment of the theory provides instructive insight into the elastic-plastic response mechanisms of real materials under complicated loading conditions. Based on the insight, the Masing rules for one-dimensional hysteresis are extended to the multi-dimensional case by introducing a composition of plane-geometry transformations to a response formula developed for initial loading. This transformation method serves as an efficient way of implementing the classical multi-yield-surface theory with the Mroz kinematic hardening rule. Validity of the new formulations are confirmed by comparison with experimental results from the literature.", "date": "1992-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1992.EERL-92-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1992.EERL-92-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9202.pdf", "url": "https://authors.library.caltech.edu/records/fztx2-t8z50/files/9202.pdf" }, "pub_year": "1992", "author_list": "Chiang, Dar-Yun" }, { "id": "https://authors.library.caltech.edu/records/85hqc-crf81", "eprint_id": 26393, "eprint_status": "archive", "datestamp": "2023-08-19 23:39:36", "lastmod": "2024-01-13 05:30:40", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-Robert-Teran", "name": { "family": "Beck", "given": "Robert Teran" } } ] }, "title": "Fundamental problems in the application of structural identification procedures to damage detection", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1991\n\nAccepted Version - 9103.pdf
", "abstract": "There are fundamental problems in the application of structural identification procedures to damage detection which still need to be resolved. The present study investigates the underlying issues and then provides a number of techniques which solve a series of unresolved problems. Tile techniques developed range from extensions and refinements of previous methods to the adaptation of novel homotopy methods.\n\nThe results from simulated data show that ill-conditionling, non-uniqueness and temporal synchronization of the data are the most serious problems encountered. Criteria to resolve these are then put forth. From the experimental studies, however, it becomes evident that modeling error is the most serious issue. The experimental results show, nonetheless, that even with large model errors, it is possible to localize the area of damage to within a sub-structure.\n\nThe techniques are then applied to data obtained from a ten-story steel frame building. Previous studies on such structures have indicated large changes in the natural frequencies, especially during the San Fernando earthquake of February 9, 1971. The present study shows how changes in the natural frequencies and in the modeshapes are related to the degradation of the inter-story stiffness along the height of the building. Low amplitude forced vibration and ambient vibration test data yield one set of results: at these levels of motion the structure seems to retain much of its original uniform stiffness. This is true even after strong motion, leading to the notion that the building \"has healed\" with time. It is clear from the studies how this apparent stiffness is lost immediately once the strong motion of even moderate earthquakes has begun and it is thought that this is due to a combinations of effects. Results show that for the 1971 San Fernando earthquake, stiffness losses in the order of 50% occurred in the middle stories towards the end of the strong motion part of the seismic motion.", "date": "1991-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1991.EERL-91-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1991.EERL-91-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9103.pdf", "url": "https://authors.library.caltech.edu/records/85hqc-crf81/files/9103.pdf" }, "pub_year": "1991", "author_list": "Beck, Robert Teran" }, { "id": "https://authors.library.caltech.edu/records/cvt8x-67s08", "eprint_id": 26392, "eprint_status": "archive", "datestamp": "2023-08-19 23:39:31", "lastmod": "2023-10-24 16:18:01", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hall-J-F", "name": { "family": "Hall", "given": "John F." }, "orcid": "0000-0002-7863-5060" }, { "id": "Dowling-M-J", "name": { "family": "Dowling", "given": "Michael J." } }, { "id": "El-Aidi-Bahaa", "name": { "family": "El-Aidi", "given": "Bahaa" } } ] }, "title": "Defensive design of concrete gravity dams", "ispublished": "unpub", "full_text_status": "public", "abstract": "Failure of a concrete gravity dam during an earthquake could occur as a sliding instability along an earthquake-induced crack, possibly assisted by uplift pressures from water flowing into the crack. Reliable assessment of the likelihood of such an event is thought to be difficult, and this suggests a need for designs which are less prone to cracking and uncertain behavior than are typical existing designs. Several schemes for reducing the potential for cracking during earthquake loading are investigated by finite element simulations: use of a sliding plane at the base of the dam, modification of the cross-sectional shape, use of a joint in the upper part of the clam, prestressing, and hydrodynamic isolation. The sliding plane, modified cross-section, and upper joint may only be applicable to new construction, while prestressing and hydrodynamic isolation could also be used to upgrade existing dams. While all of the schemes show potential, modification of the cross-sectional shape is probably the most practical considering acceptability, cost and effectiveness.", "date": "1991-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1991.EERL-91-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1991.EERL-91-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9102.pdf", "url": "https://authors.library.caltech.edu/records/cvt8x-67s08/files/9102.pdf" }, "pub_year": "1991", "author_list": "Hall, John F.; Dowling, Michael J.; et el." }, { "id": "https://authors.library.caltech.edu/records/tntyt-97192", "eprint_id": 26390, "eprint_status": "archive", "datestamp": "2023-08-19 22:22:18", "lastmod": "2024-01-13 05:30:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Levine-Marie-Bernard P", "name": { "family": "Levine", "given": "Marie-Bernard P." } } ] }, "title": "Accelerogram processing using reliability bounds and optimal correction methods", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1990: PB-91-170209/AS\n\nAccepted Version - 9002.pdf
", "abstract": "This study addresses the problem of obtaining reliable velocities and displacements from accelerograms, a concern which often arises in earthquake engineering. A closed-form acceleration expression with random parameters is developed to test any strong-motion accelerogram processing method. Integration of this analytical time history yields the exact velocities, displacements and Fourier spectra. Noise and truncation can also be added. A two-step testing procedure is proposed and the original Volume II routine is used as an illustration. The main sources of error are identified and discussed. Although these errors may be reduced, it is impossible to extract the true time histories from an analog or digital accelerogram because of the uncertain noise level and missing data. Based on these uncertainties, a probabilistic approach is proposed as a new accelerogram processing method. A most probable record is presented as well as a reliability interval which reflects the level of error-uncertainty introduced by the recording and digitization process. The data is processed in the frequency domain, under assumptions governing either the initial value or the temporal mean of the time histories. This new processing approach is tested on synthetic records. It induces little error and the digitization noise is adequately bounded. Filtering is intended to be kept to a minimum and two optimal error-reduction methods are proposed. The \"noise filters\" reduce the noise level at each harmonic of the spectrum as a function of the signal-to-noise ratio. However, the correction at low frequencies is not sufficient to significantly reduce the drifts in the integrated time histories. The \"spectral substitution method\" uses optimization techniques to fit spectral models of near-field, far-field or structural motions to the amplitude spectrum of the measured data. The extremes of the spectrum of the recorded data where noise and error prevail are then partly altered, but not removed, and statistical criteria provide the choice of the appropriate cutoff frequencies. This correction method has been applied to existing strong-motion far-field, near-field and structural data with promising results. Since this correction method maintains the whole frequency range of the record, it should prove to be very useful in studying the long-period dynamics of local geology and structures.", "date": "1990-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1990.EERL-90-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1990.EERL-90-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "9002.pdf", "url": "https://authors.library.caltech.edu/records/tntyt-97192/files/9002.pdf" }, "pub_year": "1990", "author_list": "Levine, Marie-Bernard P." }, { "id": "https://authors.library.caltech.edu/records/pp3v3-41797", "eprint_id": 26435, "eprint_status": "archive", "datestamp": "2023-08-19 21:19:12", "lastmod": "2023-10-24 16:19:26", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "US-China Joint Project on Strong Ground Motion Measurements", "name": { "family": "US-China Joint Project on Strong Ground Motion Measurements" } } ] }, "title": "Digital near source accelerograms recorded by instrumental arrays in Tangshan, China. Part I (1982.7-1984.12)", "ispublished": "unpub", "full_text_status": "public", "note": "PB-91-154112", "abstract": "The ultimate goal of earthquake hazard mitigation research is to gain sufficient understanding of the phenomena involved in an earthquake to minimize the loss of life and property resulting from such an event. In order to design safe, economical structures and facilities in seismic areas, it is necessary to understand the nature of the ground motion generated by an earthquake. This understanding can ultimately come only from the measurement of the strong ground motion resulting from actual damaging earthquakes.\n\nIn order to facilitate the acquisition of strong ground motion data world-wide, an International Workshop on Strong Motion Earthquake Instrument Arrays was held in 1978 in Hawaii. Participants in the Workshop appealed to the earthquake-threatened countries of the world to undertake a concerted effort to establish strong-motion accelerograph arrays and networks.\n\nIn response to the appeal of these experts in earthquake hazard mitigation, and in accord with the \"China-U.S. Protocol for Scientific and Technical Cooperation in Earthquake Studies,\" a joint research project on strong ground motion measurement has been established in China.\n\nIn the first phase of this project, from April 1981 to December 1984, 22 Kinemetrics PDR-1 Digital Event Recorders equipped with FBA-13 Force Balance Accelerometers, and 18 Kinemetrics SMA-1 Analog Accelerographs were deployed in China. Of this total, 13 PDR-1 and 3 SMA1 instruments were deployed in a surface array and a three-dimensional array in the aftershock region of the 1976 Tangshan earthquake.\n\nThese two arrays recorded a total of 1053 near-source accelerograms from 416 earthquakes with magnitudes ranging from ML = 1.2 to 5.7. The source-station distances ranged from 2 to 45 kilometers. Most of the records contain the complete P- and S-wave motion along with accurate absolute time. Both the volume and quality of the accelerograms are much greater than ever before obtained in China.\n\nThe largest event recorded was the ML = 5.7 Lulong earthquake of October 19, 1982. Nine instruments were triggered by this event. The epicentral distance from the recording stations ranged from 5 to 41 kilometers, and the corresponding peak horizontal acceleration ranged from 0.217 to 0.008g.\n\nAccelerograms were recorded by the three-dimensional array from twenty-eight events. Measurements were made to a depth of 900 meters below the ground surface. The records obtained provide a unique source of data for the study of the propagation of seismic waves near the earth's surface. In order to make these data more useful, they will be published along with site data in a separate volume.\n\nIn this report, 218 of the most significant accelerograms; are published. The data was obtained from earthquakes with magnitudes ranging from ML = 2.3 to 5.7. All of the data reproduced in this report is available on 9-track computer tape.", "date": "1989-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1989.EERL-89-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1989.EERL-89-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8904.pdf", "url": "https://authors.library.caltech.edu/records/pp3v3-41797/files/8904.pdf" }, "pub_year": "1989", "author_list": "US-China Joint Project on Strong Ground Motion Measurements" }, { "id": "https://authors.library.caltech.edu/records/dv9zq-bnm69", "eprint_id": 26388, "eprint_status": "archive", "datestamp": "2023-08-19 21:18:59", "lastmod": "2023-10-24 16:17:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thyagarajan-R-S", "name": { "family": "Thyagarajan", "given": "Ravi Shanker" } } ] }, "title": "Modeling and analysis of hysteretic structural behavior", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1990: PB-91-154195\n\nPublished - 8903.pdf
", "abstract": "For damaging response, the force-displacement relationship of a structure is highly nonlinear and history-dependent. For satisfactory analysis of such behavior, it is important to be able to characterize and to model the phenomenon of hysteresis accurately. A number of models have been proposed for response studies of hysteretic structures, some of which are examined in detail in this thesis. There are two popular classes of models used in the analysis of curvilinear hysteretic systems. The first is of the distributed element or assemblage type, which models the physical behavior of the system by using well-known building blocks. The second class of models is of the differential equation type, which is based on the introduction of an extra variable to describe the history dependence of the system.\n\nOwing to their mathematical simplicity, the latter models have been used extensively for various applications in structural dynamics, most notably in the estimation of the response statistics of hysteretic systems subjected to stochastic excitation. But the fundamental characteristics of these models are still not clearly understood. A response analysis of systems using both the Distributed Element model and the differential equation model when subjected to a variety of quasi-static and dynamic loading conditions leads to the following conclusion: Caution must be exercised when employing the models belonging to the second class in structural response studies as they can produce misleading results.\n\nThe Massing's hypothesis, originally proposed for steady-state loading, can be extended to general transient loading as well, leading to considerable simplification in the analysis of the Distributed Element models. A simple, nonparametric identification technique is also outlined, by means of which an optimal model representation involving one additional state variable is determined for hysteretic systems.", "date": "1989-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1989.EERL-89-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1989.EERL-89-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8903.pdf", "url": "https://authors.library.caltech.edu/records/dv9zq-bnm69/files/8903.pdf" }, "pub_year": "1989", "author_list": "Thyagarajan, Ravi Shanker" }, { "id": "https://authors.library.caltech.edu/records/khcxm-cxc49", "eprint_id": 26383, "eprint_status": "archive", "datestamp": "2023-08-19 19:16:30", "lastmod": "2023-10-24 16:17:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Whirley-R-G", "name": { "family": "Whirley", "given": "Robert Gary" } } ] }, "title": "Random response of nonlinear continuous systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1988: PB-89-194153/AS", "abstract": "This thesis presents a technique for obtaining the stochastic response of a nonlinear continuous system. First, the general method of nonstationary continuous equivalent linearization is developed. This technique allows replacement of the original nonlinear system with a time-varying linear continuous system. Next, a numerical implementation is described which allows solution of complex problem on a digital computer. In this procedure, the linear replacement system is discretized by the finite element method. Application of this method to systems satisfying the one-dimensional wave equation with two different types of constitutive nonlinearities is described. Results are discussed for nonlinear stress-strain laws of both hardening and softening types", "date": "1987-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1987.EERL-87-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1987.EERL-87-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8704.pdf", "url": "https://authors.library.caltech.edu/records/khcxm-cxc49/files/8704.pdf" }, "pub_year": "1987", "author_list": "Whirley, Robert Gary" }, { "id": "https://authors.library.caltech.edu/records/ekezz-q7137", "eprint_id": 26376, "eprint_status": "archive", "datestamp": "2023-08-19 17:31:54", "lastmod": "2023-10-24 16:17:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-Robert-Teran", "name": { "family": "Beck", "given": "Robert Teran" } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "Comparison between transfer function and modal minimization methods for system identification", "ispublished": "unpub", "full_text_status": "public", "note": "PB-87-234688/A04", "abstract": "The reliability of two methods of structural identification is assessed employing noise-contaminated data.\n\nThe statistical properties of the results of the transfer function approach and those of the modal minimization technique are compared, at different levels of noise, with the exact values of the modal parameters being estimated. Comparison indicates that the modal minimization is a far superior technique for structural parameter estimation using linear models.", "date": "1985-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1985.EERL-85-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1985.EERL-85-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8506.pdf", "url": "https://authors.library.caltech.edu/records/ekezz-q7137/files/8506.pdf" }, "pub_year": "1985", "author_list": "Beck, Robert Teran and Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/ymf6m-4by25", "eprint_id": 26375, "eprint_status": "archive", "datestamp": "2023-08-19 17:19:36", "lastmod": "2024-01-13 05:30:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chelvakumar-Kasivisvanathan", "name": { "family": "Chelvakumar", "given": "Kasivisvanathan" } } ] }, "title": "A Simple strain-space plasticity model for clays", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-87-234308/CC\n\nAccepted Version - 8505.pdf
", "abstract": "This thesis develops and demonstrates a simple strain-space constitutive model for wet clays. It has been seen that a strain-space formulation of the constitutive behavior of engineering materials facilitates the solution of boundary value problems involving these materials. Soil, because of its multi-phase granular constitution poses challenging problems in constitutive modeling. Although several stress-space plasticity models exist for soils. they are not used commonly in engineering practice due to their complexity. It is attempted herein to develop and test a simple model which could result in simplified solutions for some soil problems.\n\nThe model is based on the experimentally observed physical behavior of soil. Certain approaches alien to conventional plasticity, are employed so that the material behavior is closely predicted without sacrificing the simplicity of the model.\n\nThe model is initially developed for triaxial load systems. Its predictions are then tested against other model predictions and experimental data. The model is then generalized. The generalization renders the model capable of handling general stress-strain states and finite deformations.\n\nFinally, the generalized model is used to solve an idealization of a practical problem. The problem of a pile driven into a soil medium is idealized as an expanding cavity in a homogeneous infinite medium. The solution predicted by the strain-space model is compared with other model predictions and test results.", "date": "1984-12-05", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-85-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-85-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8505.pdf", "url": "https://authors.library.caltech.edu/records/ymf6m-4by25/files/8505.pdf" }, "pub_year": "1984", "author_list": "Chelvakumar, Kasivisvanathan" }, { "id": "https://authors.library.caltech.edu/records/s03tx-9zz34", "eprint_id": 26369, "eprint_status": "archive", "datestamp": "2023-08-19 16:37:33", "lastmod": "2023-10-24 16:17:13", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } }, { "id": "Moser-Michael-Anthony", "name": { "family": "Moser", "given": "Michael Anthony" } }, { "id": "Peng-Chia-Yen", "name": { "family": "Peng", "given": "Chia-Yen" } } ] }, "title": "Strong-motion earthquake measurement using a digital accelerograph", "ispublished": "unpub", "full_text_status": "public", "note": "PB-91-170191/AS", "abstract": "This paper presents results of a study of some of the characteristics of the Kinemetrics PDR-1 digital strong-motion accelerograph. The paper gives the results of laboratory tests of the background noise level of the instrument and compares these results with previously reported observations for optical instruments. The determination of displacement from acceleration data is discussed and results of laboratory tests are presented. Certain instrument anomalies are identified, data correction algorithms proposed, and examples given. The paper also presents the results of a comparison of earthquake records obtained from side-by-side digital and optical analog instruments. Finally, some results obtained from a recent Chinese earthquake are discussed.", "date": "1984-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-84-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-84-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8402.pdf", "url": "https://authors.library.caltech.edu/records/s03tx-9zz34/files/8402.pdf" }, "pub_year": "1984", "author_list": "Iwan, Wilfred D.; Moser, Michael Anthony; et el." }, { "id": "https://authors.library.caltech.edu/records/aqee2-mkw24", "eprint_id": 26258, "eprint_status": "archive", "datestamp": "2023-08-19 16:37:29", "lastmod": "2023-10-24 16:15:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "John Charles" } } ] }, "title": "Analysis of the observed earthquake response of a multiple span bridge", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1984: PB-85-240505/AS", "abstract": "Accelerograms obtained during the 1979 Coyote Lake, California earthquake are used to examine the response of a multiple-span, steel girder bridge to strong earthquake loading. The structure studied, the San Juan Bautista 156/101 Separation Bridge, is typical of many highway bridges in seismic regions of the United States. Although the bridge was not damaged, the strong-motion records are of significant engineering interest as they are the first to be recorded on such a structure.\n\nAn engineering seismology study suggests that long-period ground displacements at the bridge site were caused by Rayleigh waves. A three-second period, pseudostatic response of the superstructure is attributed to small amounts of differential support motion induced by the surface waves.\n\nA time-domain technique of system identification is used to determine linear models which can closely replicate the observed bridge response. Using time-invariant models, two structural modes at 3.50 and 6.33 Hz, are identified in the horizontal direction. Each mode, having approximately ten-percent damping, involves coupled longitudinal and transverse motions of the superstructure. Time-variations of frequency and damping in the horizontal response are also identified using a moving-window analysis.\n\nA three-dimensional finite element model which includes soil-structure interaction predicts several important features of the dynamic response of the bridge. The first two computed horizontal frequencies are found to be in excellent agreement with the observed responses provided the model's expansion joints are locked, preventing relative translational motions from occurring across the joints. Locking is confirmed by the observed deformations of the structure in the fundamental mode. Fundamental vertical frequencies of the individual spans, predicted by the finite element model, are in very good agreement with ambient vibration test data. Results of the strong-motion data analysis and the finite element modeling are used to recommend a plan for expansion of the strong-motion instrumentation array on the bridge.", "date": "1984-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-84-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-84-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8401.pdf", "url": "https://authors.library.caltech.edu/records/aqee2-mkw24/files/8401.pdf" }, "pub_year": "1984", "author_list": "Wilson, John Charles" }, { "id": "https://authors.library.caltech.edu/records/eskj1-kfx17", "eprint_id": 26371, "eprint_status": "archive", "datestamp": "2023-08-19 16:37:38", "lastmod": "2023-10-24 16:17:17", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Smith-K-S", "name": { "family": "Smith", "given": "Kenneth Scott" } } ] }, "title": "Stochastic analysis of the seismic response of secondary systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1985: PB-85-240497/AS", "abstract": "This thesis is concerned with the earthquake response of light equipment in structures. The motion of the ground during an earthquake is represented as a stochastic process in order to reflect uncertainty in the prediction of such motion. A number of different stochastic earthquake models are considered, and analytical methods are described for these models.\n\nThe response of equipment in a structure to stochastic ground motion is derived, in the case of a single-degree-of-freedom secondary system (equipment) attached to a single-dogree-of-freedom structure. The distribution of the envelope of the secondary system displacement is obtained for general transient ground motion. Closed form expressions are computed for the transient response to stationary ground motion.\n\nThe effect of the interaction of equipment with the structure is described by the introduction of an equivalent non-interacting system. However, this method applies only to classically damped systems.\n\nThe results are applied in a simple way to the problem of the computation of floor spectra. It is found that the ground spectrum is amplified in a simple way, except near resonance, where special considerations Must be addressed.", "date": "1984-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1984.EERL-85-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1984.EERL-85-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8501.pdf", "url": "https://authors.library.caltech.edu/records/eskj1-kfx17/files/8501.pdf" }, "pub_year": "1984", "author_list": "Smith, Kenneth Scott" }, { "id": "https://authors.library.caltech.edu/records/vx43w-6zp48", "eprint_id": 26367, "eprint_status": "archive", "datestamp": "2023-08-19 15:42:06", "lastmod": "2023-10-24 16:17:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "McVerry-Graeme-Haynes", "name": { "family": "McVerry", "given": "Graeme Haynes" } }, { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "Structural identification of JPL Building 180 using optimally synchronized earthquake records", "ispublished": "unpub", "full_text_status": "public", "note": "PB-84-162833", "abstract": "Linear models of JPL Building 180 were identified from its strong-motion records obtained in the 1971 San Fernando earthquake using two system identification techniques, both of which revealed a previously undetected time-shift of about 0.08 second between the digitized basement and roof records. Optimal alignment of the records produced improved matches between the measured and model responses, and overcame difficulties encountered in extracting physically reasonable estimates for the parameters of the third and higher modes from the original records.\n\nThe two complementary identification techniques provide optimal estimates with standard errors for the periods, dampings and effective participation factors of the dominant modes in the response. One method performs a least-squares match between the calculated and recorded response in the time domain, and the other in the frequency domain. Akaike's information criterion is used to determine the number of modes to include in the models.\n\nThe fundamental periods identified for JPL Building 180 lengthened during the response by 40% and 60% for the longitudinal and transverse directions respectively, starting from values close to those measured in vibration tests. The effective overall damping factors for the fundamental modes in the two directions were 3.6% and 4.4% of critical.", "date": "1983-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1983.EERL-83-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1983.EERL-83-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8301.pdf", "url": "https://authors.library.caltech.edu/records/vx43w-6zp48/files/8301.pdf" }, "pub_year": "1983", "author_list": "McVerry, Graeme Haynes and Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/9ztyf-y1f26", "eprint_id": 26366, "eprint_status": "archive", "datestamp": "2023-08-19 14:49:48", "lastmod": "2023-10-24 16:17:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rashed-A", "name": { "family": "Rashed", "given": "Ahmed" } } ] }, "title": "Dynamic analyses of fluid-structure systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1983: PB-84-162916", "abstract": "Theoretical investigations of the dynamic behavior of some important fluid-structure systems are conducted to seek a better understanding of: 1) the hydrodynamic pressures generated in the fluid as a result of both the rigid body and the vibrational motions of the structure, and 2) the effects of the fluid on the dynamic properties of the structure as well as on its response to earthquake ground motions.\n\nExplicit formulas are presented for the hydrodynamic pressures generated in fluid domains having boundaries which can be approximated by simple geometries. Such domains may be reservoirs behind dams, or around intake towers, water around bridge piers or liquids stored in circular cylindrical tanks. The formulas are used to calculate the hydrodynamic pressures analytically and the results are exhibited in a form showing the pressure dependence on the various parameters of the problem.\n\nThe fluid-structure interaction problems of long straight walls, having uniform rectangular sections, and long straight gravity dams, having uniform triangular sections, are investigated. The natural frequencies of vibration and the associated mode shapes are found in the former case, through a fully analytical approach for both the structure and the fluid domains, and in the latter, by discretizing the dam into finite elements and treating the reservoir as a continuum by boundary solution techniques. A method is presented for computing the earthquake response of both structures, based on superposition of their free vibrational modes.\n\nThe problems of limited length dam or wall-reservoir systems are investigated. The natural frequencies of the structure and the corresponding mode shapes are found by the Rayleigh-Ritz method. This method is also used to obtain the frequency domain response of the structure to all three components of the ground motion. The validity of the two dimensional approximation, often made in the analysis of gravity dams, and the effect of the length to height ratio on the dynamic properties and response of the structure are studied.\n\nTime domain responses to arbitrary earthquake ground notions are evaluated by superposing the frequency domain responses, to individual Fourier components of the excitation, through the Fourier Integral. For efficiency of computation, a fast Fourier analysis is used for both the forward transform of the ground excitation and the inverse transform of the Fourier Integral.", "date": "1982-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1982.EERL-82-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1982.EERL-82-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8203.pdf", "url": "https://authors.library.caltech.edu/records/9ztyf-y1f26/files/8203.pdf" }, "pub_year": "1982", "author_list": "Rashed, Ahmed" }, { "id": "https://authors.library.caltech.edu/records/4v10y-gfb65", "eprint_id": 26363, "eprint_status": "archive", "datestamp": "2023-08-19 13:52:54", "lastmod": "2023-10-24 16:17:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shih-C-F", "name": { "family": "Shih", "given": "Choon-Foo" } } ] }, "title": "Failure of liquid storage tanks due to earthquake excitation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1982: PB-82-215013", "abstract": "Above ground liquid storage tanks have suffered serious damage during earthquakes. The damage of tanks can vary from local yielding or buckling of the tank wall, to loss of contents, or to collapse which leads to an unrepairable tank. Considerable work has been carried out on this problem with varying degree of success. However, the results are largely directed toward response rather than failure prediction. The information on failure mechanisms is very limited. The present work consists of scale model testing, correlation with existing analysis and failure prediction with laboratory verification. The scale model testing incorporates dynamic similarity of the fluid/structure interaction problem. The model study shows that small plastic models can be useful in studying the dynamics and buckling of liquid-filled tanks under ground excitation even though the model does not display complete similitude, The buckling criterion proposed in this study is based upon static considerations and the complex stress field in the shell wall is supplanted by a simple field for which analytical/ experimental results are available. Harmonic buckling tests demonstrate that the static buckling criterion is satisfactory even though the prebuckling stress field is time dependent, The harmonic buckling tests, when correlated with the stresses from a response analysis, also indicate that the buckling is largely dependent upon the n=1 response, Transient buckling tests are also carried out and the results show that the linear analysis together with the static buckling criterion gives a good prediction of the failure of a full fluid-filled tank. The test parameters in these buckling tests include water depth, title angle, thickness of tank wall, top end condition, ground excitation pattern, etc. In addition, buckling tests of unanchored tanks are conducted to study the influence of changing the anchorage of the tank base. An analytical model is suggested to predict the response of an unanchored tank due to overturning moment. The current design criterion of an unanchored tank is also. assessed in this study. The results of this investigation, in addition to those carried out previously, provide a better understanding of the forced vibration problem, failure criterion and appropriate design procedure for a liquid storage tank.", "date": "1981-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1981.EERL-81-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1981.EERL-81-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8104.pdf", "url": "https://authors.library.caltech.edu/records/4v10y-gfb65/files/8104.pdf" }, "pub_year": "1981", "author_list": "Shih, Choon-Foo" }, { "id": "https://authors.library.caltech.edu/records/8vkv3-ym981", "eprint_id": 26362, "eprint_status": "archive", "datestamp": "2023-08-19 13:52:48", "lastmod": "2023-10-24 16:16:58", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Psycharis-I-N", "name": { "family": "Psycharis", "given": "Ioannis N." } } ] }, "title": "Dynamic behavior of rocking structures allowed to uplift", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1982: PB-82-212945", "abstract": "Strong shaking of structures during large earthquakes may result in some cases in partial separation of the base of the structure from the sail. This phenomenon of uplifting, which can affect the dynamic behavior of the structure significantly, even if the amount of uplift is small, is examined in this thesis. First the case of a rocking rigid block is investigated and then more complicated, flexible superstructures are introduced. Two foundation models which permit uplift are considered: the Winkler foundation and the much simpler \"two-spring\" foundation. Several energy dissipating mechanisms are also introduced into these models. It is shown that an equivalence between these two models for the foundation can be established, so that one can always work with the much simpler two-spring foundation. In this way complete analytical solutions can be derived in most cases. Moreover, simple approximate methods for the calculation of the apparent fundamental period of the rocking system are developed and simplified methods of analysis are proposed.\n\nIn general, uplift leads to a softer vibrating system which behaves nonlinearly, although the response is composed of a sequence of linear responses. As a result, the apparent fundamental resonant frequency of the uplifting system is always less than the fundamental resonant frequency of both the soil-structure interacting system, in which lift-off is not allowed, and the superstructure itself. The second and higher resonant frequencies of the superstructure, however, are not affected significantly by lift-off. For damped foundations, the ratio of critical damping associated with the apparent fundamental mode decreases, in general, with the amount of lift-off. These effects of uplift on the dynamic properties of the rocking system can alter the response of the structure significantly during an earthquake. Nevertheless, it cannot be said a priori whether they are favorable to the behavior or not; this depends on the parameters of the system and the time history of the excitation.", "date": "1981-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1981.EERL-81-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1981.EERL-81-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8102.pdf", "url": "https://authors.library.caltech.edu/records/8vkv3-ym981/files/8102.pdf" }, "pub_year": "1981", "author_list": "Psycharis, Ioannis N." }, { "id": "https://authors.library.caltech.edu/records/cqjmj-ez386", "eprint_id": 26537, "eprint_status": "archive", "datestamp": "2023-08-19 13:53:06", "lastmod": "2023-10-24 16:23:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "U.S. Strong-Motion Earthquake Instrumentation: Proceedings of the U.S. National Workshop on Strong-Motion Earthquake Instrumentation", "ispublished": "unpub", "full_text_status": "public", "note": "sponsored by Grant No. PFR80-18271 from the National Science Foundation", "abstract": "The U.S. National Workshop on Strong-Motion Earthquake Instrumentation was held April 12-14, 1981 on the campus of Westmont College in Santa Barbara, California. The Workshop was organized by a Steering Committee appointed by the Earthquake Engineering Research Institute and the Universities Council for Earthquake Engineering Research. This volume is the product of the combined efforts of those in attendance.\n\nThe objectives of the Workshop were: 1) to review existing strong-motion Instrumentation programs in the U.S., 2) to develop a unified strategy for the deployment of strong-motion instruments both in the free-field and in buildings, and 3) to formulate a plan for the coordination of existing strong-motion programs, the on-going installation and operation of instruments and the management of strong-motion data. To achieve these objectives, the Workshop was organized into a number of Working Committees covering the major areas to be addressed. The reports of the Individual Working Committees are incorporated as chapters in this volume.\n\nExperts in earthquake engineering and seismology were invited from all over the nation to participate in the Workshop. In addition, experts were invited from a number of foreign countries. Prior to the Workshop a Strong-Motion Instrumentation Survey was sent to all U.S. organizations known to have active strong-motion programs. The results of this Survey were made available to the Workshop delegates and are included in this volume.", "date": "1981-01-01", "date_type": "published", "publisher": "Earthquake Engineering Research Laboratory", "id_number": "CaltechEERL:1981.EERL.1981.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1981.EERL.1981.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Iwan_wd_1981.pdf", "url": "https://authors.library.caltech.edu/records/cqjmj-ez386/files/Iwan_wd_1981.pdf" }, "pub_year": "1981", "author_list": "Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/ph264-bc013", "eprint_id": 26359, "eprint_status": "archive", "datestamp": "2023-08-19 13:29:56", "lastmod": "2024-01-13 05:29:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krousgrill-Charles-Morton", "name": { "family": "Krousgrill", "given": "Charles Morton" } } ] }, "title": "A linearization technique for the dynamic response of nonlinear continua", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1981: PB-82-201823\n\nAccepted Version - 8008.pdf
", "abstract": "The efforts of this dissertation are directed toward the development of a technique for understanding the dynamic response of structural elements governed by nonlinear partial differential equations. This technique is based on the concepts of the equivalent linearization method which relies on obtaining an optimal linear set of equations to model the original nonlinear set.\n\nIn this method, the linearization is performed at the continuum level. At this level, the equivalent linear stiffness and damping parameters are physically realizable and are defined in such a way that the method can be easily be incorporated into finite element computer codes.\n\nThree different approaches to the method are taken with each approach based on the minimization of a distinct difference between the nonlinear system and its linear replacement, Existence and uniqueness properties of the minimizat4on solutions are established.\n\nThe method is specialized for the treatment of steady-state solutions to harmonic excitation and of stationary response to random excitation. Procedures for solving the equivalent linearization are also discussed.\n\nThe method is applied to three specific examples: one dimensional, hysteretic shear beams, thin plates governed by nonlinear equations of motion and the same nonlinear thin plates but with cutouts. Solutions via the equivalent linearization method using the stress difference minimization compare well with Galerkin's method and numerical integration. The last example is easily handled by the continuum equivalent linearization technique, whereas other methods prove to be inadequate.", "date": "1980-09-24", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-08", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-08", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8008.pdf", "url": "https://authors.library.caltech.edu/records/ph264-bc013/files/8008.pdf" }, "pub_year": "1980", "author_list": "Krousgrill, Charles Morton" }, { "id": "https://authors.library.caltech.edu/records/dv580-94t88", "eprint_id": 26433, "eprint_status": "archive", "datestamp": "2023-08-19 12:59:29", "lastmod": "2023-10-24 16:19:21", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rutenberg-A", "name": { "family": "Rutenberg", "given": "Avigdor" } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "The response of Veteran's Hospital building 41 in the San Fernando earthquake", "ispublished": "unpub", "full_text_status": "public", "abstract": "Structures which collapse or are heavily damaged in destructive earthquakes are analyzed by engineers to determine why they performed so poorly and to find out how their design could have been improved. However, it is equally important for buildings that survived exceptionally strong shaking to be analyzed and an explanation given as to why they were able to do so.\n\nDuring the San Fernando, California earthquake of February 9, 1971 buildings in the strongly shaken region showed both types of performance. For example, the new Olive View Hospital main building was severely damaged, and another major building collapsed whereas two buildings at the Veteran's Administration (VA) Hospital survived with no significant damage. These two hospitals were located just north of the major surface faulting, and the VA buildings were only V-, miles southwest of Pacoima Dam. The Dam was effectively over the center of energy release of the magnitude of 6.4 earthquake and the well-known Pacoima Dam accelerogram, with peak accelerations over 1g, was recorded on a steep ridge near the abutment of the Dam. The ground shaking at the VA hospital is thought to have been less severe than that recorded at Pacoima Dam, but more severe than that recorded at the Holiday Inn, which was approximately five miles south of the nearest point on the causative fault.\n\nTwo major structures collapsed at the Veteran's Administrative Hospital killing 46 persons, which accounted for most of the casualties in the earthquake. These buildings were constructed in the 1920's and were not designed to resist earthquakes. Within the immediate neighborhood of these collapsed buildings were two other major structures that were built in the 1930's and the 1940's in accordance with building codes requiring earthquake resistance, and these survived the San Fernando earthquake without significant damage. One of these structures is the subject of this report.", "date": "1980-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8003.pdf", "url": "https://authors.library.caltech.edu/records/dv580-94t88/files/8003.pdf" }, "pub_year": "1980", "author_list": "Rutenberg, Avigdor; Jennings, Paul C.; et el." }, { "id": "https://authors.library.caltech.edu/records/9akc1-j0d88", "eprint_id": 26356, "eprint_status": "archive", "datestamp": "2023-08-19 12:59:19", "lastmod": "2024-01-13 05:29:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haroun-Medhat Ahmed", "name": { "family": "Haroun", "given": "Medhat Ahmed" } } ] }, "title": "Dynamic analyses of liquid storage tanks", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1980: PB-81-123275\n\nAccepted Version - 8004.pdf
", "abstract": "Theoretical and experimental investigations of the dynamic behavior of cylindrical liquid storage tanks are conducted to seek possible improvements in the design of such tanks to resist earthquakes. The study is carried out in three phases: 1) a detailed theoretical treatment of the liquid-shell system, 2) an experimental investigation of the dynamic characteristics of full-scale tanks, and 3) a development of an improved design-procedure based on an approximate analysis.\n\nNatural frequencies of vibration and the associated mode shapes are found through the use of a discretization scheme in which the elastic shell is modeled by finite elements and the fluid region is treated as a continuum by boundary solution techniques. In this approach, the number of unknowns is substantially less than in those analyses where both tank wall and fluid are subdivided into finite elements. A method is presented to compute the earthquake response of both perfect circular and irregular tanks; it is based on superposition of the free lateral vibrational modes. Detailed numerical examples are presented to illustrate the applicability and effectiveness of the analysis and to investigate the dynamic characteristics of tanks with widely different properties. Ambient and forced vibration tests are conducted on three full-scale water storage tanks to determine their dynamic characteristics. Comparison with previously computed mode shapes and frequencies shows good agreement with the experimental results, thus confirming the reliability of the theoretical analysis. Approximate solutions are also developed to provide practicing engineers with simple, fast, and sufficiently accurate tools for estimating the seismic response of storage tanks.", "date": "1980-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Earthquake Research Affiliates Program of Caltech" } ] }, "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "doi": "10.7907/1JZR-HK48", "primary_object": { "basename": "8004.pdf", "url": "https://authors.library.caltech.edu/records/9akc1-j0d88/files/8004.pdf" }, "pub_year": "1980", "author_list": "Haroun, Medhat Ahmed" }, { "id": "https://authors.library.caltech.edu/records/2sjf3-mxv23", "eprint_id": 26358, "eprint_status": "archive", "datestamp": "2023-08-19 12:59:24", "lastmod": "2023-10-24 16:16:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yoder-P-J", "name": { "family": "Yoder", "given": "Paul Jerome" } } ] }, "title": "A strain-space plasticity theory and numerical implementation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1981: PB-82-201682", "abstract": "This thesis sets forth an alternate version of plasticity which closely parallels the traditional theory but interchanges the roles of stress and strain. As a result, the new formulation gives stress as a functional of strain, rather than the reverse, and is thus attuned to the needs of the dynamicist.\n\nIn the case of a single loading surface, the two versions of plasticity are shown to be equivalent when the model parameters are appropriately selected. A similar though less satisfying result is obtained for formulations involving a plurality of loading surfaces.\n\nThe strain-space formulation is coded for numerical solution, with provision for a variable number of loading surfaces. The numerical algorithm is tested for accuracy in the handling of perfect plasticity, and the results are compared with those given by three commonly-used stress-space algorithms. The new algorithm is then interfaced with a finite element code and used to study the response of a foundation resting on an elastoplastic half-space.", "date": "1980-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8007.pdf", "url": "https://authors.library.caltech.edu/records/2sjf3-mxv23/files/8007.pdf" }, "pub_year": "1980", "author_list": "Yoder, Paul Jerome" }, { "id": "https://authors.library.caltech.edu/records/ey8je-sxc27", "eprint_id": 26355, "eprint_status": "archive", "datestamp": "2023-08-19 12:59:12", "lastmod": "2023-10-24 16:16:43", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } }, { "id": "Scott-R-F", "name": { "family": "Scott", "given": "Ronald F." } }, { "id": "Craig-M-J", "name": { "family": "Craig", "given": "Michael J." } } ] }, "title": "Full-scale experimental investigation of a modern earth dam", "ispublished": "unpub", "full_text_status": "public", "note": "PB-81-123788", "abstract": "An extensive investigation has been made based on the results of full-scale dynamic tests performed on a modern earth dam, Santa Felicia Cam in Southern California. This dam was chosen for the experimental studies because it had been subjected to strong shaking during two earthquakes: the strong, 6.3 local Richter magnitude San Fernando earthquake of 1971, and a 1976 earthquake of magnitude 4.7. The records recovered from these two earthquakes provided usable information on the dynamic characteristics of the dam which was instrumented with motion sensors to yield data on the structural response as well as the input ground motion at the site.\n\nIn the test programs, various types of dynamic excitations were used including mechanical vibration, ambient vibration, hydrodynamically generated forces, and the two strong seismic ground motions; thus, the imposed dynamic forces varied greatly in their time-history characteristics, spatial distributions, and intensities. For the forced vibration tests, the dam was excited into resonance in the upstream-downstream direction and in the longitudinal direction by a coupled pair of mechanical vibration generators (200 feet apart) capable of producing force up to 10,000 lbs. Symmetric and antisymmetric vibrations were separated by synchronizing the two shakers to run in-phase and 1800 out-of-phase, respectively, with the aid of control units. During the ambient vibration tests, the naturally occurring vibrations of the dam caused by strong wind and the spilling of the reservoir were measured. The test of dam response to hydrodynamic forces involved the use of pressure waves (to impinge upon the upstream face of the dam) originating from a controlled, submerged release of gas under pressure in the reservoir water. During the dynamic tests, three-dimensional measurements of the motions of approximately 25 stations along the crest and seven stations on the downstream slope were recorded and then analyzed in both time and frequency domains. Modes of vibrations and associated natural frequencies as well as damping ratios were determined in the frequency range from 0.0 to 6.0 Hz. The reliability of the existing analytical techniques for earth dams, which are restricted to horizontal shear deformation in the upstreamdownstream direction, was examined. Finally, in order to reveal any change in the dynamic properties of the dam, the dam's natural frequencies, mode shapes, dynamic shear moduli and damping factors (the latter two as functions of the induced strains) estimated from the measured responses to the two earthquakes were compared with those determined from the full-scale dynamic excitation tests.", "date": "1980-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8002.pdf", "url": "https://authors.library.caltech.edu/records/ey8je-sxc27/files/8002.pdf" }, "pub_year": "1980", "author_list": "Abdel-Ghaffar, Ahmed Mansour; Scott, Ronald F.; et el." }, { "id": "https://authors.library.caltech.edu/records/8hn54-vaw12", "eprint_id": 26354, "eprint_status": "archive", "datestamp": "2023-08-19 12:59:07", "lastmod": "2023-10-24 16:16:41", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-D-M", "name": { "family": "Lee", "given": "David M." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "A Selection of important strong motion earthquake records", "ispublished": "unpub", "full_text_status": "public", "note": "PB-80-169196", "abstract": "This report is a condensed collection of 45 strong and/or historically important earthquake-generated ground and building motions. These data are presented as accelerogram and integrated velocity and displacement time histories. Linear, absolute acceleration, relative velocity and relative displacement response spectra are given for all the ground motions presented. As a major aim of this report was to allow comparisons of different ground motions, the time history and response spectra plots were plotted, wherever possible, to fixed vertical and horizontal scales.\n\nA short introduction is given to earthquake recording instruments and recording networks using these devices. The sources from which the data in this report were drawn are identified and information given to enable one to obtain printed copies or magnetic tape copies of these data or any of the other earthquake data recorded in the U.S.", "date": "1980-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1980.EERL-80-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1980.EERL-80-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "8001.pdf", "url": "https://authors.library.caltech.edu/records/8hn54-vaw12/files/8001.pdf" }, "pub_year": "1980", "author_list": "Lee, David M.; Jennings, Paul C.; et el." }, { "id": "https://authors.library.caltech.edu/records/vgh77-csj17", "eprint_id": 26431, "eprint_status": "archive", "datestamp": "2023-08-19 11:57:02", "lastmod": "2024-01-13 05:31:11", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mason-Alfred-Barr", "name": { "family": "Mason", "given": "Alfred B" } } ] }, "title": "Some observations on the random response of linear and nonlinear dynamical systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1979: PB 290 808/AS\n\nAccepted Version - 7901.pdf
", "abstract": "First examined is the problem of obtaining the nonstationary stochastic response of a nonlinear system subject to deterministically modulated stationary Gaussian random excitation. An extension of the generalized method of equivalent linearization is used to obtain an approximation to this response. The accuracy of this approximate technique is investigated by means of Monte Carlo simulation.\n\nAttention is then turned to the first passage problem for the stationary response of a lightly damped linear oscillator excited by white noise. A method is developed to generate approximate values for the limiting decay rate of the corresponding first passage probability density. This method is extended so that an approximate first passage probability distribution may be calculated when the oscillator response is nonstationary. The accuracy of this approximate distribution is examined.\n\nAs a practical application, it is indicated how this technique may be used to determine an earthquake-like random process which generates a response spectrum consistent with given data. The accuracy and range of validity of the procedure are indicated by a simulation study.\n\nThe approximate solution of the first passage problem is combined with the equivalent linearization technique to yield a procedure for computing approximate first passage probabilities of a weakly nonlinear oscillator. The errors introduced by this procedure are investigated.", "date": "1979-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1979.EERL-79-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1979.EERL-79-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7901.pdf", "url": "https://authors.library.caltech.edu/records/vgh77-csj17/files/7901.pdf" }, "pub_year": "1979", "author_list": "Mason, Alfred B" }, { "id": "https://authors.library.caltech.edu/records/ecapr-neg97", "eprint_id": 26441, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:13", "lastmod": "2023-10-24 16:19:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } }, { "id": "Scott-R-F", "name": { "family": "Scott", "given": "Ronald F." } } ] }, "title": "An Investigation of the dynamic characteristics of an earth dam", "ispublished": "unpub", "full_text_status": "public", "note": "PB 288 878/AS", "abstract": "An investigation has been made to analyze observations of the effect of two earthquakes (with M L= 6. 3 and 4. 7) on Santa Felicia Dam, a rolled-fill embankment located in Southern California. The dam is 236.5 ft. high and 1,275 ft. long by 30 ft. wide at the crest. The purpose of the investigation is: (1) to study the nonlinear behavior of the dam during the two earthquakes, (2) to provide data on the in-plane dynamic shear moduli and damping factors for the materials of the dam during real earthquake conditions, and (3) to compare these properties with those previously available from laboratory investigations.\n\nFrom the recorded motions of the dam, amplification spectra were computed to indicate the natural frequencies of the dam and to estimate the relative contribution of different modes of vibrations. A comparison between these natural frequencies and those obtained by two elastic shear -beam models was made to obtain representative dam material properties. In addition, field wave-velocity measurements were carried out as a further check as well as to study the variation of shear wave velocity at various depths in the dam. The amplification spectra showed a predominant frequency of 1.45 Hz in the upstream/ downstream direction; in this direction the response was treated as that of a single-degree-of -freedom hysteretic structure. Three types of digital bandpass filtering of the crest and abutment records were used to enhance the hysteresis loops which show the relationship between the relative displacement of the crest with respect to the abutment and the absolute acceleration of the dam. A method is described which, using some of the existing elastic -response theories, enables the shear stresses and strains, and consequently the shear moduli, to be evaluated from the hysteresis loops. The equivalent viscous damping factors were calculated from the areas inside the hysteresis loops. The shear moduli and the damping factors were determined as functions of the induced strains in the dam. Finally, the shear moduli and damping factors obtained for the dam were compared with previously available laboratory data for sands and saturated clays.", "date": "1978-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1978.EERL-78-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1978.EERL-78-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7802.pdf", "url": "https://authors.library.caltech.edu/records/ecapr-neg97/files/7802.pdf" }, "pub_year": "1978", "author_list": "Abdel-Ghaffar, Ahmed Mansour and Scott, Ronald F." }, { "id": "https://authors.library.caltech.edu/records/d9xnn-e8n86", "eprint_id": 26394, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:02", "lastmod": "2024-01-13 05:30:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beck-J-L", "name": { "family": "Beck", "given": "James L." } } ] }, "title": "Determining models of structures from earthquake records", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1979: PB 288 806/AS\n\nAccepted Version - 7801.pdf
", "abstract": "The problem of determining linear models of structures from seismic response data is studied using ideas from the theory of system identification. The investigation employs a general formulation called the output-error approach, in which optimal estimates of the model parameters are obtained by minimizing a selected measure-of-fit between the responses of the structure and the model. The question of whether the parameters can be determined uniquely and reliably in this way is studied for a general class of linear structural models. Because earthquake records are normally available from only a small number of locations in a structure, and because of measurement noise, it is shown that it is necessary in practice to estimate parameters of the dominant modes in the records, rather than the stiffness and damping matrices.\n\nTwo output-error techniques are investigated. Tests of the first, an optimal filter method, show that its advantages are offset by weaknesses which make it unsatisfactory for application to seismic response. A new technique, called the modal minimization method, is developed to overcome these difficulties. It is a reliable and efficient method to determine the optimal estimates of modal parameters for linear structural models.\n\nThe modal minimization method is applied to two multi- story buildings that experienced the 1971 San Fernando earthquake. New information is obtained concerning the properties of the higher modes of the taller building and more reliable estimates of the properties of the fundamental modes of both structures are found. The time-varying character of the equivalent linear parameters is also studied for both buildings. It is shown for the two buildings examined that the optimal, time-invariant, linear models with a small number of modes can reproduce the strong-motion records much better than had been supposed from previous work using less systematic techniques.", "date": "1978-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1978.EERL-78-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1978.EERL-78-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7801.pdf", "url": "https://authors.library.caltech.edu/records/d9xnn-e8n86/files/7801.pdf" }, "pub_year": "1978", "author_list": "Beck, James L." }, { "id": "https://authors.library.caltech.edu/records/h2zq1-f2s15", "eprint_id": 26536, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:23", "lastmod": "2023-10-24 16:22:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Helmberger-D-V", "name": { "family": "Helmberger", "given": "Donald V." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Strong ground motion : N.S.F. Seminar-Workshop Proceedings", "ispublished": "unpub", "full_text_status": "public", "abstract": "PREFACE\n\nThe volume represents the Proceedings of a small Seminar - Workshop held at the Inn at Rancho Santa Fe, near San Diego, in February 1978. The meeting was conceived in response to a growing awareness of the mutual interest in research workers in seismology and earthquake engineers in the records of strong ground motion. The Seminar - Workshop was partly sponsored by the geophysical and earthquake engineering research programs within the National Science Foundation, and was jointly organized by Donald V. Helmberger of the Seismological Laboratory and Paul C. Jennings of the Earthquake Engineering Research Laboratory, of the California Institute of Technology. The organizers wish to take this opportunity to acknowledge the helpful assistance of Thomas Hanks, Leonard Johnson and S. C. Liu.\n\nINTRODUCTION\n\nThe strong ground motion near the source of a major earthquake determines the forces which endanger buildings and other works of construction, and at. the same time is the most detailed clue available concerning the source mechanism of the earthquake. The records obtained of strong ground motion are, therefore, of interest to both seismologists and earthquake engineers, although the two disciplines have tended to look at the records quite differently, and to pursue their examinations separately. In the past few years, however, there has been a growing awareness of the mutual interest in strong ground motion and a number of individuals believed there would be considerable value in convening a small group of seismologists and earthquake engineers who are doing research on strong ground motion for a Seminar Workshop. It was envisioned that a Seminar - Workshop would be a useful means for scientists and engineers to discuss their mutual interests and problems, and to hear and discuss those areas where their interests and viewpoints are different.\nThere are many fundamental questions in seismology and earthquake engineering which focus attention on the nature of strong ground motion. From the seismological viewpoint, the records of strong ground motion provide the best source of high frequency information on the way that energy is released during the rupture process. Additionally, strong motion data has the capability of providing a major means for determining the nature of the source mechanisms in great earthquakes. The extent of the source mechanism, the stress drop and other parameters of the source, and the range of complexity of source mechanisms are all capable of being studied through strong-motion records. From the engineering viewpoint the central problems are the characterization of strong ground motion for the purpose of establishing design criteria and the determination of the nature of the shaking in the near-field of major and great earthquakes. These problems are faced in the design of almost every major facility in the more seismic areas of the country and there is not yet a consensus or how to deal with them. To resolve these important practical problems requires a much increased understanding of strong ground motion. A problem of mutual interest to both seismologists and earthquake engineers is the way the earthquake motion is altered as it propagates away from the source. Seismologists have examined this problem by studies of radiation patterns under idealized conditions and by calculating the effects of regional geology on ground motions of periods of one second and more. Under similar assumptions, earthquake engineers have calculated the effects of surficial soil deposits on strong ground motions of shorter period.\nAt a few institutions significant interaction between seismologists and earthquake engineers has developed, but there is clearly a benefit to be gained. by much more communication between the two disciplines; it was the intent of the Seminar - Workshop to accelerate this communication. It was also hoped that a number of areas of mutual interest and research need could be identified.\nThis report, which contains extended abstracts of the invited papers, represents the Proceedings and the Seminar - Workshop. The papers and the discussions at the conference were grouped around three major areas.\n(1) Characterization and parameterization of strong ground motions.\n(2) Simulation and modeling of strong motions: deterministic and statistical.\n(3) Source mechanisms and estimation of strong motion for great earthquakes.\nThe invited papers are followed by a brief discussion of the directions of future research.\n\nD. V. Helmberger\nP. C. Jennings", "date": "1978-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL.1978.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL.1978.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "NSFStrongMotion_1978.pdf", "url": "https://authors.library.caltech.edu/records/h2zq1-f2s15/files/NSFStrongMotion_1978.pdf" }, "pub_year": "1978", "author_list": "Helmberger, Donald V. and Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/0g7ew-ezy11", "eprint_id": 26430, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:08", "lastmod": "2023-10-24 16:19:16", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Psycharis-I-N", "name": { "family": "Psycharis", "given": "Ioannis N." } } ] }, "title": "The Salonica (Thessaloniki) earthquake of June 20, 1978", "ispublished": "unpub", "full_text_status": "public", "note": "PB 290 120/AS", "abstract": "The 6.5 magnitude Salonica earthquake of June 20, 1978 is an earthquake of major interest from the engineering point of view, since it occurred near a city of 700,000 inhabitants. In general, the damage was not extensive and modern buildings performed quite well during the earthquake, while some old ones suffered severe damage.\n\nThe author was on vacation in Athens at the time of the earthquake and visited Salonica on June 23rd. As the intention of this visit was to make a general survey of the affected area, detailed descriptions of the engineering features of the earthquake and the building damage are not included in this report.", "date": "1978-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1978.EERL-78-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1978.EERL-78-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7803.pdf", "url": "https://authors.library.caltech.edu/records/0g7ew-ezy11/files/7803.pdf" }, "pub_year": "1978", "author_list": "Psycharis, Ioannis N." }, { "id": "https://authors.library.caltech.edu/records/m8dz7-5aa04", "eprint_id": 26531, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:18", "lastmod": "2023-10-24 16:22:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "Strong-motion earthquake instrument arrays : proceedings of the International Workshop on Strong-Motion Earthquake Instrument Arrays, May 2-5, 1978, Honolulu, Hawaii", "ispublished": "unpub", "full_text_status": "public", "note": "Approved for deposit by W.D. Iwan, 7/2002", "abstract": "The International Workshop on Strong-Motion Earthquake Instrument Arrays was held May 2-5, 1978 at the East-West Center, Honolulu, Hawaii. The Workshop was organized by a Steering Committee appointed by the International Association for Earthquake Engineering. This volume is the product of the combined efforts of those in attendance.\n\nThe goal of the Workshop was to develop a workable plan for the possible future deployment of dense strong-motion earthquake instrument arrays with primary emphasis on ground motion studies. Three potential areas of array application were considered; source mechanism studies, wave propagation studies and studies of local effects. In order to achieve its stated goal, the Workshop was organized into five working subgroups. The areas covered by the subgroups were: favorable array locations, array design for source mechanism and wave propagation studies, array design for local effects studies, array construction and operation, and implementation. The reports of the individual subgroups are incorporated as chapters in this volume.\n\nExperts in earthquake engineering and seismology were invited from all over the world to participate in the Workshop. Those individuals with specific expertise necessary for the deliberations of a particular subgroup were invited to serve as working members of that subgroup. In addition, a number of individuals were invited as Workshop observers in order to insure a balanced geographical and technical representation.", "date": "1978-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:EERL.1978.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:EERL.1978.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Iwan_1978.pdf", "url": "https://authors.library.caltech.edu/records/m8dz7-5aa04/files/Iwan_1978.pdf" }, "pub_year": "1978", "author_list": "Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/z8t55-c7t08", "eprint_id": 26351, "eprint_status": "archive", "datestamp": "2023-08-19 10:25:58", "lastmod": "2023-10-24 16:16:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "An analysis of the dynamic characteristics of a suspension bridge by ambient vibration measurements", "ispublished": "unpub", "full_text_status": "public", "note": "PB 275 063/AS", "abstract": "Extensive experimental investigations were conducted on the Vincent-Thomas Suspension Bridge at Los Angeles Harbor to determine natural frequencies and mode shapes of vertical, torsional and lateral vibrations of the structure. These ambient vibration tests involved the simultaneous measurements of both vertical and lateral vibrational motions caused by traffic. Measurements were made at selected points on different cross sections of the stiffening structure. Comparison with previously computed mode shapes and frequencies shows good agreement with the experimental results, thus confirming both the accuracy of the experimental determination and the reliability of the method of computation.", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL-77-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL-77-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7701.pdf", "url": "https://authors.library.caltech.edu/records/z8t55-c7t08/files/7701.pdf" }, "pub_year": "1977", "author_list": "Abdel-Ghaffar, Ahmed Mansour and Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/xccqe-7g909", "eprint_id": 26506, "eprint_status": "archive", "datestamp": "2023-08-19 10:26:25", "lastmod": "2023-10-24 16:21:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Morrison-P", "name": { "family": "Morrison", "given": "Paul" } }, { "id": "Maley-R", "name": { "family": "Maley", "given": "Richard" } }, { "id": "Brady-G", "name": { "family": "Brady", "given": "Gerald" } }, { "id": "Porcella-R", "name": { "family": "Porcella", "given": "Ronald" } } ] }, "title": "Earthquake recordings on or near Dams", "ispublished": "unpub", "full_text_status": "public", "note": "United States Committee on Large Dams. Committee on Earthquakes (G.W. Housner, Chairman) Panel on Earthquake Recordings at Dams (P. Morrison, Ch.)", "abstract": "This report presents data on earthquake recordings made on or near dams. The serious consequences of failure makes it imperative that dams in seismic regions be designed to resist earthquake shaking safely and economically. To achieve this, designers of dams must be provided with information about those dams that have been subjected to strong ground shaking, with or without damage. The most valuable of such information is provided by seismic recordings made on or near dams during strong shaking, as these show the nature of the earthquake shaking. Unfortunately there exist relatively few such recordings because only few dams are instrumented for this purpose. This report provides a collection of seismic records, ranging from very strong shaking to moderate shaking, which should be informative to engineers who design dams. There have been other cases where dams have been damaged by earthquakes but the shaking was not recorded by instruments. It is hoped that, in the future, all instances of earthquake damage to dams, or earthquake recordings on or near dams, will be described in publications so that the information is available to dam designers in all parts of the world.\n\nEarlier reports issued by the Committee on Earthquakes are \"Seismic Instrumentation of Dams\" by B. A. Bolt and D. E. Hudson, April 1975; and \"Evaluation of Seismicity at U.S. Reservoirs\" by W. Daly, W. Judd, and R. Meade, May 1977.", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL.1977.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL.1977.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "morrison_1977.pdf", "url": "https://authors.library.caltech.edu/records/xccqe-7g909/files/morrison_1977.pdf" }, "pub_year": "1977", "author_list": "Morrison, Paul; Maley, Richard; et el." }, { "id": "https://authors.library.caltech.edu/records/xwmjk-1m418", "eprint_id": 26502, "eprint_status": "archive", "datestamp": "2023-08-19 10:26:19", "lastmod": "2023-10-24 16:21:37", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Daly-W", "name": { "family": "Daly", "given": "W" } }, { "id": "Judd-W", "name": { "family": "Judd", "given": "W" } }, { "id": "Meade-R", "name": { "family": "Meade", "given": "R" } } ] }, "title": "Evaluation of seismicity at U.S. reservoirs", "ispublished": "unpub", "full_text_status": "public", "note": "From title page: United States Committee on Large Dams. Committee on Earthquakes. (George W. Housner, Chairman) Panel on Evaluation of Seismicity (W. Judd, Chairman)", "abstract": "This report presents data relevant to the occurrence of reservoir\ufdd3associated earthquakes. The possible occurrence of earthquakes, presumably associated with reservoir loading, that cause intense shaking at a dam\ufdd3site strong enough to damage the dam, as in the case of Koyna, India and Hsinfengkiang, Peoples Republic of China, poses a problem to the designers of dams. The Committee on Earthquakes is studying the problem and this report is the first that addresses the subject of the occurrence of earthquakes near dams. The Committee has issued an earlier report \"Seismic Instrumentation of Dams\" by Bruce A. Bolt and Donald E. Hudson, April, 1975, which also appeared in the Journal of the Geotechnical Division, American Society of Civil Engineers, GT11, November 1975.\n\nThe Committee on Earthquakes collects, analyses and publishes data relevant to earthquake hazards and the design of dams, and identifies areas where additional research is needed. The project for preparing this report received partial support from the National Science Foundation. Any findings, opinions, conclusions or recommendations presented in this report are those of the authors and not of the National Science Foundation.", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL.1977.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL.1977.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Daly_1977.pdf", "url": "https://authors.library.caltech.edu/records/xwmjk-1m418/files/Daly_1977.pdf" }, "pub_year": "1977", "author_list": "Daly, W; Judd, W; et el." }, { "id": "https://authors.library.caltech.edu/records/84swf-8k115", "eprint_id": 26352, "eprint_status": "archive", "datestamp": "2023-08-19 10:26:03", "lastmod": "2023-10-24 16:16:37", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } } ] }, "title": "Studies on the effect of differential motions of two foundations upon the response of the superstructure of a bridge", "ispublished": "unpub", "full_text_status": "public", "note": "PB 271 095/AS", "abstract": "This report contains two studies that were made of the effects of differential motion of the foundations upon the response of the super structure of a bridge. The first study deals with the dynamic response of a \"1ong beam\" model of a bridge to both steady-state and random excitations applied at the supports. The study has been simplified by considering a long shear beam, simply supported at two ends; this beam is subjected to two end excitations in the form of ground displacements. Harmonic excitations, differing in phase at the ends, were considered in the frequency domain by analyzing the steady state vibrations and calculating the displacement amplitudes at specific points on the beam. The energy content of the system has been presented, and the correlation between the two end excitations has been considered. For the random excitations, the analysis has been made in the time domain; two different cases of random motions have been considered.\n\nThe second study develops a method to analyze the dynamic soilbridge interaction of a simple two-dimensional bridge model erected on an elastic half-space, with the input motion in the form of incident plane SH-waves. The bridge model consists of an elastic shear girder supported by two rigid abutments and rigid foundations which have a circular cross section and which are welded to the half-space. Finally, the dynamic response of the bridge and the effect of the radiative damping in the half-space on the interaction of the bridge are also studied.", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL-77-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL-77-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7702.pdf", "url": "https://authors.library.caltech.edu/records/84swf-8k115/files/7702.pdf" }, "pub_year": "1977", "author_list": "Abdel-Ghaffar, Ahmed Mansour" }, { "id": "https://authors.library.caltech.edu/records/p8461-a0c92", "eprint_id": 26439, "eprint_status": "archive", "datestamp": "2023-08-19 10:26:14", "lastmod": "2023-10-24 16:19:34", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Earthquake design criteria for structures", "ispublished": "unpub", "full_text_status": "public", "note": "PB 276 502/AS", "abstract": "The earthquake resistant design of structures plays an important role in seismic regions both from the point of view of public safety and from the point of view of economical construction. Since construction is at a rate of approximately $15 billion per year in the seismic regions of the United States, unnecessary expenditures on earthquake protection could be very costly but, on the other hand, very costly damage could result if a city has inadequate earthquake protection and is shaken by a strong earthquake. The loss of life in an inadequately protected city could be very large, as evidenced by the reported 700,000 casualties inflicted by the Tang-Shan, China earthquake of 28 July 1976. The engineering profession has the technical responsibility for the safe and economical protection against earthquakes. The prime consideration in achieving this protection is the formulation of proper earthquake design criteria. Because the time and place of occurrence of future earthquakes cannot be foretold, the earthquake forces to which a structure will be subjected during its lifetime can not be specified at the time it is being designed and, therefore, consideration mast be given to the desired performance of the structure if it should be subjected to weak earthquakes which have a relatively high probability of occurrence, or to very strong earthquakes which have relatively low probability of occurrence. The earthquake design criteria must then be formulated so that the building is, indeed, capable of the desired performance, and this formulation should be the responsibility of the project engineer.", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL-77-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL-77-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7706.pdf", "url": "https://authors.library.caltech.edu/records/p8461-a0c92/files/7706.pdf" }, "pub_year": "1977", "author_list": "Housner, George W. and Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/s798f-y2b36", "eprint_id": 26437, "eprint_status": "archive", "datestamp": "2023-08-19 10:26:09", "lastmod": "2023-10-24 16:19:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } } ] }, "title": "Engineering data and analyses of the Whittier, California earthquake of January 1, 1976", "ispublished": "unpub", "full_text_status": "public", "note": "PB 283 750/AS", "abstract": "A magnitude 4.2 earthquake occurred near Whittier, California on January 1, 1976 at 09:20 Pacific Standard time. The shock was centered at 33.58N (Lat.) and 117.53W (Long.) in the Puente Hills of Los Angeles County. The ground shaking was recorded within a 14 Km (8.7 miles) radius of the instrumentally determined epicenter, and eleven strong-motion accelerograph records were obtained on 70 mm film from SMA-1 accelerographs operated as part of the U.S.G.S. Seismic Engineering Branch network. Although of relatively small magnitude, the earthquake did produce peak ground accelerations as high as 187% g, which merit an engineering analysis. The locations of the strong-motion accelerograph stations at the time of the earthquake are shown in Fig. 1. The eleven records were obtained from different structures as follows: (1) three records from a ten-story modern reinforced-concrete building in Whittier, (2) three records from the Carbon Canyon earth-dam site, (3) two records from the Brea earth-dam site, (4) two records from the Diemer Filtration Plant, and finally (5) one record from the Orange County Reservoir. Instruments located at Whittier Dam (16.4 Km from the instrumental epicenter) and at Puddingstone Dam (15.0 Km from the epicenter) were operational, but were not triggered by the event (Etheredge and Nielson, Ref. 1).", "date": "1977-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1977.EERL-77-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1977.EERL-77-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7705.pdf", "url": "https://authors.library.caltech.edu/records/s798f-y2b36/files/7705.pdf" }, "pub_year": "1977", "author_list": "Abdel-Ghaffar, Ahmed Mansour" }, { "id": "https://authors.library.caltech.edu/records/z5411-f4w19", "eprint_id": 26345, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:28", "lastmod": "2023-10-23 20:59:44", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms index volume", "ispublished": "unpub", "full_text_status": "public", "note": "PB 260 929/AS", "abstract": "The purpose of the present report is to supply cross-referenced index lists which will facilitate the location of earthquake records from particular earthquakes and sites. These lists and the accompanying maps will also serve as a complete description of the location of all stations.\n\nA secondary purpose of the report is to collect in one place various corrections, addenda, and supplementary information which should assist research workers in making use of the data.", "date": "1976-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1976.EERL-76-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1976.EERL-76-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7602.pdf", "url": "https://authors.library.caltech.edu/records/z5411-f4w19/files/7602.pdf" }, "pub_year": "1976" }, { "id": "https://authors.library.caltech.edu/records/p0hnx-ne957", "eprint_id": 26427, "eprint_status": "archive", "datestamp": "2023-08-19 09:53:22", "lastmod": "2023-10-24 16:19:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abdel-Ghaffar-A-M", "name": { "family": "Abdel-Ghaffar", "given": "Ahmed Mansour" } } ] }, "title": "Dynamic analyses of suspension bridge structures", "ispublished": "unpub", "full_text_status": "public", "note": "PB 258 744/AS", "abstract": "A method of dynamic analysis for vertical, torsional and lateral free vibrations of suspension bridges has been developed that is based on linearized theory and the finite-element approach. The method involves two distinct steps: (1) specification of the potential and kinetic energies of the vibrating members of the continuous structure, leading to derivation of the equations of motion by Hamilton's Principle, (2) use of the finite-element technique to: (a) discretize the structure into equivalent systems of finite elements, (b) select the displacement model most closely approximating the real case, (c) derive element and assemblage stiffness and inertia properties, and finally (d) form the matrix equations of motion and the resulting eigenvalue problems. The stiffness and inertia properties are evaluated by expressing the potential and kinetic energies of the element (or the assemblage) in terms of nodal displacements. Detailed numerical examples are presented to illustrate the applicability and effectiveness of the analysis and to investigate the dynamic characteristics of suspension bridges with widely different properties. This method eliminates the need to solve transcendental frequency equations, simplifies the determination of the energy stored in different members of the bridge, and represents a simple, fast and accurate tool for calculating the natural frequencies and modes of vibration by means of a digital computer. The method is illustrated by calculating the modes and frequencies of a bridge and comparing them with the measured frequencies.", "date": "1976-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1976.EERL-76-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1976.EERL-76-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7601.pdf", "url": "https://authors.library.caltech.edu/records/p0hnx-ne957/files/7601.pdf" }, "pub_year": "1976", "author_list": "Abdel-Ghaffar, Ahmed Mansour" }, { "id": "https://authors.library.caltech.edu/records/e94xa-wf428", "eprint_id": 26429, "eprint_status": "archive", "datestamp": "2023-08-19 09:53:27", "lastmod": "2023-10-24 16:19:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spanos-P-T-D", "name": { "family": "Spanos", "given": "P-T. D" } } ] }, "title": "Linearization techniques for non-linear dynamical systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1977: PB 266 083/AS", "abstract": "This dissertation is concerned with the application of linearization techniques to the study of the response of non-linear dynamical systems subjected to periodic and random excitations.\n\nA general method for generating an approximate solution of a multi-degree-of-freedom non-linear dynamical system is presented. This method relies on solving an optimum equivalent linear substitute of the original system.\n\nThe applicability of the method for determination of the amplitudes and phases of the approximate steady-state solution of a multi-degree-of-freedom non-linear system under harmonic monofrequency excitation is considered. The implementation of the method for several special classes of non-linear functions is discussed in detail. In addition, the manner in which the method may be applied to generate an approximate solution for the covariance matrix of the stationary random response of a multi- degree- of freedom dynamical system subjected to stationary Gaussian excitation is outlined.\n\nThe potential of the method to treat transient solutions of non-linear systems is indicated in the context of the non-stationary response of a lightly damped and weakly non-linear oscillator subjected to monofrequency harmonic or to a Gaussian white noise disturbance. For both classes of excitation the method produces a first-order differential equation governing the response amplitude. The results pertinent to the harmonically excited oscillator are compared with existing solutions. A non-stationary solution of the Fokker-Planck equation associated with the stochastic differential equation governing the response amplitude of the randomly excited oscillator is accomplished by perturbation techniques; the stationary solution is determined without making any approximation in the Fokker-Planck equation.\n\nThe new method for transient response is applied to the random response of a Duffing Oscillator and a Hysteretic System. The solution for the Duffing Oscillator is compared with data obtained by a Monte Carlo study.", "date": "1976-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1976.EERL-76-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1976.EERL-76-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7604.pdf", "url": "https://authors.library.caltech.edu/records/e94xa-wf428/files/7604.pdf" }, "pub_year": "1976", "author_list": "Spanos, P-T. D" }, { "id": "https://authors.library.caltech.edu/records/x4d96-hqs33", "eprint_id": 26290, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:23", "lastmod": "2023-10-23 20:58:01", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part T - Accelerograms IT274 through IT293", "ispublished": "unpub", "full_text_status": "public", "keywords": "IT274 IT275 IT276 IT277 IT278 IT279 IT280 IT281 IT282 IT283 IT284 IT285 IT286 IT287 IT288 IT289 IT290 IT291 IT292 IT293\n38.001 38.003 38.004 40.001.1 40.001.2 40.001.3 40.001.4 40.001.5 40.001.6 40.001.7 40.001.8 40.001.9 42.001 51.002 53.001 54.005 55.003 55.004 55.005 66.009", "note": "PB 241 943/AS", "abstract": "This issue contains records from the El Centro, California, site in the basement of the Imperial Valley Irrigation District substation, from 1938 to 1966 including nine groups of aftershocks of the May 18, 1940 Imperial Valley earthquake.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-25", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-25", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7325.pdf", "url": "https://authors.library.caltech.edu/records/x4d96-hqs33/files/7325.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/m0p6f-tbz14", "eprint_id": 26337, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:25", "lastmod": "2023-10-23 20:59:26", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part U - Accelerograms IIU294 through IIU313", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIU294 IIU295 IIU296 IIU297 IIU298 IIU299 IIU294 IIU295 IIU296 IIU297 IIU298 IIU299 IIU300 IIU301 IIU302 IIU303 IIU304 IIU305 IIU306 IIU307 IIU308 IIU309 IIU310 IIU311 IIU312 IIU313", "note": "PB 242 949/AS", "abstract": "This issue, Volume II, Part U, Report No. EERL 75-51, contains California records from Ferndale, Santa Barbara, Hollister, Tehachapi, San Jose and Taft, together with records from Helena, Montana, and Seattle, Washington, during the years 1934 to 1967. Further records from some of these sites have appeared in other parts of the series.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-51", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-51", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7551.pdf", "url": "https://authors.library.caltech.edu/records/m0p6f-tbz14/files/7551.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/jrks5-2j951", "eprint_id": 26340, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:51", "lastmod": "2023-10-23 20:59:33", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Parts W and Y - Accelerograms IIW334 to IIW336, IIW338, IIW339, IIW342 to IIW345, and IIY370 to IIY381", "ispublished": "unpub", "full_text_status": "public", "keywords": "IW334 IW335 IW336 IW338 IW339 IW342 IW343 IW344 IW345 IY370 IY371 IY372 IY373 IY374 IY375 IY376 IY377 IY378 IY379 IY380 IY381", "note": "PB 243 492/AS", "abstract": "The records analyzed in this report, Volume III, Parts W and Y, are the corrected accelerogram records contained in Volume II, Parts W and Y, Report No. EERL 75-53, and appeared in their uncorrected form in Volume I, Part W, Report No. EERL 73-28, and Volume I, Part Y, Report No. EERL 73-30.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-83", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-83", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7583.pdf", "url": "https://authors.library.caltech.edu/records/jrks5-2j951/files/7583.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/vmk5v-1y747", "eprint_id": 26288, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:07", "lastmod": "2023-10-23 20:57:56", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part Y - Accelerograms IY370 through IY381", "ispublished": "unpub", "full_text_status": "public", "keywords": "IY370 IY371 IY372 IY373 IY374 IY375 IY376 IY377 IY378 IY379 IY380 IY381 68.099 68.103 68.080 68.089 68.100 68.055 68.104 68.106 68.072 68.026 68.071 68.025", "note": "PB 242 947/AS", "abstract": "This issue, Part Y, is the final part of a series initiated in July, 1969, and contains data from the Borrego Mountain, California, earthquake of April 8, 1968, including two records each from the JPL Building in Pasadena and the Hollywood Storage Building in Los Angeles and single records from Colton, Santa Ana, Terminal Island in Long Beach, the Millikan Library and Athenaeum at Caltech in Pasadena, the Edison Building at 601 W. 5th St. and the Subway Terminal, both in Los Angeles, and Vernon. Other records from El Centro, San Diego and San Onofre were included in Parts A and B.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-30", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-30", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7330.pdf", "url": "https://authors.library.caltech.edu/records/vmk5v-1y747/files/7330.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/yhvfw-9gm83", "eprint_id": 26344, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:22", "lastmod": "2023-10-23 20:59:41", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part V - Accelerograms IIV314 through IIV333", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIV314 IIV315 IIV316 IIV317 IIV318 IIV319 IIV320 IIV321 IIV322 IIV323 IIV324 IIV325 IIV326 IIV327 IIV328 IIV329\nIIV330 IIV331 IIV332 IIV333", "note": "PB 242 951/AS", "abstract": "The records analyzed in this report, Volume III, Part V, are the corrected accelerogram records of Volume II,\nPart V, Report No. EERL 75-52, and appeared in their uncorrected form in Volume I, Part V, Report No. EERL 73-27.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-82", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-82", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7582.pdf", "url": "https://authors.library.caltech.edu/records/yhvfw-9gm83/files/7582.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/3tch9-hdf36", "eprint_id": 26285, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:45", "lastmod": "2023-10-23 20:57:49", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part U - Accelerograms IU294 through IU313", "ispublished": "unpub", "full_text_status": "public", "keywords": "IU294 IU295 IU296 IU297 IU298 IU299 IU300 IU301 IU302 IU303 IU304 IU305 IU306 IU307 IU308 IU309 IU310 IU311 IU312 IU313 34.001 35.002 35.004 35.003 37.001 41.002 41.003 49.001 52.007 52.008 52.010 54.002 55.002 60.001 60.002 61.002 65.003 66.006 67.001 67.006", "note": "PB 242 252/AS", "abstract": "This issue contains California records from Ferndale, Santa Barbara, Hollister, Tehachapi, San Jose, and Taft, together with records from Helena, Montana, and Seattle, Washington, during the years 1934 to 1967. Further records from some of these sites have appeared in other parts of the series.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-26", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-26", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7326.pdf", "url": "https://authors.library.caltech.edu/records/3tch9-hdf36/files/7326.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/j7zd9-1dm34", "eprint_id": 26426, "eprint_status": "archive", "datestamp": "2023-08-19 09:16:44", "lastmod": "2023-10-24 16:19:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Foutch-Douglas-Allen", "name": { "family": "Foutch", "given": "Douglas Allen" } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Dynamic responses of six multistory buildings during the San Fernando earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "PB 248 144/AS", "abstract": "The development of optimal methods of earthquake resistant design depends on a knowledge of how the ground shakes and how real buildings oscillate during earthquakes. The San Fernando earthquake of February 9, 1971 occurred in a region well instrumented to record ground shaking and building vibration and, as a consequence, many records were obtained that illustrate the engineering features of earthquake ground motion and its effects. The magnitude 6. 5 earthquake was centered on the northern edge of the Los Angeles Metropolitan area. Although the shock was not a great earthquake in seismological terms, it produced very strong ground shaking and, therefore, was an important event for engineers. The resulting damage, estimated at over $500 million, provided valuable engineering lessons concerning the design of buildings, bridges, darns, and other facilities; and numerous special studies of the effects of the San Fernando earthquake on various structures have been published. 1-6 The shock triggered 272 accelerographs, and 241 accelerograms were recorded. These records provide valuable information about the characteristics of strong ground motions and structural responses, and make it possible to evaluate the measured performance of modern buildings during strong earthquakes.\n\nThe San Fernando earthquake was of special importance to structural engineers since it provided the first sample of recorded responses of modern multistoried buildings to strong earthquake motions. The responses of more than 50 buildings were measured, most of which were located in the city of Los Angeles, and had accelerographs in the basement, at mid-height, and on the roof in accordance with building code requirements.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7502.pdf", "url": "https://authors.library.caltech.edu/records/j7zd9-1dm34/files/7502.pdf" }, "pub_year": "1975", "author_list": "Foutch, Douglas Allen; Housner, George W.; et el." }, { "id": "https://authors.library.caltech.edu/records/y3rdh-53w49", "eprint_id": 26342, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:06", "lastmod": "2023-10-23 20:59:37", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts T and U - Accelerograms IIT274 to IIT293 and IIU294 to IIU313", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIT274 IIT275 IIT276 IIT277 IIT278 IIT279 IIT280 IIT281 IIT282 IIT283 IIT284 IIT285 IIT286 IIT287 IIT288 IIT289 IIT290 IIT291 IIT292 IIT293 IIU294 IIU295 IIU296 IIU297 IIU298 IIU299 IIU300 IIU301 IIU302 IIU303 IIU304 IIU305 IIU306 IIU307 IIU308 IIU309 IIU310 IIU311 IIU312 IIU313", "note": "PB 243 493/AS", "abstract": "The corrected records analyzed in this report, Volume IV, Parts T and U, appeared in Volume II, Part T, Report No. EERL 75-50, and Volume II, Part U, Report No. EERL 75-51. Their uncorrected versions were published in Volume I, Part T, Report No. EERL 73-25, and Volume I, Part U, Report No. EERL 73-26.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-100", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-100", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "75100.pdf", "url": "https://authors.library.caltech.edu/records/y3rdh-53w49/files/75100.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/ewd6y-ryr07", "eprint_id": 26307, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:46", "lastmod": "2023-10-23 20:58:38", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part V - Accelerograms IV314 through IV333", "ispublished": "unpub", "full_text_status": "public", "keywords": "IV314 IV315 IV316 IV317 IV318 IV319 IV320 IV321 IV322 IV323 IV324 IV325 IV326 IV327 IV328 IV329 IV330 IV331 IV332 IV333 33.002 33.003 41.004 41.005 52.004 52.012 57.001 57.011 57.014 57.015 57.016 57.017 57.020 57.021 57.022 57.023 62.001 65.006 66.010 67.008", "note": "PB 243 483/AS", "abstract": "This issue contains California records from the Los Angeles and Long Beach areas, San Luis Obispo, various buildings in the San Francisco Bay area, Port Hueneme, Eureka, Castaic, and Sacramento during the years 1933 to 1967. Further records from some of these sites have appeared in other parts of the series.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-27", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-27", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7327.pdf", "url": "https://authors.library.caltech.edu/records/ewd6y-ryr07/files/7327.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/67v6p-7pm61", "eprint_id": 26339, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:40", "lastmod": "2023-10-23 20:59:31", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Parts W and Y - Accelerograms IIW334 to IIW336, IIW338, IIW339, IIW342 to IIW345, and IIY370...", "ispublished": "unpub", "full_text_status": "public", "keywords": "IW334 IW335 IW336 IW338 IW339 IW342 IW343 IW344 IW345 IY370 IY371 IY372 IY373 IY374 IY375 IY376 IY377 IY378 IY379 IY380 IY381", "note": "PB 243 749", "abstract": "This issue, Volume II, Parts W and Y, Report No. EERL 75-53, is the last of this series of reports, and contains records from two Southern California earthquakes: Lytle Creek, September 12, 1970, and Borrego Mountain, April 8, 1968.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-53", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-53", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7553.pdf", "url": "https://authors.library.caltech.edu/records/67v6p-7pm61/files/7553.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/rxj6d-dew37", "eprint_id": 26289, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:15", "lastmod": "2023-10-23 20:57:58", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part W - Accelerograms IW334 through IW 354", "ispublished": "unpub", "full_text_status": "public", "note": "PB 243 483/AS IW334 IW335 IW336 IW337 IW338 IW339 IW340 IW341 IW342 IW343 IW344 IW345 IW346 IW347 IW348 IW349 IW350 IW351 IW352 IW353 IW354 70.002 70.011 70.004 70.007 70.010 70.009 70.008 70.006 70.038 70.003 70.039 70.040 70.005 70.012 70.013 70.015 70.016 70.017 70.018 70.019 70.020", "abstract": "This issue, Part W, contains data from the Lytle Creek, California, earthquake of September 12, 1970, and includes three records each from the buildings at 945 Tiverton and 120 N. Robertson in Los Angeles; two records each from the Hollywood Storage Building in Los Angeles, J. P. L. and the Millikan Library in Pasadena, and the Cedar Springs CWR site; and single records from Wrightwood, Devil's Canyon and the Hall of Records in San Bernardino, Colton, Puddingstone Dam in San Dimas, Santa Anita Dam in Arcadia, and the Old Ridge Route in Castaic.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-28", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-28", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7328.pdf", "url": "https://authors.library.caltech.edu/records/rxj6d-dew37/files/7328.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/nzgk5-2rh14", "eprint_id": 26327, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:47", "lastmod": "2023-10-23 20:59:16", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - integrated ground velocity and displacement curves; Part T - Accelerograms IT274 through IT293", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIT274 IIT275 IIT276 IIT277 IIT278 IIT279 IIT280 IIT281 IIT282 IIT283 IIT284 IIT285 IIT286 IIT287 IIT288 IIT289 IIT290 IIT291 IIT292 IIT293", "note": "PB 242 433/AS", "abstract": "This issue, Volume II, Part T, Report No. EERL 75-50, contains records from the El Centro, California, site in the basement of the Imperial Valley Irrigation District substation, from 1938 to 1966 including nine groups of aftershocks of the May 18, 1940, Imperial Valley earthquake.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-50", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-50", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7550.pdf", "url": "https://authors.library.caltech.edu/records/nzgk5-2rh14/files/7550.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/gk7yw-0gn03", "eprint_id": 26253, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:43", "lastmod": "2023-10-23 20:57:15", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part T - Accelerograms IIT274 through IIT293", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIT274 IIT275 IIT276 IIT277 IIT278 IIT279 IIT280 IIT281 IIT282 IIT283 IIT284 IIT285 IIT286 IIT287 IIT288 IIT289 IIT290 IIT291 IIT292 IIT293", "note": "PB 243 698/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital printout of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Part T, are the corrected accelerogram records contained in Volume II, Part T, Report No. EERL 75-50, and appeared in their uncorrected form in Volume I, Part T, Report No. EERL 73-25.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-80", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-80", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7580.pdf", "url": "https://authors.library.caltech.edu/records/gk7yw-0gn03/files/eerl7580.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/jr717-ynm27", "eprint_id": 26295, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:03", "lastmod": "2023-10-23 20:58:11", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part X - Accelerograms IX355 through IX369", "ispublished": "unpub", "full_text_status": "public", "keywords": "IX355 IX356 IX357 IX358 IX359 IX360 IX361 IX362 IX363 IX364 IX365 IX366 IX367 IX368 IX369 70.021 70.022 70.023 70.024 70.025 70.026 70.029 70.030 70.031 70.032 70.033 70.034 70.035 70.036 70.037", "note": "PB 243 594/AS", "abstract": "This issue, Part X, contains data from the Lytle Creek, California, earthquake of September 12, 1970, and includes three records each from the buildings at 1640 Marengo, the Department of Water and Power, 808 S. Olive, and 646 S. Olive in Los Angeles; two records from the building at 445 Figueroa in Los Angeles; and a single record from Fire Station No. 78, a CWR site at Lake Hughes, No. 1.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-73-29", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-73-29", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7329.pdf", "url": "https://authors.library.caltech.edu/records/jr717-ynm27/files/7329.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/fs1sw-x2407", "eprint_id": 26424, "eprint_status": "archive", "datestamp": "2023-08-19 09:16:39", "lastmod": "2023-10-24 16:19:03", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-H-L", "name": { "family": "Wong", "given": "Hung Leung" } } ] }, "title": "Dynamic soil-structure interaction", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1975: PB 247 233/AS", "abstract": "The dynamic response of a structure placed on a deformable soil medium subjected to seismic excitation is studied. The basic phenomena of soil-structure interaction was investigated by several analytical models supplemented by experimental observations; a brief review of literature in this discipline is also included.\n\nAmong the physical phenomena investigated: the effects caused by local topography, the interaction -with other structures, and the dissipation of dynamic energy through the soil medium were described by exact series solutions. Foundations of arbitrary shape, however, were modeled by using an approximate integral representation. This latter method utilizes the principle of superposition and provides flexibility in analyzing numerically the three-dimensional disc foundations placed on the soil surface. The results indicate that the detailed description for the shape of a rigid foundation placed on a deformable soil medium is not essential in the overall response of the superstructure, but the stress distribution under the disc foundation is quite sensitive to these changes in detail.\n\nIn this thesis, several methods for the calculation of foundation compliances for several types of foundation models were discussed, some of which have direct practical applications. The importance of the base input motion induced by incident seismic waves is also stressed, because the seismic input, along with the foundation compliances, are necessary for a complete analysis of this problem.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7501.pdf", "url": "https://authors.library.caltech.edu/records/fs1sw-x2407/files/7501.pdf" }, "pub_year": "1975", "author_list": "Wong, Hung Leung" }, { "id": "https://authors.library.caltech.edu/records/k9090-1jw26", "eprint_id": 26338, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:33", "lastmod": "2023-10-23 20:59:28", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - integrated ground velocity and displacement curves; Part V - Accelerograms IIV314 through IIV333", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIV314 IIV315 IIV316 IIV317 IIV318 IIV319 IIV320 IIV321 IIV322 IIV323 IIV324 IIV325 IIV326 IIV327 IIV328 IIV329 IIV330 IIV331 IIV332 IIV333", "note": "PB 242 948/AS", "abstract": "This issue, Volume II, Part V, Report No. EERL 75-52, contains California records from the Los Angeles and Long Beach areas, San Luis Obispo, various buildings in the San Francisco Bay area, Port Hueneme, Eureka, Castaic, and Sacramento during the years 1933 to 1967. Further records from some of these sites have appeared in other parts of the series.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-52", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-52", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7552.pdf", "url": "https://authors.library.caltech.edu/records/k9090-1jw26/files/7552.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/cz4fm-4eb17", "eprint_id": 26256, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:02", "lastmod": "2023-10-23 20:57:20", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part U - Accelerograms IIU294 through IIU313", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIU294 IIU295 IIU296 IIU297 IIU298 IIU299 IIU300 IIU301 IIU302 IIU303 IIU304 IIU305 IIU306 IIU307 IIU308 IIU309 IIU310 IIU311 IIU312 IIU313", "note": "PB 242 949/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital printout of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Part U, are the corrected accelerogram records contained in Volume II, Part U, Report No. EERL 75-51, and appeared in their uncorrected form in Volume I, Part U, Report No. EERL 73-26.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-81", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-81", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7581.pdf", "url": "https://authors.library.caltech.edu/records/cz4fm-4eb17/files/eerl7581.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/6wen1-4mg03", "eprint_id": 26343, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:13", "lastmod": "2023-10-23 20:59:39", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts V, W, and Y - Accelerograms IV294 to IV333, IIW334 to IIW336, IIW338, IIW339, IIW342 to IIW345, and IIY370 to IIY381", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIV294 IIV295 IIV296 IIV297 IIV298 IIV299 IIV300 IIV301 IIV302 IIV303 IIV304 IIV305 IIV306 IIV307 IIV308 IIV309 IIV310 IIV311 IIV312 IIV313 IIV314 IIV315 IIV316 IIV317 IIV318 IIV319 IIV320 IIV321 IIV322 IIV323 IIV324 IIV325 IIV326 IIV327 IIV328 IIV329 IIV330 IIV331 IIV332 IIV333 IIW334 IIW335 IIW336 IIW338 IIW339 IIW342 IIW343 IIW344 IIW345 IIY370 IIY371 IIY372 IIY373 IIY374 IIY375 IIY376 IIY377 IIY378 IIY379 IIY380 IIY381", "note": "PB 243 494/AS", "abstract": "The corrected records analyzed in this report, Volume IV, Parts V, W, and Y, appeared in Volume II, Part V, Report No. EERL 75-52, and Volume II, Parts W and Y, Report No. EERL 75-53. Their uncorrected versions were published in Volume I, Part V, Report No. EERL 73-27; Volume I, Part W, Report No. EERL 73-28; and Volume I, Part Y, Report No. EERL 73-30.", "date": "1975-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1975.EERL-75-101", "official_url": "https://resolver.caltech.edu/CaltechEERL:1975.EERL-75-101", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "75101.pdf", "url": "https://authors.library.caltech.edu/records/6wen1-4mg03/files/75101.pdf" }, "pub_year": "1975" }, { "id": "https://authors.library.caltech.edu/records/b3w26-fgw62", "eprint_id": 26284, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:38", "lastmod": "2023-10-23 20:57:47", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part R - Accelerograms IR244 through IR 254", "ispublished": "unpub", "full_text_status": "public", "keywords": "IR244 IR245 IR246 IR247 IR248 IR249 IR250 IR251 IR252 IR253 IR254 71.174 71.173 71.192 71.193 71.194 71.196 71.197 71.198 71.199 71.200 71.201", "note": "PB 239 585/AS", "abstract": "This issue continues the San Fernando accelerograms and contains eleven records consisting of one from the building at 6430 Sunset Boulevard in Los Angeles, and two each from the following locations: 222 Figueroa Street, 6464 Sunset Boulevard, 1900 Avenue of the Stars, 234 Figueroa Street, and 533 S. Fremont Avenue in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-23", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-23", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7323.pdf", "url": "https://authors.library.caltech.edu/records/b3w26-fgw62/files/7323.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/nrv06-4yj72", "eprint_id": 26308, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:53", "lastmod": "2023-10-23 20:58:41", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part H - Accelerograms IIH115 through IIHI26", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIH115 IIH116 IIH117 IIH118 IIH119 IIH120 IIH121 IIH122 IIH123 IIH124 IIH125 IIH126", "note": "PB 231 225/AS", "abstract": "This issue, Volume II, Part H, Report No. EERL 74-50, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes three records each from the buildings at 15250 Ventura Boulevard and 8639 Lincoln Avenue in Los Angeles, 900 South Fremont Avenue in Alhambra, and 2600 Nutwood in Fullerton.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-50", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-50", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7450.pdf", "url": "https://authors.library.caltech.edu/records/nrv06-4yj72/files/7450.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/pzcxe-std12", "eprint_id": 26321, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:01", "lastmod": "2023-10-23 20:59:03", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part N - Accelerograms IIN185 through IIN197", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIN185 IIN186 IIN187 IIN188 IIN189 IIN190 IIN191 IIN192 IIN193 IIN194 IIN195 IIN196 IIN197", "note": "PB 236 399/AS", "abstract": "This issue, Volume H, Part N, Report No. EERL 74-54, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes three records each from the buildings at 1800 Century Park East and 2500 Wilshire Boulevard in Los Angeles and one record each from Carbon Canyon Dam in Brea, Whittier Narrows Dam in Whittier, San Antonio Dam in Upland, 2516 Via Tejon in Palos Verdes Estates, the City Hall in San Juan Capistrano, Long Beach State College in Long Beach, and the Anza Post Office in Anza.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-54", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-54", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7454.pdf", "url": "https://authors.library.caltech.edu/records/pzcxe-std12/files/7454.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/yw3es-g1527", "eprint_id": 26257, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:08", "lastmod": "2023-10-23 20:57:22", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part H - Accelerograms IIH115 through IIH126", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIH115 IIH116 IIH117 IIH118 IIH119 IIH120 IIH121 IIH122 IIH123 IIH124 IIH125 IIH126", "note": "PB 232 237/AS", "abstract": "This is one of a series of reports presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. Volume IV, Part A, Report No. EERL 72-100, included an introduction summarizing Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In this Volume IV series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part H, appeared in Volume II, Part H, Report No. EERL 74-50. Their uncorrected versions were published in Volume I, Part H, Report No. EERL 72-21.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-100", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-100", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl74100.pdf", "url": "https://authors.library.caltech.edu/records/yw3es-g1527/files/eerl74100.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/j2507-3ge02", "eprint_id": 26324, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:23", "lastmod": "2023-10-23 20:59:10", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part H - Accelerograms IIH115 through IIH126", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIH115 IIH116 IIH117 IIH118 IIH119 IIH120 IIH121 IIH122 IIH123 IIH124 IIH125 IIH126", "note": "PB 231 319/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Part H, are the corrected accelerogram records of Volume II, Part H, Report No. EERL 74-50, and appeared in their uncorrected form in Volume I, Part H, Report No. EERL 72-21.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-80", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-80", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7480.pdf", "url": "https://authors.library.caltech.edu/records/j2507-3ge02/files/7480.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/ws6bc-f3680", "eprint_id": 26317, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:35", "lastmod": "2023-10-23 20:58:54", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Parts J and K - Accelerograms IIJ141 through IIJ150 and IIK157 through IIK160", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIJ141 IIJ142 IIJ143 IIJ144 IIJ145 IIJ146 IIJ147 IIJ148 IIJ149 IIJ150 IIK157 IIK158 IIK159 IIK160", "note": "PB 233 257/AS", "abstract": "This issue, Volume II, Parts J and K, Report No. EERL 74-52, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes four records from the Lake Hughes array, three records each from the buildings at 15107 Vanowen Street and 616 S. Normandie Avenue, and two records each from the buildings at 420 S. Grand Avenue and 750 Garland Avenue, all in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-52", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-52", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7452.pdf", "url": "https://authors.library.caltech.edu/records/ws6bc-f3680/files/7452.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/4frb4-kdz17", "eprint_id": 26326, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:40", "lastmod": "2023-10-23 20:59:14", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Parts M and N - Accelerograms IIM176 through IIM184 and IIN185 through IIN197", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIM176 IIM177 IIM178 IIM179 IIM180 IIM181 IIM182 IIM183 IIM184 IIN185 IIN186 IIN187 IIN188 IIN189 IIN190 IIN191 IIN192 IIN193 IIN194 IIN195 IIN196 IIN197", "note": "PB 236 400/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital printout of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Parts M and N, are the corrected accelerogram records contained in Volume II, Parts L and M, Report No. EERL 74-53, and Volume II, Part N, Report No. EERL 74-54, and appeared in their uncorrected form in Volume I, Part M, Report No. EERL 72-26, and Volume L Part N, Report No. EERL 72-27.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-83", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-83", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7483.pdf", "url": "https://authors.library.caltech.edu/records/4frb4-kdz17/files/7483.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/xwahw-1bh26", "eprint_id": 26319, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:47", "lastmod": "2023-10-23 20:58:59", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts J, K, L, and M - Accelerograms IIJ141 through IIJ150, IIK157 through IIK160, IIL166 through IIL175, and IIM176 through IIM184", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIJ141 IIJ142 IIJ143 IIJ144 IIJ145 IIJ146 IIJ147 IIJ148 IIJ149 IIJ150 IIK157 IIK158 IIK159 IIK160 IIL166 IIIL167 IIL168 IIL169 IIL170 IIL171 IIL172 IIL173 IIL174 IIL175 IIM176 IIM177 IIM178 IIM179 IIM180 IIM181 IIM182 IIM183 IIM184", "note": "PB 236 111/AS", "abstract": "For each earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In this Volume IV series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Parts J, K, L, and M, appeared in Volume II, Parts J and K, Report No. EERL 74-52, and Volume II, Parts L and M, Report No. EERL 74-53. Their uncorrected versions were published in Volume I, Part J, Report No. EERL 72-23; Volume I, Part K, Report No. EERL 72-24; Volume I, Part L, Report No. EERL 72-25; and Volume I, Part M, Report No. EERL 72-26.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-102", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-102", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "74102.pdf", "url": "https://authors.library.caltech.edu/records/xwahw-1bh26/files/74102.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/qyqvj-db005", "eprint_id": 26323, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:16", "lastmod": "2023-10-23 20:59:08", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Parts Q and R - Accelerograms IIQ233 to IIQ243 and IIR244 to IIR254", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIQ233 IIQ234 IIQ235 IIQ236 IIQ237 IIQ238 IIQ239 IIQ240 IIQ241 IIQ242 IIQ243 IIP244 IIP245 IIP246 IIP247 IIP248 IIP249 IIP250 IIP251 IIP252 IIP253 IIP254", "note": "PB 239 587/AS", "abstract": "This issue, Volume H, Parts Q and R, Report No. EERL 74-56, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes three records each from the buildings at 14724 Ventura Boulevard and 800 W. First Street in Los Angeles and 1760 N. Orchid Avenue in Hollywood; two records from the buildings at 222 Figueroa Street, 6464 Sunset Boulevard, 1900 Avenue of the Stars, 234 Figueroa Street, and 533 S. Fremont in Los Angeles and 9100 Wilshire Boulevard in Beverly Hills; and one record from the building at 6430 Sunset Boulevard in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-56", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-56", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7456.pdf", "url": "https://authors.library.caltech.edu/records/qyqvj-db005/files/7456.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/r9b0v-3tm33", "eprint_id": 26350, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:44", "lastmod": "2023-10-23 20:59:48", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts Q, R and S - Accelerograms IIQ233 to IIQ243, IIR244 to IIR254, IIS255 to IIS273", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIQ233 IIQ234 IIQ235 IIQ236 IIQ237 IIQ238 IIQ239 IIQ240 IIQ241 IIQ242 IIQ243 IIR244 IIR245 IIR246 IIR247 IIR248 IIR249 IIR250 IIR251 IIR252 IIR253 IIR254 IIS255 IIS256 IIS257 IIS258 IIS259 IIS260 IIS261 IIS262 IIS263 IIS264 IIS265 IIS266 IIS267 IIS268 IIS269 IIS270 IIS271 IIS272 IIS273", "note": "PB 241 554/AS", "abstract": "The corrected records analyzed in this report, Volume IV, Parts Q, R, and S, appeared in Volume II, Parts Q and R, Report No. EERL 74-56, and Volume II, Part S, Report No. EERL 74-57. Their uncorrected versions were published in Volume I, Part Q, Report No. EERL 73-22; Volume I, Part R, Report No. EERL 73-23; and Volume I, Part S, Report No. EERL 73-24.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-104", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-104", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "74104.pdf", "url": "https://authors.library.caltech.edu/records/r9b0v-3tm33/files/74104.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/jfctd-syy59", "eprint_id": 26320, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:54", "lastmod": "2023-10-23 20:59:01", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts N, O, and P - Accelerograms IIN185 to IIN197, IIO198 to IIO201, IIO213, IIP214 to IIP223, IIP231 and IIP232", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIN182 IIN186 IIN187 IIN188 IIN189 IIN190 IIN191 IIN192 IIN193 IIN194 IIN195 IIN196 IIN197 IIO198 IIO199 IIO200 IIO201 IIO204 IIO205 IIO206 IIO207 IIO208 IIO210 IIO213 IIP214 IIP215 IIP216 IIP217 IIP218 IIP219 IIP220 IIP221 IIP222 IIP223 IIP231 IIP232", "note": "PB 238 447/AS", "abstract": "For each earthquake accelerogram, two spectrum plots are given -- a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In this Volume IV series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Parts N, O, and P, appeared in Volume II, Part N, Report No. EERL 74-54, and Volume II, Parts O and P, Report No. EERL 74-55. Their uncorrected versions were published in Volume I, Part N, Report No. EERL 72-27; Volume I, Part O, Report No. EERL 73-20; and Volume I, Part P, Report No. EERL 73-21.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-103", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-103", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "74103.pdf", "url": "https://authors.library.caltech.edu/records/jfctd-syy59/files/74103.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/cn0wf-pjh71", "eprint_id": 26294, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:57", "lastmod": "2023-10-23 20:58:09", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part S - Accelerograms IS255 through IS273, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IS255 IS256 IS257 IS258 IS259 IS260 IS261 IS262 IS263 IS264 IS265 IS266 IS267 IS268 IS269 IS270 IS271 IS272 IS273 71.178 71.179 71.177 71.181 71.180 71.182 71.183 71.185 71.184 71.186 71.187 71.188 71.190 71.191 71.189 71.195 71.202 71.203 71.204", "note": "PB 241 551/AS", "abstract": "This issue completes the San Fernando accelerograms and contains nineteen records consisting of three records each from the buildings at 6200 Wilshire Boulevard, 3440 University Avenue, 5900 Wilshire Boulevard, and 5260 Century Boulevard; two records from the building at 11661 San Vicente Boulevard; and one record from the buildings at 1177 Beverly Drive, 3435 Wilshire Boulevard, 3550 Wilshire Boulevard, 930 Hilgard Boulevard, and 15433 Ventura Boulevard; all in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-73-24", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-73-24", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7324.pdf", "url": "https://authors.library.caltech.edu/records/cn0wf-pjh71/files/7324.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/0p6hj-f1r98", "eprint_id": 26309, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:59", "lastmod": "2023-10-23 20:58:43", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part I - Accelerograms II-I-128 through II-I-139", "ispublished": "unpub", "full_text_status": "public", "keywords": "II-I-128 II-I-129 II-I-130 II-I-131 II-I-132 II-I-133 II-I-134 II-I-135 II-I-136 II-I-137 II-I-138 II-I-139", "note": "PB 232 316/AS", "abstract": "This issue, Volume II, Part I, Report No. EERL 74-51, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes three records each from the buildings at 435 N. Oakhurst Avenue and 420 N. Roxbury Drive in Beverly Hills, and 1800 Century Park East and 15910 Ventura Boulevard in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-51", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-51", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7451.pdf", "url": "https://authors.library.caltech.edu/records/0p6hj-f1r98/files/7451.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/hgcgw-xjw69", "eprint_id": 26322, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:08", "lastmod": "2023-10-23 20:59:05", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Parts O and P - Accelerograms IIO198 to IIO201, IIO204 to IIO208, IIO210, IIO213, IIP214 to ...", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIO198 IIO199 IIO200 IIO201 IIO202 IIO203 IIO204 IIO205 IIO206 IIO207 IIO208 IIO210 IIO213 IIP214 IIP215 IIP216 IIP217 IIP218 IIP219 IIP220 IIP221 IIP222 IIP223 IIP231 IIP232", "note": "PB 239 586/AS", "abstract": "This issue, Volume II, Parts O and P, Report No. EERL 74-55, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes three records each from the buildings at 1625 Olympic Boulevard, 4867 Sunset Boulevard, and 3345 Wilshire Boulevard in Los Angeles; two records from the building at 9841 Airport Boulevard in Los Angeles; and one record each from the Griffith Park Observatory in Los Angeles, the Utilities Building at 215 W. Broadway, and Terminal Island, both in Long Beach, the Hall of Records in San Bernardino, the Fairmont Reservoir, the University of California at Santa Barbara, the Hemet Fire Station in Hemet, the 1215 Gallery at Hoover Dam, 666 W. 19th Street in Costa Mesa, the Santa Anita Reservoir in Arcadia, the Navy Laboratory at Port Hueneme, and the Puddingstone Reservoir at San Dimas.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-55", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-55", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7455.pdf", "url": "https://authors.library.caltech.edu/records/hgcgw-xjw69/files/7455.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/c9z96-ggh40", "eprint_id": 26436, "eprint_status": "archive", "datestamp": "2023-08-19 08:48:05", "lastmod": "2023-10-24 16:19:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jephcott-D-K", "name": { "family": "Jephcott", "given": "Donald K." } }, { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "The performance of public school plants during the San Fernando earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "PB 240 000/AS", "abstract": "The epicenter of the San Fernando earthquake was just 25 miles from the Earthquake Engineering Research Laboratory of the California Institute of Technology, which has been for some 50 years actively studying the problem of earthquake resistant design. It was therefore most natural that the EERL was very quickly involved in a number of major investigations growing out of the event. Several Earthquake Engineering research grants from the National Science Foundation to the EERL were in effect at the time and provided the framework for an expanded NSF sponsorship of additional special studies.\n\nThese expanded NSF assignments included a responsibility to investigate those aspects of earthquake damage for which important evidence might quickly disappear through demolition, repairs, etc., and also those for which significant studies might otherwise not be made because of a lack of adequate resources. Both of these aspects were involved in the important matter of the earthquake behavior of school buildings.\n\nThe whole question of the earthquake safety of the schools very quickly came to the attention of the EERL staff, through service on the Los Angeles County Earthquake Commission, as consultants to the Los Angeles Unified School District in evaluating the postearthquake safety of schools, and a natural historical consequence of past studies of the Long Beach 1933 earthquake. Since it became apparent that detailed studies of the school situation were not likely to be made by existing public agencies, it was decided that a portion of the NSF emergency grant resources should be used for this purpose. These resources were later expanded by NSF through a supplemental research grant for the particular objective of completing a comprehensive report on the behavior of school buildings during the San Fernando Earthquake.\n\nThe San Fernando earthquake was an unusually valuable test of school safety because: (1) there were several hundred schools having structures of all types in the heavily-shaken area, including 10 schools within 5 miles of the epicenter; (Z) the severity of ground motion is believed to have been near the maximum to be expected for an earthquake of any size--a number of campuses were subjected to major ground cracking and deformation; (3) since there were many instruments in the area, the details of the earthquake ground motion are better known than for any other earthquake. On some campuses, pre-Field Act buildings, renovated pre-Field Act buildings, and new buildings existed side by side, and direct comparisons show the efficacy of the Field Act and the associated plan check and field inspection procedures in reducing the earthquake hazard to an acceptably low level.\n\nThe study became feasible through the cooperation of the California State Office of Architecture and Construction in making available as a consultant the services of Mr. Donald K. Jephcott, Principal Structural Engineer in charge of the Structural Safety Section (formerly Schoolhouse Section) of the Los Angeles office. Two members of Mr. Jephcott's staff, Mr. Leon Stein and Mr. Byrne Eggenburger, assisted as consultants in the preparation of several of the detailed descriptions of the school plants. We are also much indebted to the Los Angeles Unified School District for making available much information and many drawings which simplified our task.\n\nWe are pleased to acknowledge also the assistance of the Earthquake Research Affiliates program of the California Institute of Technology in providing financial support for portions of this study.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7401.pdf", "url": "https://authors.library.caltech.edu/records/c9z96-ggh40/files/7401.pdf" }, "pub_year": "1974", "author_list": "Jephcott, Donald K. and Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/53q03-dsn62", "eprint_id": 26310, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:06", "lastmod": "2023-10-23 20:58:45", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Parts L and M - Accelerograms IIL166 through IIL175 and IIM176 through IIM184", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIL166 IIL167 IIL168 IIL169 IIL170 IIL171 IIL172 IIL173 IIL174 IIL175 IIM176 IIM177 IIM178 IIM179 IIM180 IIM181 IIM182 IIM183 IIM184", "note": "PB 237 174/AS", "abstract": "This issue, Volume II, Parts L and M, Report No. EERL 74-53, continues with the accelerograms obtained during the San Fernando earthquake of February 9, 1971, and includes four records from the building at 1888 Century Park East, Los Angeles, three records each from the buildings at 3838 Lankershim Boulevard and 1150 S. Hill St., Los Angeles, and 4000 W. Chapman Avenue, Orange, two records each from the buildings at 945 Tiverton Avenue, Los Angeles, and 6074 Park Drive, Wrightwood, and one record each from the Southern California Edison Nuclear Power Plant in San Onofre and the California Water Resources Tehachapi Pumping Plant at Grapevine.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-53", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-53", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7453.pdf", "url": "https://authors.library.caltech.edu/records/53q03-dsn62/files/7453.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/07ekt-rt472", "eprint_id": 26318, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:40", "lastmod": "2023-10-23 20:58:56", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part I - Accelerograms II-I-128 through II-I-139", "ispublished": "unpub", "full_text_status": "public", "keywords": "I-II-128 I-II-129 I-II-130 I-II-131 I-II-132 I-II-133 I-II-134 I-II-135 I-II-136 I-II-137 I-II-138 I-II-139", "note": "PB 232 328/AS", "abstract": "In this Volume IV series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part I, appeared in Volume II, Part 1, Report No. EERL 74-51. Their uncorrected versions were published in Volume I, Part I, Report No. EERL 72-22.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-101", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-101", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "74101.pdf", "url": "https://authors.library.caltech.edu/records/07ekt-rt472/files/74101.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/est91-et256", "eprint_id": 26455, "eprint_status": "archive", "datestamp": "2023-08-19 08:48:11", "lastmod": "2023-10-24 16:20:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irvine-Hilary-Max", "name": { "family": "Irvine", "given": "Hilary Max" } } ] }, "title": "Studies in the statics and dynamics of simple cable systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1974\n\nAccepted Version - DYNL108.pdf
", "abstract": "An investigation is made of the static and dynamic response of simple cable systems to applied load. Both the single, suspended cable and the counterstressed double cable system (the cable truss) are treated. More complicated systems, such as cable nets, are not treated. The geometry of the simple cable systems is such that the c able slopes are, and remain, small. For example, the ratio of sag to span of the suspended cable must be about 1:8, or less.\n\nClosed form solutions are given to a variety of cable problems which have important applications in practice. The work is divided into two chapters.\n\nIn the first chapter solutions are given for the response of a single, suspended cable to static loading, and a comprehensive theory is presented for the free, linear vibrations of the suspended cable. Where necessary, in the static analyses, the solutions are given accurate to the second order of small quantities. The results of simple experiments are reported.\n\nThe second chapter deals with the cable truss and, again, static analyses are given and a theory is presented for the free, linear vibrations of the cable truss. The possible lateral instability of the cable truss under applied load is investigated.\n\nAn attempt is made to give static solutions which are of general significance. In the part this has rarely been done. It is shown that a parameter which involves cable elasticity and geometry has a very important bearing on several of the theories presented. The parameter does not appear to have been given before and, for this reason, most previous works are of limited applicability and in some cases they are wrong. For example, the linear in-plane vibrations of these simple cable systems can be analyzed correctly only if this parameter is included. The lateral instability of the cable truss is important, not only because previously it appears that it has been ignored, but also because it opens up a new field of buckling problems which are unlike any others.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.DYNL-108", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.DYNL-108", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Dynamics-Laboratory" }, { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "doi": "10.7907/K4Y4-8H02", "primary_object": { "basename": "DYNL108.pdf", "url": "https://authors.library.caltech.edu/records/est91-et256/files/DYNL108.pdf" }, "pub_year": "1974", "author_list": "Irvine, Hilary Max" }, { "id": "https://authors.library.caltech.edu/records/57fkp-jt720", "eprint_id": 26252, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:33", "lastmod": "2023-10-23 20:57:13", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Parts Q and R - Accelerograms IIQ233 through IIQ243, IIR244 through IIR254", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIQ233 IIQ234 IIQ235 IIQ236 IIQ237 IIQ238 IIQ239 IIQ240 IIQ241 IIQ242 IIQ243 IIR244 IIR245 IIR246 IIR247 IIR248 IIR249 IIR250 IIR251 IIR252 IIR253 IIR254", "note": "PB 240 688/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital printout of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Parts Q and R, are the corrected accelerogram records contained in Volume II, Parts Q and R, Report No. EERL 74-56, and appeared in their uncorrected form in Volume I, Part Q, Report No. EERL 73-22, and Volume I, Part R, Report No. EERL 73-23.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-85", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-85", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7485.pdf", "url": "https://authors.library.caltech.edu/records/57fkp-jt720/files/eerl7485.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/0fash-tre52", "eprint_id": 26336, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:18", "lastmod": "2023-10-23 20:59:24", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Parts O and P - Accelerograms IIO198 to IIO201,IIO204 to IIO208, IIO210, IIO213, IIP214 to IIP223, IIP231 and IIP232", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIO198 IIO199 IIO200 IIO201 IIO202 IIO203 IIO204 IIO205 IIO206 IIO207 IIO208 IIO210 IIO213 IIP214 IIP215 IIP216 IIP217 IIP218 IIP219 IIP220 IIP221 IIP222 IIP223 IIP231 IIP232", "note": "PB 238 102/AS", "abstract": "The records analyzed in this report, Volume III, Parts O and P, are the corrected accelerogram records contained in Volume II, Parts O and P, Report No. EERL 74-55, and appeared in their uncorrected form in Volume I, Part O, Report No. EERL 73-20, and Volume I, Part P, Report No. EERL 73-21.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-84", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-84", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7484.pdf", "url": "https://authors.library.caltech.edu/records/0fash-tre52/files/7484.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/yg9b7-f6h76", "eprint_id": 26255, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:52", "lastmod": "2023-10-23 20:57:17", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part S - Accelerograms IIS255 through IIS273", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIS255 IIS256 IIS257 IIS258 IIS259 IIS260 IIS261 IIS262 IIS263 IIS264 IIS265 IIS266 IIS267 IIS268 IIS269 IIS270 IIS271 IIS272 IIS273", "note": "PB 241 553/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given -relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital printout of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this', report, Volume III, Part S, are the corrected accelerogram records contained in Volume II, Part S, Report No. EERL 74-57, and appeared in their uncorrected form in Volume I, Part S, Report No. EERL 73-24.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-86", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-86", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7486.pdf", "url": "https://authors.library.caltech.edu/records/yg9b7-f6h76/files/eerl7486.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/a23fn-6h448", "eprint_id": 26325, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:32", "lastmod": "2023-10-23 20:59:12", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Parts J, K, and L - Accelerograms IIJ141 through IIJ150, IIK157 through IIK160, and IIL166 through IIL175", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIJ141 IIJ142 IIJ143 IIJ144 IIJ145 IIJ146 IIJ147 IIJ148 IIJ149 IIJ150 IIK157 IIK158 IIK159 IIK160 IIL166 IIL167 IIL168 IIL169 IIL170 IIL171 IIL172 IIL173 IIL174 IIL175", "note": "PB 236 110/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected accelerograms. In the preface to the first part, Volume HI, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudovelocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume M, Parts J, K, and L, are the corrected accelerogram records of Volume H, Parts J and K, Report No. EERL 74-52, and Volume 11, Part L, Report No. EERL 74-53, and appeared in their uncorrected form in Volume I, Part J, Report No. EERL 72-23; Volume I, Part K, Report No. EERL 72-24; and Volume I, Part L, Report No. EERL 72-25.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-82", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-82", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7482.pdf", "url": "https://authors.library.caltech.edu/records/a23fn-6h448/files/7482.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/7xrmb-tct57", "eprint_id": 26311, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:13", "lastmod": "2023-10-23 20:58:47", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part S - Accelerograms IIS255 through IIS273", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIS255 IIS256 IIS257 IIS258 IIS259 IIS260 IIS261 IIS262 IIS263 IIS264 IIS265 IIS266 IIS267 IIS268 IIS269 IIS270 IIS271 IIS272 IIS273", "note": "PB 241 552/AS", "abstract": "This issue, Volume II, Part S, Report No. EERL 74-57, includes the final accelerograms obtained during the San Fernando earthquake of February 9, 1971, and comprises three records each from the buildings at 6200 Wilshire Boulevard, 3440 University Avenue, 5900 Wilshire Boulevard, and 5260 Century Boulevard; two records from the building at 11661 San Vicente Boulevard; and one record each from the buildings at 1177 Beverly Drive, 3435 Wilshire Boulevard, 3550 Wilshire Boulevard, 930 Hilgard Avenue, and 15433 Ventura Boulevard; all in Los Angeles.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-57", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-57", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7457.pdf", "url": "https://authors.library.caltech.edu/records/7xrmb-tct57/files/7457.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/kd3cf-x9a84", "eprint_id": 26341, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:59", "lastmod": "2023-10-23 20:59:35", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part I - Accelerograms II-I-128 through II-I-139", "ispublished": "unpub", "full_text_status": "public", "keywords": "II-I-128 II-I-129 II-I-130 II-I-131 II-I-132 II-I-133 II-I-134 II-I-135 II-I-136 II-I-137 II-I-138 II-I-139", "note": "PB 232 326/AS", "abstract": "The records analyzed in this report, Volume III, Part I, are the corrected accelerogram records of Volume II,\nPart I, Report No. EERL 74-51, and appeared in their uncorrected form in Volume I, Part I, Report No. EERL 72-22.", "date": "1974-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1974.EERL-74-81", "official_url": "https://resolver.caltech.edu/CaltechEERL:1974.EERL-74-81", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7481.pdf", "url": "https://authors.library.caltech.edu/records/kd3cf-x9a84/files/7481.pdf" }, "pub_year": "1974" }, { "id": "https://authors.library.caltech.edu/records/f72eh-10d86", "eprint_id": 26286, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:53", "lastmod": "2023-10-23 20:57:52", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part G - Accelerograms IIG106 through IIG114", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIG106 IIG107 IIG108 IIG109 IIG110 IIG111 IIG112 IIG113 IIG114", "note": "PB 231 223/AS", "abstract": "This is one of a series of reports presenting earthquake response spectrum curves calculated from corrected ground accelerograms. In the preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for users of the data. For each earthquake accelerogram, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this report, Volume III, Part G, are the corrected accelerogram records of Volume II, Part G, Report No. EERL 73-52, and appeared in their uncorrected form in Volume I, Part G, Report No. EERL 72-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-85", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-85", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7385.pdf", "url": "https://authors.library.caltech.edu/records/f72eh-10d86/files/7385.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/g8ed0-nmc49", "eprint_id": 26293, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:44", "lastmod": "2023-10-23 20:58:07", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part P - Accelerograms IP214 through IP232, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IP214 IP215 IP216 IP217 IP218 IP219 IP220 IP221 IP222 IP223 IP224 IP225 IP226 IP227 IP228 IP229 IP230 IP231 IP232 71.053 71.054 71.055 71.108 71.109 71.110 71.148 71.150 71.151 71.153 71.237 71.238 71.242 71.239 71.240 71.241 71.243 71.160 71.161", "note": "PB 227 481/AS", "abstract": "This issue continues the San Fernando accelerograms and contains nineteen records consisting of one each from the following locations: 666 W. 19th Street in Costa Mesa, Santa Anita Reservoir in Arcadia, Navy Laboratory at Port Hueneme, Puddingstone Reservoir at San Dimas, Harvey Auditorium in Bakersfield, Light and Power Co. Service Building in San Diego, and the Buena Vista CWR, site; two records each from the Lincoln High School in Taft, the Cholame-Shandon Array (Stations 2 and 8) and 9841 Airport Boulevard; and three records each from the buildings at 4867 Sunset Boulevard and 3345 Wilshire Boulevard in Los Angeles.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-21", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-21", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7321.pdf", "url": "https://authors.library.caltech.edu/records/g8ed0-nmc49/files/7321.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/8nkhm-72x86", "eprint_id": 26306, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:37", "lastmod": "2023-10-23 20:58:36", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part O - Accelerograms 1O198 Through 1O213, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IO198 IO199 IO200 IO201 IO202 IO203 IO204 IO205 IO206 IO207 IO208 IO209 IO210 IO211 IO212 IO213 71.069 71.072 71.075 71.090 71.145 71.248 71.149 71.154 71.158 71.175 71.176 71.231 71.234 71.244 71.245 71.246", "note": "PB 222 417", "abstract": "This issue continues the San Fernando accelerograms and contains sixteen records consisting of one each from the following locations: Griffith Park Observatory in Los Angeles, Allen Ranch and Pump House at Cedar Springs, 215 W. Broadway and Terminal Island in Long Beach, Hall of Records in San Bernardino, Fairmont Reservoir, University of California at Santa Barbara, Community Hospital in El Centro, and the Hose Storage Room at the Hemet Fire Station; and three records each from the building located at 1625 Olympic Boulevard in Los Angeles and Hoover Dam on the Colorado River.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-20", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-20", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7320.pdf", "url": "https://authors.library.caltech.edu/records/8nkhm-72x86/files/7320.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/h2gnf-4hg19", "eprint_id": 26245, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:02", "lastmod": "2023-10-23 20:57:04", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part C - Accelerograms IIC041 through IIC055", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIC041 IIC042 IIC043 IIC044 IIC045 IIC046 IIC047 IIC048 IIC049 IIC050 IIC051 IIC052 IIC053 IIC054 IIC055", "note": "PB 223 025", "abstract": "This is the third report of a series presenting earthquake response spectrum curves calculated from corrected ground accelerograms. In the Preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for users of the data. For each earthquake accelerograrn, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this Volume III, Part C, are the corrected accelerogram data of Volume II, Part C, Report No. EERL 72-51, and appeared in their uncorrected form in Volume I, Part C, Report No. EERL 71-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-81", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-81", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7381.pdf", "url": "https://authors.library.caltech.edu/records/h2gnf-4hg19/files/eerl7381.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/sjrt7-k0r22", "eprint_id": 26305, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:29", "lastmod": "2023-10-23 20:58:34", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part B - Accelerograms IIB021 through IIB040", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIB021 IIB022 IIB023 IIB024 IIB025 IIB026 IIB027 IIB028 IIB029 IIB030 IIB031 IIB032 IIB033 IIB034 IIB035 IIB036 IIB037 IIB038 IIB039 IIB040", "note": "PB 221 256", "abstract": "The earthquakes in Part B match the uncorrected accelerogram data of Volume I, Part B, Report No. EERL 70-21 and the corrected accelerogram data of Volume II, Part B, Report No. EERL 72-50.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-80", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-80", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7380.pdf", "url": "https://authors.library.caltech.edu/records/sjrt7-k0r22/files/7380.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/5fx2k-r7x48", "eprint_id": 26316, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:28", "lastmod": "2023-10-23 20:58:52", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part F - Accelerograms IIF086 through IIF105", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIF086 IIF087 IIF088 IIF089 IIF090 IIF091 IIF092 IIF093 IIF094 IIF095 IIF096 IIF097 IIF098 IIF099 IIF100 IIF101 IIF102 IIF103 IIF104 IIF105", "note": "PB 229 241/AS", "abstract": "For each earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale, and a log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part F, appeared in Volume II, Part F, Report No. EERL 73-51. Their uncorrected versions were published in Volume I, Part F, Report No. EERL 71-23.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-104", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-104", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "73104.pdf", "url": "https://authors.library.caltech.edu/records/5fx2k-r7x48/files/73104.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/ymk6j-4fz39", "eprint_id": 26292, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:35", "lastmod": "2023-10-23 20:58:05", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part C - Accelerograms IIC041 through IlC055", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIC041 IIC042 IIC043 IIC044 IIC045 IIC046 IIC047 IIC048 IIC049 IIC050 IIC051 IIC052 IIC053 IIC054 IIC055", "note": "PB 222 514", "abstract": "This is the third report (Part C) of a series (Volume IV series) presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. Volume IV, Part A, Report No. EERL 72-100 included an introduction summarizing Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given\n\n Fourier amplitude spectrum versus frequency on a linear scale, and\n\n log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part C, appeared in Volume II, Part C, Report No. EERL 72-51. Their uncorrected versions were published in Volume I, Part C, Report No. EERL 71-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-101", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-101", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "73101.pdf", "url": "https://authors.library.caltech.edu/records/ymk6j-4fz39/files/73101.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/az0tb-nk116", "eprint_id": 26281, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:12", "lastmod": "2023-10-23 20:57:41", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part D - Accelerograms IID056 through IID070", "ispublished": "unpub", "full_text_status": "public", "keywords": "IID056 IID057 IID058 IID059 IID060 IID061 IID062 IID063 IID064 IID065 IID066 IID067 IID068 IID069 IID070", "note": "PB 220 836", "abstract": "The first set of twenty corrected earthquake accelerograms was published in September 1971, as Volume II, Part A, Report EERL 71-50, the first report of the Volume II series. That issue also contained introductory material and background information describing the types of corrections used. The corresponding uncorrected data appeared earlier in Volume I, Part A, Report EERL 70-20. Both of these reports, containing references related to the records themselves and the various procedures, should be referred to by all users of the data. This issue, Volume II, Part D, Report EERL 72-52 contains accelerograms obtained during the San Fernando Earthquake of February 9, 1971 and includes in particular the record from the Old Ridge Route at Castaic, two ground level records from the Hollywood Storage Building, and three records each from the buildings at 1901 Avenue of the Stars, 1640 South Marengo Street, 3710 Wilshire Boulevard, and 7080 Hollywood Boulevard. The uncorrected versions of the accelerograms in this issue appeared earlier in Volume I, Part D, Report EERL 71-21.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-72-52", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-72-52", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7252.pdf", "url": "https://authors.library.caltech.edu/records/az0tb-nk116/files/7252.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/tb8cn-7xa86", "eprint_id": 26303, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:12", "lastmod": "2023-10-23 20:58:29", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part E - Accelerograms IIE071 through IIE085", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIE070 IIE071 IIE072 IIE073 IIE074 IIE075 IIE076 IIE077 IIE078 IIE079 IIE080 IIE081 IIE082 IIE083 IIE084 IIE085", "note": "PB 223 024", "abstract": "This issue, Volume II, Part E, Report No. EERL 73-50 continues with the accelerograms obtained during the San Fernando Earthquake of February 9, 1971 and includes one record from Wheeler Ridge, three records each from the buildings at 4680 Wilshire Boulevard, 3470 Wilshire Boulevard, the L. A. Water and Power Building, and 3407 6th Street, all in Los Angeles, and two records from the Santa Felicia Dam. The uncorrected versions of the accelerograms in this issue appeared earlier in Volume I, Part E, Report EERL 71-22.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-50", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-50", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7350.pdf", "url": "https://authors.library.caltech.edu/records/tb8cn-7xa86/files/7350.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/r9aaq-4c388", "eprint_id": 26423, "eprint_status": "archive", "datestamp": "2023-08-19 08:19:29", "lastmod": "2023-10-24 16:19:01", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iemura-H", "name": { "family": "Iemura", "given": "H." } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Hysteretic response of a nine story reinforced concrete building during the San Fernando Earthquake", "ispublished": "unpub", "full_text_status": "public", "abstract": "The Millikan Library on the campus of the California Institute of Technology was strongly shaken during the San Fernando earthquake of February 9, 1971. The building was not damaged structurally, but the observed E-W response of the building showed a fundamental period of about 1. 0 sec, significantly longer than the 0. 66 sec observed in preearthquake vibration tests. In this study, the response of the fundamental mode was treated as that of a single- degree- of- freedom hysteretic structure, and four simple models, two stationary and two with changing properties, were examined to see if they could describe the observed response. It was found that an equivalent linear model and a bilinear hysteretic model both could match the response, provided their properties were changed during the earthquake. (Four changes were used). A linear model with constant properties and a stationary, bilinear hysteretic model did not give nearly as good agreement as the nonstationary models. The results indicated, in general, a degrading of the stiffness and energy dissipation capacity of the building, but it could not be determined whether the changes were sudden or gradual.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7307.pdf", "url": "https://authors.library.caltech.edu/records/r9aaq-4c388/files/7307.pdf" }, "pub_year": "1973", "author_list": "Iemura, H. and Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/g3nn4-fh111", "eprint_id": 26254, "eprint_status": "archive", "datestamp": "2023-09-14 22:02:11", "lastmod": "2023-10-23 20:56:53", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part D - Accelerograms IID056 through IID070", "ispublished": "unpub", "full_text_status": "public", "keywords": "IID056 IID057 IID058 IID059 IID060 IID061 IID062 IID063 IID064 IID065 IID066 IID067 IID068 IID069 IID070", "note": "PB 222 969/AS", "abstract": "This is the fourth report (Part D) of a series (Volume IV series) presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. Volume IV, Part A, Report No. EERL 72-100 included an introduction summarizing Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale, and a log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part D, appeared in Volume II, Part D, Report No. EER.L 72-52. Their uncorrected versions were published in Volume I, Part D, Report No. EERL 71-21.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-102", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-102", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl73102.pdf", "url": "https://authors.library.caltech.edu/records/g3nn4-fh111/files/eerl73102.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/4w6n2-23j50", "eprint_id": 26301, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:57", "lastmod": "2023-10-23 20:58:25", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part M - Accelerograms IM 176 through IM 184, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IM176 IM177 IM118 IM179 IM180 IM181 IM182 IM183 IM184 71.035 71.034 71.033 71.061 71.123 71.124 71.125 71.157 71.159", "note": "PB 220 554", "abstract": "This issue continues the San Fernando accelerograms and contains nine records consisting of three from 1150 South Hill Street in Los Angeles, three from 4000 West Chapman Avenue in Orange, two from 6074 Park Drive in Wrightwood, and one record from the Tehachapi Pumping Plant in Grapevine.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-72-26", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-72-26", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7226.pdf", "url": "https://authors.library.caltech.edu/records/4w6n2-23j50/files/7226.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/n6b8c-ahd95", "eprint_id": 26414, "eprint_status": "archive", "datestamp": "2023-08-19 08:19:10", "lastmod": "2023-10-24 16:18:45", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Routine computer processing of strong-motion accelerograms", "ispublished": "unpub", "full_text_status": "public", "note": "PB 226 047/AS", "abstract": "This report contains short descriptions, flow charts and listings of the computer programs that are currently being used for routine processing of strong-motion accelerograms at the Earthquake Engineering Research Laboratory of the California Institute of Technology. All programs are in Fortran IV.\n\nThe programs are presented in five groups corresponding to the processing scheme developed at the Earthquake Engineering Research Laboratory for Volume I, II, III, IV, and eventually Volume V reports (Hudson, et al, 1969; Hudson, et al, 1971; Hudson, et al, 1972a; and Hudson, et al, 1972b). The programs belonging to the Volume I operation are used to check the raw digitized data, to perform the elementary corrections for time and fixed base line, and to scale the raw digitized acceleration data to seconds and G/10 (G is the acceleration of gravity = 981 cm/sec'). The programs belonging to Volume II processing perform the instrument and base line corrections and calculate ground velocity and displacement. The programs for Volume III processing calculate the true velocity spectra, the Fourier amplitude spectra and the pseudo velocity spectra, while the programs for Volume IV compute the Fourier amplitude spectra using the Fast Fourier Transform approach. On the completion of the various stages of processing the output data are plotted, tabulated, punched on cards, and stored on magnetic tapes. The programs for Volume V processing at present plot the RES curves on linear and logarithmic scales by reading the Volume V tape containing the corrected accelerogram and the RES amplitudes.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7303.pdf", "url": "https://authors.library.caltech.edu/records/n6b8c-ahd95/files/7303.pdf" }, "pub_year": "1973", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/gyjw5-6xv95", "eprint_id": 26296, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:12", "lastmod": "2023-10-23 20:58:14", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part G - Accelerograms IIG106 through IlGI14", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIG106 IIG107 IIG108 IIG109 IIG110 IIG111 IIG112 IIG113 IIG114", "note": "PB 229 239/AS", "abstract": "This issue, Volume II, Part G, Report No. EERL 73-52 continues with the accelerograms obtained during the San Fernando Earthquake of February 9, 1971 and includes one record each from Caltech's Seismological Laboratory and Athenaeum in Pasadena and the Palmdale Fire Station; and two records each from Caltech's Millikan Library and Jet Propulsion Laboratory in Pasadena, and the building at 611 W. Sixth Street in Los Angeles. The uncorrected versions of the accelerograms in this issue appeared earlier in Volume I, Part G, Report EERL 72-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-52", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-52", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7352.pdf", "url": "https://authors.library.caltech.edu/records/gyjw5-6xv95/files/7352.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/1ydmy-p1r05", "eprint_id": 26297, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:21", "lastmod": "2023-10-23 20:58:16", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part E - Accelerograms IIE071 through IIE085", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIE071 IIE072 IIE073 IIE074 IIE075 IIE076 IIE077 IIE078 IIE079 IIE080 IIE081 IIE082 IIE083 IIE084 IIE085", "note": "PS 227 470/AS", "abstract": "The records analyzed in this Volume III, Part E, are the corrected accelerogram data of Volume II, Part E, Report No. EERL 73-50, and appeared in their uncorrected form in Volume I, Part E, Report No. EERL 71-22.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-83", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-83", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7383.pdf", "url": "https://authors.library.caltech.edu/records/1ydmy-p1r05/files/7383.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/0qj5w-cg721", "eprint_id": 26291, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:29", "lastmod": "2023-10-23 20:58:03", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part B - Accelerograms IIB021 through IlBO40", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIB021 IIB022 IIB023 IIB024 IIB025 IIB026 IIB027 IIB028 IIB029 IIB030 IIB031 IIB032 IIB033 IIB034 IIB035 IIB036 IIB037 IIB038 IIB039 IIB040", "note": "PB 220 161", "abstract": "This issue, Volume II, Part B, Report EERL 72-50, continues the accelerograms recorded between 1933 and 1968, including particularly El Centro, California, 1934; Helena, Montana, 1935; Seattle and Olympia, Washington, 1949; Olympia, Washington, 1965; and the Cholame -Shandon array, 1966. The uncorrected versions of the accelerograms in this issue appeared in Volume I, Part B, Report EERL 70-21.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-72-50", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-72-50", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7250.pdf", "url": "https://authors.library.caltech.edu/records/0qj5w-cg721/files/7250.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/48499-83239", "eprint_id": 26420, "eprint_status": "archive", "datestamp": "2023-08-19 08:19:19", "lastmod": "2023-10-24 16:18:55", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wood-John-Holm", "name": { "family": "Wood", "given": "John H" } } ] }, "title": "Earthquake-induced soil pressures on structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1973", "abstract": "The earthquake-induced pressures on soil-retaining structures are investigated. The study was motivated by the lack of suitable earthquake design data for relatively rigid structures on firm foundations in situations where the foundation, structure and retained soil remain essentially elastic.\n\nPressures and forces on the walls of a number of idealized wall-soil problems are analyzed. The solutions obtained are evaluated for a range of the important parameters to give results useful for design. In the idealized problems the soil is represented by an elastic layer of finite length bonded to a rigid foundation or rock layer. The wall or structure is represented by a rigid element resting on the rock layer and is permitted to undergo rotational deformation about the base. The mass or moment of inertia of the structure and its rotational stiffness are included as parameters in the idealization. Static and dynamic solutions are obtained using both analytical and finite element methods. Solutions are evaluated for the assumption of perfectly rigid behavior of the wall. The general solution for the deformable wall case was developed by superposition of the solution for the perfectly rigid case and solutions derived for displacement forcing of the wall structure.\n\nThe assumption of linear elastic behavior of the wall- soil system is likely to be approximately satisfied in situations where a building or other large civil engineering structure is founded on firm soil or rock strata. In contrast to the linearly elastic assumption made in this study, the commonly used Mononobe-Okabe method employs the assumption of sufficiently large wall deformations to induce a fully plastic stress condition in the soil. It was concluded that both the elastic theory and the Mononobe-Okabe method have valid applications in the design of wall structures subjected to earthquake motions, but that because of significant differences in the solutions obtained from each method, care is required in selecting the most appropriate method for a particular situation.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7305.pdf", "url": "https://authors.library.caltech.edu/records/48499-83239/files/7305.pdf" }, "pub_year": "1973", "author_list": "Wood, John H" }, { "id": "https://authors.library.caltech.edu/records/yf7mf-1rg06", "eprint_id": 26250, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:16", "lastmod": "2023-10-23 20:57:08", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part D - Accelerograms IID056 through IID070", "ispublished": "unpub", "full_text_status": "public", "keywords": "IID056 IIDO57 IID058 IIDO59 IIDO60 IIDO61 IIDO62 IIDO63 IIDO64 IIDO65 IIDO66 IIDO67 IIDO68 IIDO69 IIDO70", "note": "PB 227 469/AS", "abstract": "This is the fourth report of a series presenting earthquake response spectrum curves calculated from corrected ground accelerograms. In the Preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for users of the data. For each earthquake accelerogram, two spectrum plots are given - relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this Volume III, Part D, are the corrected accelerograrn data of Volume II, Part D, Report No. EERL 72-52, and appeared in their uncorrected form in Volume I, Part D, Report No. EERL 71-21.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-82", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-82", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7382.pdf", "url": "https://authors.library.caltech.edu/records/yf7mf-1rg06/files/eerl7382.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/dkg3z-cbv94", "eprint_id": 26348, "eprint_status": "archive", "datestamp": "2023-08-19 08:18:58", "lastmod": "2023-10-24 16:16:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Udwadia-F-E", "name": { "family": "Udwadia", "given": "F. E." } }, { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "The Fourier transform, response spectra and their relationship through the statistics of oscillator response", "ispublished": "unpub", "full_text_status": "public", "note": "PB 220 458", "abstract": "The concept of the Damped Fourier Transform (D. F. S.) has been developed through an understanding of the nature of the response of a damped oscillator to input ground accelerations. It has been shown that such a transform serves as a lower bound to the corresponding damped velocity spectrum curves.\n\nA review of the statistics of the maxima of a random function has been done and its application to the determination of response spectrum estimates has been studied. Such simple statistical estimates have been found to be very useful in improving our physical understanding of response spectra.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7301.pdf", "url": "https://authors.library.caltech.edu/records/dkg3z-cbv94/files/7301.pdf" }, "pub_year": "1973", "author_list": "Udwadia, F. E. and Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/2yc8m-96z52", "eprint_id": 26287, "eprint_status": "archive", "datestamp": "2023-09-14 22:31:00", "lastmod": "2023-10-23 20:57:54", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part F - Accelerograms IIF086 through IIF105", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIF086 IIF087 IIF088 IIF089 IIF090 IIF091 IIF092 IIF093 IIF094 IIF095 IIF096 IIF097 IIF098 IIF099 IIF100 IIF101 IIF102 IIF103 IIF114 IIF", "note": "PB 227 471/AS", "abstract": "This is the sixth report of a series presenting earthquake response spectrum curves calculated from corrected ground accelerograms. In the Preface to the first part, Volume III, Part A, Report No. EERL 72-80, there is a summary of response spectrum techniques in earthquake engineering which is available as background material for users of the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The records analyzed in this Volume III, Part F, are the corrected accelerogram data of Volume II, Part F, Report No. EERL 73-51, and appeared in their uncorrected form in Volume I, Part F, Report No. EERL 71-23.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-84", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-84", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7384.pdf", "url": "https://authors.library.caltech.edu/records/2yc8m-96z52/files/7384.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/t222d-37084", "eprint_id": 26282, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:19", "lastmod": "2023-10-23 20:57:43", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part C - Accelerograms IIC041 through IIC055", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIC041 IIC042 IIC043 IIC044 IIC045 IIC046 IIC047 IIC048 IIC049 IIC050 IIC051 IIC052 IIC053 IIC054 IIC055", "note": "PB 220 162", "abstract": "The first set of twenty corrected earthquake accelerograms was published in September 1971, as Volume II, Part A, Report EERL 71-50, the first report of the Volume II series. That issue also contained introductory material and background information describing the types of corrections used. The corresponding uncorrected data appeared earlier in Volume I, Part A, Report EERL 70-20. Both of these reports, containing references related to the records themselves and the various procedures, should be referred to by all users of the data. This issue, Volume II, Part C, Report EERL 72-51, is the first report containing the accelerograms obtained during the San Fernando Earthquake of February 9, 1971 and includes 42 seconds of the Pacoima Dam record, six sections containing aftershocks recorded during the subsequent six-minute operation, and records from the Holiday Inn at 8244 Orion Boulevard, the Kajima Building at 250 East First Street and the Union Bank at 445 Figueroa Street. The uncorrected versions of the accelerograms in this issue appeared earlier in Volume I, Part C, Report EERL 71-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-72-51", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-72-51", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7251.pdf", "url": "https://authors.library.caltech.edu/records/t222d-37084/files/7251.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/0z0vh-tmf14", "eprint_id": 26332, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:10", "lastmod": "2023-10-23 20:59:22", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part E - Accelerograms IIE071 through IIE085", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIE071 IIE072 IIE073 IIE074 IIE075 IIE076 IIE077 IIE078 IIE079 IIE080 IIE081 IIE082 IIE083 IIE084 IIE085", "note": "PB 229 240/AS", "abstract": "This is fifth of a series of reports presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. Volume IV, Part A,\nReport No. EERL 72-100, included an introduction summarizing Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For\neach earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part E, appeared in Volume II, Part E, Report No. EERL 73-50. Their uncorrected versions were published in Volume I, Part E, Report No. EERL 72-22.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-103", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-103", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "73103.pdf", "url": "https://authors.library.caltech.edu/records/0z0vh-tmf14/files/73103.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/k979q-t7728", "eprint_id": 26304, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:19", "lastmod": "2023-10-23 20:58:32", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part F - Accelerograms IIF086 through IIF105", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIF086 IIF087 IIF088 IIF089 IIF090 IIF091 IIF092 IIF093 IIF094 IIF095 IIF096 IIF097 IIF098 IIF099 IIF100 IIF101 IIF102 IIF103 IIF104 IIF105", "note": "PB 224 977/AS", "abstract": "This issue, Volume II, Part F, Report No. EERL 73-51 continues with the accelerograms obtained during the San Fernando Earthquake of February 9, 1971 and includes one record from each of the following: the CMD Building in Vernon, the Orange County Engineering Building in Santa Ana, the Municipal Services Building at 633 East Broadway in Glendale, the Southern California Edison Company in Colton, Ft. Tejon, the Pearblossom Pumping Plant, the Oso Pumping Plant in Gorman, and the UCLA Reactor Lab in Los Angeles, and three records each from the buildings at 808 S. Olive, 2011 Zonal, 120 N. Robertson, and 646 S. Olive, all in Los Angeles. The uncorrected versions of the accelerograms in this issue appeared earlier in Volume I, Part F, Report EERL 71-23.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-51", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-51", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7351.pdf", "url": "https://authors.library.caltech.edu/records/k979q-t7728/files/7351.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/drhhd-cmg72", "eprint_id": 26419, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:51", "lastmod": "2023-10-23 20:59:50", "type": "monograph", "metadata_visibility": "show", "title": "Research papers submitted to Fifth World Conference on Earthquake Engineering, Rome, Italy 25-29 June 1973", "ispublished": "unpub", "full_text_status": "public", "note": "PB 220 431", "abstract": "The papers in this report were prepared for presentation at the Fifth World Conference on Earthquake Engineering (5WCEE) and will, in due course, appear in the Proceedings of that conference. Because of requests for copies of the papers, they have been printed in this Caltech report form.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7302.pdf", "url": "https://authors.library.caltech.edu/records/drhhd-cmg72/files/7302.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/s94bm-j5e22", "eprint_id": 26249, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:08", "lastmod": "2023-10-23 20:57:06", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part B - Accelerograms IIB021 through IIB040", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIB021 IIB022 IIB023 IIB024 IIB025 IIB026 IIB027 IIB028 IIB029 IIB030 IIB031 IIB032 IIB033 IIB034 IIB035 IIB036 IIB037 IIB038 IIB039 IIB040", "note": "PB 220 837", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-100", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-100", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl73100.pdf", "url": "https://authors.library.caltech.edu/records/s94bm-j5e22/files/eerl73100.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/q2apc-f2k38", "eprint_id": 26251, "eprint_status": "archive", "datestamp": "2023-09-14 22:28:24", "lastmod": "2023-10-23 20:57:11", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part G - Accelerograms IIG106 through IIG114", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIG106 IIG107 IIG108 IIG109 IIG110 IIG111 IIG112 IIG113 IIG114", "note": "PB 231 224/AS", "abstract": "This is one of a series of reports presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. Volume IV, Part A, Report No. EERL 72-100, included an introduction summarizing Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given - a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Part G, appeared in Volume II, Part G, Report No. EERL 73-52. Their uncorrected versions were published in Volume I, Part G, Report No. EERL 72-20.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-105", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-105", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl73105.pdf", "url": "https://authors.library.caltech.edu/records/q2apc-f2k38/files/eerl73105.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/f4jxw-nz058", "eprint_id": 26302, "eprint_status": "archive", "datestamp": "2023-09-14 22:33:05", "lastmod": "2023-10-23 20:58:27", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part N - Accelerograms IN185 through IN197, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IN185 IN186 IN187 IN188 IN189 IN190 IN191 IN192 IN193 IN194 IN195 IN196 IN197 71.066 71.067 71.068 71.084 71.085 71.086 71.119 71.129 71.130 71.131 71.140 71.141 71.229", "note": "PB 223 023", "abstract": "This issue continues the San Fernando accelerograms and contains thirteen records consisting of one each from the following locations: Carbon Canyon Dam in Brea, Whittier Narrows Dam in Whittier, San Antonio Dam in Upland, 2516 Via Tejon in Palos Verdes Estates, San Juan Capistrano, Long Beach State College in Long Beach, Anza Post Office in Anza, and three each from buildings located at 1880 Century Park East, and 2500 Wilshire Boulevard in Los Angeles.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-72-27", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-72-27", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7227.pdf", "url": "https://authors.library.caltech.edu/records/f4jxw-nz058/files/7227.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/7geqa-nbf78", "eprint_id": 26422, "eprint_status": "archive", "datestamp": "2023-08-19 08:19:25", "lastmod": "2023-10-24 16:18:59", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irvine-Hilary-Max", "name": { "family": "Irvine", "given": "Hilary Max" } } ] }, "title": "The Veracruz earthquake of 28 August 1973", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - 7306.pdf
", "abstract": "The earthquake, which caused widespread damage in parts of the States of Puebla and Veracruz in southeast Mexico, registered 7. 0 on the Richter Magnitude Scale, according to the Caltech Seismological Laboratory. The earthquake occurred at 3:51 (local time) on the morning of 28 August 1973. The center of destructive shaking was in the vicinity of Serdan in the State of Puebla (19N97W).\n\nThe National Earthquake Information Service reports the earthquake as occurring at 09:50:41.6 GMT with the instrumental epicenter at 18.275N96.584W, and the hypocenter at a depth of approximately 100km. The most seismic region of Mexico is along the southwest coast. Earthquakes in the region of Orizaba have been relatively infrequent; the most recent serious ground shaking occurred June 17, 1928 when a magnitude 7. 8 shock had its epicenter at 16N98W, some 250km south of Serdan. However, large earthquakes 100-300km south of Serdan have occurred relatively frequently.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7306.pdf", "url": "https://authors.library.caltech.edu/records/7geqa-nbf78/files/7306.pdf" }, "pub_year": "1973", "author_list": "Irvine, Hilary Max" }, { "id": "https://authors.library.caltech.edu/records/j718t-6ef68", "eprint_id": 26349, "eprint_status": "archive", "datestamp": "2023-09-14 22:37:38", "lastmod": "2023-10-23 20:59:46", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part Q - Accelerograms IQ233 through IQ243, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IQ233 IQ234 IQ235 IQ236 IQ237 IQ238 IQ239 IQ240 IQ241 IQ242 IQ243 71.162 71.163 71.164 71.165 71.166 71.167 71.168 71.169 71.170 71.171 71.172", "note": "PB 232 315/AS", "abstract": "This issue continues the San Fernando accelerograms and contains eleven records consisting of two records from 9100 Wilshire Boulevard in Beverly Hills and three records each from the buildings at 14724 Ventura Boulevard and 800 W. First Street in Los Angeles, and 1760 N. Orchid Avenue in Hollywood.", "date": "1973-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1973.EERL-73-22", "official_url": "https://resolver.caltech.edu/CaltechEERL:1973.EERL-73-22", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7322.pdf", "url": "https://authors.library.caltech.edu/records/j718t-6ef68/files/7322.pdf" }, "pub_year": "1973" }, { "id": "https://authors.library.caltech.edu/records/vqdvq-syj31", "eprint_id": 26298, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:30", "lastmod": "2023-10-23 20:58:18", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part I - Accelerograms 1I128 Through 1I140, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "1I121 1I122 1I123 1I124 1I125 1I126 1I127 1I128 1I129 1I130 1I131 1I132 1I133 1I134 1I135 1I136 1I137 1I138 1I139 1I140 71.087 71.088 71.089 71.121 71.120 71.122 71.126 71.127 71.128 71.135 71.136 71.137 71.230", "note": "PB 213 422", "abstract": "This issue continues the San Fernando accelerograms and contains thirteen records consisting of three each from buildings at the following addresses: 435 Oakhurst Avenue and 420 North Roxbury Drive in Beverly Hills; 1800 Century Park East and 15910 Ventura Boulevard in Los Angeles, and the record from the Borrego Springs Fire Department.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-22", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-22", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7222.pdf", "url": "https://authors.library.caltech.edu/records/vqdvq-syj31/files/7222.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/b9y85-8pv73", "eprint_id": 26280, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:06", "lastmod": "2023-10-23 20:57:38", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Part A - Accelerograms IIA001 through IIA020", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIA001 IIA002 IIA003 IIA004 IIA005 IIA006 IIA007 IIA008 IIA009 IIA010 IIA011 IIA012 IIA013 IIA014 IIA015 IIA016 IIA017 IIA018 IIA019 IIA020", "note": "PB 212 603", "abstract": "This is the first volume of a series presenting Fourier amplitude spectra for earthquake ground motions and for structural response accelerations. An introduction summarizes Fourier spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum-plots are given a Fourier amplitude spectrum versus frequency on a linear scale, and a log-spectrum, log-frequency plot. In the series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. For buildings for which simultaneous basement and upper floor accelerograms are available, building transfer functions are also plotted. The earthquakes in Volume IV, Part A, match the uncorrected accelerogram data of Volume I, the corrected accelerogram data of Volume II, and the response spectrum plots of Volume III.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-100", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-100", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "72100.pdf", "url": "https://authors.library.caltech.edu/records/b9y85-8pv73/files/72100.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/1fs20-dw853", "eprint_id": 26413, "eprint_status": "archive", "datestamp": "2023-08-19 07:47:59", "lastmod": "2023-10-24 16:18:43", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wood-John-Holm", "name": { "family": "Wood", "given": "John H" } } ] }, "title": "Analysis of the earthquake response of a nine-story steel frame building during the San Fernando earthquake", "ispublished": "unpub", "full_text_status": "public", "note": "PB 215 823", "abstract": "A study has been made of the earthquake response of the ninestory steel frame Building 180, located at the C.I.T. Jet Propulsion Laboratory, Pasadena, during the San Fernando earthquake of February 9, 1971. The study was motivated by the likelihood that an earthquake similar to the February 9, 1971, shock could occur close to the JPL grounds with consequent very strong ground shaking. It was, therefore, judged desirable to make a thorough study of the response of the building to the moderately strong ground shaking during the February 9, 1971 event. The analysis throws light on the actual dynamical properties of the building during the earthquake, and also demonstrates that it is possible to make accurate calculations of building motions during earthquakes when the ground motion is specified.\n\nMethods of evaluating the lower mode periods and damping ratios from the earthquake records are described and these values are compared with values obtained by dynamic testing before and after the earthquake and with the periods computed from structural models of the building. Although no structural damage, as a result of the earthquake motions, was detected, and computed stresses in the frame were less than yield stresses, the ambient test periods after the earthquake were approximately 1016 higher than the pre-earthquake test values. The maximum periods during the earthquake were found to be about 30% higher than the post-earthquake ambient test values, and it is believed that this significant increase was mainly the result of the non-linear behavior of the concrete encased steel columns. The periods computed from the structural models based on two different assumptions regarding the influence of the composite concrete agreed within 5% of the postearthquake ambient test results and within 10% of the earthquake periods.\n\nThe model roof acceleration responses were computed using the recorded base motions as inputs. Good agreement was obtained between the recorded and computed roof responses confirming that the elastic response computation method currently used in the earthquake design of buildings gives satisfactory stress predictions.\n\nA stress analysis of the lower stories of the model gave a maximum total steel stress during the earthquake of 34 Kips/in2. This maximum value occurred in the second story columns and was computed by adding to the gravity load stresses the root- mean- square sum of the two horizontal earthquake stress components.\n\nThe Fourier amplitude spectra of the recorded horizontal base motions were found to contain peaks corresponding closely with a number of the lower mode natural frequencies. A study was undertaken to determine whether these peaks could have resulted from soil-structure interaction. It was concluded that soil-structure interaction would be unlikely to have produced significant changes to the horizontal freefield motions. The influence of soil- structure interaction in the vertical direction was found to be rather more significant, producing a peak and a dip in the Fourier amplitude spectrum close to the fundamental vertical frequency.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7204.pdf", "url": "https://authors.library.caltech.edu/records/1fs20-dw853/files/7204.pdf" }, "pub_year": "1972", "author_list": "Wood, John H" }, { "id": "https://authors.library.caltech.edu/records/k56rr-dda74", "eprint_id": 26443, "eprint_status": "archive", "datestamp": "2023-09-14 22:38:01", "lastmod": "2023-10-23 20:59:52", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part G - Accelerograms IG106 through IG114", "ispublished": "unpub", "full_text_status": "public", "keywords": "IG106 IG107 IG108 IG109 IG110 IG111 IG112 IG113 IG114 71.018 71.019 71.022 71.023 71.032 71.031 71.038 71.040 71.064", "note": "PB 211 357", "abstract": "The first set of twenty uncorrected digitized earthquake accelerograms was published in July 1969 as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. , which should be referred to by all users of the data. The San Fernando Earthquake provided records of sufficient importance that the original plan was interrupted after two parts, and Part C contained the first of the San Fernando Earthquake accelerograms. This issue continues the San Fernando accelerograms and contains nine records consisting of six from the California Institute of Technology campus and the Jet Propulsion Laboratory, the basement and forty-second story record of a Los Angeles building, and the record from Palmdale", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-20", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-20", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7220.pdf", "url": "https://authors.library.caltech.edu/records/k56rr-dda74/files/7220.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/rvdjv-nwh78", "eprint_id": 26412, "eprint_status": "archive", "datestamp": "2023-08-19 07:47:54", "lastmod": "2024-01-13 05:31:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Udwadia-F-E", "name": { "family": "Udwadia", "given": "F. E." } } ] }, "title": "Investigation of earthquake and microtremor ground motions", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1972: PB 212 853\n\nAccepted Version - 7202.pdf
", "abstract": "The nature of strong earthquake ground shaking has been investigated based on a study of 15 accelerograms recorded at El Centro in southern California. It is concluded that the characteristics of the source mechanism and the transmission path play a dominant role in determining the details of strong ground shaking at the site. No local site periodicities could be clearly identified, which suggests that source and transmission path effects overshadow the influence of local site conditions.\n\nThe method of using microtremor measurements to determine local site characteristics has been tested by direct comparison with strong motion measurements. Microtremor ground motions were recorded at five sites in the El Centro area and measurements were repeated at three of these sites after a period of 24 hours. These low amplitude ground motions have been found to be widely different from the motions caused by strong earthquake ground shaking. Their nonstationary nature over a period of a day or so makes the interpretation of such data from a single microtremor measurement very unreliable. It has been concluded that these microtremor ground motions are forced oscillations of the ground caused by nearby sources of excitation. The microtremor acceleration spectra do not indicate prominent peaks that could be correlated with local site conditions. At this site the use of microtremor measurements to define local subsoil conditions would evidently not be feasible.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7202.pdf", "url": "https://authors.library.caltech.edu/records/rvdjv-nwh78/files/7202.pdf" }, "pub_year": "1972", "author_list": "Udwadia, F. E." }, { "id": "https://authors.library.caltech.edu/records/wtskb-6c412", "eprint_id": 26411, "eprint_status": "archive", "datestamp": "2023-08-19 07:47:49", "lastmod": "2023-10-24 16:18:39", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Dynamics of building-soil interaction", "ispublished": "unpub", "full_text_status": "public", "note": "PB 209 666", "abstract": "In this study of the dynamics of building-soil interaction, the soil is modeled by a linear elastic half-space, and the building structure by an n-degree-of-freedom oscillator. Both earthquake response and steady-state response to sinusoidal excitation are examined. By assuming that the interaction system possesses n + 2 significant resonant frequencies, the response of the system is reduced to the superposition of the responses of damped linear oscillators subjected to modified excitations. The results are valid even though the interaction systems do not possess classical normal modes. For the special cases of single-story systems and the first modes of n-story systems, simplified approximate formulas are developed for the modified natural frequency and damping ratio, and for the modified excitation. Example calculations are carried out by the approximate and more exact analysis for one-story, two-story and ten-story interaction systems.\n\nThe results show that interaction tends to decrease all resonant frequencies, but that the effects are often significant only for the fundamental mode for many n-story structures and are more pronounced for rocking than for translation. If the fixed-base structure has damping, the effects of interaction on the earthquake responses are not always conservative, and an increase or decrease in the response can occur, depending on the parameters of the system.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7201.pdf", "url": "https://authors.library.caltech.edu/records/wtskb-6c412/files/7201.pdf" }, "pub_year": "1972", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/ke77y-e5843", "eprint_id": 26418, "eprint_status": "archive", "datestamp": "2023-08-19 07:48:04", "lastmod": "2023-10-24 16:18:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Rapid calculation of selected fourier spectrum ordinates", "ispublished": "unpub", "full_text_status": "public", "abstract": "The use of Fourier spectrum techniques in earthquake engineering has grown rapidly in recent years because of the economy of programs using the Fast Fourier Transform (FFT) and the widespread use of Fourier techniques in other fields of engineering and science. Typically, the standard FFT programs take 2N equally spaced data points in the time domain as input and produce as output 2N-1 Fourier amplitude spectrum ordinates equally spaced in the frequency domain from 0 cps to the maximum frequency permitted by the digitization interval. By appropriate choice of filters, sampling interval and length of record, the FFT approach can be adapted to most purposes, but there is occasionally a need to calculate a few spectrum points in narrow frequency bands or to analyze, over selected frequency bands, records of longer duration than can be accommodated conveniently by standard FFT programs. The technique presented below permits such calculations to be made rapidly and accurately. In addition, the method helps in the interpretation of Fourier spectra used in earthquake engineering because it is developed from the point of view of elementary vibration theory.\n\nThe first part of the text reviews the relation between the response of an undamped, single degree-of- freedom oscillator subjected to the same accelerogram. This review shows that the calculation of the Fourier amplitude and phase spectrum ordinates is equivalent to finding the potential and kinetic energies of an undamped oscillator at the end of the excitation. The analysis is then extended to include an associated free vibration problem useful in the interpretation of Fourier spectra.\n\nThe next portion of the study shows that these final response values can be calculated rapidly and accurately by reducing the accelerogram, regardless of length, to an equivalent excitation with a duration of one natural period, and by further reduction to two excitations - one for displacement and one for velocity - of only one-quarter period duration. The response of the oscillator to the shortened excitations can then be calculated by standard methods. The next section is devoted to the development of a subroutine for calculating ordinates of Fourier amplitude spectra by this approach, and to the presentation of examples of its use. The study concludes with a discussion of possible applications and extensions of the method.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7205.pdf", "url": "https://authors.library.caltech.edu/records/ke77y-e5843/files/7205.pdf" }, "pub_year": "1972", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/5ckc6-4d602", "eprint_id": 26330, "eprint_status": "archive", "datestamp": "2023-09-14 22:35:56", "lastmod": "2023-10-23 20:59:18", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part F - Accelerograms IF086 through IF105, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IF086 IF087 IF088 IF089 IF090 IF091 IF092 IF093 IF094 IF095 IF096 IF097 IF098 IF099 IF100 IF101 IF102 IF103 IF104 IF105 71.100 71.101 71.102 71.247 71.103 71.104 71.105 71.106 71.107 71.111 71.112 71.113 71.114 71.115 71.116 71.142 71.143 71.144 71.146 71.147", "note": "PB 210 619", "abstract": "This issue continues the San Fernando accelerograms,and contains twenty records consisting of three records each from four buildings and eight ground level records. Some comments on these records and their digitizations follow.\nIF086. Vernon. CMD Building. The complete record of 78 seconds was digitized.\nIF087. Santa Ana. Orange County Engineering Building. The complete record of 81 seconds was digitized.\n\nIF088. Glendale. 633 E. Broadway, Municipal Services Building.\nThe complete record of 44 seconds was digitized. An aftershock triggered the instrument a second time and on some early versions of this record the two triggerings were run together as one record of considerably longer length. In this issue the aftershock is not included, but will appear as a separate record at some later date.\n\nIF089, 90, 91. 808 South Olive St. Street, 4th and 8th Levels.\nAll records continued for 2-1/4 minutes but were digitized for 59 seconds by which time the first aftershock had diminished.\n\nIF092, 93, 94. 2011 Zonal. Basement, 5th and 9th Floors. All records were digitized out to the end at 34 seconds. The instruments on the 5th and 9th floors several times responded with a very high frequency, about 80 cps, lightly damped oscillation not associated with the usual building acceleration record. This particular vibration mode of the instrument is probably initiated by an impact loading on the structure near the instrument. Such impacts arise from dislodged material or equipment, or safety devices operating in elevator mechanisms. Through these sections of the record, usually lasting one or two seconds, the true acceleration curve was assumed to pass through the center of the high frequency record.\nIF095, 96, 97. 120 North Robertson. Sub-basement, 4th and 9th Floors. The 4th floor record was digitized to 59-1/2 seconds and the other two to the record end at 67 seconds. High frequency instrument oscillations were recorded on the upper floors in this building, as in the above building at 2011 Zonal. The particular instrument on the 4th floor had a large amplitude at this frequency and consequently the selection of the central curve in this portion was more difficult than in the 9th floor record.\nIF098, 99, 100. 646 South Olive. Basement, 4th Floor and Roof. The complete 56 second records were digitized.\nIF101. Southern California Edison Co., Colton. This was a poor record, thoroughly over-exposed at between 9 and 11 seconds, where digitizing stopped.\nIF102. Fort Tejon The complete record of 10-1/2 seconds was digitized.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-71-23", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-71-23", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7123.pdf", "url": "https://authors.library.caltech.edu/records/5ckc6-4d602/files/7123.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/bmstw-tw923", "eprint_id": 26315, "eprint_status": "archive", "datestamp": "2023-09-14 22:34:21", "lastmod": "2023-10-23 20:58:50", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part H - Accelerograms IH115 through IH127, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "note": "PB 211 781 IH115 IH116 IH117 IH118 IH119 IH120 IH121 IH122 IH123 IH124 IH125 IH126 IH127 71.024 71.026 71.025 71.039 71.037 71.041 71.071 71.083 71.082 71.133 71.134 71.132 71.228", "abstract": "This issue continues the San Fernando accelerograms and contains thirteen records consisting of three each from buildings at the following addresses: 15250 Ventura Boulevard and 8639 Lincoln Avenue in Los Angeles, 900 South Fremont Avenue, Alhambra, 2600 Nutwood Avenue, Fullerton, and the basement record from the San Diego Gas and Electric Building.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-21", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-21", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7221.pdf", "url": "https://authors.library.caltech.edu/records/bmstw-tw923/files/7221.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/khqwn-6y323", "eprint_id": 26283, "eprint_status": "archive", "datestamp": "2023-09-14 22:30:28", "lastmod": "2023-10-23 20:57:45", "type": "monograph", "metadata_visibility": "show", "title": "Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part A - Accelerograms IIA001 through IIA020", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIA001 IIA002 IIA003 IIA004 IIA005 IIA006 IIA007 IIA008 IIA009 IIA010 IIA011 IIA012 IIA013 IIA014 IIA015 IIA016 IIA017 IIA018 IIA019 IIA020", "note": "PB 212 602", "abstract": "This is the first volume of a series presenting earthquake response spectrum curves calculated from corrected ground accelerograms. An introduction summarizes response spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum plot is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The earthquakes in part A match the uncorrected accelerogram data of volume I and the corrected accelerogram data of volume II.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-80", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-80", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7280.pdf", "url": "https://authors.library.caltech.edu/records/khqwn-6y323/files/7280.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/b55nb-ff707", "eprint_id": 26299, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:38", "lastmod": "2023-10-23 20:58:21", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part J - Accelerograms IJ141 through IJ152, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IJ141 IJ142 IJ143 IJ144 IJ145 IJ146 IJ147 IJ148 IJ149 IJ150 IJ121 IJ152 71.152 71.065 71.012 71.009 71.027 71.028 71.030 71.070 71.074 71.073 71.224 71.225", "note": "PB 213 423", "abstract": "This issue continues the San Fernando accelerograms and contains twelve records consisting of three each from buildings at 15107 Vanowen Street and 616 Normandie Avenue in Los Angeles; four records from the Lake Hughes Array in southern California; and two from Terminus Dam in central California.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-23", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-23", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7223.pdf", "url": "https://authors.library.caltech.edu/records/b55nb-ff707/files/7223.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/z4agr-eax30", "eprint_id": 26279, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:59", "lastmod": "2023-10-23 20:57:36", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part L - Accelerograms IL166 through IL175, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "71.036, 71.042, 71.O29, 71.094,71.095, 71.099, 71.139, 71.138, 71.117, 71.118 IL166 IL167 IL168 IL169 IL170 IL171 IL172 IL173 IL174 IL175", "note": "PB 215 639", "abstract": "The first set of twenty uncorrected digitized earthquake accelerograms was published in July 1969 as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc., which should be referred to by all users of the data. The San Fernando Earthquake provided records of sufficient importance that the original plan was interrupted after two parts and Part C contained the first of the San Fernando Earthquake accelerograms. This issue continues the San Fernando accelerograms and contains ten records consisting of four from 1888 Century Park East in Los Angeles, three from 3838 Lankershim Boulevard in Los Angeles, two from 945 Tiverton Avenue in Los Angeles and one record from the Southern California Edison Nuclear Power Plant in San Onofre, California.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-25", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-25", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "eerl7225.pdf", "url": "https://authors.library.caltech.edu/records/z4agr-eax30/files/eerl7225.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/sr0sq-55q17", "eprint_id": 26300, "eprint_status": "archive", "datestamp": "2023-09-14 22:32:47", "lastmod": "2023-10-23 20:58:23", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - Uncorrected accelerograms; Part K - Accelerograms IK 153 Through IK 165, Accelerograms from the San Fernando, California, earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "keywords": "IK153 IK154 IK155 IK156 IK157 IK158 IK159 IK160 IK161 IK162 IK163 71.217 71.218 71.021 71.020 71.076 71.078 71.080 71.081 71.219 71.220 71.221 71.222 71.223", "note": "PB 213 424", "abstract": "This issue continues the San Fernando accelerograms and contains thirteen records consisting of two each from buildings at the following addresses: 420 South Grand Avenue and 750 Garland Avenue in Los Angeles, four records from Maricopa Array and five records from the Isabella Dam.", "date": "1972-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1972.EERL-72-24", "official_url": "https://resolver.caltech.edu/CaltechEERL:1972.EERL-72-24", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7224.pdf", "url": "https://authors.library.caltech.edu/records/sr0sq-55q17/files/7224.pdf" }, "pub_year": "1972" }, { "id": "https://authors.library.caltech.edu/records/2d3na-tnz11", "eprint_id": 26266, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:16", "lastmod": "2023-10-23 20:57:24", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part D - accelerograms ID056 through ID070", "ispublished": "unpub", "full_text_status": "public", "keywords": "ID056 ID057 ID058 ID059 ID060 ID061 ID062 ID063 ID064 ID065 ID066 ID067 ID068 ID069 ID070 71.007, 71.156, 71.155, 71.006, 71.003,71.017, 71.013, 71.015, 71.010, 71.046, 71.045, 71.044, 71.050, 71.051, 71.052", "note": "PB 209 529", "abstract": "The first set of twenty uncorrected digitized earthquake accelerograms was published in July, 1969, as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc., which should be referred to by all users of the data.\nThe San Fernando Earthquake provided records of sufficient importance that the original plan was interrupted after two parts, and Part C contained the first of the San Fernando Earthquake accelerograms.\nThis issue continues the San Fernando accelerograms and contains fifteen records consisting of three records each from four buildings, two ground level records at the Hollywood Storage Building and the record from the Old Ridge Route at Castaic. Some comments on these records follow.\nID056. Castaic, Old Ridge Route. At 0.97 seconds after triggering the drive mechanism malfunctioned briefly and the film was stationary for a short length of time with the recording light on. The actual time is indicated by asterisks in the computer printout and by arrows in the computer plot. The lost portion of trace can be estimated to be one to two seconds long for the following reasons. The gap between the time marks is normally 0.5 seconds, but the particular gap spanning the missing part measures only 0.3 seconds. Hence at least 0.2 seconds is missing. In addition, at least one of the time marks occurred during the pause, so that the possible lengths of the pause are 0.7, 1.2, 1.7, 2.2, ... seconds. The maximum amplitudes of the missing traces can be ascertained from the thickness of the recorded vertical line for two of the three traces and these are less than the peak amplitudes occurring during the following one or two seconds. The changes in density along the recorded vertical line indicate that not a great many of the large oscillations of the trace took place during the pause and that a duration of 1.2 seconds is realistic. Also the records from the Lake Hughes Array Stations 4 and 12, within 26 km of Castaic, and a similar distance from the epicenter, 25-29km, indicate that the strong motion portion in this vicinity was only a few seconds in duration. These complete records show a marked similarity to that portion of the Castaic record outside the lost part, further confirming that not more than one or two seconds was lost. As another means of estimating the time lost, a laboratory test was made on the Castaic accelerograph in which the recording paper was held stationary for various time intervals with the recording light on, The intensities of the resulting traces were compatible with the above estimates.\n\nID057, 58, Hollywood Storage Building, Basement and P. E, Lot. The total record length for the main shock is included.\nID059, 60, 61, 1900 Avenue of the Stars, Subbasement, 9th and 21st Floors. The instrument on the 9th floor several times responded with a very high frequency, 80 - 100 cps, lightly damped oscillation, probably initiated by an impact loading on the structure near the instrument. Such impacts arise from dislodged material or equipment, or safety devices operating in elevator mechanisms. These were not digitized as part of the project. The instrument on the 21st floor operated for the same 58 - 60 seconds as the other two, but the first 11 seconds were not recorded.\n\nID062, 63, 64. 1640 South Marengo Street, lst, 4th and 8th Floors. The 1st and 8th floor records were digitized to 54 seconds, by which time the first aftershocks had diminished. The 4th floor record was digitized to 98 seconds, for the total length of the record.\n\nID065, 66, 67. 3710 Wilshire Blvd, Basement 5th and 10th Floors. The instrument on the 10th floor faces a different direction from the other two instruments and the component directions are therefore different.\n\nID068, 69, 70. 7080 Hollywood Blvd., Basement 6th and 12th Floors. The total record length for the main shock is included. As in previous reports the printout and plots contain asterisks and arrows, respectively, indicating where the record was shifted in the digitizer.\nTwo further reports (see References) have been issued at the California Institute of Technology describing the San Fernando Earthquake. \"The Engineering Features of the San Fernando Earthquake, February 9, 1971\" contains preliminary studies of some of the more important and interesting engineering features of the earthquake. The various chapters were prepared by staff and students working in Earthquake Engineering within the Division of Engineering and Applied Science. \"Strong Motion Instrumental Data on the San Fernando Earthquake of February 9, 1971\", a joint report with the Seismological Field Survey of the National Oceanic and Atmospheric Administration, U. S. Department of Commerce, presents an overall picture of the instrumentation results, updating and bringing together a number of preliminary reports issued by both the Earthquake Engineering Research Laboratory and the Seismological Field Survey. An account is given there of the performance of the Southern California strong motion networks, including the seismoscope results. Both of these reports are available from the National Information Service for Earthquake Engineering at the California Institute of Technology.\nWe should like once again to express our gratitude to personnel from the Jet Propulsion Laboratory who earlier assisted so capably on the digitizing, and to our regular digitizers and assistants, students and otherwise, for their conscientious work. We would like to acknowledge the general support of the Earthquake Research Affiliates, the generous grants from the National Science Foundation and the cooperation of the Seismological Field Survey of the National Oceanic and Atmospheric Administration.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-21", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-21", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "EERL-71-21.pdf", "url": "https://authors.library.caltech.edu/records/2d3na-tnz11/files/EERL-71-21.pdf" }, "pub_year": "1971" }, { "id": "https://authors.library.caltech.edu/records/p178z-tgj84", "eprint_id": 26331, "eprint_status": "archive", "datestamp": "2023-09-14 22:36:04", "lastmod": "2023-10-23 20:59:20", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part A - Accelerograms IIA001 through IIA020", "ispublished": "unpub", "full_text_status": "public", "keywords": "IIA001 IIA002 IIA003 IIA004 IIA005 IIA006 IIA007 IIA008 IIA009 IIA010 IIA011 IIA012 IIA013 IIA014 IIA015 IIA016 IIA017 IIA018 IIA019 IIA020", "note": "PB 208 283", "abstract": "None available.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-50", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-50", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "7150.pdf", "url": "https://authors.library.caltech.edu/records/p178z-tgj84/files/7150.pdf" }, "pub_year": "1971" }, { "id": "https://authors.library.caltech.edu/records/xejd5-yhm51", "eprint_id": 26522, "eprint_status": "archive", "datestamp": "2023-08-19 07:22:14", "lastmod": "2023-10-24 16:22:20", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "Strong-Motion Instrumental data on the San Fernando Earthquake of Feb. 9, 1971", "ispublished": "unpub", "full_text_status": "public", "abstract": "The San Fernando Earthquake of February 9, 1971 occurred virtually at the center of the Southern California strong-motion earthquake instrumentation network, and provided an unprecedented amount of valuable data on strong earthquake -generated ground motions, This data will be of key significance in interpreting the severe damage to many modern engineering structures which occurred, and marks a major development in the field of earthquake engineering.\nIt was evident immediately after the event that the problems of recovering field records, of processing the information, and of disseminating the results as quickly and as widely as possible would severely tax the available resources. Fortunately, the close cooperation which had been built up over the years between the Seismological Field Survey of the U. S. Department of Commerce and the Earthquake Engineering Research Laboratory of the California Institute of Technology provided an operating group which could be quickly expanded to meet the challenge.\nIn the days and weeks following the earthquake, each of these organizations issued numerous preliminary reports aimed at the quickest possible distribution of information. The present report up-dates and brings together a number of these initial releases, along with much new material. It is hoped that in this way a more complete picture of the overall instrumentation results can be presented in one convenient place. The report also makes available for the first time a complete description of the Southern California networks, and a\ndetailed account of the performance of these networks during the earthquake,\nA notable feature of the present report is the reproduction in accurate scale form of the complete set of seismoscope records obtained during the earthquake. These seismoscope records offer an unparalleled picture of the complexity of the pattern of ground shaking throughout the Southern California region.\nThe primary purpose of the present compilation is to make available the basic data itself, and no attempt has been made to add interpretive material. Many interpretive studies have, of course, already been made, and the full exploitation of this basic data to increase our knowledge of earthquake engineering will no doubt go on for a number of years.\nIn reporting the accelerograph measurements, numerous examples of accelerograms have been given, and samples of standard data processing procedures leading to digitized print-outs and calculated velocity and displacement curves, and response spectrum curves, have been included. The complete set of accelerograms in computer -plotted form, along with the digital print-outs, are being issued by the Earthquake Engineering Research Laboratory of the California Institute of Technology as a part of the series \"Strong-Motion Earthquake Accelerograms - Digitized and Plotted Data.\" The first volume devoted to the San Fernando earthquake has already been issued as Vol. 1, part C, Report No. EERL 71-20. These volumes of digitized accelerograms will be followed during the next year by additional volumes containing integrated ground velocity and displacement curves, and response spectrum curves, which will be prepared for all of the records obtained during the San Fernando earthquake.\nThe existence of this unusually complete ground motion data is a tribute to the cooperative efforts of a large number of people over a period of many years. Many of the individuals involved have been named in the acknowledgements included in the separate sections. Hundreds of individual accelerograph and seismoscope owners have pooled their resources to make the Southern California region the best instrumented area in the world for strong earthquake ground motion investigations. A complete list of organizations, building owners, and others who deserve thanks for making possible the acquisition and the operation of the instruments would be an imposing indication of the extent of the cooperative effort involved. Special mention should be -made of the very important contributions of the late John C. Monning, former general manager and superintendent of the Department of Building and Safety of the City of Los Angeles. It was Mr, Monning's vision and foresight, implemented with great energy and patience, which resulted in the code requirements for accelerographs in tall buildings which made this earthquake the most extensive structural dynamic test of full-scale buildings ever carried out. His colleagues and successors in the Department of Building and Safety have carried this work forward in a very effective manner, and have thus played a key role in the development of the accelerograph network.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL.1971.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL.1971.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1971.pdf", "url": "https://authors.library.caltech.edu/records/xejd5-yhm51/files/Hudson_1971.pdf" }, "pub_year": "1971", "author_list": "Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/maen8-rrm56", "eprint_id": 26416, "eprint_status": "archive", "datestamp": "2023-08-19 07:21:44", "lastmod": "2024-01-13 05:31:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Adu-Randolph-Ademola", "name": { "family": "Adu", "given": "Randolph Ademola" } } ] }, "title": "Response and failure of structures under stationary random excitation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1971: PB 205 304", "abstract": "The response of simple structural systems to stationary random excitation is considered under two criteria of failure. When failure is specified as the crossing of a maximum tolerable threshold by the response, the reliability of a structure is commonly measured by means of response spectra. These give the expected maximum value of the response parameter for a given excitation level. The statistical variations in these spectra are obtained here for viscously damped linear and elastoplastic single-degree of freedom systems by electronic analog simulation. The results obtained are compared with approximate statistical analyses; for example, the threshold crossing statistics of narrow-band oscillators. It is concluded that such methods give satisfactory, but conservative, estimates of the mean spectral values. It is significant that all the spectra obtained showed a very wide distribution about the mean. This was also true of the Fourier amplitude spectrum of the excitation.\n\nFor responses that are so large that structures actually collapse, the linear model was replaced by an elastoplastic system, and the effect of gravity on the collapse time was considered. Experimental simulation showed that the structural response in this case is essentially that of a linear oscillator with yielding occurring at intermittent intervals. Gravity acts to increasingly bias this yielding in one direction, eventually causing instability in the system. Collapse of the system was sensitive to the distribution of peaks in the excitation and it was found that the wide dispersion in the collapse time can be reasonably represented by a Gamma distribution function.\n\nAn analytic method for estimating the mean collapse time was derived by considering the energy distribution of the excitation and its effect on the yielding of the structure. The response process was thus modelled by that of an equivalent linear oscillator whose baseline is biased by the yielding in the structure. It was concluded that this procedure gives a good estimate of the failure time for excitations strong enough to cause failure in less than 20 seconds.\n\nA two- degree of freedom elastoplastic hysteretic system with gravity was also simulated. In a certain sense, the qualitative behavior is similar to that of the single-degree of freedom system. It was thus possible to estimate the failure time of the structure from that of a single-degree of freedom system once the transmission of vibration is accounted for by considering a linear two-degree of freedom system.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7103.pdf", "url": "https://authors.library.caltech.edu/records/maen8-rrm56/files/7103.pdf" }, "pub_year": "1971", "author_list": "Adu, Randolph Ademola" }, { "id": "https://authors.library.caltech.edu/records/c4ak4-bae61", "eprint_id": 26407, "eprint_status": "archive", "datestamp": "2023-08-19 07:21:33", "lastmod": "2024-01-13 05:30:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bielak-Jacobo", "name": { "family": "Bielak", "given": "Jacobo" } } ] }, "title": "Earthquake response of building-foundation systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1971: PB 205 305\n\nAccepted Version - 7104.pdf
", "abstract": "The influence of a deformable foundation on the response of buildings to earthquake motion is examined. The study is divided into two parts; the vibration of the base of the building on the foundation medium, and the response of the whole building-foundation system.\n\nStudied first are the forced horizontal, rocking and vertical harmonic oscillations of a rigid disc bonded to an elastic half-space, which is considered as a mathematical model for the soil. The problem, formulated in terms of dual integral equations, is reduced to a system of Fredholm integral equations of the second kind. For the limiting static case these equations yield a closed form solution in agreement with that obtained by others.\n\nUsing the force-deflection relations for the base, the equations of motion of linear building-foundation systems are solved by both direct and transform methods. It is shown that, under assumptions which appear to be physically reasonable, the earthquake response of the interaction system reduces to the linear superposition of the responses of damped, linear one-degree-of-freedom oscillators subjected to modified excitations. This result is valid even for systems that do not possess classical normal modes. Explicit approximations in terms of the parameters of the system are obtained for the dynamic properties of the one-degree-of -freedom oscillator which is equivalent to a single story building -foundation system. For multi-story buildings it is shown that the effect of an elastic foundation, as measured by the change in the natural frequencies of the building, is negligible for modes higher than the first for many types of building structures.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7104.pdf", "url": "https://authors.library.caltech.edu/records/c4ak4-bae61/files/7104.pdf" }, "pub_year": "1971", "author_list": "Bielak, Jacobo" }, { "id": "https://authors.library.caltech.edu/records/d6sex-fw741", "eprint_id": 26440, "eprint_status": "archive", "datestamp": "2023-08-19 07:21:53", "lastmod": "2023-10-24 16:19:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Engineering features of the San Fernando earthquake of February 9, 1971", "ispublished": "unpub", "full_text_status": "public", "note": "PB 202 550", "abstract": "Because of its consequences, the San Fernando earthquake was a major earthquake from the engineering point of view, even though it was only a moderate shock in seismological terms. As a result of the many effects of the earthquake, a large number of detailed studies and reports will be forthcoming from a wide variety of sources, and the papers collected in this volume are only preliminary studies of some of the more important and interesting engineering features of the earthquake. The papers were prepared by staff and students working in earthquake engineering within the Division of Engineering and Applied Science at the California Institute of Technology.\n\nThe timely financial support of the Engineering Division of the National Science Foundation and the Earthquake Research Affiliates of the California Institute of Technology in conducting the research and preparing this report is gratefully acknowledged.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7102.pdf", "url": "https://authors.library.caltech.edu/records/d6sex-fw741/files/7102.pdf" }, "pub_year": "1971", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/b4sdc-mah64", "eprint_id": 26408, "eprint_status": "archive", "datestamp": "2023-08-19 07:21:38", "lastmod": "2023-10-24 16:18:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } }, { "id": "Udwadia-F-E", "name": { "family": "Udwadia", "given": "F. E." } }, { "id": "Brady-A-G", "name": { "family": "Brady", "given": "Arthur Gerald" } } ] }, "title": "High frequency errors and instrument corrections of strong-motion accelerograms", "ispublished": "unpub", "full_text_status": "public", "note": "PB 205 369", "abstract": "A study of high-frequency errors present in digitized accelerograms and an analysis of the distribution of unequally spaced, hand-digitized data indicates that the Fourier content of digitized accelerogram. data may be accurate up to about 25 cps.\n\nTwo methods for accelerometer instrument correction are described: (1) a direct numerical differentiation of recorded accelerograms from which high-frequency digitization errors have been filtered out and (2) an ideal \"mathematical accelerometer\" with a natural frequency significantly higher than the natural frequency of the recording instrument. Although both methods give good results, the first one is recommended for the standard use.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7105.pdf", "url": "https://authors.library.caltech.edu/records/b4sdc-mah64/files/7105.pdf" }, "pub_year": "1971", "author_list": "Trifunac, Mihailo D.; Udwadia, F. E.; et el." }, { "id": "https://authors.library.caltech.edu/records/4gt9n-m8v50", "eprint_id": 26267, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:25", "lastmod": "2023-10-23 20:57:26", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part E - Accelerograms IE071 through IE085", "ispublished": "unpub", "full_text_status": "public", "keywords": "IE071 IE072 IE073 IE074 IE075 IE076 IE077 IE078 IE079 IE080 IE081 IE082 IE083 IE084 IE085", "note": "PB 209 749", "abstract": "The first set of twenty uncorrected digitized earthquake \naccelerograms was published in July, 1969 as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. , which should be referred to by all users of the data.\n\nThe San Fernando Earthquake provided records of such importance that the original plan was interrupted after two parts, and Part C contained the first of the San Fernando Earthquake accelerograms.\n\nThis issue continues the San Fernando accelerograms and contains fifteen records consisting of three records each from four buildings, two records from Santa Felicia Dam and a ground record from Wheeler Ridge. Some comments on these records follow.\n\nIE071. Wheeler Ridge. The entire 30 second record was digitized. The time marks functioned for only two seconds, and therefore the paper speed was calculated from an average value during the preceding calibration test.\n\nIE072, 73, 74. 4680 Wilshire Boulevard, Basement, 3rd and 6th Floors. There is a hesitation of 0.2 second duration in the record in the basement during the first second of operation. Aligning this record with the other two may consequently require considerable care.\n\nIE075, 76, 77. 3470 Wilshire Boulevard, Sub-basement, 5th and 11th Floors. The sub-basement record was digitized on a different machine from that at Caltech and only 44 seconds could be handled. The upper floor records were digitized to 64 seconds, just short of the total record length.\n\nIE078, 79, 80. Los Angeles Water and Power Building, Basement, 7th and 15th Floors. The basement record was digitized to 57 seconds by which time the first aftershock had diminished. The upper floor records were digitized for a further 15 seconds.\n\nIE081, 82, Santa Felicia Dam, Outlet Works and Crest. Both records have been digitized the total length.\n\nIE082, 83, 84. 3407 Sixth Street, Basement, 4th Floor and Penthouse. The entire 60 second records were digitized.\n\nAs in previous reports the printout and plots of those records that require shifting in the digitizer contain asterisks and arrows, respectively, indicating where such shifts occurred.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-22", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-22", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "EERL-71-22.pdf", "url": "https://authors.library.caltech.edu/records/4gt9n-m8v50/files/EERL-71-22.pdf" }, "pub_year": "1971" }, { "id": "https://authors.library.caltech.edu/records/d0cyb-exf18", "eprint_id": 26268, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:36", "lastmod": "2023-10-23 20:57:29", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part C - Accelerograms IC041 through IC055", "ispublished": "unpub", "full_text_status": "public", "keywords": "IC041 IC042 IC043 IC044 IC045 IC046 IC047 IC048 IC049 IC050 IC051 IC052 IC053 IC054 IC055", "note": "PB 204 364", "abstract": "The first set of 20 uncorrected digitized earthquake accelerograms was published in July, 1969 as Volume I, Part A of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. which should be referred to by all users of the data.\nParts A and B have contained accelerograms from earthquakes dating from March 10, 1933, and are a portion of a complete series planned in 1969 covering all the important accelerograms to that time. The San Fernando Earthquake, however, provided more than twice as many records as previously available. In view of the importance of this earthquake, it was felt that we should interrupt the original plan and issue this and succeeding Parts containing San Fernando Earthquake accelerograms, before returning to the original series.\nThe record from Pacoima Dam has received a great deal of attention. Included here are 42 seconds containing the main shock and the first clearly identifiable aftershock, together with six further aftershocks. Because of its importance and the high trace amplitudes involved, the Pacoima record was digitized from the original paper film. All the remaining paper film records were digitized from contactnegatives. Although most reproductions of the Pacoima record indicate some dim portions of the trace, the original trace was clearly distinguishable with no ambiguity. The special problems of this particular accelerogram are treated in the paper by Trifunac and Hudson listed in the references on page 5.\nThe six portions of the Pacoima record containing the aftershocks have the following starting times, measured in seconds after the start of the main shock trace: 52. 6, 69. 6, 104. 6, 162. 0, 230. 1, and 309. 1 sec. These starting times are indicated by arrows on the reproduction of the Pacoima record appearing on page 6.\nRecords from-buildings or arrays containing more than one instrument are included together in one. Part where possible. Part C contains records from Holiday Inn at 8244 Orion Blvd., L. A. , the Kajima Building at 250 E. First St., L. A. , (three records each) and the Union Bank at 445 Figueroa St., L. A. (two records.).\nAs in previous reports the printout and plots contain asterisks and arrows, respectively, .indicating where the record was shifted in the digitizer when required.\nWe should like to express our gratitude to personnel from the Jet Propulsion Laboratory who have assisted so capably on the digitizing: Miriam Blount, Jeannyne Gunkel, Jo Jean Kos, Carolyn Level and Florence Sims. In. addition we should like to thank our regular digitizers and assistants, students and otherwise, for their conscientious. work: N. R. Bacheliri, D. A. Blount, Esther Dizack, R. C. Dullien, H. H. Kwai, H. H. Law, V. W: Lee, M. Y. -C. Ngan, W. J. Raymond and K. K. Tung. We would also like to acknowledge the general support off the Earthquake Research Affiliates. The whole program has at all stages been conducted through the generous help of grants from the National Science Foundation, and- we have enjoyed the close cooperation of the staff of the Seismological Field Survey of the National Oceanic and Atmospheric Administration.", "date": "1971-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1971.EERL-71-20", "official_url": "https://resolver.caltech.edu/CaltechEERL:1971.EERL-71-20", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "EERL-71-20.pdf", "url": "https://authors.library.caltech.edu/records/d0cyb-exf18/files/EERL-71-20.pdf" }, "pub_year": "1971" }, { "id": "https://authors.library.caltech.edu/records/tbfsc-jge26", "eprint_id": 26406, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:29", "lastmod": "2023-10-24 16:18:29", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Ambient vibration test of a thirty-nine story steel frame building", "ispublished": "unpub", "full_text_status": "public", "abstract": "No abstract available.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-02", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-02", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7002.pdf", "url": "https://authors.library.caltech.edu/records/tbfsc-jge26/files/7002.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/2b5g4-55q02", "eprint_id": 26269, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:44", "lastmod": "2023-10-23 20:57:31", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part B - Accelerograms IB21 through IB40", "ispublished": "unpub", "full_text_status": "public", "keywords": "IB21 IB22 IB23 IB24 IB25 IB26 IB27 IB28 IB29 IB30 IB31 IB32 IB33 IB34 IB35 IB36 IB37 IB38 IB39 IB40", "note": "PB 196 823", "abstract": "The first set, of 20 uncorrected digitized earthquake accelerograms was published in July, 1969, as Volume I, Part. A of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. which should be referred to by all users of the data.\nOver 500 copies of the first report were distributed to investigators all over the world, and we are grateful for the many comments we have received which will guide our future efforts. The format used in presenting the data seems to have received a general approval, and we have accordingly continued it without change for the present report.\nTwo records in this report need special mention. IB21 Vernon, California, 3-10-33, 1754PST, was digitized in two parts. The first part was an enlarged print of the faintly recorded strong motion portion, and the second part was the normal translucent contact print. An overlap was included. After scaling the first digitized portion to be the same as the second, the two portions were joined by least square fitting the overlapped portion.. The usual procedure for uncorrected data was then followed. The other record was IB33 Cholame-Shandon, California, No. 2, 6-27-66, 2026PST. The accelerograph component in the N25W direction malfunctioned, leaving no suitable recorded trace, and the printout and plot are consequently excluded.\nOn some of the early records with no fixed trace incorporated we have been able to consider the time mark trace as an approximation to a fixed trace, for all three components. Digitization of a particular place in each time mark then allowed use of the (x, y) coordinates for a fixed trace, and the x-coordinate for a time mark.\nThe printout and plots as before contain asterisks and arrows, respectively, indicating where the record was shifted in the digitizer when required.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-21", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-21", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "EERL-70-21.pdf", "url": "https://authors.library.caltech.edu/records/2b5g4-55q02/files/EERL-70-21.pdf" }, "pub_year": "1970" }, { "id": "https://authors.library.caltech.edu/records/vjcq4-xwr62", "eprint_id": 26271, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:00", "lastmod": "2023-10-24 16:15:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } }, { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "Laboratory evaluations and instrument corrections of strong-motion accelerograms", "ispublished": "unpub", "full_text_status": "public", "abstract": "Since the first strong-motion accelerographs for the measurement of the ground motion associated with destructive earthquakes appeared in the early 1930's there has been a continual development of instruments and data handling techniques. These developments have resulted in improved field reliability, increased frequency response range, better resolution and accuracy, and reduced costs. As new instrument types appear it is necessary to carry out comprehensive programs of laboratory and field evaluation to ensure adequate performance capabilities.\n\nThe advent of high speed digital computer systems has completely altered data processing procedures associated with strongmotion instrumentation. Modern digitization and digital filtering techniques, for example, have made it possible to use new approaches to transducer design, and to the optimal retrieval of information from instrument records.\n\nThe Earthquake Engineering Research Laboratory of the California Institute of Technology considers the continued reliable operation, expansion, and data processing functions of a network of strong-motion accelerographs to be one of the key requirements of earthquake engineering research. To this end, this laboratory has for many years conducted numerous studies and research programs aimed at improvements in all aspects of this subject. In cooperation with the Seismological Field Survey of the U. S. Coast and Geodetic Survey, the Caltech group has been engaged in accelerograph design, testing, network design and installation, accelerogram digitizing and corrections, and the use of accelerograms for structural response determinations.\n\nThe present report brings together a number of special studies related to accelerograph evaluations and data processing, which may be of interest to others engaged in instrument development or in the use of accelerograph records. It is our feeling that the best use can be made of the basic data only by those persons thoroughly familiar with the details of instrument design, and the special problems that may be associated with both the basic measurements themselves and with the handling and interpretation of the data. Some repetition of test method descriptions has been retained to ensure a reasonable independence of the various sections.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-04", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-04", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "eerl7004.pdf", "url": "https://authors.library.caltech.edu/records/vjcq4-xwr62/files/eerl7004.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D. and Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/8e3dv-wbe16", "eprint_id": 26404, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:19", "lastmod": "2023-10-24 16:18:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Wind and microtremor induced vibrations of a twenty-two story steel frame building", "ispublished": "unpub", "full_text_status": "public", "abstract": "A method of structural testing using wind and micro-tremor induced vibrations is outlined for a twenty-two story steel frame building. The results for the translational and torsional frequencies agree well with the independent determinations of the frequencies and modes obtained from vibration generator resonance tests of the same building. It is concluded that the method of structural testing based on the ambient induced vibrations can give good estimates of the frequencies and modes of vibration of building structures.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-01", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-01", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7001.pdf", "url": "https://authors.library.caltech.edu/records/8e3dv-wbe16/files/7001.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/0mt37-p2x90", "eprint_id": 26346, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:04", "lastmod": "2023-10-24 16:16:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Response envelope spectrum and interpretation of strong earthquake ground motion", "ispublished": "unpub", "full_text_status": "public", "abstract": "A multiple filter technique is developed using a single degree of freedom lightly damped oscillator as a narrow band-pass filter. It provides for a physically simple approach to the analysis of accelerograph records from the point of view of structural engineering.\n\nThe analysis of several typical accelerograph records indicates that a significant portion of strong earthquake ground motion consists of surface waves. It is concluded that the duration of intense shaking will be determined predominantly by the dispersion properties of the ground.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-06", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-06", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7006.pdf", "url": "https://authors.library.caltech.edu/records/0mt37-p2x90/files/7006.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/bs3f0-dgb73", "eprint_id": 26417, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:33", "lastmod": "2023-10-24 16:18:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keightley-W-O", "name": { "family": "Keightley", "given": "W. O." } } ] }, "title": "A strong-motion accelerograph array with telephone line interconnections", "ispublished": "unpub", "full_text_status": "public", "abstract": "A basic problem in the use of self-triggered strong-motion accelerographs has been the reduction of starting time in the interests of recording as much of the early portion of the record as possible. It has been suggested, for example, that a short memory should be built into the instrument, perhaps by means of a tape loop, so that the very beginning of the ground motion could be recovered. Such expedients have the difficulty of requiring a more complicated, and hence more expensive and perhaps less reliable device.\n\nThe system described in Part I below solves this problem by interconnecting for common start several accelerographs distributed over a five -mile region. The interconnection was accomplished using commercial telephone lines. In this way, whichever instrument first receives a ground motion sufficient to start, will also start some of the other instruments a second or so before the strong ground motion arrives. It is believed that in this way the advantage of early starting can be achieved for some instruments without a significant increase in instrument complexity.\n\nOnce the interconnection for common start had been made, it was decided to additionally provide a common timing signal to the several recorders so that propagation of seismic disturbances might be studied. Part II of this report describes circuitry which provides common timing and also disconnects recorders from the interconnecting circuit after 8-1/2 minutes of continuous operation. The latter provision prevents exhaustion of film and batteries in the event of a short circuit of the telephone wires. The circuitry for common timing and short circuit protection has not yet been installed on the five-mile circuit, but has been built and tested only in the laboratory, with resistances used to represent the telephone wires.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-05", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-05", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7005.pdf", "url": "https://authors.library.caltech.edu/records/bs3f0-dgb73/files/7005.pdf" }, "pub_year": "1970", "author_list": "Keightley, W. O." }, { "id": "https://authors.library.caltech.edu/records/mnxy4-cps24", "eprint_id": 26521, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:59", "lastmod": "2023-10-24 16:22:18", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Heitner-K-L", "name": { "family": "Heitner", "given": "Kenneth Leon" } } ] }, "title": "Additional investigations on a mathematical model for calculation of the run-up of tsunamis", "ispublished": "unpub", "full_text_status": "public", "abstract": "Basic experimental data are presented for four tests performed on a full-scale steel-frame building: (1) Static unloading test, involving strain-gage measurements on structural members loaded by the vertical dead weight of the structure, (2) Strain-gage measurements of temperature-induced strains during a 24-hour period, (3) Strain-gage measurement of static strains caused by a lateral force applied by a cable, and (4) Dynamic resonance tests in which the structure was excited laterally by sinusoidal force generators. In connection with the interpretation of these experiments, measurements were also made of ground and structure vibrations caused by an adjacent power generation plant.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL.1970.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL.1970.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Heitner_1970.pdf", "url": "https://authors.library.caltech.edu/records/mnxy4-cps24/files/Heitner_1970.pdf" }, "pub_year": "1970", "author_list": "Heitner, Kenneth Leon" }, { "id": "https://authors.library.caltech.edu/records/6x5qr-bgm03", "eprint_id": 26347, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:09", "lastmod": "2023-10-24 16:16:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Low frequency digitization errors and a new method for zero baseline correction of strong-motion accelerograms", "ispublished": "unpub", "full_text_status": "public", "abstract": "A study of the random digitizing errors introduced by the operator indicates that these errors are relatively small in the doubleintegrated digital data up to a period of about 16 seconds for a typical accelerograph record.\n\nA new method is proposed for standard baseline correction of accelerograms. It is based on high-pass filtering of the uncorrected data. Unlike the parabolic baseline correction, the new method has well defined frequency transfer function properties which are largely independent of the record length.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-07", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-07", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7007.pdf", "url": "https://authors.library.caltech.edu/records/6x5qr-bgm03/files/7007.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/z68z2-sb548", "eprint_id": 26405, "eprint_status": "archive", "datestamp": "2023-08-19 06:58:24", "lastmod": "2023-10-24 16:18:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "On the Statistics and possible triggering mechanism of earthquakes in Southern California", "ispublished": "unpub", "full_text_status": "public", "abstract": "A statistical analysis is presented for the Southern California region, for 33 years beginning on January 1, 1934, and for all earthquakes with Richter magnitude [greater than or equal to] 3.0.\n\nA relatively general model for triggering shocks is described which admits any perturbation function which is stationary in time and has a power spectral density. The tides are considered as possible admissible perturbations, and it is shown that on the basis of the earthquake data and the model considered, they may be accepted as statistically possible triggering mechanisms for earthquakes in Southern California.", "date": "1970-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1970.EERL-70-03", "official_url": "https://resolver.caltech.edu/CaltechEERL:1970.EERL-70-03", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "7003.pdf", "url": "https://authors.library.caltech.edu/records/z68z2-sb548/files/7003.pdf" }, "pub_year": "1970", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/dv9yb-kz056", "eprint_id": 26270, "eprint_status": "archive", "datestamp": "2023-09-14 22:29:51", "lastmod": "2023-10-23 20:57:33", "type": "monograph", "metadata_visibility": "show", "title": "Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part A - Accelerograms IA1 through IA20", "ispublished": "unpub", "full_text_status": "public", "keywords": "IA1 IA2 IA3 IA4 IA5 IA6 IA7 IA8 IA9 IA10 IA11 IA12 IA13 IA14 IA15 IA16 IA17 IA18 IA19 IA20", "note": "PB 287 847", "abstract": "Preface to the Series\n\nThe object of the present series is to make available accurate digitized data prepared in a uniform way for all recorded strong-motion earthquakes. This first report is the initial step in a continuing data processing program which will ultimately include all past recorded earthquakes as well as current data as it is collected. In addition to digitized ground acceleration records, certain basic calculated information such as integrated velocity and displacement curves, response spectra, and Fourier spectra, will also be issued in a standard form. The existence of this standardized data will allow all investigators to begin with the same basic numerical data, and should thus reduce the scatter of numerical results, the meaning of which has sometimes been difficult to assess.\nIn addition to an improvement in the consistency of numerical results, several other advantages will be derived from the standardized data. (1) A number of earthquake records will be available which have not hitherto been analyzed in any form; (2) Vertical component data will be available for all earthquakes, digitized on a simultaneous time basis with the two horizontal components; (3)A small overall improvement in data accuracy will result from the inclusion of corrections for baseline distortion on the original record, and for timing mark variations; (4) Basic accelerogram data uncorrected for base line adjustments will be available for research purposes, as well as corrected data using standard adjustments.\nAccurate measurements of the ground motions of destructive earthquakes form the indispensable starting point for invesitgations in earthquake engineering. The number of such measurements that have been made in the past is unfortunately very small, and there is thus a need to extract the maximum possible information from the relatively few records that do exist.\nStarting with the first earthquake accelerogram for a destructive earthquake obtained in Long Beach, California, in 1933, the network of accelerographs maintained by the U. S. Coast and Geodetic Survey has gradually accumulated a very important series of accelerograms including some measurements of most of the strong earthquakes occurring in the Pacific Coast States since that time. Although for most of these earthquakes the number of accelerograph records is much smaller than would be desirable, the available records have formed a sound base for the development of current ideas as to the character of destructive earthquake ground motion. The number of such earthquake accelerograms now available for analysis is of the order of one hundred.\nThe importance of the work of the Seismological Field Survey of the U. S. Coast and Geodetic Survey in the development, installation, and servicing of accelerographs and in the highly efficient and reliable collection of this basic data cannot be overestimated. In addition, this group has always made available accurate copies of the original accelerograms to interested investigators throughout the world.\nThe size of the USCGS accelerograph network has gradually grown from about 40 instruments in 1935 to some 300 accelerographs in 19690 This has resulted in a gratifying increase in the number of accelerograms, but has emphasized the need for working out a more comprehensive program for the processing of this data. Both instruments and data processing methods have steadily evolved over the years since the beginning of the network, and the matter of establishing uniform procedures has now become of critical importance.\nSome of the factors which suggest that a uniform preparation of information is now essential are: (1) The basic accelerograph itself has gone through many stages of development, and the network now contains a wide variety of devices differing considerably in mechanical, electrical, and optical details. Although the basic physical parameters are approximately equivalent, there are significant differences which sometimes can be corrected for if the proper information is at hand. (2) A wide variety of recording media and record sizes are employed in the various accelerographs, and many different techniques have been used over the years to digitize the analog photographic traces for numerical work. (3) Various important earthquake accelerograms have been studied by different investigators using different interpretive techniques. In addition, various corrective methods have been employed, and it is not always clear for a given reproduced accelerogram just how the basic data has been treated. (4) As modern digital computing techniques have been developed, there has been a continuous evolution of the data processing techniques used. For example, response spectrum calculations have been carried out by desk calculators, by analog computer methods, and by digital computers. This may complicate the comparison of old spectrum curves with more recent calculations. Integrated velocity and displacement curves are well known to be particularly sensitive to this kind of computational variation. The foregoing factors, plus the fact that highly efficient digitizing and computing facilities are now available, have provided the motive for the present undertaking.\n\nThe present series will be issued in the following volumes:\n\nVolume IDigitized Accelerograms, Uncorrected, with Print-outs and Plotted Records\nVolume IIDigitized Accelerograms, Base-line corrected. Integrated Velocity and Displacement Curves\nin Plotted and Digitized Form\nVolume IIIResponse Spectrum Curves\n\nAdditional volumes now being planned will present other forms of the basic data of use in earthquake engineering such as Fourier Spectrum curves.\n\nEach volume will in turn be issued in parts A, B, C, etc., each containing 20 earthquakes. In this way it is hoped that useful information can be issued as it is prepared, without the delays associated with the completion of the whole project.\nThe project has involved close cooperation at every stage with the Seismological Field Survey of the U. S. Coast and Geodetic Survey, and the methods and formats used have been arrived at after detailed consultation with Mr. William K. Cloud, Chief of the Seismological Field Survey, and his staff.\nA work of the present type naturally involves important contributions from a large number of people. Some of these will be identified in specific sections and in the reference material. Anything like a complete list of those who have in this way earned the gratitude of future earthquake investigators is obviously impracticable here. It is a pleasure to acknowledge at this point the support of the Engineering Division of the National Science Foundation for the long-range support which makes a project of the present type possible.\n\nIntroduction to Volume I\n\nUncorrected Digitized Data - Earthquake Ground Accelerations\n\nThis volume contains the digitized accelerograms of strong earthquake ground motions as processed from records obtained from the strong-motion accelerograph network maintained by the U. S. Coast and Geodetic Survey. No base-line or instrumental corrections or adjustments have been made - the data may thus be regarded as \"uncorrected\" in the sense that no modifications have been introduced which involve any hypotheses as to the character of the ground motions or instruments involved. This digitized data is thus believed to be as close a representation of the original, raw information as it is feasible to achieve with a digital process.\nA significant feature of the compilation is the fact that uniform data processing methods have been applied to all earthquakes. These methods will now be briefly described. Additional details will be found in Appendix I, which reprints a paper presented at the Fourth World Conference on Earthquake Engineering, Santiago, Chile, in January 1969 \nAs a first step, full size contact film negatives were prepared from the original records which were recorded in the field on photographic paper. This reproduction process was carried out by the staff of the Seismological Field Survey of the U. S. Coast and Geodetic Survey in San Francisco, using the original records from the Washington Office of the USCGS. From these film negatives, contact prints were made on a frosted, translucent, Mylar-based film. Measurements have shown that these prints differ in size from the film negatives by less than\n-7-\n\n0. 1%o, and the distortion involved in going from the original paper record to the contact negative is believed to be no larger than this. The translucent film is mechanically strong, dimensionally stable, and affords excellent optical contrast for setting the cross-hairs on the digitizing machine on a back-lighted glass table. Experiments on photographic development techniques resulted in standard methods for producing an optimum balance between contrast and trace width.\nOf the approximately one hundred records available, about fourfifths were of good to excellent quality, and permit an accurate digitization with relative ease. About one-fifth are of poorer quality, requiring greater judgment and more effort in the digitizing process, but nevertheless permitting results of satisfactory overall accuracy.\nThe digitizing is performed on a Benson-Lehner 099D Datareducer unit. The cross-hairs are manually set to successive x-y coordinates on the record trace. The coordinates are converted to digital position figures by means of a magnetic readout head, and are stored in a 6-digit accumulator system from which they are automatically read out to an electric typewriter and a card punch. The maximum resolution of the system is about 800 digital counts per inch, corresponding to a least time interval on most records of 1/300 seconds. The 24 inch table length on the digitizer can accommodate 30 seconds of record at the fastest recording speeds. Most of the accelerograms could be digitized in one position on the digitizer table. For those records requiring repositioning, the points in the record at which changes have occurred are noted, using an arrow on the plotted accelerogram, and an asterisk in the print-out.\nThe records have been digitized on an unequal time basis, which has been found to give the best definition of the trace for a given number of sections and in the reference material. Anything like a complete list of those who have in this way earned the gratitude of future earthquake investigators is obviously impracticable here. It is a pleasure to acknowledge at this point the support of the Engineering Division of the National Science Foundation for the long-range support which makes a project of the present type possible.", "date": "1969-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1969.EERL-70-20", "official_url": "https://resolver.caltech.edu/CaltechEERL:1969.EERL-70-20", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "EERL-70-20.pdf", "url": "https://authors.library.caltech.edu/records/dv9yb-kz056/files/EERL-70-20.pdf" }, "pub_year": "1969" }, { "id": "https://authors.library.caltech.edu/records/53rbf-c6x55", "eprint_id": 26503, "eprint_status": "archive", "datestamp": "2023-08-19 06:20:02", "lastmod": "2023-10-24 16:21:39", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Heitner-K-L", "name": { "family": "Heitner", "given": "Kenneth Leon" } } ] }, "title": "A mathematical model for calculation of the run-up of tsunamis", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1969", "abstract": "To understand the engineering implications of possible wave run-up resulting from tsunamis, a formulation of the run-up process capable of giving quantitative answers is required. In this thesis, a new mathematical run-up model suitable for computer evaluation is proposed and tested. The two-dimensional model uses a flow constrained so that the horizontal velocity is uniform in depth. However, unlike the usual shallow water theory, the terms representing the kinetic energy of the vertical motion are retained. It is shown that this formulation allows a solitary-like wave to propagate as well as giving a more accurate indication of wave breaking. An 'artificial viscosity' term is used to allow the formation of hydraulic shocks. The effects of bottom friction are also included. The model is derived for a linear beach slope, in Lagrangian coordinates. A finite element formulation of the problem is derived that is suitable for digital computer evaluation.\nCalculations with the model agree satisfactorily with experimental results for th e run-up of solitary waves and bores. The model is used to obtain run-up data on tsunami-like waves, which show the danger of large run-up from low initial steepness waves on shallow slopes. However, the data also show that bottom friction values can significantly attenuate run-up, especially on shallow slopes.\nWaves generated by a dipole-like displacement of the simulated ocean floor show that the run-up is usually larger when the upwards displacement is nearest the beach than when the downwards displacement is nearest the beach.", "date": "1969-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1969.EERL.1969.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1969.EERL.1969.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Heitner_1969.pdf", "url": "https://authors.library.caltech.edu/records/53rbf-c6x55/files/Heitner_1969.pdf" }, "pub_year": "1969", "author_list": "Heitner, Kenneth Leon" }, { "id": "https://authors.library.caltech.edu/records/mgd31-m1766", "eprint_id": 26527, "eprint_status": "archive", "datestamp": "2023-08-19 06:20:12", "lastmod": "2023-10-24 16:22:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trifunac-M-D", "name": { "family": "Trifunac", "given": "Mihailo D." } } ] }, "title": "Investigation of strong earthquake ground motion", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1969", "abstract": "The pattern of energy release during the Imperial Valley, California, earthquake of 1940 is studied by analysing the El Centro strong motion seismograph record and records from the Tinemaha seismograph station, 546 km from the epicenter. The earthquake was a multiple event sequence with at least 4 events recorded at El Centro in the first 25 seconds, followed by 9 events recorded in the next 5 minutes. Clear P, S and surface waves were observed on the strong motion record. Although the main part of the earthquake energy was released during the first 15 seconds, some of the later events were as large as M = 5.8 and thus are important for earthquake engineering studies. The moment calculated using Fourier analysis of surface waves agrees with the moment estimated from field measurements of fault offset after the earthquake. The earthquake engineering significance of the complex pattern of energy release is discussed. It is concluded that a cumulative increase in amplitudes of building vibration resulting from the present sequence of shocks would be significant only for structures with relatively long natural period of vibration. However, progressive weakening effects may also lead to greater damage for multiple event earthquakes.\nThe model with surface Love waves propagating through a single layer as a surface wave guide is studied. It is expected that the derived properties for this simple model illustrate well several phenomena associated with strong earthquake ground motion. First, it is shown that a surface layer, or several layers, will cause the main part of the high frequency energy, radiated from the nearby earthquake, to be confined to the layer as a wave guide. The existence of the surface layer will thus increase the rate of the energy transfer into the man-made structures on or near the surface of the layer. Secondly, the surface amplitude of the guided SH waves will decrease if the energy of the wave is essentially confined to the layer and if the wave propagates towards an increasing layer thickness. It is also shown that the constructive interference of SH waves will cause the zeroes and the peaks in the Fourier amplitude spectrum of the surface ground motion to be continuously displaced towards the longer periods as the distance from the source of the energy release increases.", "date": "1969-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1969.EERL.1969.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1969.EERL.1969.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Trifunac_1969.pdf", "url": "https://authors.library.caltech.edu/records/mgd31-m1766/files/Trifunac_1969.pdf" }, "pub_year": "1969", "author_list": "Trifunac, Mihailo D." }, { "id": "https://authors.library.caltech.edu/records/v54xs-8gw79", "eprint_id": 26526, "eprint_status": "archive", "datestamp": "2023-08-19 05:59:08", "lastmod": "2023-10-24 16:22:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spencer-R-A", "name": { "family": "Spencer", "given": "Richard A" } } ] }, "title": "The nonlinear response of some multistory reinforced and prestressed concrete structures subjected to earthquake excitation", "ispublished": "unpub", "full_text_status": "public", "abstract": "The nonlinear dynamic responses of two reinforced and six prestressed concrete versions of a twenty story frame structure to a strong earthquake are found, using a step-by-step integration technique. A special model beam is used to represent the concrete members. The effects of different member properties, different amounts of hysteretic damping, and two different viscous damping mechanisms on response and energy dissipation are compared. The prestressed concrete structures have higher lateral displacements and inter-story drifts, but lower ductility requirements, and the comparative results suggest that a prestressed structure of the type analyzed could withstand a strong earthquake.", "date": "1968-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1968.EERL.1968.005", "official_url": "https://resolver.caltech.edu/CaltechEERL:1968.EERL.1968.005", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Spencer_1968.pdf", "url": "https://authors.library.caltech.edu/records/v54xs-8gw79/files/Spencer_1968.pdf" }, "pub_year": "1968", "author_list": "Spencer, Richard A" }, { "id": "https://authors.library.caltech.edu/records/2rvx3-8zc72", "eprint_id": 26524, "eprint_status": "archive", "datestamp": "2023-08-19 05:59:03", "lastmod": "2023-10-24 16:22:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peters-R-B", "name": { "family": "Peters", "given": "Rex Bredesen" } } ] }, "title": "Strong motion accelerograph evaluation", "ispublished": "unpub", "full_text_status": "public", "note": "Mechanical Engineer, 1969", "abstract": "A brief study is made of the effect of common instrument errors on the accuracy of data obtained from strong motion earthquake accelerographs. Error sources considered include zero drift, tilts, nonlinearities, cross-axis sensitivity, lack of initial conditions, noise, and time base errors. It is concluded that most data of current engineering interest are not critically affected by the level of errors found in existing accelerographs. Techniques are suggested for reducing or eliminating many of these errors by instrument design changes.\nAn experimental study is made of a new strong motion accelerograph during its engineering development. This new accelerograph is designed to record an FM analog of ground acceleration on magnetic tape, providing a record which may be rapidly and automatically converted to digital form. The accuracy limits of the accelerograph are explored and the design reasons for these limits investigated. The more significant findings maybe briefly summarized:\n\n(1) Static accuracy. The sensitivity and linearity of the instrument are found to depend critically on a series of interdependent adjustments. Reasonable care will bring errors in both of these quantities to within \u00b12% of 1/2 g full scale. Higher accuracies are possible, but require much more time and care, primarily due to the limiting effect of mechanical drift in the accelerometers.\n\n(2) Zero point drift. Uncertainties in the accelerometer zero point arise from both mechanical and electronic drifts. Long term drifts may be related to temperature or relative humidity, or may be entirely random. Short term drifts of up to 2% of full scale may occur during the course of a typical record. The total variation may be as much as \u00b1 30% of full scale for a 100 [degrees] F range of temperatures. These variations require adjustment of the data before processing, but are not sufficient to interfere with operation of the accelerograph.\n\n(3) Noise. Random noise in the system as tested amounted to 1.4% of full scale, RMS, and was mostly due to the tape recording system. By comparison with optical accelerographs, this noise figure is marginal, but acceptable, and can be improved by changes to the compensation system.\n\n(4) Timing. The advantages of an effectively continuous time base over discrete time marks were discovered and means devised to obtain such a base from the test accelerograph. This method of timing is a qualitative improvement over the best system which is practical on optical recorders. \nThe overall performance of the test accelerograph is adequate to yield acceptably accurate acceleration vs. time records and Fourier spectra within the range of frequencies which are of current engineering interest. It is able to produce useful displacement records only for periods shorter than several seconds. The reasons for this latter limitation are sufficiently fundamental that markedly superior instruments are not expected to be available within the next ten years.", "date": "1968-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1968.EERL.1968.004", "official_url": "https://resolver.caltech.edu/CaltechEERL:1968.EERL.1968.004", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Peters_1968.pdf", "url": "https://authors.library.caltech.edu/records/2rvx3-8zc72/files/Peters_1968.pdf" }, "pub_year": "1968", "author_list": "Peters, Rex Bredesen" }, { "id": "https://authors.library.caltech.edu/records/qnb4w-n7g42", "eprint_id": 26449, "eprint_status": "archive", "datestamp": "2023-08-19 05:58:49", "lastmod": "2023-10-24 16:19:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nigam-N-C", "name": { "family": "Nigam", "given": "Navin Chandra" } }, { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Digital calculation of response spectra from strong-motion earthquake records", "ispublished": "unpub", "full_text_status": "public", "abstract": "This report presents a numerical method for computing response spectra from strong-motion earthquake records. The method is based on the exact solution to the governing differential equation and gives a three to four-fold saving in computing time compared to a third order Runge-Kutta method of comparable accuracy. An analysis was made of the errors introduced at various stages in the calculation of spectra so that allowable errors could be prescribed for the numerical integration. Using the proposed method of computing or other methods of comparable accuracy, example calculations show that the errors introduced by the numerical procedures are much less than the errors inherent in the digitization of the acceleration record.\n\nIncluded as appendices to the report are computer programs in Fortran IV, with instructions for their use, for computing spectra, for correction of the baseline of the digitized record, and for the computation of ground velocity and displacement.", "date": "1968-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1968.EERL.1968.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1968.EERL.1968.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Nigam.pdf", "url": "https://authors.library.caltech.edu/records/qnb4w-n7g42/files/Nigam.pdf" }, "pub_year": "1968", "author_list": "Nigam, Navin Chandra and Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/jbatn-eye86", "eprint_id": 26509, "eprint_status": "archive", "datestamp": "2023-09-18 22:54:21", "lastmod": "2023-10-23 22:36:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "U. S. Coast and Geodetic Survey. Seismological Field Survey-", "name": { "family": "U. S. Coast and Geodetic Survey. Seismological Field Survey" } } ] }, "title": "Strong-Motion Instrumental data on the Borrego Mountain Earthquake of 9 April 1968", "ispublished": "unpub", "full_text_status": "public", "abstract": "The Borrego Mountain earthquake triggered 114 strong-motion accelerographs in the southern California region. Hitherto the maximum number of instruments in the Pacific Coast network which had simultaneously operated was 35 accelerographs during the main shock of the Kern County earthquakes of 1952.\nThe unprecedented nature of the instrumental coverage makes it desirable to ensure a prompt distribution of the complete basic data. As the first large scale test of the field installation and servicing conditions, as well as of the instruments themselves, the data are of unusual interest. Even though the large distance from the epicenter (135 miles) to the densest portion of the accelerograph network in the Los Angeles area resulted in many records of very low magnitude, significant studies of the distribution of ground motion can be made. In particular, the distribution pattern of the earthquake-triggered accelerographs gives valuable information on the characteristics and reliability of the starting devices incorporated into the instruments.\nIt will be noted that in addition to a number of important ground motion records at El Centro, San Diego, San Onofre, etc., numerous accelerograms were obtained in upper floor positions in tall buildings in the Los Angeles region. Although these records show low acceleration levels, they permit accurate determination of building response period. It will be of great interest to compare these earthquake -excited period measurements with those obtained from other structural tests and from calculations.\nBecause of the general interest in instrumental characteristics as well as in the distribution of ground motion, it has been decided to reproduce photographs of all record traces, no matter how small the indicated motions. It is realized that the small scale of many of the figures precludes their direct use for accurate measurements. It is intended that they will serve as an index to the available records, and will indicate to a prospective investigator the particular records which he might wish to obtain in the full-scale form from the U. S. Coast and Geodetic Survey. Since only a limited number of full-scale records can be so distributed, the present report should thus contribute to an optimum use of existing data-handling capabilities. . . .\n\nSince means have not yet been found to enable the Seismological Field Survey to expand its activities in the preparation and distribution of accelerograph records to the extent called for by the present size of the instrumental network, the present report is a cooperative effort with the California Institute of Technology under a grant from the Engineering Division of the National Science Foundation for basic studies in earthquake engineering.", "date": "1968-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1968.EERL.1968.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1968.EERL.1968.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "corp_creators": { "items": [ "Earthquake Engineering Research Laboratory," ] }, "primary_object": { "basename": "Borrego_1968.pdf", "url": "https://authors.library.caltech.edu/records/jbatn-eye86/files/Borrego_1968.pdf" }, "pub_year": "1968", "author_list": "U. S. Coast and Geodetic Survey. Seismological Field Survey" }, { "id": "https://authors.library.caltech.edu/records/982fj-78b31", "eprint_id": 26523, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:55", "lastmod": "2023-10-24 16:22:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nigam-N-C", "name": { "family": "Nigam", "given": "Navin Chandra" } } ] }, "title": "Inelastic interactions in the dynamic response of structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1967", "abstract": "The dynamic response of structures is examined under a general condition of loading. It is shown that the inelastic response of structures depends on the interaction between forces and displacements existing at a section during yielding. A theory of yielding is developed in terms of forces and displacements incorporating the effects of such interactions. Based on this theory, a force-displacement relationship is derived under a general condition of loading. The use of this relationship to study the response of structures is discussed and equations of motion are derived for a simple frame subjected to simultaneous base excitation along its principal directions.\nTo study the inelastic response of structures, under a general condition of loading, it is necessary to derive the equation of the yield surface in terms of forces acting at a section. For the special case of bending about the principal axes of a section, equations of yield surfaces are derived for various structural sections.\nThe response of a simple frame, subjected to sinusoidal base excitation, is obtained for elastic behavior, elasto-plastic behavior and elasto-plastic behavior with interaction. The response for these behaviors is compared and it is shown that interaction causes significant changes in the response. The response of the frame is also investigated for earthquake type excitation and a series of curves are presented to show the effect of interaction on various response parameters. Use of these curves for inelastic design of structures is indicated and the implications of the effects of interaction are examined.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.006", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.006", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Nigam_1967.pdf", "url": "https://authors.library.caltech.edu/records/982fj-78b31/files/Nigam_1967.pdf" }, "pub_year": "1967", "author_list": "Nigam, Navin Chandra" }, { "id": "https://authors.library.caltech.edu/records/m6aqh-zfp20", "eprint_id": 26519, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:49", "lastmod": "2023-10-24 16:22:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hallanger-L-W", "name": { "family": "Hallanger", "given": "Lawrence W" } } ] }, "title": "The dynamic stability of an unbalanced mass exciter", "ispublished": "unpub", "full_text_status": "public", "note": "Phd, 1967", "abstract": "The dynamic stability of single- and multi-degree-of-freedom unbalanced mass exciter systems is discussed. Previous work concerning this subject by A. Sommerfield, Y. Rocard, R. Mazet, V.0. Kononenko, Y.G. Panovko and I.I. Gubanova is summarized. A single-degree-of-freedom system consisting of a linear mechanical oscillator with a rotating unbalanced mass connected rigidly to it is defined as the basic single-degree-of-freedom system. This system is mathematically equivalent to the one used by Rocard in his analysis. The differential equations of motion for the system are obtained by using Lagrange's Equations. Global stability, stability in the sense of Laplace, is proved using Liapunov's second method. Four separate local stability analyses of this system are developed, two of which assume a constant angular velocity, [omega], of the unbalanced mass and two which allow for periodic variations in [omega]. These analyses are termed zero and first order respectively.\nThe first zero order analysis is based directly on the differential equations of motion and the zero order steady state solution. The steady state torque output of the vibration exciter motor and the steady state torque requirements of the oscillator are obtained as functions of the operating frequency. Stability is determined by examining the behavior of the system in the vicinity of the intersection points of these two functions. The second zero order analysis examines the behavior of small perturbations added to the steady state solution. The system is considered stable if these perturbations disappear with time. The first first order analysis is a perturbation type, but is based on a steady state solution which allows for periodic variations in [omega].\n \nThe second first order analysis is also based on the first order perturbed equations of motion but is a Floquet type analysis. Validity criteria for the zero and first order analyses are obtained, and the zero order region of validity is plotted graphically. A representative set of systems is analyzed numerically, and the results are presented in a figure showing the stability boundary as a function of the system parameters in non-dimensional form.\nTwo distinct types of muIti-degree-of-freedom systems are discussed. The first consists of a single oscillator mass that is free to perform planar motion. It is shown that when an unbalanced mass exciter with a uniaxial force output is mounted on the oscillator in such a way that only one mode is excited, the problem reduces to the sing le-degree-of-freedom problem. The second system consists of a series of linear sing I e-degree -of -freedom oscillators with an unbalanced mass exciter mounted on one of them. The special case of a three oscillator system with equal masses is used to demonstrate that, for systems with widely separated resonances, the \"equivalent\" singIe-degree-of-freedom analysis presented by Kononenko is valid. From these results it is concluded that, in any multi-degree-of-freedom system, an \"equivalent\" single-degree-of-freedom analysis may be used to examine the stability of the system near any resonance as long as that particular mode is the only one which is being significantly excited.\nAppendices covering the details of Rocard's analysis, and of the unbalanced mass exciters designed and built at the California Institute of Technology are included.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.005", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.005", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hallanger_1967.pdf", "url": "https://authors.library.caltech.edu/records/m6aqh-zfp20/files/Hallanger_1967.pdf" }, "pub_year": "1967", "author_list": "Hallanger, Lawrence W" }, { "id": "https://authors.library.caltech.edu/records/v4mbh-f6v92", "eprint_id": 26513, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:39", "lastmod": "2023-10-24 16:22:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuroiwa-J-H", "name": { "family": "Kuroiwa", "given": "Julio Horiuchi" } } ] }, "title": "Vibration test of a multistory building", "ispublished": "unpub", "full_text_status": "public", "note": "Civil Engineer, 1967", "abstract": "Vibration tests were performed on a 9 story reinforced concrete building with basement, in order to investigate its dynamical characteristics, by exciting the building with 2 vibration generators installed on its 9th floor.\n\nThe natural periods of vibration, the value of the damping, and the mode shapes, in the N-S and E-W directions and in torsion, were determined by measurement. Before the main part of the testing was carried out, some preliminary tests were made to check the correctness of some assumptions which would simplify the main test procedure.\n\nIt was possible to investigate in detail only the first mode of each type of motion, because of the relatively high rigidity of the building and a limitation on the maximum frequency at which the shakers could be driven.\n\nThe periods measured were quite short for a 9 story building, 0. 505 sec in the N-S direction, 0. 662 sec in the E- W direction, and 0.346 sec in torsion, and their values increased by about 3 per cent when the tests were performed at the highest force levels.\n\nThe damping, which consistently increased as the exciting force increased, varied between 0. 70 and 2. 00 per cent of the critical viscous damping. The periods and damping values were also deter- mined at very low force levels by exciting the building with a rhythmical movement of the operator's body. The periods measured in this way were slightly smaller than those found using the shakers, and the damping varied between 0.6 and 0.9 per cent of the critical viscous damping.\n\nThe mode shape did not seem to be well defined for the lower force levels, but after the force level reached a certain minimum value, the normalized mode shape remained unchanged, both with further increases in the forces, and with changes in the frequency of excitation. However, in both the N-S direction and in torsion, the horizontal displacements of the first and basement floors consistently increased, on the order of 3 per cent with respect to the displacements of the upper floors as the exciting force increased.\n\nSome aspects of the dynamical behavior of buildings, which have not been studied by other investigators in previous tests , were examined. It is a common practice in the seismic analysis of structures to assume that the floor systems act as rigid diaphragms when the building is acted upon by horizontal forces, and also to assume that the structure is fixed at the ground level. It was found that the first assumption was correct, but instead of the second it is more accurate to assume that the building is fixed at the foundation, and not at ground level.\n\nThe vibration of the ground in the vicinity of the building was also measured, together with the vibrations of the basement and first floor. It was also possible to measure the acceleration at the top of one of the units of the air conditioning equipment located on the roof. The acceleration at the top of this unit was about 8.5 times that of the roof.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Kuroiwa_1967.pdf", "url": "https://authors.library.caltech.edu/records/v4mbh-f6v92/files/Kuroiwa_1967.pdf" }, "pub_year": "1967", "author_list": "Kuroiwa, Julio Horiuchi" }, { "id": "https://authors.library.caltech.edu/records/77vh3-tg502", "eprint_id": 26512, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:33", "lastmod": "2023-10-24 16:21:58", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Husid-R", "name": { "family": "Husid", "given": "Raul" } } ] }, "title": "Gravity effects on the earthquake response of yielding structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1967", "abstract": "The effect of gravity on the earthquake response of one degree of freedom yielding structures is studied by subjecting them to earthquake-like excitation. Interest is centered on the time required for yielding to progress to the point of collapse. The results show that the effect of gravity is to increase significantly the development of permanent set over that occurring when gravity is ignored. Because the gravity effect increases as the deflection grows, the permanent set increases rapidly just prior to failure.\n\nA statistical study of the time to failure for elasto-plastic structures indicates that the average time to failure is inversely proportional to the square of the ratio of the earthquake strength to the lateral yield level of the structure, implying that an earthquake of short duration would have to possess significantly higher accelerations than a longer earthquake in order to cause failure of a given structure.\n\nIt was found that for the range of periods considered the average time to collapse for the yielding structures was independent of period. For the bilinear hysteretic structure the results show a large increase in the time of failure when the second. slope increases from zero.\n\nCalculations made with simultaneous vertical and horizontal excitation, and with recorded strong earthquake accelerograms, indicate that the thesis results , obtained from artificial earthquakes, should be applicable for strong earthquake excitation.\n\nComparison of the results with those of a one-dimensional random walk indicates that on the average a yielding structure will collapse after the input of a certain amount of energy.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.004", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.004", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Husid_1967.pdf", "url": "https://authors.library.caltech.edu/records/77vh3-tg502/files/Husid_1967.pdf" }, "pub_year": "1967", "author_list": "Husid, Raul" }, { "id": "https://authors.library.caltech.edu/records/qse9b-bw927", "eprint_id": 26505, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:18", "lastmod": "2023-10-24 16:21:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lutes-L-D", "name": { "family": "Lutes", "given": "Loren Daniel" } } ] }, "title": "Stationary random response of bilinear hysteretic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1967", "abstract": "This study of the stationary random vibration of single degree of freedom bilinear hysteretic oscillators consists of both experimental investigations and approximate analytical investigations. The experimental results are obtained from a differential analyzer electrical analog computer excited by an approximately white, Gaussian source. Measurements of mean squared levels, power spectral density and probability distribution of oscillator response are reported. The applicability of certain approximate analytical techniques is investigated by comparing analytical predictions and experimental measurements of the statistics of the response.\nThe analog computer results indicate that for a system containing viscous damping, yielding may sometimes act to increase the rms level of displacement response. In addition, the experimental results show that yielding has a marked effect on the response power spectral density, and in some instances this statistic has the general character of that for a two mode linear system. The response probability distribution is also affected by yielding and is generally not Gaussian.\nAn extension of the Krylov-Bogoliubov method of equivalent linearization and a method based on defining an approximately equivalent nonlinear nonhysteretic system are considered. The KrylovBogoliubov method gives a reasonable estimate of the rms velocity response for all cases considered but gives meaningful information about the rms displacement response only for cases of moderate nonlinearity. The second approximate method is shown to be quite good for predicting rms levels of response for cases of high yield level where the Krylov-Bogoliubov method is less successful. The application of the second method to other cases and to the problem of predicting probability distributions is also discussed.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Lutes_1967.pdf", "url": "https://authors.library.caltech.edu/records/qse9b-bw927/files/Lutes_1967.pdf" }, "pub_year": "1967", "author_list": "Lutes, Loren Daniel" }, { "id": "https://authors.library.caltech.edu/records/zq1m1-2bs96", "eprint_id": 26508, "eprint_status": "archive", "datestamp": "2023-08-19 05:36:23", "lastmod": "2023-10-24 16:21:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Giberson-M-F", "name": { "family": "Giberson", "given": "Melbourne Fernald" } } ] }, "title": "The response of nonlinear multi-story structures subjected to earthquake excitation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1967", "abstract": "The dynamic responses of a 20-story nonlinear structural frame representative of a modern high rise building are analyzed with the aid of a digital computer. Related analytical studies of continuous systems are carried out. Quantitative information is provided on the importance of a wide range of modes to the various responses of a multi-story structure during an earthquake. The effect of yielding on the response is observed. The magnitude of the structural responses are compared with common measurements of earthquake strength.\nAt the ends of each girder and column of the structural frame are yield hinges which have bilinear bending moment- rotation hysteretic characteristics. Two beam models having such characteristics are studied; one of these models can treat curvilinear hysteretic behavior. Three definitions of ductility factor are discussed, one of which is applicable to both bilinear and curvilinear hysteresis loops. In the computer program, the frame is subjected to the time history of an earthquake accelerogram, the equations of motion are stepwise integrated, and the various structural responses - displacement, bending moments, incurred yielding, etc. - are determined.\nThe agreement between the response parameters resulting from excitation by seven different earthquake ground motions indicates that these response characteristics are determined more by the properties of the structure than by the earthquake. These results throw some light on extreme value statistics of the response of yielding structures subjected to earthquakes. The characteristic patterns observed in the computed responses of the nonlinear structure can be related to analytical studies of linear elastic, shear-type, uniform and tapered continuous cantilever beams.", "date": "1967-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1967.EERL.1967.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1967.EERL.1967.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Giberson_1967.pdf", "url": "https://authors.library.caltech.edu/records/zq1m1-2bs96/files/Giberson_1967.pdf" }, "pub_year": "1967", "author_list": "Giberson, Melbourne Fernald" }, { "id": "https://authors.library.caltech.edu/records/m7q42-cmy68", "eprint_id": 26477, "eprint_status": "archive", "datestamp": "2023-08-19 05:17:49", "lastmod": "2023-10-24 16:20:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brady-A-G", "name": { "family": "Brady", "given": "Arthur Gerald" } } ] }, "title": "Studies of response to earthquake ground motion", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1966", "abstract": "A study is made of the accuracy of electronic digital computer calculations of ground displacement and response spectra from strong-motion earthquake accelerograms. This involves an investigation of methods of the preparatory reduction of accelerograms into a form useful for the digital computations and of the accuracy of subsequent digital calculations. Various checks are made for both the ground displacement and response spectra results, and it is concluded that the main errors are those involved in digitizing the original record. Differences resulting from various investigators digitizing the same experimental record may become as large as 100% of the maximum computed ground displacements. The spread of the results of ground displacement calculations is greater than that of the response spectra calculations. Standardized methods of adjustment and calculation are recommended, to minimize such errors.\nStudies are made of the spread of response spectral values about their mean. The distribution is investigated experimentally by Monte Carlo techniques using an electric analog system with white noise excitation, and histograms are presented indicating the dependence of the distribution on the damping and period of the structure. Approximate distributions are obtained analytically by confirming and extending existing results with accurate digital computer calculations. A comparison of the experimental and analytical approaches indicates good agreement for low damping values where the approximations are valid. A family of distribution curves to be used in conjunction with existing average spectra is presented. The combination of analog and digital computations used with Monte Carlo techniques is a promising approach to the statistical problems of earthquake engineering.\nMethods of analysis of very small earthquake ground motion records obtained simultaneously at different sites are discussed. The advantages of Fourier spectrum analysis for certain types of studies and methods of calculation of Fourier spectra are presented. The digitizing and analysis of several earthquake records is described and checks are made of the dependence of results on digitizing procedure, earthquake duration and integration step length. Possible dangers of a direct ratio comparison of Fourier spectra curves are pointed out and the necessity for some type of smoothing procedure before comparison is established. A standard method of analysis for the study of comparative ground motion at different sites is recommended.", "date": "1966-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1966.EERL.1966.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1966.EERL.1966.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Brady_ag_1966.pdf", "url": "https://authors.library.caltech.edu/records/m7q42-cmy68/files/Brady_ag_1966.pdf" }, "pub_year": "1966", "author_list": "Brady, Arthur Gerald" }, { "id": "https://authors.library.caltech.edu/records/7jt10-p9a47", "eprint_id": 26520, "eprint_status": "archive", "datestamp": "2023-08-19 04:56:54", "lastmod": "2023-10-24 16:22:16", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hanson-R-D", "name": { "family": "Hanson", "given": "Robert D" } } ] }, "title": "Static and dynamic tests of a full-scale steel-frame structure", "ispublished": "unpub", "full_text_status": "public", "keywords": "Blair High School Gymnasium", "abstract": "Basic experimental data are presented for four tests performed on a full-scale steel-frame building: (1) Static unloading test, involving strain-gage measurements on structural members loaded by the vertical dead weight of the structure, (2) Strain-gage measurements of temperature-induced strains during a 24-hour period, (3) Strain-gage measurement of static strains caused by a lateral force applied by a cable, and (4) Dynamic resonance tests in which the structure was excited laterally by sinusoidal force generators. In connection with the interpretation of these experiments, measurements were also made of ground and structure vibrations caused by an adjacent power generation plant.", "date": "1965-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1965.EERL.1965.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1965.EERL.1965.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hanson_1965.pdf", "url": "https://authors.library.caltech.edu/records/7jt10-p9a47/files/Hanson_1965.pdf" }, "pub_year": "1965", "author_list": "Hanson, Robert D" }, { "id": "https://authors.library.caltech.edu/records/2t0nd-8gw42", "eprint_id": 26480, "eprint_status": "archive", "datestamp": "2023-08-19 04:56:29", "lastmod": "2023-10-24 16:20:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hanson-R-D", "name": { "family": "Hanson", "given": "Robert D" } } ] }, "title": "Post-elastic dynamic response of mild steel structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1965", "abstract": "The current philosophy of earthquake resistant design is that a structure should be able to withstand an extremely strong motion earthquake without collapsing, even though a certain amount of damage is incurred. To make such a design requires a knowledge of the dynamic behavior of structures under large amplitude vibrations. The objective of the work reported here was to investigate the dynamic frequency response characteristics of a mild steel structure vibrating in the plastic range. Comparisons were made of the static, the dynamic, and the theoretical responses of the yielding structure.\nThe behavior of single-story structures having structural steel columns was investigated experimentally by means of horizontally applied forces generated by a shaking machine. The experimentally determined dynamic response showed the decrease in resonant frequency for increases in deflection amplitude which is characteristic of a \"softening spring\" type of nonlinearity. Ultraharmonic response was also observed. Under steady-state oscillations the fraction of equivalent viscous damping varied from 0.0016 at small, elastic deflections to 0.089 at large, plastic deflections. Structural deterioration was observed in both the static and dynamic experiments with a recovery of strength occurring between tests. A completely stable hysteretic loop was not attained at large deflection amplitudes, and the hysteresis loop did not become completely stable until the deflection amplitude was reduced to almost the initial yield value. However, the change in the hysteretic loop per cycle for the large deflections was small enough to permit assuming that a steady-state dynamic condition existed over a limited number of cycles.\nDiscrepancies between the theoretical and the experimental virgin force-deflection curves were found and these are shown to be the result of simplifying approximations introduced in the structural analysis. It was found that the resonant vibrational amplitude of the structure can be predicted within 20%, and the resonant natural frequency within 2 1/2%, on the basis of the static virgin force-deflection curve. For large, plastic deflections at an excitation frequency of 3 cps, it was found that the differences between the dynamic and the static hysteresis loops were less than the changes in the static loops resulting from the deterioration caused by repeated cycles of loading.", "date": "1965-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1965.EERL.1965.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1965.EERL.1965.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hanson_rd_1965.pdf", "url": "https://authors.library.caltech.edu/records/2t0nd-8gw42/files/Hanson_rd_1965.pdf" }, "pub_year": "1965", "author_list": "Hanson, Robert D" }, { "id": "https://authors.library.caltech.edu/records/p1j25-k5225", "eprint_id": 26476, "eprint_status": "archive", "datestamp": "2023-08-19 04:37:18", "lastmod": "2023-10-24 16:20:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alford-J-L", "name": { "family": "Alford", "given": "Jack L." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } }, { "id": "Martel-R-R", "name": { "family": "Martel", "given": "R. R." } } ] }, "title": "Spectrum analyses of strong-motion earthquakes", "ispublished": "unpub", "full_text_status": "public", "note": "Report on research conducted under contract with the Office of Naval Research. Originally published August 1951. This is \"revised August 1964\".", "abstract": "The problem of the dynamic response of a structure to an earthquake has been formulated in a manner which permits separation of the characteristics of particular structures from the characteristics of the earthquake. The expression involving the characteristics of the earthquake is defined as the \"spectrum\" of the earthquake and it is shown that the spectrum is simply a plot of the response of a simple oscillator versus the period of the oscillator. Eighty-eight such spectra were computed by means of an electric analog computer and are presented in this report.\n\nIt is found that damping is a very important parameter in the overall problem; relatively small amounts of damping reduce structural response sharply. It is shown that, when damping is considered, the spectra are consistent with the hypothesis of a distribution about a mean value. It is concluded that the concept of a \"dominant ground period\" is not valid for the purpose of aseismic structural design. Further research on damping in buildings is recommended, and it is proposed that the mean value of a damped spectrum be used as a quantitative measure of earthquake intensity.", "date": "1964-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1964.EERL.1964.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1964.EERL.1964.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Alford_jl_1951.pdf", "url": "https://authors.library.caltech.edu/records/p1j25-k5225/files/Alford_jl_1951.pdf" }, "pub_year": "1964", "author_list": "Alford, Jack L.; Housner, George W.; et el." }, { "id": "https://authors.library.caltech.edu/records/jp429-gjf55", "eprint_id": 26514, "eprint_status": "archive", "datestamp": "2023-08-19 04:37:32", "lastmod": "2023-10-24 16:22:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nielsen-N-N", "name": { "family": "Nielsen", "given": "Niels Norby" } } ] }, "title": "Dynamic response of multistory buildings", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1964", "abstract": "Two modern multistory buildings, one a five-story reinforced concrete building, the other a nine-story steel frame building, have been the subjects of an extensive series of dynamic tests. The vibrations of the buildings were induced by means of synchronized vibration exciters. The mathematical analysis needed in order to determine the stiffness and damping matrices from the experimentally determined modal properties of a structure has been developed.\n\nThree translational and one torsional mode of vibration of the reinforced concrete building were investigated in considerable detail. The damping in each mode and the resonant frequency was determined under various levels of excitation. Complete mode shapes were determined as well. The measurements of the resonant frequencies show a well-defined nonlinearity that can be well explained from the hysteretic material properties. The values of damping were for all modes approximately 276 with a tendency for the value of damping to increase with increasing force levels.\n\nA total of seven translational and three torsional modes of vibration of the nine-story steel frame building were investigated in detail. A mode in which the floor slabs vibrate horizontally as free-free beams was excited as well. The lowest translational modes in the two principal directions of the building had damping values of about 0.516. The second lowest translational modes had damping values of approximately 1.0016. For both buildings the damping values are considerably less than the values usually mentioned in the literature. Since most earlier tests used run-down tests rather than the steady-state tests used in the present work, comparison tests were run to explore possible differences in the test results. It was concluded that run-down tests could easily overestimate the values of damping by several hundred per cent. A new method for the measurements of natural periods of vibration of structures is proposed. The new method has several important advantages over wind-excited vibration tests which have been used extensively in the past to measure the natural periods of vibration of structures.", "date": "1964-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1964.EERL.1964.004", "official_url": "https://resolver.caltech.edu/CaltechEERL:1964.EERL.1964.004", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Nielsen_1964.pdf", "url": "https://authors.library.caltech.edu/records/jp429-gjf55/files/Nielsen_1964.pdf" }, "pub_year": "1964", "author_list": "Nielsen, Niels Norby" }, { "id": "https://authors.library.caltech.edu/records/j4wdp-gcr27", "eprint_id": 26496, "eprint_status": "archive", "datestamp": "2023-08-19 04:37:23", "lastmod": "2023-10-24 16:21:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keightley-W-O", "name": { "family": "Keightley", "given": "W. O." } } ] }, "title": "A Dynamic investigation of Bouquet Canyon Dam", "ispublished": "unpub", "full_text_status": "public", "abstract": "The work reported herein is a part of a comprehensive study of the dynamic response of full-scale structures being conducted under research grant GP-934 of the National Science Foundation. Already reported under this program are dynamic measurements on a nine-story steel frame building and a five-story reinforced concrete building. As a part of this same investigation, static and dynamic tests are under way on a steel frame structure loaded far into the plastic range, so that direct experimental evidence of the behavior of strongly nonlinear hysteretic systems will be available. These experimental studies are all accompanied by complete theoretical investigations with the object of attaining a true understanding of the relationships between analytical calculations and the actual behavior of real structures.\n\nAn investigation was made of the dynamic properties of an earth dam 200 feet high, by 1200 feet long on the crest, by 1300 feet thick at the base. The dam was excited into steady-state vibrations over the frequency range 1-1/2 to 8 cycles per second by four synchronized rotating eccentric-mass vibration exciters operating on the crest in the upstream -downstream direction. Accelerations were measured on the crest and on the downstream face to indicate the natural frequencies of the dam and to estimate the shapes of the four lowest modes of vibration. The chief results of the investigation are summarized below.", "date": "1964-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1964.EERL.1964.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1964.EERL.1964.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Keightley_1964.pdf", "url": "https://authors.library.caltech.edu/records/j4wdp-gcr27/files/Keightley_1964.pdf" }, "pub_year": "1964", "author_list": "Keightley, W. O." }, { "id": "https://authors.library.caltech.edu/records/tnvt5-kg241", "eprint_id": 26501, "eprint_status": "archive", "datestamp": "2023-09-14 19:20:46", "lastmod": "2023-10-23 20:49:47", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Kelly-M-E-J", "name": { "family": "O'Kelly", "given": "Michael Edmond James" } } ] }, "title": "Vibration of viscously damped linear dynamic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1964", "abstract": "A general theory of vibration of damped linear dynamic systems is given. The limitations on the use of the usual normal mode theory in determining the response of damped systems were first studied systematically by Caughey when he derived necessary and sufficient conditions for the uncoupling of systems in N-space. Systems which cannot be uncoupled in N-space may still be solvable by modal methods on transforming them to 2N-space and using the results of Foss. However there exist systems which cannot be solved by the usual modal techniques in either N-space or 2N-space. Such systems which include some passive physically realizable systems require the general theory for a complete determination of their motion. For weakly coupled systems the simple perturbation analysis presented gives surprisingly accurate approximations to the actual response of the systems. In any design problem questions of stability arise, particularly when dealing with nor, symmetric systems, and therefore a discussion on the stability of these systems is given.\nThe second part of the thesis is concerned with linear continuous systems. Exactly solvable continuous systems are rare and in general recourse must be had to numerical methods. The interchangeability of the differential and integral formulation of continuous systems is noted. As in the discrete systems constructive necessary and sufficient conditions are derived for a damped system to possess the same set of complete eigenfunctions as the undamped system. In the discretization of continuous systems the main problem of practical interest is the error bounds on the solution of these discrete approximations when compared to the exact solution. Unfortunately the literature is very poor in this area but what is known is applied to the systems under discussion.", "date": "1964-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1964.EERL.1964.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1964.EERL.1964.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "O'Kelly_1964.pdf", "url": "https://authors.library.caltech.edu/records/tnvt5-kg241/files/O'Kelly_1964.pdf" }, "pub_year": "1964", "author_list": "O'Kelly, Michael Edmond James" }, { "id": "https://authors.library.caltech.edu/records/q50j3-8wd57", "eprint_id": 26495, "eprint_status": "archive", "datestamp": "2023-08-19 04:17:58", "lastmod": "2023-10-24 16:21:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keightley-W-O", "name": { "family": "Keightley", "given": "W. O." } } ] }, "title": "Vibration tests of structures", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1964", "abstract": "Dynamic tests of three structures are described. In two cases linear vibration theory is applied to explain the behavior of the structures. In the third case a new method of analyzing the vibration records is introduced to define nonlinear properties of the structure.\nFree and forced vibration tests were conducted on a reservoir outlet structure consisting of a reinforced concrete tower, 149 feet in height, with a steel truss bridge, 3139 feet long, connected to the tower near the top. Measurements revealed five natural frequencies and mode shapes, and indicated the extent and significance of foundation movements. A detailed theoretical analysis of linear vibrations of the structure is carried out to show good agreement with the observations and to illustrate a general technique for the dynamic analysis of framed structures.\n\nAn earth dam 485 feet long by 60 feet in height by 450 feet thick at the base was subjected to a sinusoidal lateral exciting force at the top. Application of the theory of a truncated wedge vibrating in shear modes is made to determine an effective shear wave velocity in the earth fill and to estimate damping in the modes.\n\nA general procedure is presented for experimentally determining the restoring and dissipating functions in lumped mass. structures, linear or nonlinear. An experiment on a single degree of freedom laboratory structure with bolted joints is used to illustrate the method.\n\nThe question of instrumentation suitable for structural dynamic work is considered and recommendations are made on the basis of tests and examination of many commercially available components.", "date": "1963-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1963.EERL.1963.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1963.EERL.1963.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Keightley_1963.pdf", "url": "https://authors.library.caltech.edu/records/q50j3-8wd57/files/Keightley_1963.pdf" }, "pub_year": "1963", "author_list": "Keightley, W. O." }, { "id": "https://authors.library.caltech.edu/records/rd23h-07a68", "eprint_id": 26493, "eprint_status": "archive", "datestamp": "2023-08-19 04:17:52", "lastmod": "2023-10-24 16:21:18", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Response of simple yielding structures to earthquake excitation", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1963", "abstract": "A method is developed for generating a random process that has the pertinent properties of recorded strong-motion earthquake accelerograms. The model accelerograms are sections of a stationary, Gaussian, random process with a power spectral density found from the average undamped velocity spectrum. Eight pseudo-earthquakes of thirty seconds duration are generated on the digital computer and the velocities, displacements, and velocity spectra calculated. The average velocity spectra of the real and pseudo- earthquakes correspond closely and the velocities, displacements, and velocity spectra of the real and pseudo-earthquakes exhibit similar statistical behavior. It is concluded that the pseudo-earthquakes are satisfactory models of strong-motion earthquakes for the purposes of structural analysis.\nA general nonlinear hysteretic force-deflection relation for dynamic studies is presented. The relation is a continuous, smooth function and includes the linear and elasto-plastic relations as limiting cases. The steady-state response to sinusoidal excitation is studied in detail and the results presented. It is concluded that the hysteretic relation is general enough to be useful in structural analysis and that comparison of test results and theory may enable the dynamic force-deflection relations of real structures to be approximated.\nA class of yielding structures suitable for earthquake response studies is defined by the geometry of the hysteresis curves and the law describing yielding behavior. The general yielding relation is included in this class as are the linear, the elasto-plastic and the bilinear hysteretic relations. The equation of motion and the energy equation for the response of yielding structures to earthquake motion are examined and a typical yielding structure is subjected to the ensemble of pseudo-earthquakes.", "date": "1963-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1963.EERL.1963.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1963.EERL.1963.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Jennings_1963.pdf", "url": "https://authors.library.caltech.edu/records/rd23h-07a68/files/Jennings_1963.pdf" }, "pub_year": "1963", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/hev8h-b8m24", "eprint_id": 26492, "eprint_status": "archive", "datestamp": "2023-08-19 04:01:00", "lastmod": "2023-10-24 16:21:16", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jennings-P-C", "name": { "family": "Jennings", "given": "Paul C." } } ] }, "title": "Velocity spectra of the Mexican earthquakes of 11 May and 19 May 1962", "ispublished": "unpub", "full_text_status": "public", "abstract": "Two earthquakes of approximate Magnitude 7.0 on the Richter scale occurred near Acapulco, Mexico in May, 1962. The acceleration records were recorded on two accelerographs in Mexico City, one in the foundation of the Tower Latino Americana and the second in Alameda Park. The velocity spectra of the eight components are presented here, along with details of the calculation method and the original acceleration records in both graphical and digital form.", "date": "1962-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1962.EERL.1962.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1962.EERL.1962.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Jennings_1962.pdf", "url": "https://authors.library.caltech.edu/records/hev8h-b8m24/files/Jennings_1962.pdf" }, "pub_year": "1962", "author_list": "Jennings, Paul C." }, { "id": "https://authors.library.caltech.edu/records/jcm2f-grz65", "eprint_id": 26490, "eprint_status": "archive", "datestamp": "2023-08-19 04:00:55", "lastmod": "2023-10-24 16:21:11", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "Synchronized vibration generators for dynamic tests of full-scale structures", "ispublished": "unpub", "full_text_status": "public", "abstract": "The general considerations behind the design of a rotating\nweight sinusoidal vibration generator for dynamic studies of full-scale structures have been given in a previous report which pointed out the advantages of a system of multiple synchronized machines that would permit a distribution of exciting forces throughout a structure so as to most efficiently excite various modes of vibration.\nUnder the sponsorship of the California State Division of Architecture a set of four synchronized vibration generators has been completed and tested, and the purpose of the present report is to summarize the design information on this new system, and to give detailed operating instructions for its use.", "date": "1962-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1962.EERL.1962.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1962.EERL.1962.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1962.pdf", "url": "https://authors.library.caltech.edu/records/jcm2f-grz65/files/Hudson_1962.pdf" }, "pub_year": "1962", "author_list": "Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/bmqsk-49011", "eprint_id": 26491, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:23", "lastmod": "2023-10-24 16:21:13", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "The Dynamic response of bilinear hysteretic systems", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1961", "abstract": "A study is made of the dynamic response of one and two degree of freedom systems having a bilinear hysteretic restoring force. In the case of the one degree of freedom system exact steady state solutions are obtained for both square wave and trigonometric excitation. It is thereby shown that the system exhibits a soft type resonance and that there exists a critical level of excitation above which the system displays unbounded resonance. An approximate steady state theory for the one degree of freedom system is investigated and on the basis of this theory it is found that the system is stable and possesses a single locus of vertical tangency. The results of the exact and approximate steady state theories are supplemented by electric analog studies of both the harmonic and ultraharmonic response.\nThe response of the one degree of freedom system to transient excitation of finite duration is also examined and it is noted that certain rather general conclusions may be made about the final state of the system without reference to the specific time history of the excitation.\nA first order approximate theory for the steady state response of the two degree of freedom system is formulated and it is shown that there are two critical levels of excitation for unbounded resonance. The existence of loci of vertical tangency is demonstrated and the stability problem is treated in limiting cases. Direct numerical integration of the equations of motion is carried out for a number of specific cases as a check of the approximate theory.", "date": "1961-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1961.EERL.1961.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1961.EERL.1961.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "Iwan_1961.pdf", "url": "https://authors.library.caltech.edu/records/bmqsk-49011/files/Iwan_1961.pdf" }, "pub_year": "1961", "author_list": "Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/pr8dt-30053", "eprint_id": 26489, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:18", "lastmod": "2023-10-24 16:21:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "A New vibration exciter for dynamic tests of full scale structures", "ispublished": "unpub", "full_text_status": "public", "abstract": "Design criteria are established for a vibration exciter unit suitable for steady-state resonance tests of full-scale building structures, and several design configurations are compared. These ideas are embodied in the design of a new unit, which produces a horizontal, uni-directional sinusoidally varying force of about 1000 lb magnitude at I cycle per second, with a maximum force limit of 5000 lb. The total weight of the machine with its maximum load of eccentric weights is about 1500 lb, which can be broken down into units not exceeding 580 lb for handling and transportation. The general features of a servocontrolled electronic amplidyne speed control and D. C. drive for the vibration exciter are given. A field test of the new vibration exciter system is described, and typical results of the determination of the dynamic properties of a concrete intake tower of a dam by means of the new machine are given.", "date": "1961-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1961.EERL.1961.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1961.EERL.1961.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1961.pdf", "url": "https://authors.library.caltech.edu/records/pr8dt-30053/files/Hudson_1961.pdf" }, "pub_year": "1961", "author_list": "Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/qqfbb-9p249", "eprint_id": 26494, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:29", "lastmod": "2023-10-24 16:21:20", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keightley-W-O", "name": { "family": "Keightley", "given": "W. O." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } }, { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "Vibration tests of the Encino Dam intake tower", "ispublished": "unpub", "full_text_status": "public", "abstract": "The need for dynamic tests of full size structures has been realized for many years. The only way in which the parameters of major interest in structural dynamics problems, such as effective dynamic spring constants, energy dissipation characteristics, etc., can be determined, is by tests of actual structures under relatively high loading conditions. Such tests have very seldom been possible because of (1) the difficulty of applying dynamic loads of the required type and magnitude; (2) the difficulty of making the required measurements of dynamic structural responses; and (3) the unavailability of suitable test structures which could be loaded to the point of significant damage.", "date": "1961-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1961.EERL.1961.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1961.EERL.1961.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Keightley_1961.pdf", "url": "https://authors.library.caltech.edu/records/qqfbb-9p249/files/Keightley_1961.pdf" }, "pub_year": "1961", "author_list": "Keightley, W. O.; Housner, George W.; et el." }, { "id": "https://authors.library.caltech.edu/records/1qkas-99987", "eprint_id": 26500, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:34", "lastmod": "2023-10-24 16:21:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Merchant-H-C", "name": { "family": "Merchant", "given": "Howard C." } } ] }, "title": "Mode superposition methods applied to linear mechanical systems under earthquake type excitations", "ispublished": "unpub", "full_text_status": "public", "note": "PhD, 1961\n\nAccepted Version - Merchant_1961.pdf
", "abstract": "The determination of the maximum dynamic responses of a multidegree of freedom mechanical system under earthquake type excitation using mode superposition methods is the general problem considered. The experimental work was carried out using a special purpose electronic differential analyzer involving a three degree of freedom system, or a three mode approximation to a larger system.\nThe results indicate that a suitably weighted average of the sum of the absolute values and the square root of the sum of the squares of the individual mode contributions gives a practical design criterion for the base shear forces. For critical designs this weighted average reduces to the absolute sum of the modes, which will be close to the true value for a significantly high percentage of the cases. The base moment may be more accurately approximated than the base shear by use of the first mode alone.", "date": "1961-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1961.EERL.1961.004", "official_url": "https://resolver.caltech.edu/CaltechEERL:1961.EERL.1961.004", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Merchant_1961.pdf", "url": "https://authors.library.caltech.edu/records/1qkas-99987/files/Merchant_1961.pdf" }, "pub_year": "1961", "author_list": "Merchant, Howard C." }, { "id": "https://authors.library.caltech.edu/records/2c43q-6zd81", "eprint_id": 26479, "eprint_status": "archive", "datestamp": "2023-08-19 03:25:37", "lastmod": "2023-10-24 16:20:48", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Caughey-T-K", "name": { "family": "Caughey", "given": "Thomas Kirk" } }, { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } }, { "id": "Powell-R-V", "name": { "family": "Powell", "given": "R. V." } } ] }, "title": "The C.I.T. Mark II electric analog type response spectrum analyzer for earthquake excitation studies", "ispublished": "unpub", "full_text_status": "public", "note": "revision of a report originally issued in 1954, and deposited in this archive", "abstract": "The design of a response spectrum analyzer for earthquake excitation studies is described. Electric analog techniques are used, with a series inductance, capacitance, and resistance circuit forming a direct analog to the mechanical structure. The circuit arrangement permits a determination of system response for a sequence of periods at constant damping. Provision is made for obtaining zero damping in the circuit. An arbitrary function generator of the variable width film-photoelectric cell type is described. The results obtained with the function generator-spectrum analyzer system for a half-sine wave pulse are compared with the mathematically obtained exact answers for the zero damping case, and the accuracy of the system is shown to be satisfactory.\n\nThis is a revision of a report originally issued as the \"Sixth Technical Report\", Office of Naval Research Contract N6 ONR-244, Task Order 25, Project Designation NR-081-095 by the California Institute of Technology dated July, 1954. The new model spectrum analyzer herein described has superseded the model discussed in this preceding report.", "date": "1960-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1960.EERL.1960.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1960.EERL.1960.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Caughey_tk_1960.pdf", "url": "https://authors.library.caltech.edu/records/2c43q-6zd81/files/Caughey_tk_1960.pdf" }, "pub_year": "1960", "author_list": "Caughey, Thomas Kirk; Hudson, Donald E.; et el." }, { "id": "https://authors.library.caltech.edu/records/4vv2s-77b07", "eprint_id": 26488, "eprint_status": "archive", "datestamp": "2023-08-19 03:25:42", "lastmod": "2023-10-24 16:21:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } }, { "id": "Iwan-W-D", "name": { "family": "Iwan", "given": "Wilfred D." } } ] }, "title": "The Wilmot survey type strong-motion earthquake recorder (The U.S.C.G.S. Seismoscope) part II", "ispublished": "unpub", "full_text_status": "public", "abstract": "The results of laboratory tests on the adjustment, accuracy, and performance of the seismoscope are given. The effects of stylus pressure, record plate curvature, method of adjustment, and other factors on the damping characteristics of the pendulum were experimentally investigated, and the results are embodied in recommendations for a standard procedure for the field installation and checking of the instrument. The accuracies of such basic instrument parameters as period and tilt sensitivity were established, and the overall level of duplicability of results attained by typical instruments was determined. A comparison of the behavior of similar instruments made by different manufacturers was made. The results of field tests involving the measurement of actual ground motions caused by blasts and earthquakes are given. The location of some 50 of the Wilmot seismoscopes in a network covering the Los Angeles area is given, together with available information as to local geology and soil conditions at the seismoscope sites.", "date": "1960-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1960.EERL.1960.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1960.EERL.1960.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1960.pdf", "url": "https://authors.library.caltech.edu/records/4vv2s-77b07/files/Hudson_1960.pdf" }, "pub_year": "1960", "author_list": "Hudson, Donald E. and Iwan, Wilfred D." }, { "id": "https://authors.library.caltech.edu/records/jjbxm-0p429", "eprint_id": 26487, "eprint_status": "archive", "datestamp": "2023-08-19 03:03:46", "lastmod": "2023-10-24 16:21:05", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "The Wilmot survey type strong-motion earthquake recorder", "ispublished": "unpub", "full_text_status": "public", "abstract": "A simplified instrument for the direct measurement of one point on the response spectrum of the ground motion caused by strong-motion earthquakes is described, and the theory of operation is developed. Determinations of the physical characteristics of two test instruments of a standardized design suitable for large scale production and installation are discussed. Direct comparisons between the instrument results and the spectrum analysis of base accelerations are given, and the conclusion is reached that the device in its present form is suitable for the contemplated application to strong-motion earthquake measurement.", "date": "1958-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1958.EERL.1958.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1958.EERL.1958.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1958.pdf", "url": "https://authors.library.caltech.edu/records/jjbxm-0p429/files/Hudson_1958.pdf" }, "pub_year": "1958", "author_list": "Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/eewgr-ay603", "eprint_id": 26535, "eprint_status": "archive", "datestamp": "2023-08-19 02:20:49", "lastmod": "2023-10-24 16:22:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "Earthquake pressures on fluid containers", "ispublished": "unpub", "full_text_status": "public", "note": "Eighth Technical Report under Office of Naval Research Contract N6 onr-244, Task Order 25, project designation NR-081-095", "abstract": "The dynamic fluid pressures developed during an earthquake are of importance in the design of structures such as dams, tanks and caissons. The first solution of such a problem was that by Westergaard (1933) who determined the pressures on a rectangular, vertical dam when it was subjected to horizontal acceleration. Jacobsen (1949) solved the corresponding problem for a cylindrical tank containing fluid and for a cylindrical pier surrounded by fluid. Werner and Sundquist (1949) extended Jacobsen's work to include a rectangular fluid container, a semicircular trough, a triangular trough and a hemisphere. Graham and Rodriguez (195Z) gave a very complete analysis of the impulsive and convective pressures in a rectangular container. Hoskins and Jacobsen (1934) measured impulsive fluid pressures and Jacobsen and Ayre (1951) gave the results of similar measurements. Zangar (1953) presented the pressures on dam faces as measured on an electrical analog.\nThe foregoing analyses were all carried out in the same fashion, which requires finding a solution of Laplace's equation that satisfies the boundary conditions. With these known solutions as checks on accuracy it is possible to derive solutions by an approximate method which avoids partial differential equations and series and presents solutions, for a number of cases in simple closed form. The approximate method appeals to physical intuition and makes it easy to see how the pressures arise. It thus seems to be particularly suitable for engineering applications.\nTo introduce the method the problem of the rectangular tank is treated in some detail. Applications to other types of containers are treated more concisely. The essence of the method is the estimation of a simple type of flow which is similar to the actual fluid movement and this simple flow is used to determine the pressures. The method is analogous to the Rayleigh-Ritz method used in the theory of elasticity, and it always overestimates the forces. The method is capable of solving a wide variety of problems but if it is required that the solutions be in simple form, which they should to be practically useful, the number of problems that can be handled satisfactorily are limited, just as in the case of the Rayleigh-Ritz method. Acknowledgement is due C. M. Cheng for carrying out the calculations in this report.", "date": "1954-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1954.EERL.1954.003", "official_url": "https://resolver.caltech.edu/CaltechEERL:1954.EERL.1954.003", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "Housner_gw_1954.pdf", "url": "https://authors.library.caltech.edu/records/eewgr-ay603/files/Housner_gw_1954.pdf" }, "pub_year": "1954", "author_list": "Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/jqhv8-1k842", "eprint_id": 26478, "eprint_status": "archive", "datestamp": "2023-08-19 02:20:37", "lastmod": "2023-10-24 16:20:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Caughey-T-K", "name": { "family": "Caughey", "given": "Thomas Kirk" } }, { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } } ] }, "title": "An electric analog type response spectrum analyzer for earthquake excitation studies", "ispublished": "unpub", "full_text_status": "public", "abstract": "The design of a response spectrum analyzer for earthquake excitation studies is described. Electric analog techniques are used, with a series inductance, capacitance, and resistance circuit forming a direct analog to the mechanical structure. The circuit arrangement permits a determination of system response for a sequence of periods at constant damping. Provision is made for obtaining zero damping in the circuit. An arbitrary function generator of the variable width film photoelectric cell type is described. The results obtained with the function generator- spectrum analyzer system for a half-sine wave pulse are compared with the mathematically obtained exact answers for the zero damping case, and the accuracy of the system is shown to be satisfactory.", "date": "1954-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1954.EERL.1954.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1954.EERL.1954.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Caughey_tk_1954.pdf", "url": "https://authors.library.caltech.edu/records/jqhv8-1k842/files/Caughey_tk_1954.pdf" }, "pub_year": "1954", "author_list": "Caughey, Thomas Kirk and Hudson, Donald E." }, { "id": "https://authors.library.caltech.edu/records/pkjrf-f9694", "eprint_id": 26486, "eprint_status": "archive", "datestamp": "2023-08-19 02:20:41", "lastmod": "2023-10-24 16:21:03", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "Vibration tests of a steel-frame building", "ispublished": "unpub", "full_text_status": "public", "abstract": "The natural frequency and damping of a steel-frame building were experimentally determined for the first two modes of vibration from a steady state resonance curve obtained with a variable frequency mechanical oscillator. The value of the first natural frequency was 3.5 cps, which may be compared with the 2.9 cps frequency which was determined from calculations of the response to the transient excitation of a quarry blast. The difference in these frequencies is explained by the fact that somewhat different modes of vibration were excited by the two tests, and by possible differences in structural damping at the high and low amplitude levels of the two tests. The maximum accelerations set up during the steady state tests were of the order of 0.005 g., whereas the accelerations during the blast reached values around 0.1 g. The damping measured for the low amplitude steady state vibrations was 3.416 of critical damping.", "date": "1954-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1954.EERL.1954.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1954.EERL.1954.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Hudson_1954.pdf", "url": "https://authors.library.caltech.edu/records/pkjrf-f9694/files/Hudson_1954.pdf" }, "pub_year": "1954", "author_list": "Hudson, Donald E. and Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/mbpy8-feg42", "eprint_id": 26483, "eprint_status": "archive", "datestamp": "2023-08-19 02:09:13", "lastmod": "2023-10-24 16:20:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "Analysis of the Taft accelerogram of the earthquake of 21 July 1952", "ispublished": "unpub", "full_text_status": "public", "abstract": "In a previous report of work done under contract with the Office of Naval Research there were presented the spectra of all suitable strong-motion earthquake accelerograms recorded prior to August, 1951. On July 21, 1952 a strong earthquake occurred in the region of Arvin and Tehachapi, California.. The ground accelerations were recorded at Taft, California on an instrument maintained by the U. S. Coast and Geodetic Survey. The present report gives the spectra as computed from the Taft accelerograms.", "date": "1953-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1953.EERL.1953.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1953.EERL.1953.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "Housner_sept.1953.pdf", "url": "https://authors.library.caltech.edu/records/mbpy8-feg42/files/Housner_sept.1953.pdf" }, "pub_year": "1953", "author_list": "Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/3dxhk-1ee02", "eprint_id": 26482, "eprint_status": "archive", "datestamp": "2023-08-19 02:09:09", "lastmod": "2023-10-24 16:20:55", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "A Dislocation theory of earthquakes", "ispublished": "unpub", "full_text_status": "public", "abstract": "A mechanism for the generation of seismic waves is postulated that is based on the release of shear strain dislocations. A certain probability of release of dislocations is also postulated. From these there are deduced expressions for the frequency distribution of shocks, energy released, etc., that are in agreement with observations. It is shown that a random superposition of pulses such as those released by individual dislocations will form an accelerogram, that has the appearance and properties of recorded accelerograms. The relation between the maximum ground acceleration and the size of slip area is examined. It is concluded that the existing recorded strong ground motion accelerograms are reliable samples of possible strong ground motions.", "date": "1953-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1953.EERL.1953.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1953.EERL.1953.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Housner_gw_1953.pdf", "url": "https://authors.library.caltech.edu/records/3dxhk-1ee02/files/Housner_gw_1953.pdf" }, "pub_year": "1953", "author_list": "Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/s16tc-ah892", "eprint_id": 26481, "eprint_status": "archive", "datestamp": "2023-08-19 01:57:44", "lastmod": "2023-10-24 16:20:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "Intensity of ground motion during strong earthquakes", "ispublished": "unpub", "full_text_status": "public", "abstract": "A measure of the surface intensity of the ground motion during an earthquake is defined which is proportional to the maximum stresses produced in structures. Intensities are computed for fourteen strong-motion shocks and these are compared with the Modified-Mercalli Intensities for the same earthquakes. A method is developed for computing the magnitude of an earthquake from the intensity and vice versa which permits the intensities to be calculated over the area affected by the earthquake. The maximum intensity and the maximum ground acceleration likely to be experienced by a California city are estimated. The frequency with which strong earthquakes are likely to occur in California is determined and an estimate is made of the frequency with which a California city is likely to experience severe ground. motion.", "date": "1952-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1952.EERL.1952.001", "official_url": "https://resolver.caltech.edu/CaltechEERL:1952.EERL.1952.001", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory" } ] }, "primary_object": { "basename": "Housner_gw_1952.pdf", "url": "https://authors.library.caltech.edu/records/s16tc-ah892/files/Housner_gw_1952.pdf" }, "pub_year": "1952", "author_list": "Housner, George W." }, { "id": "https://authors.library.caltech.edu/records/jnnv6-67r62", "eprint_id": 26485, "eprint_status": "archive", "datestamp": "2023-08-19 01:57:48", "lastmod": "2023-10-24 16:21:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hudson-D-E", "name": { "family": "Hudson", "given": "Donald E." } }, { "id": "Alford-J-L", "name": { "family": "Alford", "given": "Jack L." } }, { "id": "Housner-G-W", "name": { "family": "Housner", "given": "George W." } } ] }, "title": "Response of a structure to an explosive-generated ground shock", "ispublished": "unpub", "full_text_status": "public", "abstract": "Measurements were made of ground accelerations and the resulting building accelerations at a point very near a large quarry blast. It is shown that, in the case of simple buildings, the building acceleration may be calculated with satisfactory accuracy from a knowledge of the ground acceleration.\n\nThe response of the test building to the ground acceleration of a typical strong-motion earthquake was computed, and it was found that the resulting accelerations were in excess of those usually provided for in earthquake-resistant design. It is concluded that the satisfactory performance of well-designed structures during strong earthquakes may have two explanations: first, that vibration energy is dissipated by stresses in excess of the elastic limit, with the result that hidden damage may occur; and second, that ordinary buildings may have sources of strength which are not taken into account in their design.", "date": "1952-01-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechEERL:1952.EERL.1952.002", "official_url": "https://resolver.caltech.edu/CaltechEERL:1952.EERL.1952.002", "rights": "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format.", "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Earthquake-Engineering-Research-Laboratory", "value": "Earthquake Engineering Research Laboratory" } ] }, "primary_object": { "basename": "Hudson_1952.pdf", "url": "https://authors.library.caltech.edu/records/jnnv6-67r62/files/Hudson_1952.pdf" }, "pub_year": "1952", "author_list": "Hudson, Donald E.; Alford, Jack L.; et el." } ]