In order to investigate near-field ground motions, an important Lucerne Valley record from the Landers earthquake is 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 is conducted and a new data processing procedure is developed to perform the instrument and baseline corrections.
\r\n\r\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\r\ninstrument correction and a laboratory test of the SMA-2/EMA accelerograph was conducted for obtaining the characteristic parameters of the instrument. The possible\r\nerror 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.
\r\n\r\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.
" }, { "name": "Irvine, Hilary Max", "degree": "Engineering Degree", "year": "1974", "title": "Studies in the Statics and Dynamics of Simple Cable Systems", "advisor": "Jennings, Paul C.; Caughey, Thomas Kirk", "url": "https://resolver.caltech.edu/CaltechThesis:10162019-164456880", "creators": [ { "name": { "family": "Irvine", "given": "Hilary Max" }, "id": "Irvine-Hilary-Max", "display_name": "Irvine, Hilary Max" } ], "advisors": [ { "name": { "family": "Jennings", "given": "Paul C." }, "id": "Jennings-P-C", "role": "advisor", "display_name": "Jennings, Paul C." }, { "name": { "family": "Caughey", "given": "Thomas Kirk" }, "id": "Caughey-T-K", "role": "advisor", "display_name": "Caughey, Thomas Kirk" } ], "committee": [ { "name": { "family": "Unknown", "given": "Unknown" }, "display_name": "Unknown, Unknown" } ], "option_major": [ "civileng" ], "doi": "10.7907/K4Y4-8H02", "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.
\r\n\r\nClosed form solutions are given to a variety of cable problems which have important applications in practice. The work is divided into two chapters.
\r\n\r\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.
\r\n\r\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.
\r\n\r\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.
" } ]