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Title
Ambient and Forced Vibration Studies of a Multistory Triangular-Shaped Building. Proceedings of the American Society of Civil Engineers, Engineering Mechanics Division Specialty Conference Held at University of California at Los Angeles on March 30-31, 1976.
File
PB80196744.pdf
Author(s)
Stephen, R. M.; Petrovski, J.
Source
National Science Foundation, Washington, DC. Engineering and Applied Science., March 1976, 13 p.
Abstract
The computer model formulations of structures have made available for study the elastic, and in certain structural systems, the inelastic response of structures when subjected to earthquakes. Dynamic field test data covering the complete dynamic characteristics of full-scale structures and providing natural frequencies, mode shapes, and damping values have been considered essential in the development of computer-model formulation techniques. To assess the feasibility of general purpose computer programs in predicting accurately the response of buildings with complex configurations and to accumulate a body of information on the dynamic properties of structures, a number of dynamic tests have been conducted on full-scale structures. The dynamic tests, using forced and ambient methods, which were performed during November, 1974 and March, 1975 on the Century City South-Theme Tower in Los Angeles, California, are reported in this paper. Because of the favorable advantages of the ambient vibration method in dynamic testing of full-scale structures, it was desirable to compare both methods in order to assess the accuracy of each method in evaluating the dynamic properties of the structural systems. Comparison of the forced and ambient vibration experiments demonstrate that it is possible to determine with adequate accuracy the natural frequencies and mode shapes of typical modern buildings using the ambient vibration method.
Keywords
Earthquake resistant structures; Dynamic tests; Dynamic response; Forced vibration; Earthquake engineering; Resonant frequency; Earthquakes; Dynamic structural analysis