The Earthquake Engineering Online Archive

Deconvolution of seismic response for linear systems

Reimer, Richard B.

UCB/EERC-73/10, Earthquake Engineering Research Center, University of California, Berkeley, 1973-10, 162 pages (525/R364/1973)

Methods of computing the response of linear structural systems to a general dynamic excitation have been well known for many years. In the case of buildings the response to a time-varying support displacement caused by a seismic event or, less commonly, the response to wind gusts or vibrating machinery within the structure may be desired. The use of high-speed, large-capacity digital computers together with improved discretized models of the structural system such as finite element models have reduced such analyses to routine procedures. This report is concerned with the study of techniques for determining the seismic excitation of a discretized, linear structural model that would produce a response similar to that measured by an accelerograph at some point on the modeled physical system. The subject of deconvolution is first introduced and several analytical techniques for performing an analysis for civil engineering structures are reviewed. A frequency domain technique which avoids the difficulties associated with time domain analyses is then introduced and a computational algorithm presented. The algorithm is then applied to a three-dimensional finite element structural system which forms a mathematical model of Pacoima Dam and its surrounding geological structure. The effects of the dam and structure on the nature of the accelerogram recorded near the left abutment of the dam in the San Fernando earthquake are then determined in terms of the seismic excitation of the mathematical model that would be required to reproduce the actual accelerogram. Finally the application of the proposed algorithm to other structural models is discussed and recommendations made for further research.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-73-10.pdf (4 MB)