The Earthquake Engineering Online Archive

Effects of spatial variation of ground motions on large multiply-supported structures

Hao, Hong

UCB/EERC-89/06, Earthquake Engineering Research Center, University of California, Berkeley, 1989-07, 160 pages (450/H27/1989)

The spatial variability of ground motions recorded during 17 earthquakes by a strong-motion accelerograph array in Taiwan (SMART-1) is analyzed. The power spectral density and envelope functions of the ground motion are calculated and compared with previous results. The apparent velocities of the seismic waves are studied in different time windows as a function of frequency. A method is developed to simulate and interpolate multiple ground motions that are spatially correlated, quasi-stationary, and response-spectrum compatible. The equations that describe structural response under multiple ground motion excitations are formulated in the cases both with and without soil-structure interaction effects. Numerical methods for solving these equations in the frequency domain are presented. A computer program SSIAM is developed which uses simulated ground motions as multiple inputs to solve the structural responses. Some examples of ground motion simulation and interpolations are then calculated. The results are presented and compared with the prescribed ground motion properties. Examples of structural responses under simulated multiple ground motion excitations are calculated with soil-structure interaction effects.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-89-06.pdf (6 MB)