An efficient analysis of structural response for multiple-support seismic excitations

A response spectrum method is proposed for the seismic analysis of a multisupport structure subjected to spatially varying ground motion. Based on theoretical results by Der Kiureghian and Hofer, an approximate and efficient analysis of the frequency integral of the cross-correlation function of multisupport excitation is presented. A two-span beam-like structure is studied to demonstrate the application of this proposed method and to characterize the influence of the differential support motion. Treatment of the various combinations of phase relationships between supports is also discussed.