Abstract
The dynamic behavior of a structure during intensive earthquakes is considerably affected by the properties of soil beneath the structure. Then, in the earthquake response analysis of a structure, it is necessary to take account of the interaction effect of soil ground. In this paper, the mathematical model of a ground-structure system is assumed to consist of above-ground, main structure, boundary soil layer and elastic ground. The main structure and the boundary layer have restoring characteristics of a bilinear hysteretic type. Applying a statistically equivalent linearization technique to the nonlinear restoring function, elasto-plastic response characteristics of an interaction system to a white random excitation are presented. It is pointed out that the nonlinear characteristics of soil ground affect largely upon the dynamic response of a main structure and that the interaction effect upon the elasto-plastic response of a structure differs from that on an elastic one.
