On the Earthquake Response of Structural Systems Considering the Interaction Effects of the Ground

Abstract

In earthquake engineering, it is important to estimate reasonably the effects of the ground characteristics on the earthquake responses of above-ground structures. In this paper, the ground characteristics in an elastic range are represented as the dynamic ground compliance of a foundation on an elastic half-space that means a force-displacement transfer function of an elastic ground-foundation system. Supposing bilinear hysteretic restoring force characteristics in an above-ground structure and an elasto-plastic boundary layer underneath the foundation, the nonlinear transient responses of a ground-structure system subjected to horizontal ground acceleration excitations are analyzed in a wide parameter range. The random time functions obtained through a noise generator are used for this response analysis as ground acceleration excitations. As a result of the present study, it is pointed out that an interaction effect of the ground may act advantageously on a structural earthquake response in usual cases, while a disadvantageous effect should be considered when large plastic behaviours of structures are anticipated during earthquakes.