Role of Soil-Structure Interaction in Base-Isolated Structures Founded on Soil Stratum Overlying Half Space

This paper attempts to assess the role of soil-structure interaction (SSI) and higher modes in base-isolated structures founded on a soil layer overlying a half space. Closed form solutions for a system that includes a superstructure, seismic isolator and soil stratum overlying a half space have been obtained. The derived formulations considering the effects of SSI and higher modes in terms of well-known frequency and impedance ratios can explicitly interpret the dynamic behavior of a base isolated structure founded on soil stratum overlying a half space. Furthermore, the SSI effects on dynamic responses of isolated structures founded on soil stratum overlying a half space were extensively investigated. The conclusions drawn by this study provide considerable information for comprehending the SSI and higher mode effects on the dynamic responses of isolated-structures especially for those founded on soil stratum overlying a half space.