Efficient modal analysis for structures with soil‐structure interaction

Abstract

Abstract An efficient methodology is presented which uses modal analysis implemented in the frequency domain to obtain the structural response of a system with soil‐structure interaction. The interaction effects are represented using a free‐field ground motion modification factor, derived for each mode of vibration and used in the determination of structural response. Applying this algorithm, the advantages of the modal superposition method are fully exploited, and the interaction problem can be solved easily and effectively within the framework of the conventional frequency domain analysis for a fixed‐base structure. In addition, this method produces accurate approximation with less computational effort due to consideration of only the first few vibration modes of the structure.