Dynamic soil-structure interaction of monopod and polypod foundations

The paper concerns the importance of through–soil coupling for structures having foundations with more footings. First, a model for dynamic analysis of polypod footings is established in the frequency domain, employing Green’s function for wave propagation in a layered half-space. To allow analysis within the time domain, frequency-independent lumped-parameter models are developed. The paper proposes a decision criterion for determination of which components must be included within a lumped-parameter model in order to account for the structure–soil–structure interaction in an adequate and efficient manner. As a computational example, the dynamic response of a plane frame structure with two footings is compared for two cases: one with and one without the cross coupling. Homogeneous as well as layered soil is considered.