Interaction effects of adjacent structure resulting from coupling of the foundations through the soil are frequently ignored in the seismic analysis of nuclear power plants and each raft is treated as isolated from any such effects.
In this paper such compling effect is investigated for a number of different model by parametric study. The model used in this study is a lumped parameter model derived from elastic half-space considerations. The soil-structure system idealized using beam elements with lumped soil springs and dampers beneath each foundation plus a coupling matrix between the interacting foundations.
The influence of mass and natural frequency of structure, soil property, distance between the two structures, is studied by comparing the dynamic response of each model.