Mechanism analysis of earthquake responses of rigid pile composite foundation

Concerning the aseismic ability of rigid pile composite foundation, the equivalent linear method and its parameter values are verified by shaking table tests of rigid pile composite foundation; some practical cases are analyzed by means of 3D finite element method. The effects of layered foundation, soil modulus, pile diameter and pile length, cushion thickness and cushion modulus etc. on the earthquake responses of rigid pile composite foundation are discussed; and the aseismic mechanism of rigid pile composite foundation is studied. It is found that the equivalent linear method can adequately simulate the characteristics of the interaction between structure and composite foundation; the inertia force of the superstructure and the deformation of the free field have notable impact on the inner forces in piles; the inner forces in piles tend to remarkably increase for the existence of weak layers in soil.