Dynamic interaction analysis of structure-water-soil-rock systems under obliquely incident seismic waves for layered soils

Abstract

A numerical model for the structure-water-soil (layered)-rock (SWLR) system is proposed in this paper to evaluate the system dynamic response, in which the fluid-solid coupling effect is considered by the interface conditions and the wave radiation effects of far-field domain are simulated by artificial boundary conditions. Moreover, this model covers four prime respects, including the discretization of interface conditions, the absorbing boundary conditions, the equivalent earthquake loading input and the general finite element equation. It can be solved by a standard time integration algorithm such as implicit Newmark's method. Furtherly, the effectiveness of the proposed model is verified by three numerical examples. Apart from these, the dynamic stiffness matrix method (DSM) of fluid and solid adopted in present study to acquire the equivalent earthquake loading effectively accomplishes the oblique incidence of the wave in layered half-space with arbitrary angles. Based on the proposed model, the effects of dynamic water-structure interaction (WSI) and soil-water interaction (SWI) on the seismic responses of offshore structure are investigated, which is conducive to the simplified analysis of dynamic fluid-solid interaction and the design of ocean engineering.