A 3D time domain SSI method based on half-space Green's functions considering internal soil attenuation

This paper describes a numerical method based on a three dimensional boundary element-finite element (BEM-FEM) coupled formulation in time domain. Proposed model allows to study soil-structure interaction problems. The soil is modelled with the BEM, and the radiation condition is implicitly satisfied in the fundamental solution. The FEM is used to represent the structure. This work uses the half-space Green's functions, and the internal soil damping is considering directly in the time domain. The half-space fundamental solution has singularities at the arrival time of Rayleigh waves. Effective treatment based on the integration into a complex Jordan path is proposed to avoid these singularities. BEM efficiency is improved taking into account the spatial symmetry and the invariance of the fundamental solution when it is expressed in dimensionless form. Proposed method is verified by comparison with analytical solutions.