A multi-domain IBEM for the wave scattering and diffraction of P- and SV-waves by complex local sites

This is the authors' abstract. We don't add key points for this paper.

By virtue of the specific advantages of full-space indirect boundary element method (IBEM) and the half-space one, a multi-domain IBEM is proposed to address the in-plane wave scattering problem of complex local sites. First, the whole model is decomposed into closed individual regions and opened half-space region. Then, the full-space and half-space IBEM are employed to simulate the scattered fields in closed and opened regions, respectively. And the direct stiffness method is used to compute the free fields of the layered half-space. Finally, all the regions are assembled to the original one incorporating the traction-free or compatibility conditions. The accuracy is validated by comparing with the existing results. And the multi-domain IBEM is further utilized to solve four different complex models i.e. a valley-hill coupled topography, a triple-layered valley, a triple-layered inclusion and triple circular inclusions. It is shown that the multi-domain IBEM can dramatically reduce the number of elements compared with the full-space IBEM while extremely save calculation time compared with the half-space IBEM. In addition, results indicate that the wave fields in and around the coupled models are much more complex than the simple single one, which may lead to larger amplifications of surface motion.