Direct 3D BEM for scattering of elastic waves in a homogeneous anisotropic half-space

Abstract

A direct 3D time-harmonic boundary element method is applied to determine the elastic response of a cavity of arbitrary shape embedded within a 3D homogeneous triclinic half-space. The boundary integral equations for scattered wave field are used in the boundary element method (BEM). Because of the full-space fundamental solutions in the formulation, the traction-free conditions on the half-space surface must be imposed separately. Numerical testing is performed for a 3D isotropic case in order to obtain the size of the half-space discretization surface that ensures the accuracy of the results. Applications are discussed for scattering of elastic waves by a semispherical canyon. The results show that the anisotropic response strongly depends on the incident wave, the material anisotropy and the location of the observation points.