Boundary Element Method for Horizontally Polarized Shear Wave Scattering by an Elliptical Cavity in Orthotropic Graded Saturated Porous Media

The shear wave scattering due to an elliptical cavity in an infinitely long strip of orthotropic graded saturated porous (OGSP) media is studied with the boundary element method (BEM). The shear modulus and the mass density of the OGSP are assumed to have exponential forms. Using Biot's theory, the governing equations are developed for OGSP. The fundamental function is obtained by separating variables in terms of the Dirac delta function. A system of linear equations describing the displacement on the ellipse is obtained by applying the linear BEM. The numerical results for the normalized boundary surface displacements in the scattering field are presented with different OGSP coefficients. The effects of many parameters are evaluated with numerical examples. These results are expected to have great technical interest for determining boundary stability when elastic waves interact with OGSP cavities.