Reciprocal absorbing boundary condition with perfectly matched discrete layers for the time-domain propagation of SH waves in a layered half-space

In this paper, a reciprocal absorbing boundary condition (RABC) is combined with perfectly matched discrete layers (PMDLs) for the time-domain numerical analysis of SH-wave propagation in a layered half-space. The RABC is employed for representation of the layered stratum beyond the vertical consistent transmitting boundary while the PMDLs are applied in order to absorb waves into the underlying homogeneous half-space. The combination of RABC and PMDLs circumvents concerns with the treatment of layered media. The RABC handles layers without any approximation, other than discretization, while PMDLs are used exclusively for the simulation of the homogeneous medium underlying the layers. This combination leads to solution of the problem of anti-plane shear wave-propagation in a layered half space directly in the time domain. Examples are presented demonstrating the accuracy and effectiveness of the proposed combination.