Wave computations in irregular layered media using a semidiscrete finite element perturbation method

Abstract

SUMMARYA technique that takes into account nonparallel interfaces and lateral inhomogeneities as perturbations with respect to a reference, horizontally layered, laterally homogeneous medium and produces approximations of the perturbed wave motion with little additional computation effort is described. The formulation combines a perturbation method with a semidiscrete finite element technique, providing an approximate treatment of wave propagation in irregular layered media. Consistent transmitting boundaries and other semidiscrete hyperelements as well as Green's functions, already available for regular layered media, can be reformulated within the framework of the method. The method is relevant in problems of foundation dynamics, ground response to seismic waves and site characterization. Example problems are presented toward evaluation of the effectiveness of the method.

Modelling ground vibrations induced by harmonic loads

“…The TLM was first developed by Waas (1972) and has been extended and used by various other authors such as Kausel (1974), Tassoulas (1981), Laghrouche (1996), Park and Tassoulas (2002), Ikeda and Tassoulas (2008), Hamdan et al (2013) and others. It can be used to compute the nodal forces needed on the lateral domain boundaries to allow wave radiation to infinity.…”