A boundary element method for three-dimensional elastoplastic problems

An efficient boundary element method (BEM) formulation for three-dimensional elastoplasticity is presented in this paper. The BEM formulation for nonlinear problems requires discretization of the surface as well as part of the volume. In this paper nine-noded quadrilateral elements are used for modelling the surface and 27-noded brick elements for the volume. Particular attention is paid to the accurate evaluation of the Cauchy principal value volume integrals appearing in the interior stress calculations. An explicit initial strain formulation is used to satisfy the nonlinearity. The accuracy of the proposed method is demonstrated by solving a number of benchmark problems.