Analysis of the elastic-plastic problem involving finite plastic strain using the boundary element method

This paper presents a formulation of the static problem of metallic solids undergoing both material and geometrical non-linearities. The plastic const itutive relations are based on the von Mises yield criterion with associate d flow rule and isotropic hardening. The plastic strains can be large. The numerical approach is based on the boundary element method (BEM) but, since it is not possible to take all the integrals to the boundary, both domain and boundary discretization are needed. A material description is adopted t ogether with an updated Lagrangian approach. The generalized midpoint algor ithm is used for the,computation of the large scale plastic strains, The di splacement gradients are obtained, in order to avoid singularities, from po lynomial differentiation of the displacement field in each domain element f rom the nodal values. The resulting method is incremental and iterations ar e needed in each increment. The two-dimensional plane strain case has been implemented and one example is presented, to show the applicability of the method proposed. (C) 1999 Civil-Comp Ltd and Elsevier Science Ltd. All righ ts reserved.