A posteriori error estimation and mesh adaptation for finite element models in elasto-plasticity

A new approach to a posteriori error estimation and adaptive mesh design ba sed on techniques from optimal control is presented for primal-mixed finite element models in elasto-plasticity. This method uses global duality argum ents for deriving weighted a posteriori error bounds for arbitrary function als of the error representing physical quantities of interest. In these est imates local residuals of the computed solution are multiplied by certain w eights which are obtained by solving a linearized global dual problem numer ically. The resulting local error indicators are used in a feed-back proces s for generating economical meshes. This approach is developed here for the Hencky and Prandtl-Reuss models in linear-elastic perfect plasticity. Its performance is demonstrated for a plane-strain benchmark problem. (C) 1999 Elsevier Science S.A. All rights reserved.