An anisotropic elastoplastic-damage model for plain concrete

A material model for plain concrete formulated within the framework of multisurface elastoplasticity-damage theory is proposed in this paper. Anisotropic stiffness degradation as well as inelastic deformations are taken into account. The applicability of the model encompasses cracking as well as the non-linear response of concrete in compression. The effect of different softening laws on the stress–strain relationship and on the dissipation is investigated in the context of a 1D model problem. The integration of the evolution laws is based on the standard return map scheme. Further computational issues include the stability of the local iteration procedure and the treatment of the apex region of the damage surface. The model is employed for re-analyses of a cylinder splitting test and of a notched concrete beam. Results from the composite elastoplastic-damage model are compared with test results and results from other material models for concrete, respectively. © 1998 John Wiley & Sons, Ltd.