An anisotropic material model for cracked concrete based on plasticity- and damage theory

Tensile loading of plain concrete induces a growth and coalescence of microcracks which results in the formation of macroscopic cracks and progressive degradation of the elastic moduli. This deterioration process prevents a complete closure of microcracks in unloading processes. As a consequence, permanent strains develop. The proposed material model for plain concrete [1] is based on an anisotropic damage evolution law [2] and formulated within the framework of multisurface damage-elastoplasticity allowing for stiffness degradation as well as for the modelling of inelastic deformations. Cracking under tension as well as the nonlinear response of concrete in compression is taken into account.