AN ANALYSIS OF LARGE-STRAIN DAMAGE ELASTOPLASTICITY

The elastoplastic constitutive analysis which utilizes the model of mu ltiplicative decomposition of the deformation gradient into its elasti c and plastic parts has been mainly developed and applied to elastical ly isotropic materials, which remain isotropic during the process of p lastic deformation. This paper extends the application of the model to materials that change their elastic properties during the deformation process as a result of the material degradation and the corresponding damage. The exact kinematic and kinetic analysis of the finite deform ations leads to an additive decomposition of the total strain rate int o its elastic, damage and plastic constituents. The general structure of the expression for the damage strain rate is derived, valid for uti lized damage tensors of any order. The analysis of elastoplastic defor mation of elastically anisotropic materials without damage is also pre sented, with the application to transversely isotropic materials. The relationships between the elastic and plastic strain rates and the com ponents of the multiplicative decomposition and their rates are also g iven.