Modeling damage in finite elasto-plasticity

Abstract

In this paper we describe models of damaged materials within the constitutive framework of finite, multiplicative elasto-plasticity. The anisotropic damage is characterized by a second order invertible tensor, Fd− the damage deformation tensor, whose existence is related to an undamaged (fictitious) stress free configuration. The existence of the damage deformation tensor leads to a modified multiplicative decomposition of the deformation gradient F = FeFdFp, where the plastic part of deformation Fp can only affect the undamaged material structure. The behavior of the material is elastic and dependent on the damage deformation tensor Fd, and we adopt the concepts of damage surface and yield surface to describe the irreversible behaviour by the appropriate evolution equations.