A micromechanics-based thermodynamic formulation of isotropic damage with unilateral and friction effects

Abstract

Abstract This paper is devoted to micromechanical modeling of isotropic damage in brittle materials . The damaged materials will be considered as heterogeneous media composed of solid matrix weakened by isotropically distributed microcracks . The original contribution of the present work is to provide a proper micromechanical thermodynamic formulation for damage-friction modeling in brittle materials with the help of Eshelby’s solution to matrix-inclusion problems. The elastic and plastic strain energy involving unilateral effects will be fully determined. The condition of microcrack opening–closure transition will be determined in both strain-based and stress-based forms. The effect of spatial distribution of microcracks will also be taken into account. Further, the damage evolution law is formulated in a sound thermodynamic framework and inherently coupled with frictional sliding . As a first phase of validation, the proposed micromechanical model is finally applied to reproduce basic mechanical responses of ordinary concrete in compression tests.