Some Remarks on the Damage Unilateral Effect Modelling for Microcracked Materials

Abstract

This study deals with the macroscopic modelling of the mechanical behaviour of microcracked materials and particularly with the unilateral aspect of such damage which leads, at the closure of microcracks, to a partial damage deactivation. By means of a micromechanical analysis, the aim of this article is first to point out the influence of the opening–closure of microdefects on the effective elastic properties of a microcracked medium. According to these considerations,a new elastic moduli recovery condition at damage deactivation is proposed. The introduction of this condition within the anisotropic damage model proposed by Halm and Dragon, 1996 allows its micromechanical background to be extended while preserving its main advantages, in particular the continuity of the stress–strain response and the symmetry of the stiffness tensor.