Modélisation des anisotropies mécaniques induites par la fissuration du béton

Abstract

ABSTRACT Concrete cracking is modeled in the general framework of anisotropic damage theory with anelastics strains. The use of anisotropic criteria allows to describe both direct and induced tension cracks that appear at the aggregate—cement paste interfaces; thus damage is represented by two second order tensors for direct and induced tension, respectively, which define the marginal damages. A possible rotation of the cracks is obtained by formulating the criteria flow in the principal axes of effective stresses. Mechanical damage approximation is deduced from marginal damages by using the weakest link theory extended to the cases of non proportional loading. This method, which makes it possible to couple several non coaxial damage tensors, is presented in this paper in a restrained framework including only mechanical cracking causes; nevertheless it can be generalized without difficulties to other cracking causes (chemical damage for example). In finite element context, objectivity of the post peak ten...