Numerical simulation of quasi-brittle fracture using damaging cohesive surfaces

The cohesive surface methodology is used in a numerical study of fracture o f concrete. The traction vs. separation response is governed by an isotropi c damage law in which damage evolves according to a prescribed one-dimensio nal linear or exponential softening law. Cohesive surfaces are immersed in the continuum to allow for a maximum freedom of crack path selection. The s ingle edge notched four point shear beam and the double edge notched tensil e bar are used to study: (i) the influence of the tangential cohesive respo nse on the development of the fracture path and (ii) the mesh alignment sen sitivity. It is shown that in the present formulation, the tangential cohes ive response has a minor influence on both crack path and global characteri stics. Mesh alignment does have a significant influence on the outcome of t he numerical analysis. (C) 2000 Editions scientifiques et medicales Elsevie r SAS.