Numerical insight of a variational smeared approach to cohesive fracture

In the present paper we numerically investigate and validate a variational smeared model for cohesive crack, recently proposed and theoretically justified by Gamma-convergence. To achieve this main goal, we first analyze the response of a bar subjected to traction. Possible solutions are discussed, reconstructing the classical cohesive fracture energy and its related stress-crack opening law through a backtracking procedure. Preliminary 2D investigations are also conducted by using a regularized version of the adopted formulation. This permits to explore the transition phase of the damage evolution and to determine the peculiarities of the model, such as mesh-objectivity and Gamma-convergence as damage concentration is forced. Therefore, the numerical simulations confirm the analytical results and put the basis for further engineering applications and possible improvements of the model. (C) 2016 Elsevier Ltd. All rights reserved.