High-performance parallel simulation of structure degradation using non-local damage models
Résumé
Simulating damage and failure of metallic or composite structures often fails when using standard finite element discretizations and a Newton-Raphson solving procedure. The difficulties arise from an uncontrolled mesh dependency caused by damage localization, to structural instabilities and to an increase of computational costs. The first problem can be overcome by using non-local damage constitutive equations together with a specific finite element model. The second problem can then be solved with an arc-length method which manages instabilities and snap-backs. They are caused by the loss of strength-carrying capacity of the damaged material. Finally, the whole computational scheme is parallelized. The main contribution of this paper consists in bringing together the three numerical techniques: non-local material model; piloting and parallel computations. The resulting numerical scheme allows to go beyond the overly simplistic cases often encountered in the literature. It allows robust industrial simulations with a high number of degrees of freedom, both in two and three dimensions, and deepened studies involving a large number of simulations.