A meshfree penalty-based approach to delamination in composites

Cohesive models have been successfully employed to simulate delamination in composites, since they can provide accurate description of both onset and propagation. The key parameter of a cohesive model is interpreted in this work as a penalty parameter to fully exploit the many advantages of meshfree techniques. This penalty factor is then modified according to the cohesion strength between the parts, depending on a softening law to track the damage state of the layers interface and to prevent the restoration of the undamaged cohesive state during unloading. The approach is used for simulating the steady-state evolution of delamination in composite structures for quasi-static loading modes I and II. To demonstrate the validity of the proposed methodology, the results were compared with experimental data showing promising accuracy and robustness.