A nonlinear friction-cohesive model for characterizing mode II fracture of laminated composites

In this paper, the Coulomb friction is incorporated into the exponential cohesive law, so a nonlinear friction-cohesive model combining sliding friction and interfacial debonding is developed to characterize the mechanical responses of mode II fracture. This model can well simulate the load-displacement curve of ENF test, after properly calibrating the parameters through the experimental data available in the literature. Then, a parametric study to investigate the effects of interfacial parameters on the load-displacement curves of ENF test has been carried out. The results show that, compared with the bi-linear cohesive model and exponential cohesive model, the proposed model is closer to the experimental data. Friction parameters will affect the initial delamination stage and stable delamination stage of ENF test, and interfacial characteristic lengths and interfacial shear strength will affect the peak load of ENF test.