An enriched cohesive law using plane-part of interfacial strains to model intra/inter laminar coupling in laminated composites

Proper modeling of the interplay between transverse cracks and delamination is crucial in accurately simulating degradation in laminated composites. However, up to now, there is no computationally friendly model to account for this intra/inter laminar coupling. In this paper, a new hybrid cohesive law has been proposed in which the damage could be activated by both out-of-plane separation and in-plane strains of the interlaminar interface. By doing so, the in-plane strain can be used to estimate the damage state of the adjacent plies to the interface, so the response of the cohesive element is modified accordingly. This provides an efficient framework to account for the effect of intralaminar transverse cracks onto the delamination resistance. Through the authors’ earlier work, the influence of intralaminar damage on interlaminar properties is twofold: harmful (through transverse crack-induced delamination) or beneficial (transverse crack-induced bridging). Both coupling effects are embedded in the hybrid cohesive elements. The modeling parameters are calibrated using rigorous experimental data. The simulation results demonstrate the potential of the pragmatic cohesive element proposed in this paper.