Dynamic debonding phenomena in Z-pin reinforced composite laminates

A computational formulation based on moving mesh technique and multilayer formulation is developed with the purpose to predict crack onset and evolution of layered structures, strengthened with z-pins. In order to identify the positions of the onset interfacial defects and their dynamic debonding mechanisms, a moving mesh strategy, based on Arbitrary Lagrangian-Eulerian (ALE) approach, is combined with the cohesive interface methodology, in which weak based moving connections are implemented by using the finite element formulation. Despite exiting numerical methodologies based on pure CZM, the present approach reduces nonlinearities involved in the constitutive equations to a small region containing the process zone, leading to a quite stable and efficient procedure to identify the actual solution in terms of both crack initiation and evolution. The analysis is proposed also in dynamic framework, in which the influence of time dependence and the inertial forces are taken into account. In order to verify the accuracy and to validate the proposed methodology, comparisons with existing numerical results are proposed.