Modelling of delamination growth in composite laminates by the virtual internal bond method

The paper examines the potential of the virtual internal bond (VIB) model to predict delamination initiation and growth in composite laminates. Finite elements implementing a formulation of the VIB model based on a two-parameter bond potential were used to simulate the resin-rich interface between adjacent layers. The performance of VIB elements was assessed by modelling the fracture response of unidirectional laminates with different cohesive strengths and fracture energy values in DCB, ENF and MMB tests. Even though some issues that restrict the applicability range of the model remain to be addressed, the good agreement achieved between finite element results and both analytical solutions and experimental results demonstrates the capability of VIB-based finite element models to correctly simulate the mechanics of delamination under different loading modes.