A numerical method to evaluate the material properties degradation in composite RVEs due to fiber-matrix debonding and induced matrix cracking

One of the most important issues about the behaviour of composite materials subjected different loading conditions is the initiation and propagation of various damage modes, which have significant effects on their application. In the present study, the cohesive zone model (CZM), as well as extended finite element method (XFEM) are used in the form of a new numerical method to study the effects of initiation and propagation of damage modes including fiber-matrix debonding and matrix cracking in different RVEs extracted from composite plies. To this end, some appropriate assumptions and boundary conditions are used to evaluate the reduced mechanical properties of RVEs. Firstly, CZM is used to model and study the fiber matrix debonding damage. Then by simulating the matrix cracking formation using XFEM, effects of fiber-matrix debonding as well as matrix cracking on the stiffness of composite are studied simultaneously. The precision of the numerical simulation on modelling of the mentioned damage modes is validated by the available numerical researches. The obtained results can be applied to provide the macroscopic constitutive behaviour according to computational homogenization techniques, which is undertaken by the authors.