Modeling interfacial debonding and matrix cracking in fiber reinforced composites by the extended Voronoi cell FEM

This paper introduces an extended Voronoi cell finite element model (X-VCFEM) for modeling the initiation and propagation of interfacial debonding and matrix cracking in fiber reinforced composite materials. Bilinear and linear cohesive zone models are added for representing interfacial debonding and matrix crack propagation, respectively. A series of criteria based on cohesive zone models are proposed for assessing the direction of damage development, which includes the crack propagation in matrix and its deflection behavior at an interface. Comparisons of X-VCFEM simulations with reference results validate the effectiveness of this new model. The capability of predicting the development of microcracks in composites is of great importance to the design and evaluation of structure. Effect of stereographic features such as size and shape of heterogeneities on damage evolution is also discussed.