An extended cohesive damage model for simulating multicrack propagation in fibre composites

Abstract

This paper introduced an extended cohesive damage model (ECDM) for simulating multicrack propagation in fibre composites. The proposed ECDM is developed by introducing a cohesive damage model (CDM) into the eXtended Finite Element Method (XFEM) and eliminating the enriched degree of freedoms (DoFs) to effectively predict multicrack propagation in fibre composites without knowing beforehand the crack paths. A shifted Heaviside function is introduced to approximate existing cracks and crack propagations. A new strain field related cohesive damage law is introduced to describe the behaviour at the crack tip. The proposed ECDM is verified by three fracture test benchmarks and an example of predicting delamination migration together with matrix cracking. This investigation proved that the developed ECDM works very well when compared to analytical and experimental work. This developed ECDM supplies a novel numerical modelling approach for investigating multicrack failure mechanism in fibre composites.