The implementation of the extended cohesive damage model for multicrack evolution in laminated composites

In this work, the extended cohesive damage model (ECDM) was implemented to investigate the multicrack evolution in laminated composites. The ECDM was developed in terms of the framework of the extended fine element method (XFEM), but unlike the XFEM, the enriched effect to approximate existing crack together with the cohesive effect to approximate the crack tip behaviour was directly accounted into an equivalent stiffness matrix. A new damage scale relating to strain field was introduced to account for delamination and matrix crack while the quasi-brittle failure mechanism was assumed for fibre fracture. The special mesh treatment for simulating interlaminar delamination required by conventional cohesive zone model (CZM) is no longer required by the ECDM. Examples given in this paper proved the capability of the ECDM in capturing the multicrack evolution. This developed ECDM provides a novel modelling approach to investigate detailed multicrack failure mechanism in laminated composites.