Numerical investigation into multi-delamination failure of composite t-piece specimens under mixed mode loading using a modified cohesive model

The failure mechanism of fibre composite T-piece specimens under mixed mode loading was investigated for the first time by simulating multi-delamination using a modified cohesive model with a new coupled damage scale introduced. The new damage scale extended the cohesive model to accommodate mixed damage accumulation. It revealed the interaction between tensile and bending in a mixed mode loading case plays an important role in the failure mechanism. This work forms the basis for a new proposal to EPSRC for developing an extended finite cohesive element enriched by a mixed damage scale.