Abstract
A highly efficient numerical approach: extended cohesive damage model (ECDM) for predicting multicrack propagation is introduced in this paper. The ECDM is developed within the framework of the eXtended Finite Element Method (XFEM). Unlike XFEM the enriched degrees of freedom (DoFs) are eliminated from the final condensed equilibrium equations in the ECDM. To account for the cohesive crack effect, an equivalent damage scalar relating to a strain field is introduced in terms of energy dissipation. The ECDM is capable of characterizing discontinuities with conventional DoFs only, thus it is significantly efficient in modelling multicrack propagation. The basic formulations, numerical implementation and detailed investigation of the performance of the ECDM through modelling the selected benchmark specimens are given in this paper. This investigation shows the ECDM can effectively guarantee the convergent solutions in nonlinear fracture analysis and can efficiently reduce the computer CPU time in modelling selected fracture benchmark specimens by more than 60% compared to the XFEM in ABAQUS. Therefore, the ECDM is a robust computational approach for predicting multicrack failure mechanism in engineering materials and structures.