Numerical analysis of fatigue evolution of laminated composites using cohesive zone model and extended finite element method

A numerical method for fatigue accumulation of in laminated composites is developed in this paper. Extended finite element method (XFEM) and cohesive element are integrated into a numerical program for modelling intralaminar matrix cracking and delamination in composite laminates, respectively. A damage-mechanics-based fatigue model is also introduced into the numerical scheme. Pure modes fatigue tests are used for the identification of fatigue parameters. The simulation of open hole tensile test is then performed to investigate the fatigue behaviors of composite laminates. The numerical damage distribution aligns with prior test records, while the predicted fatigue life is consistent with the referenced data. The fast crack propagation observed in the reference is also captured. This study demonstrates that the proposed numerical method can predict the fatigue initiation and evolution of multi-cracks under mixed mode loading. This paper introduces a convenient approach to effectively simulate multiple fatigue cracks in composite laminates.