Application of continuum damage mechanics model for composites in progressive failure prediction of bolted joints

Abstract

A continuum damage mechanics model for composites, considering the intralaminar (fibre and matrix failure) and interlaminar failure, was proposed to predict the progressive damage behavior of bolted joints. Based on Tsai-Wu strength criterion, a new failure-judgement formula was developed to distinguish the intralaminar and interlaminar failure. An exponent material degradation model was introduced to simulate the damage evolution of the composite. A continuum damage mechanics model was established to analyze the effect of 0° ply ratio and bolt diameter on the bearing characteristic of the composite bolted joints. The predicted results exhibit good agreement with the experimental results. These results show that high 0° ply ratio induces the shear-out failure of the composite bolted joints, decreasing the structural bearing capability. Increasing the bolt diameter can restrain the damage of the composite laminate and improve the bearing strength of the composite bolted joints.