Prediction of damage propagation in cross-ply laminated composites subjected to uniaxial tensile loading

The damage state of cross-ply composite laminates subjected to uniaxial tensile loading was examined in this study. Matrix cracking and induced delamination have been considered as the most common modes of damage in composite laminates. Using a micromechanical approach and based on Hashin variational principles, analysis of the stress field and reduced mechanical properties of a material with two symmetric and antisymmetric patterns have been examined. In this study, using the variational approach related to the homogenization method in cross-ply composite laminates containing two 90° cracked layers with the results of the simultaneous analysis method of cracks have been compared. After that, an energy-based criterion is proposed to predict damage distribution patterns and initiation, propagation, and saturation of damage based upon energy release rate. Furthermore, in order to improve the accuracy of results, ply-refinement technique has been used. By comparing the analytical results and the numerical results obtained from the finite element software, it was observed that using the ply-refinement technique has a great impact on the final results and is in good agreement with the results obtained from the finite element method.