Progressive damage analysis of open-hole composite laminates under compression load

Firstly, compressional experiments were conducted on open-hole composite laminates. The progressive damage during the loading process and the final damage mode of the specimen were detected with a digital microscope, scanning electron miroscope and an X-scan equipment. Damage initiation and delamination between layups of 45° and 90° were observed during the experiments. Secondly, the failure modes of composite laminates are divided into intra-laminar failure and inter-laminar failure. A multiscale model based on the micro-mechanics of failure MMF3 theory and the interface cohesive element method for the damage analysis of open-hole compression laminates was developed. At last, the initiation and propagation of the damage and the failure modes of the laminates were predicted with the model. Numerical results such as the damage initiation position of fiber and matrix, the delamination propagation process and the final failure modes are in good agreement with experimental results, which indicates that the model is applicable to analysis of progressive damage of open-hole composite laminates under compression load.