EXPERIMENT RESEARCH AND FATIGUE LIFE PREDICTION OF LOW-VELOCITY-IMPACTED LAMINATE UNDER COMPRESSIVE-COMPRESSIVE FATIGUE LOAD

Low velocity impact and post-impacted compression-compression fatigue tests of composite laminates were performed. After measuring the damage area in detail, the paper proposed the rule of damage propagation in compression-compression fatigue tests. The impact damage was considered as a circle hole, and a special finite element including an elliptic inclusion was adopted to analyze the stress distribution. Base on the damage propagation rule, characteristic length and point stress criterion were used for predicting the compression-compression fatigue life of post-impacted laminates. A good agreement is observed between the computational and experimental results. In addition, this model can also be applied to predict the residual compressive strength of damaged laminates under fatigue loads.