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.