A new cumulative fatigue damage model for fibre-reinforced plastics

A cumulative fatigue damage model is presented for predicting the fatigue life of fibre-reinforced plastics (FRP) subjected to variable amplitude fatigue loading. It is assumed that the cumulative fatigue damage caused by the cyclic loading is proportional to the strength loss of FRP, and that the damage state in laminates can be described phenomenologically by residual strength. Some experimental results from two-stress level and block spectrums are employed to evaluate the model. Good coincidence between experiment and theory has been obtained for GRP and CFRP.