Fatigue damage mechanics of composite materials II: a damage growth model

A fatigue model has been developed for damage growth at a notch tip in carbon fibre/epoxy laminates. The damage is modelled as a series of interacting matrix cracks in various forms: splitting, delamination and transverse ply cracking. The extent of fatigue damage can be successfully predicted for a family of (90i/0j)ns and (90/±45/0)s laminates. In this second paper of four, a damage-based model is proposed which can explain the effect of cyclic tensile loading on the post-fatigue strength and stiffness of a notched laminate