Analysis of Progressive Matrix Cracking in Composite Laminates

摘要

This report summarizes recent results of studies on progressive ply cracking in fibrous laminates. Evaluation of stiffness changes caused by systems of aligned slit cracks which are parallel to the fiber direction in a unidirectional composite lamina is discussed. Results obtained by the self-consistent method are presented. Next, a procedure for estimating instantaneous crack densities and stiffness changes in a lamina subjected to a prescribed strain history is outlined. These results are extended to analysis of laminated composite plates under in-plane stresses. Specific examples and comparisons of analytical and experimental results are presented for two graphite-epoxy systems.