Progressive failure analysis of composite laminates using 3-D finite element method

Progressive failure analysis was conducted in the present study for the cross-pry and quasi-isotropic laminates subjected to axial extension. Stresses and strains are calculated by the 3-d finite element method based on the generalized layerwise plate theory (GLPT) in order to consider the local effect near the free edges. The types and size of damage in composite laminates are predicted in the failure analysis that consist of a set of failure criteria and property degradation models for each mode of failure. In case of matrix cracking, the macroscopic stiffness reduction model based on the shear-lag method is introduced to the finite element method in order to consider nonlinear reduction of stiffness at each strain level. Mesh refinement is conducted both in-plane and through the thickness direction in order to predict the failure load and the damage accumulation accurately. The failure mechanism and ultimate failure loads of the cross-ply and quasi-isotropic laminates for different stacking sequences with the same thickness are investigated.