On matrix crack growth in quasi-isotropic laminates - II. Finite element analysis

Multiple matrix crack growth behaviour in a quasi-isotropic (0/90/ - 45/ + 45), laminate has been simulated by using generalised plane-strain finite element models. Representative models have been developed to describe the sequential matrix cracking events observed from the experiments, as reported in Part I of this paper. These models provide quantitative predictions of stiffness reduction due to matrix cracking which are in good agreement with the experimental results. These results show that 90 degrees and + 45 degrees cracking are the major damage events governing the degradation of the laminate elastic properties with the contribution from the -45 degrees cracking being less important. The models provide information concerning stress distributions in the vicinity of existing cracks, which enable the transfer lengths for cracks in the 90 degrees ply to be estimated and may facilitate the study of failure mechanisms at the local level. (C) 1997 Elsevier Science Limited.