Numerical simulations of mixed-mode II+III delamination in carbon/epoxy composite laminate

Abstract

The objective of this study is to develop a reliable finite element model to simulate the mixed-mode II+III delamination behavior using six-point bending plate (6PBP) test. Two different cases were studied, which were 6PBP specimens with 60% (6PBP(60)) and 85% (6PBP(85)) of mode III component, respectively. The delamination behavior was simulated using cohesive zone modeling. Results showed good fits between the experimental and numerical force-displacement curves for both cases. In addition, it was found that there were three and one cohesive elements in the fracture process zone of 6PBP(60) and 6PBP(85) models, respectively. Furthermore, for both cases, the first damaged node in both cases was highly mode III dominated. Not only that, the mode III and mode II components in the first two damaged nodes were different. The numerical results from this study signified that the mode ratio of the 6PBP specimens was not constant.