Experimental observations and numerical simulations of curved crack propagation in laminated fiber composites

Abstract Fracture experiments were carried out on continuous fiber polymer matrix laminated composite panels to investigate cohesive, through-the-thickness crack propagation. The experiments were designed to examine curved cracks, resulting from either eccentric loading or non-symmetric specimen geometry with respect to the starter crack. The constitutive description of the observed complex diffused damage zone, which from a continuum viewpoint may be considered a macroscopic crack, involves complex/evolving traction–separation relations and mode-mixity conditions. This paper presents some relevant experimental investigations and their numerical modeling using the variational multiscale cohesive method developed by Rudraraju et al. [21] which is an effective framework for simulating cohesive crack evolution and thereby predicting the residual strength of cracked composite panels.