The in situ matrix cracking behavior in cross-ply laminates under out-of-plane shear loading

摘要

The in situ effect on cross-ply laminates under out-of-plane shear loading is firstly studied with a twodimensional RVE-based computational micromechanics method. High fidelity simulations of the interface debounding and crack propagation in laminates are performed, which shows good consistency with experimental observation. The matrix cracking behaviors and micro-mechanical response demonstrate that an in situ effect exists in cross-ply composites under out-of-plane shearing. Specifically, thinner ply laminates provide higher shear strength and stronger damage resistance due to the delay effect of transverse cracking and delamination. The analytical predictions on interlaminar shear strength of cross-ply laminates agree well with the existing theoretical criteria. A parametric study is performed to explore the possibility of acquiring stronger fiber-reinforced composites. The coupled load analysis sheds useful insights on the failure mechanism and optimization design of multi-layer composites.