Prediction of the strength parameter of cohesive zone model for simulating composite delamination by the equivalent inclusion method

Abstract

The cohesive strength is an important parameter in numerically modeling composite delamination via cohesive zone model-based FEM. A micromechanical model is proposed to predict the cohesive strength based on Eshelby's equivalent inclusion method (EIM). In this model, it is considered that the cohesive strength depends heavily on the stress concentrations at the microscopic level. The cohesive strengths of T700/QY8911 and AS4/PEEK laminates at various cross-angles of the bidirectional fibers are computed using EIM with constant eigenstrains. With the predicted cohesive strengths the FEM simulations on mixed-mode bending and six-point bending test are presented, and the results are in fair agreement with experimental observation. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers