Parametric Study on the Failure of Fiber-Reinforced Composite Laminates under Biaxial Tensile Load

Abstract

A numerical constitutive model for a single layer of fiber-reinforced composite laminates, including nonlinear stress–strain relations, mixed failure criterion and post failure response, is used to predict the ultimate strengths of the composite laminates under biaxial tensile loads. The nonlinear constitutive law uses a variable shear parameter to model the nonlinear behavior of the in-plane shear. The onset of failure for individual lamina is determined by a mixed failure criterion composed of the Tsai-Wu and the maximum stress criteria. After the initial damage occurs, the response of the lamina is described by brittle or degrading modes up to the collapse of the entire laminate. The constitutive model is tested against experimental data and satisfactory results are obtained. In addition, parametric studies for composite laminates with different laminate layups and under various biaxial tensile load ratios are presented.