Failure criteria assessment of composite materials via micromechanics modelling under multiaxial loading conditions

This study assessed the widely used Tasi-Wu and Hashin failure criteria, using high- fidelity finite element-based analysis. Three-dimensional representative volume element models of IM7/8552 CFRP unidirectional composites subjected to biaxial loadings via periodic boundary conditions were constructed. The Drucker-Prager plastic damage constitutive model and cohesive zone model were utilised to simulate the mechanical response of the matrix and fibre- matrix interfaces, respectively. The RVE models were validated with experimental results from literature under uniaxial loadings and combined transverse and in-plane shear loads. Numerical simulations under (i) biaxial transverse and out-of-plane loadings and (ii) biaxial in-plane shear loading conditions, were selected in this paper for the assessment of these criteria and associated failure modes. Data-driven failure envelopes for composites under biaxial loadings were developed using a univariate spline function. It was found that micromechanics-based numerical modelling was an effective way to assess existing criteria with failure mode information.