Evaluation of failure criteria for composite plates under tension

Abstract

This paper aims to explore the built-in failure criteria functions provided by ANSYS to simulate the failure behaviour of composite plates under tension. The first ply failure (FPF) load is determined and the results are used for the time to assess the accuracy of the available built-in failure criteria. Finite element (FE) models are developed using standard ANSYS formulation to replicate physical uni-axial tensile tests. The built-in failure criteria functions are explored and the available criteria (Maximum Stress and Tsai-Wu Failure Criteria) are used to determine the FPF load for a composite laminate, with a layup of (θ4/04/- θ4)s. The angle, θ, is varied from 0° to 90°. The results are compared with a (FE) implementation using Fortran and available experiment data. The FPF curves for both ANSYS and Fortran were plotted and found very close to the experiment results. By comparing the curves, the results are used to assess and evaluate the accuracy of the failure criteria. The results show that the current ANSYS and Fortran simulations produce a maximum average error of 16%. Using ANSYS, the Maximum Stress and Tsai-Wu criteria produce an average error of 5.78%, and 13.19% respectively. Using Fortran programme, Maximum Stress produces an average error of 1.36%. Despite larger error, simulations using ANSYS allows easier modification and manipulation. Moreover, the procedure of simulations has the potential to replace tedious and expensive physical testing. Therefore, it can be concluded the current study has successfully explored the built-in failure criteria functions in ANSYS to replicate experiments. Apparently, the current study is novel, useful and contributes significant knowledge in conducting failure analysis of composite laminates.