The Rotem failure criterion for fibrous laminated composite materials: Three-dimensional loading case

The present article describes the application of Rotem failure criterion to solve 12 test cases employed in the Second World-Wide Failure Exercise (WWFE-II). The criterion distinguishes between fiber failure and matrix failures (transverse-isotropic strength and the square of the deviatory and shear strengths). Effect of hydrostatic pressure is taken into account for the matrix dominated failure. The nonlinear progressive model is used to predict three-dimensional failure envelopes and stress strain curves for all 12 test cases, which involved isotropic, unidirectional lamina and multi-directional laminates loaded both through-thickness and in-plane directions. The calculation technique and the final results are given in the article.