RVE-based virtual testing for investigation of the shear behaviour of cross-ply composites

Shear properties of fibre-reinforced polymer matrix composite materials are key design parameters in many applications of these materials. Experimental data show that a shear stress-strain curve of a cross-ply composite typically contains a yielding stage followed by a nonlinearly hardening response. Here, we establish an RVE-based virtual testing framework for predicting the shear behaviour of cross-ply composites. The method is simple, computationally cheap and free of fitting parameters as it employs the crystal plasticity formulation for the constitutive modelling of plies. This framework naturally captures the rotation of fibres during the finite deformation of composite material which is shown to be responsible for the hardening response of cross-ply composites. The framework does not involve any constitutive hardening rule and thus the predicted hardening in cross-ply composites is solely related to the geometrical effects. The method is applied for two different composite materials and validated against available experimental data obtained via the +/- 45 degrees tensile test and the V-notched rail shear (VNRS) test methods. The success of the framework in predicting the shear behaviour of cross-ply composites is remarkable. Finally, a full model of the VNRS test method is constructed to address the specific features of this test configuration.

Automated summary

In this study, an RVE-based virtual testing framework was developed to predict the shear behavior of fibre-reinforced polymer matrix composite materials. The framework utilizes the crystal plasticity formulation to model the constitutive behavior of the plies and accurately captures the shear response of the composites. The method was validated on two different composite materials and successfully predicted their shear behavior.