Experimental and Simulative Investigation on the Mechanical Behavior of GFRP T-joints Subjected to Low-Velocity-impact and Post-Impact Tensile Loading

To investigate the failure mechanism of the composite T-joints subjected to low-velocity-impact (LVI) loading varying impact locations, a methodology composed of improved conventional vacuum-assisted resin infusion (VARI) and LVI testing based on ASTM D 7136 is developed and employed. Moreover, the simulation is conducted to mainly reveal the damage evolution of interlaminar delamination between web and web/skin laminate based on surface-based cohesive behavior in the commercial software of Abaqus 2020. Further, the effect of LVI loading with various distances from the web laminate to the impact location on the mechanical property and failure mode of the composite T-joints are presented and discussed as well. By comparison, larger vertical cracks and higher residual tensile strength are found in the T-joints impacting the corner. However, the T-joints with the impact point near the corner have lower residual tensile strength and suffer more interlaminar delamination in the interface between web and skin, which is the most critical position of failure.