Dynamic Analysis of Tensile Preloaded Woven Composites Under Low Velocity Impact

Abstract

In this paper, the effects of low-velocity impact on the E-Glass Epoxy woven composite laminates under tensile preload are presented. Due to the low-velocity impact loading, laminate suffers an extensive internal damage such as delaminations and the damage on the back face. The effect of preload can significantly change the impact behavior and progressive damage mechanics. Therefore the study of impact damage susceptibility of these woven composite laminates under tensile preload (corresponding to tensile strain) is increasingly important. While considerable experimental and analytical studies have been made on the low velocity impact phenomenon, very little work is reported in the area of effect of preloads on the damage mechanics for E-Glass Epoxy woven composite laminates subjected to low velocity impact. A detailed finite element mosaic model was developed using Virtual Proving Ground (VPG) software. Dynamic analysis was performed using LSDYNA® finite element software. A plate consisting of 10 layers of E-Glass/EPON 862-W (10EG) was modeled using three dimensional orthotropic elastic brick elements. Preload boundary conditions were simulated using in-plane displacement for three different incremental values (0.08% strain, 0.16% strain and 0.24% strain) representing realistic assembly conditions. The simulation results were compared for their maximum load carrying capacity. It was observed that with increase in preload, laminate looses its maximum load carrying capacity.