The response of laminated composite plates under low-velocity impact loading

This paper is concerned with evaluation of the in-plane dimensional effect of fiber-reinforced laminated composites under low-velocity impact. (0/90/0/90), oriented cross-ply E-glass/epoxy laminates studied were manufactured and all of the material parameters of laminated composite materials were measured experimentally. The impact testing was conducted with a specially developed vertical drop-weight testing machine. Impact tests were performed at impactor masses of 135 and 2600 g and an impact velocity of 3 m/s, The Studies were carried out on plate dimensions of 150 mm x 150 mm, 150 mm x 100 mm and 150 mm x 50 mm with two opposite sides clamped and the other two free and impact load applied at the center of each plate. A numerical simulation was performed using 3DIMPACT transient dynamic finite element analysis code for calculating stresses and contact forces of the composite plates during impact along with a failure analysis for predicting the threshold of impact damage and initiation of delaminations. (C) 2002 Elsevier Science Ltd. All rights reserved.