A Model for Predicting the Residual Strength of GFRP Laminates Subject to Ballistic Impact

Abstract

This work is concerned with the tensile residual strength of s-glass/epoxy (Fiberite, Hy-E 9134B) laminates subject to ballistic impact. A total of twenty-four tests are conducted in order to study the impact residual strength of a specimen struck by a nor mal incident foreign object. Depending upon the post impact behavior, a high speed fram ing camera and a set of silver short-screens are used to measure, respectively, the projec tile's rebound and post-perforation terminal velocities. A target's impact residual strength is determined using an MTS tester. A model is proposed here in order to predict the tensile residual strength of the GFRP specimens. This model is based on a combination of the target's residual strength and the kinetic energy transferred to it by the penetrator. Results calculated from this modified model are compared with test findings. The impact residual strength results predicted by the current model more closely resemble the test results than those predicted by Caprino's model. In addition, the relationship between the initial im pact and projectile terminal momentum is also reported.

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