Effects of Edge Impact Damage on Compressive Strength of Carbon-Fiber-Reinforced-Plastic Laminates

In order to design composite structures and to improve material characteristics, impact damage on the surface and on the edge are considered. However, knowledge about the impact on the edge is limited when compared to that about the surface. In this study, edge impact tests and compressive strength tests after edge impact (CAEI) were carried out using carbon-fiber-reinforced-plastic laminates. Furthermore, CAEI failure mechanisms were investigated by measuring results using a high-speed camera and the digital image correlation method. Test results showed that the specimen with the edge impact showed about 40% lower failure load than that with no damage. According to the observation results, delamination caused by local buckling in the damage area did not seem to propagate. On the other hand, final failure occurred in the initial damage area as the starting point, and then, the in-plane failure propagated from the initial damage area to the other side in the width direction instantly. The in-plane residual strength after edge impact as well as delamination seemed to affect the final failure.