experimental investigation of repair of glass epoxy composite with edge and center crack by epoxy resin

The aerospace and automotive industries widely use composite materials due to their weight-to-strength ratios. one of the most significant problems with composites is repair and maintenance. this study attempts to repair glass epoxy composites. the repair process involves two stages: 1)optimization of the position of the hole and 2) repair work. to optimize the repair techniques, two distinct holes were performed: 1) at the center of the specimen and 2) at the edges of the specimen. as a result, the hole drilled at the center gives higher strength than the hole drilled at the edges. after the optimization, samples were repaired with a single hole in the center and peak loads of 60% and 90%. the cracked and delaminated areas were repaired with epoxy/hardener. the repaired samples were subjected to a three-point bending test, and the results were compared with the neat gfrp samples. the results show that the curves of the repaired samples aligned with both the post and the residual flexural strength. the residual flexural strength of the 60% and 90% peak-loaded repaired samples retains about 47% and 76%, respectively.