Co-authors​ :

 John JOHN P DEAR (UNITED KINGDOM) 

Restoring the structural integrity of composite structures through repair, that have been impacted or damaged in some way, is attracting considerable interest from both industry and academia. To predict the response of patch-repaired composite laminates under low velocity impact, an elastic-plastic (E-P), three-dimensional (3-D) damage model, which accounts for both intralaminar and interlaminar damage, has been developed. Experimental data, extracted from drop-weight impact studies, performed on pristine and patch-repaired composites, are researched and compared with modelling predictions. The 3-D E-P damage model predicts the load versus time and the load versus displacement responses of the composite during the impact event. In particular, the modelling predicts the extent, shape and direction of any intralaminar damage and interlaminar delaminations, i.e. interlaminar cracking, as a function of the depth through the thickness of the impacted CFRP test specimen, as well as the extent of permanent indention caused by the impactor striking the composite plate. This is both for pristine and patch-repaired panels.