Residual performance of scarf patch-repaired pultruded shapes initially impact damaged

This paper presents an experimental investigation on the residual mechanical behaviour of patch-repaired composite pultruded structures initially submitted to low-velocity impact loading. It reports detailed results about static, fatigue and impact tests performed on different glass/polyester impact-damaged structures repaired by low-cost and manual techniques. All the tests were conducted at room temperature. It appears that, firstly, for all the studied structures, the initial static strength is completely recovered. Secondly, for two types of pultruded structures, the fatigue crack-growth life does not recover its initial values but compared with the damaged specimen, the lifetime is significantly enhanced. Residual performances of both undamaged and repaired specimens seemed to be influenced by the profile geometry (in fatigue bending tests) and especially by the open/closed characteristic of the structures. Carefully designed, external scarf patch repairs can recover more than 85% of the undamaged mechanical behaviour, depending on the type of residual applied loading.