Lifetime prediction of aluminium structures reinforced with composite patches

The paper deals with the lifetime prediction of aluminium structures reinforced with composite patches. Load-controlled fatigue tests have been carried out on 2024-T3 aluminium specimens. First the scatter of aluminium fatigue properties is analysed. Damaged holed structures are then patched and their experimental fatigue behaviour is compared to the fatigue response of unpatched specimens. It is shown that the adhesive governs the fatigue response of the reinforced specimens for high load levels. A lifetime prediction method is then developed to assess the residual lifetime of damaged reinforced structures. The method is based on the intrinsic material fatigue properties and on the damage level attained when the aluminium specimens are reinforced with composite patches. Finally a comparison between experimental and theoretical results is performed. It is observed that the Mesmacque sequential law gives the most accurate lifetime prediction of the reinforced aluminium specimens.