On the strength of polymeric composites exposed to long-term Ultra-Violent radiation

The widespread use of fiber reinforced composites (FRP) in outdoor applications has prompted the question that whether ultraviolet radiation could wreak havoc on their lifespan. The main objective of this study is to investigate mechanical degradation of FRPs exposed to sunlight under natural circumstances on the long-term basis. On the one hand, experimental study is performed, before and after exposure, on laminated composites with different lay-up configurations cut from FRP pipes stored in outdoor space for a 1 year. On the other hand, a simple theoretical modeling in the form of user-friendly engineering tool is developed to estimate the residual ultimate tensile strength of laminated composites after exposure to sunlight. The destructive influence of sunlight on the mechanical performance of polymeric composites is taken into account through three different stochastic scenarios. Thus, stochastic modeling is implemented and the results are compared with experimental observations.