Abstract
We have proposed a general and rigorous accelerated testing methodology (ATM) which can be applied to the life prediction of CFRP laminates and structures. The most important condition for ATM is the fact that the time and temperature dependence on the strength of CFRP is controlled by the viscoelasticity of matrix resin and that the long-term strength of CFRP can be predicted by using the short-term strength measured at elevated temperatures based on the time-temperature superposition principle for the viscoelasticity of matrix resin. The viscoelastic behavior of matrix resins depends on the water absorption, therefore the long-term strength of CFRP also depends on the water absorption. The static strengths for typical four directions of unidirectional CFRP were measured under various temperatures at a single loading rate for Dry and Wet conditions. As results, the master curves of long-term static strengths in these four directions of unidirectional CFRP were obtained for Dry and Wet conditions. The effect of water absorption on these long-term static strengths was characterized by the viscoelastic behavior of matrix resin and the failure mode.
