Fatigue life study of laminated composites carbon-epoxy manufactured from unidirectional plies and 2D-woven plies combining thermo-mechanical analysis and a residual strength model
Résumé
Long-term durability under repeated mechanical loading is a major criterion for design of composite structures. The development of a fatigue criterion faces two major difficulties: (i) the proposal of a load/life curve (S-N curve) describing the natural dispersion of the fatigue tests and (ii) the duration of these tests. The goal of the study is to combine the Sendeckyj's approach based on a so-called residual strength that fits S-N curve and associates a failure probability [1], and a self-heating-based method that estimate a mean S-N curve from the thermal dissipation, determined from temperature measurements on a single sample [2]. The fatigue lifetime for high cycles loading is estimated by the heat-build up protocol. Quasi-static tests and a few fatigue tests are used to estimate the failure distribution based on a two-parameters Weibull model.