Simplified Methods for Predicting Fatigue Life of Composite Material Structures

As part of the design procedure for fiber reinforced composite structures, it is important to be able to predict the fatigue life and the residual strength of the structure under representative repetitive fatigue loads, including the relevant environmental exposure factors during service. This paper presents some empirically based methods for analytically predicting the fatigue life and residual strength of fiber reinforced composite structures, based on the "no-growth" fatigue life approach, and on experimental static and fatigue test data. The aim here is to consider some of the simpler analytical approaches possible. Also discussed herein, is a coupon fatigue test program for CFRP material that is under way at IAI, in order to evaluate alternative analytical procedures.