Determination of fatigue response of composite circular beam through a new coupled progressive fatigue damage model

Fatigue behavior of fiber reinforced composites is still difficult to analyze or understand to be determined. It is due to various parameters affecting and their complicated interactions which come from the constituents’ physical and mechanical behavior. Hence, conducting experiments and developing fatigue models are necessary in determination of fatigue behavior in many cases. On the other hand, complicated behaviors lead the application of composite materials to be accomplished with a number of experiments and/or including high safety factors in design calculations in both the process may not be cost effective. This paper introduces a new algorithm and model to determine fatigue response of damaged circular composite beam. The results are evaluated by experimental results. By using the proposed model, the number of experiments and the time needed to determine fatigue behavior of damaged circular beams are significantly reduced. To determine the constants introduced in the local fatigue damage model, cyclic tests are performed up to limited load cycles. The predicted results by the model and obtained from the experiments represent satisfactorily good agreements.