Modulus reduction and fatigue damage of matrix dominated composite laminates

Abstract Through the monitoring of fatigue modulus degradation, the cumulative damage of matrix dominated composite laminates due to fatigue can be evaluated. A fatigue modulus degradation model is presented in this paper to predict statistical distributions of fatigue modulus reduction for matrix dominated composites. Regression analysis and Bayesian statistical approach are used with the aid of the model to forecast the fatigue modulus reduction for an individual specimen. Experimental tests were performed on the [±45°]2s graphite/epoxy laminate to generate statistically meaningful data for verifying the model. It is shown that the predictions using the fatigue modulus degradation model correlate well with the experimental results.

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