FATIGUE CURVE APPROXIMATION USING THE DANIELS’ SEQUENCE AND MARKOV CHAIN
The possibility of using the model based on the Daniels’ sequence and the Markov chain theory for approximation of S-N fatigue curve of composite material is studied. The model allows to see the connection between static strength distribution parameters and parameter of S-N fatigue curve. Although the model is too simple and does not provide numerical coincidence with experimental fatigue test data, but it can explain existence of fatigue limit and can be used as the nonlinear regression model of S-N fatigue curve with and without the fatigue limit. Using this model we can predict changes in the fatigue curve as a consequence of changes in the static strength parameter. Numerical example is given.
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