PSI - Issue 4

Shun-Peng Zhu et al. / Procedia Structural Integrity 4 (2017) 3–10 S.P. Zhu et al. / Structural Integrity Procedia 00 (2017) 000 – 000

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Fig. 5 Fatigue reliability prediction under variable amplitude loadings Fig. 5 shows that the predictions agree well with the experimental data (VAL 1 & 2) for 45 steel. Thus, the proposed method is efficient in estimating reliability variation under cyclic loadings. This provides a simple way to model the probabilistic distribution of damage accumulation and capture the real life behavior of materials. Moreover, it can be extended for other distributions.

4 Conclusions

In this paper, a probabilistic approach for modeling damage accumulation is developed to analyze the fatigue reliability using one-to-one PDF transformation technique. It captures the real life behavior of railway axle steels by using a nonlinear fatigue damage accumulation rule. Fatigue reliability analysis was conducted under variable amplitude loadings. Further validation is required for multi-axial fatigue loading conditions. Moreover, extensive work on probabilistic methods and tools are still needed when dealing with different types of uncertainties in fatigue design and/or assessment of railway axles.

Acknowledgements

The present work was partially supported by the National Natural Science Foundation of China under the contract No. 11302044 and 11672070.

References

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