Fatigue life assessment in non-Gaussian random loadings

This paper treats the theoretical fatigue analysis of non-Gaussian random loadings. It first reviews a method recently developed by the Authors, which is capable to account for the effect of load bandwidth and non-normality. Fatigue lives from simulated Gaussian and non-Gaussian loadings, as well as data from experiments taken from the literature, are compared with theoretical estimations. The non-Gaussian loading was modelled as a transformed Gaussian process. The results show how the load non-normality has a great effect on both the cycle distribution and the fatigue damage; the proposed method seems able to account for this effect correctly. Furthermore, the theoretical predictions are shown to be substantially comparable (with some exceptions) with the experimental data.

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