Quantification of uncertainty in metallic elements subjected to fatigue

Abstract

This investigation analyzes the propagation of the uncertainty of the number of life cycles to fatigue failure, taking into account the strain life method, considering as random variables some parameters of the material and loading in a steel plate under fatigue, with constant and variable loading through multidimensional Hermite polynomials. The application of series of multidimensional Hermite polynomials allowed the prediction of the randomness of the output vector. This research has shown that a multidimensional Hermite polynomial adequately estimates the propagation of the uncertainty of the input random variables. The results showed that variations in material and loading parameters can generate important failure probabilities and allowed quantifying the variability in the number of life cycles for fatigue failure steel parts