Fatigue Damage Due to Non‐Gaussian Responses

Abstract

A formula for fatigue damage under stationary, weakly non-Gaussian responses is presented. The derivation makes use of the joint probability density function of the stress and its time-derivative given as a Charlier serie in the cumulants. The probability distribution function of the stress amplitudes is estimated assuming a narrow-banded spectrum and taking the average of the peak and trough distribution. The derived result is compared to other existing formulas and two examples illustrate the significance of small non-linearities on the fatigue damage estimate.