Rain-flow fatigue damage for transformed Gaussian loads

Fatigue damage due to a special class of non-Gaussian broadband loadings is considered. Specifically, the loadings are considered to be non-monotonic transformation of stationary, Gaussian random processes. A linear damage accumulation rule is assumed and the rain-flow cycle counting method is considered. Analytical expressions are developed for estimating the expected rain-flow fatigue damage. Easy to compute approximations, in terms of the upper bounds for the expected rain-flow fatigue damage, have been developed. The proposed method has been demonstrated through a set of illustrative numerical examples. The method developed is of use in estimating the time variant reliability of ageing structures under random dynamic loadings. (c) 2006 Elsevier Ltd. All rights reserved.