Fatigue analysis of wind excited structures with structural parameters affected by uncertainties described by interval variables

摘要

In this paper, the fatigue analysis of linear structures with uncertain-but-bounded parameters subjected to stationary multi-correlated stochastic excitations is addressed. To perform this analysis, approximate expressions of the bounds of the interval spectral moments of stress quantities are first evaluated. Since the definition of the interval stress spectral moments involves double occurrences of interval variables, a novel approach is here presented in order to overcome the so-called dependency phenomenon, which often leads to an overestimation of the interval solution width unacceptable from an engineering point of view. Then, the bounds of the expected fatigue life are evaluated by combining the method proposed by Benasciutti and Tovo with the improved interval analysis via extra unitary interval, recently developed by the last two authors.