Damage evaluation of structures with uncertain parameters via interval analysis and FE model updating methods

Experimental and numerical uncertainties are always present in structural identification problems. The quantification of the uncertainty on the results of a finite element updating procedure is commonly carried out in a probabilistic framework, which requires working with a-priori known probability distributions for the uncertain parameters. In this paper, the modal interval analysis method to estimate damage structural problems with uncertain-but-bounded parameters is presented. With this method only the bounds on the magnitude of uncertain parameters are required. The formulation of this method in a single objective framework is equivalent to minimizing the average value and the deviation of the uncertain objective function in the considered interval with which it is actually a multi-objective problem. Furthermore, its implementation requires the analytical evaluation of the sensitivities of the objective functions with respect to the uncertain parameters, which is derived. Numerical and experimental results evidence the accuracy and the effectiveness of the proposed approach to evaluate damage in uncertain environments. Copyright (c) 2016 John Wiley & Sons, Ltd.