Abstract

This work presents an efficient parametric model reduction technique together with an effective Markov chain Monte Carlo method for performing reliability analysis of complex dynamical systems such as large nonlinear finite element models under stochastic excitation. The model reduction technique is based on substructure coupling for dynamic analysis. In this framework, the dynamic behavior of the substructures is described by a set of normal modes plus a set of interface modes that account for the coupling at each interface where the substructures are connected. The interface degrees of freedom are reduced by considering a small number of characteristic constraint modes. The technique is combined with an effective adaptive finite element model parametrization scheme. The effectiveness of the proposed methodology is demonstrated by means of a numerical example involving the reliability analysis of a large three dimensional nonlinear finite element building model.