Probabilistic interval geometrically nonlinear analysis for structures

This paper presents a new unified Chebyshev surrogate model based hybrid uncertainty analysis method for robustly assessing geometrically nonlinear responses of engineering structures involving both random and interval uncertainties. In this proposed approach, Chebyshev response surface strategy combined with finite element framework is developed to model the nonlinear relationships between the uncertain structural parameters and the corresponding system responses. A comprehensive computational analysis framework, namely generalized unified interval stochastic sampling, is devised to furnish the statistical features, including means, standard deviations, probability density functions and cumulative distribution functions, of the lower and upper bounds of the nonlinear random interval structural behaviours. The applicability and notable performance of the presented approach are elucidated with the help of two practically motivated examples.