Dynamic analysis of bridge with non-Gaussian uncertainties under a moving vehicle

An analysis method on the bridge–vehicle interaction problem with uncertainties is proposed. The bridge is modeled as a simply supported Euler–Bernoulli beam with non-Gaussian material parameters with a vehicle moving on top modeled by a deterministic four degrees-of-freedom mass–spring system. The non-Gaussian uncertainty in bridge is modeled by the Spectral Stochastic Finite Element Method (Ghanem and Spanos (1991) [17]), and the mathematical model of the coupled bridge–vehicle system, with the road surface roughness assumed as a Gaussian random process, will be solved by the Newmark- β method. The proposed model is verified by the Monte Carlo Simulation with numerical examples. Different levels of uncertainties in both the excitation and system parameters are investigated. Criteria on the selection of both the order of Polynomial Chaos and the threshold for truncation in the Karhunen–Loève expansion are provided. Results show that the proposed algorithm is promising for the dynamic analysis of the bridge–vehicle interaction problem even with a high level of system and excitation uncertainties.