Stationary Random Vibration Analysis of Dynamic Vehicle-Bridge Interaction Due to Road Unevenness

This article presents stationary random vibration analysis of dynamic vehicle-bridge interaction due to road unevenness based on the Finite element method and Monte-Carlo simulation method. The road unevenness are described by a zero-mean stationary Gaussian random process. The vehicle is a dumper truck with three axles. Each axle of vehicle is idealised as two mass dynamic system, in which a mass is supported by a spring and a dashpot. The structural bridges are simulated as bending beam elements. The finite element method is applied to established the overall model of vehicle-bridge interaction. Galerkin method and Green theory are used to discrete the motion equation of vehicle-bridge system in space domain. Solutions of the motion equations are solved by Runge-Kutta-Mersion method (RKM) in time domain. The numerical results are in good agreement field test results of the prestressed beam-slab at Nguyen-Tri-Phuong bridge, Danang city, Vietnam. Also, the effects of road surface condition on dynamic impact factor of bridge are investigated detail. The numerical results show that dynamic impact factor of bridge has increased significantly when road unevenness have changed from Grade A-road to Grade E-road according to ISO 8608:1995 [1] “Mechanical vibration—Road surface profiles—Reporting of measured data”.