Steel Arch Bridge With Vehicle Vibration Visualization Simulation Study

The purpose of this paper is to use a visualization approach to simulate the dynamic response of a framed arch bridge under moving vehicle loads. Firstly, Models are developed for vehicles, road surface (roughness) and the bridge. Jinhuai Bridge is modeled as a planar bar system by 112 beam elements. The vehicle is simulated by a 2-D sprung mass system with four degrees of freedom according to a typical truck. The surface irregularity of the bridge pavement is considered as a stationary random process characterized by a power spectral density function (PSDF) of the surface irregularity. The irregular profile of the bridge pavement is generated from the PSDF using Monte Carlo simulation technique for very good, good, and average roads according to GB7031-86 specifications.A new numerical procedure for analyzing the coupled vibration of a framed arch bridge with a single moving vehicle is presented to solve the equations of motion of a bridge with many degrees of freedom. The procedure consists in dividing the bridge-vehicle systems, which are solved separately, into 2 subsystems at the interface of the bridge and vehicle. The compatibility at the interface is obtained by an iterative procedure with Aitken acceleration. Based on the above numerical procedure, parameter study, including the vehicle velocity, damping of the bridge, road surface roughness, and constrained freedom of the bridge, is conducted to investigate the influence of some important bridge and vehicle parameters on the impact ratio of the bridge.For recently there are some different opinions about the mechanism of bridge resonant vibration excited by moving vehicles, further study is done in this paper to analyze the dynamic response of Jinhuai Bridge under multiple vehicles with different velocity, moving direction and distance between two adjacent vehicles. From the results, we can see that Jinhuai Bridge has no noticeable vertical deflection peak. It is mainly because of the restrictions of some parameters such as velocity of the vehicle on highway and damping of the bridge, which can limit the peak values.Based on the principle and method of computing visualization, an easily implementing procedure for dynamic graphic description is proposed. A two-dimensional model of Jinhuai Bridge has been established in the paper with OpenGL as graphic tool, and a high-resolution animated cartoon simulation of Jinhuai Bridge under the moving vehicles has been accomplished.