VEHICLE-BRIDGE INTERACTION ANALYSIS OF A SUPER BRIDGE IN URBAN RAILWAY SYSTEM

Vehicle-Metro-Bridge interaction analysis was conducted upon a super bridge in an urban railway system. The bridge consists of viaducts and railway lines. The numerical analysis in time domain based on the Finite Element Method was applied to the research. The FE model of the bridge was built by using a thin plate and a beam element. The analytical model of the metro has 17 degrees of freedom, of which the carriage is three-dimensional. The parameters of the metro model are determined based on the B type metro. One part of the loadings, vehicle loadings, was designed as a set of moving constant loadings in a range of situations. On the other, the Metro-Bridge interaction model was solved by using a separate iteration method, combining ANSYS and FORTRAN procedures. In this procedure, the wheel-rail interaction was assumed as a non-jump model and the track irregularity was took into consideration as well. Some analyses focused on the running smoothness of metro carriages under a set of situations, and the influence of the track irregularity upon the mid-span dynamic displacement was also discussed. The results states that viaduct and railway line interfere each other slightly. The track irregularity creates little impacts on the mid-span displacement of viaduct and railway line when metro's velocity is low. These two results can be a reference to the structural strength design of similar bridges.