Safety and Stability of Light-Rail Train Running on Multispan Bridges with Deformation

This study investigated the safety and stability of light-rail trains that run on multispan simply supported bridges (MSSBs) and have experienced some settling and girder deformation caused by both foundation settlement and girder deflection/camber. A three-dimensional dynamic nonlinear finite-element model for a light-rail train track-MSSB interaction system, which took into account rail irregularities, girder deformation, wheel-rail contact, and coupling effects, was developed. A case study analyzed a four-car light-rail train rolling on a MSSB, and the relationships between the girder deformation and running performance under various speeds were obtained. The results indicate that speed is the dominant factor that contributes to the safety and stability of the light-rail train when girder deformation is present. In addition, the influence of girder deformation was found to be greater on safety than on stability. In real applications, it is recommended to pursue advanced monitoring and evaluation techniques for safe operation of light-rail train systems.