Dynamic responses of railway suspension bridges under moving trains

This paper describes a numerical simulation technique that is used to investigate a dynamic train-long suspension bridge interaction. A three-dimensional finite element model is used to represent a long suspension bridge. Each vehicle of the train is modeled by a 27-degrees-of-freedom dynamic system, including two bogies with four wheel-sets. By applying a mode superposition technique to the bridge and taking the measured wheel and track irregularities as known quantities, the degrees of freedom of the bridge-train system are significantly reduced and the coupled equations of motion are efficiently solved. The proposed formulation and the associated computer program are then applied to a real long suspension bridge. The dynamic responses of the bridge and the train vehicles are computed and compared with the limited measured data and the results are satisfactory.Department of Civil and Environmental Engineerin