Realistic Modelling for Analysis of Train-Structure and Ballasted-Track Interaction for High-Speed Trains

PurposeIn this study, a new train-track-bridge interaction system (TTBIS) is modelled, and the interaction of the system is analysed to calculate the dynamic responses of the (TTBIS). Considering the lateral and vertical dynamic movements, the entire train is realistically modelled with 31 degrees of freedom.MethodsThe track system is realistically modelled as flexible rail, and the infrastructure system supporting the rail with eight parameters. So, the track system consists of flexible rail, two parameter rail pad, sleeper, ballast parameters. The bridge was modelled using thin beam theory and integrated motion equation was obtained using the Lagrange method.The analytical solution of motion equation was conducted by setting up an algorithm using the Runge-Kutta method with a specially written code.ResultsAs a result of the analyses made, the length of the bridge is 50 m or less, which does not affect the vertical movements of the train. In addition, Thanks to the track system, the dynamic responses affecting the train have been reduced. It is also understood that the vertical dynamic behavior of the train is a minimum in every four wagons.ConclusionAs the significance of this research, it was seen that bridge flexibility, natural vibration frequency, track parameters, travel speed, and the number of wagons have essential effects in terms of safe travel of high-speed-train.