Study On Performance Matching Of Wheel-Rail Dyanmic Interaction On Curved Track Of Speed-Raised And High-Speed Railways

With the increase of train speeds and the development of high-speed railway, the wheel-rail interaction on the curved track will unavoidably be reinforced, as requires more advanced technique to match the wheel-rail dynamic performance. So, from the point view of the wheel-rail coupled dynamics, this thesis tries to investigate the performance matching of wheel-rail dynamic interaction on the curved track of the speed-raised and high-speed railways.Firstly, based on the theory of the wheel-rail coupled dynamics, this thesis puts forward the technique of the performance matching of wheel-rail dynamic interaction on the curved track of the speed-raised and high-speed railways, which includes the model of the wheel-rail dynamic performance of curve negotiation, the geometric contact relationship of measured wheel/rail profiles, the TTISIM simulation software of vehicle-track coupled dynamics, the evaluation and standard of main indices of dynamic performance, and the principle of the performance matching as well as the research framework.Secondly, the effects of the vibration and parameters of track structure on the performance of curve negotiation are analyzed, and the influence of the rail twist on wheel-rail dynamic interaction on the curved track is also discussed. Results show that, the values of indices simulated by the model with track vibration are lower than thoses by the model without track vibration. For the model with track vibration, dynamic results without consideration of the rail twist are bigger than those being taken the rail twist into account and the difference in the results is lower than10%, and the factors, including the lateral and vertical stiffness of the rail pad, have much effect on the dynamic performance of curve negotiation.Applied this technique of the performance matching, the research on the wheel-rail dynamic performance on the curved track of speed-raised lines is carried out. Results show that when speed-raised trains pass through curved tracks, the lateral dynamic interaction between wheels and rails will be enhanced. Under the condition of the traction, the value and the direction of the creep force in longitudinal can be changed, as affects the wheel-rail dynamic performance. If the speed of train is raised to200-250km/h, the wheel load will reduce obviously. The main reason is that there are track irregularities with the wavelength ranging from1m to2.5m. So, to reduce the amplitude of this type of track irregularities can help to improve the running safety of train. This part of the theory study will provide the theoretic support for the project of raising speed on existing railway lines. Then, the dynamic performance of small-radius curved track for mountain strengthened railway is investigated with the method of theory and experiment. Results show that the strengthened track can help to decrease the displacements of all components of track structures obviously, to reinforce the stability of the line, and to reduce the maintenance workload of railway. This part of the study will supply the theoretic and experimental support for the project of proposing measures and popularizing applications of the strengthened track.Lastly, an investigation on the wheel-rail dynamic performance on the curved track of high-speed railway is carried out. Results show that, the area of wheel-rail contact in outer rail is bigger than that in inner rail. Excited by the rail corrugation, the dynamic interaction of the curved track will inevitably be enhanced. Excited by the random irregularity, all of the safety and comfort performance can meet the requirements if the lap length of the plan and profile section is zero. Additionally, taking an engineering of dedicated passenger line (Guangzhou-Shenzhen-Hongkong) for an example, the application of the technique of the performance matching is introduced in the scheme comparison of plan and profile section.