Research On Line Design Parameters Of Higher Speed Wheel-Rail High-Speed Railway Based On Comfort Evaluation

With the continuous improvement of high-speed railway operating speed,the dynamic interaction between train and line is significantly enhanced.Train running safety,running stability and passenger riding comfort are more prominent under the influence of line parameters at higher speed levels,including the setting of minimum curve radius,elevation and length of easing curve will directly affect the dynamic performance of running train.Traditional specifications for the design of horizontal profile parameters of lines 350km/h and below will be affected and challenged,and the applicability of their parameters needs to be further studied.Therefore,for the wheel-rail high-speed rail with 400km/h and above,while studying the existing specifications,it is of great significance to explore the parameters of main lines and analyze the comfort of passengers.Based on the established dynamic simulation model,the dynamic response analysis and the main linear indexes of the wheel-rail high-speed rail at 400km/h and above were carried out in this paper.The main research contents are as follows:(1)On the basis of the vehicle-track coupling dynamics theory,the dynamic model of the high-speed train with multi-car connection passing through the complete curve section is built by using SIMPACK software,and the dynamic characteristics of the multi-car connection model are studied.(2)According to the established vehicle body dynamics model,the influence of line parameter matching on train safety and wheel-rail force at different high speeds is analyzed,and the theoretical analysis of line parameter superelevation,radius of circular curve and length of transition curve is carried out.At the same time,the relationship between line parameters and wheel-rail contact response is analyzed by using the FASTSIM algorithm and Archard wear model under Kalker’s simplified theory,The influence rule of curve design parameter circular curve radius on wheel/rail wear related indexes including wheel wear,rail wear,wheel/rail contact spot area,longitudinal creep force,lateral creep force,wheel offset angle is studied.The difference of wheel/rail contact response between inner and outer rails,the relationship between longitudinal and lateral creep force,the relationship between wheel/rail impact angle and lateral creep force are also analyzed,and the corresponding conclusions are obtained.(3)Through the study and research on the comfort of high-speed trains,the influence of the line parameters circle curve radius,transition curve length and superelevation on ride comfort is investigated,and the vehicle running stability in the comfort evaluation index system,including the vehicle vibration acceleration,stability index,vehicle vibration comfort index,is emphatically studied,After analyzing and summarizing the changes of indicators under the condition of line parameter matching,some recommended values of line parameters for higher speed wheel-rail high-speed rail based on comfort evaluation are finally obtained.(4)The adaptability of line parameters for 400km/h operation is studied for an existing railway curve section with a target speed of 350km/h.When the vehicle speed is increased to400 km/h,the response value of various dynamic indicators of the train is significantly higher than that at 350 km/h,and the safety and comfort of the train are both reduced.The safety of the train can still be guaranteed,but the ride comfort is poor,and there are certain hidden dangers of comfort.Its adaptability needs to be further improved.If possible,the size of the radius of the circular curve and the length of the straight line can be appropriately increased,To ensure the safety and comfort of passengers.