Analysis Of Dynamic Characteristics Of Curve Section Of High-speed Railway

The popularization of high speed railway is a major breakthrough in the development of railway in this century.In the process of high-speed train operation,the dynamic response of vehicle to track interaction increases with the increase of the train running speed,especially in the plane curve section,because of the irregularity of railway track itself,the dynamic response of the system is obviously increased.Therefore,the complete analysis of the dynamic response law of the plane curve section of the high speed railway is very important to further improve the safety,comfort and the stability of the track structure.Based on the design specifications of high speed railway lines,the geometric parameters of the lines under different curve radius conditions are set up,and a complete locomotive,line track system space model is set up.According to the random irregularity of 2~200m of the high-speed railway track spectrum in China and the Japanese short wave irregularity with the 0.1 to 2m wave length range,it is used as the excitation source of the system simulation and the construction of the wheel and rail empty.The multi body dynamic simulation software um is used to simulate the model,and the interaction of the car body,wheel rail and the dynamic response of the rail are analyzed in detail under the different plane curve parameters.Through the simulation analysis,we can draw the following conclusions:(1)according to the dynamic response analysis of the system,based on the strict management standards of ballastless track irregularity in China,the ballastless track spectrum in China shows excellent dynamic performance,and meets the plane curve section of the train with 250km/h,300km/h and 350km/h design speed safely and comfortably.When the train passes through the curve section at 400km/h speed,it is found that the dynamic response index of the wheel rail increases greatly and the derailment coefficient is close to 0.8.Thus,it can be seen that if the train running speed is further improved to 400km/h under the existing standard conditions,the operation cost will not only be increased greatly,but also the safety can not be guaranteed.(2)when the train goes to the slow point and the circular point,the maximum value of the safety and stability will appear,and the maximum steady state value occurs when the circular curve runs into the circular curve.It can be seen that the key position that restricts the safety of the train running when the circular slow point and the slow circular point.With the increase of the radius of the circular curve,the derailment coefficient,the wheel load reduction rate,the lateral acceleration of the car body and the lateral force of the wheel and rail are decreasing,but when the radius is more than 9000 m,the trend is no longer obvious.At this time,the train running speed becomes the main factor affecting the dynamic response of the system.(3)for the dynamic frequency response of the car body and track at high speed,the main vibration range of the vertical vibration acceleration of the car body is concentrated in 0.5 to 10 Hz,while the lateral vibration acceleration of the body,the lateral force of the wheel rail and the peak frequency of the derailment coefficient are close,and the main frequency is concentrated in the low frequency vibration of about 1.5Hz;the vertical displacement of the rail and the peak frequency of the load reduction rate of the wheel weight appear.In the range of 40 to 50 Hz.Therefore,to improve the driving quality and the stability of the track structure in the plane curve section of the high speed railway,the low frequency vibration under 10 Hz and the control of the frequency frequency range of 40~50Hz should be strengthened.