Study On Stiffness Of Elastic Parts Of Vibration-Reducing Track In High-Speed Railway

It is the trend of the future development of rail transit that high-speed railway enters into big cities and connects with urban rail transit network.According to the construction experience of urban rail transit,the environmental vibration and noise problems caused by high-speed railway must be solved in order to adapt to the development of modern city.It is the general trend that vibration reducing track is used in high-speed railway.At present,graded vibration reduction measures are widely used in urban rail transit,and good vibration control effect has been achieved.However,the application of vibration damping track in high-speed railway is still in the stage of research and test.Based on the theory of vehicle track coupling dynamics,combined with the finite element theory and multi-body dynamics simulation software,this dissertation systematically studies the influence of different types of track vibration reduction measures on the dynamic response evaluation index of vehicle and track system The applicability of typical damping track stiffness values in urban rail transit damping system in high-speed railway is evaluated,and the reasonable value range of damping track stiffness parameters of high-speed railway is proposed.The operating speed of the vehicle has a significant impact on the vibration response of the car body,track and subgrade.The faster the vehicle speed,the greater the vibration response.Therefore,the existing vibration damping track in urban rail transit should be used in high-speed railway applications to adjust the stiffness parameters of the elastic support.Although lowering the support stiffness of the vibration reduction measures can effectively reduce the environmental vibration,it will lead to an increase in the vibration acceleration of the upper structure of the vibration damping layer of the track structure,including increased rail deformation and acceleration.When the three types of typical damping measures used in urban rail transit(damping fasteners,elastic long sleepers,steel spring floating slabs)do not change the stiffness of the damping components,they are directly used for high-speed railways,and the trains are in the speed range of 80～240km/h.During internal operation,under the premise of maintaining the existing track irregularity level,the dynamic response of the vehicle and the track does not exceed the relevant specification limit requirements;compared with the existing track structure of the high-speed railway,the three types of typical damping track have the same effect on the environmental vibration.There are different degrees of reduction effect.When a high-speed train runs at a speed of 200km/h on three types of typical damping tracks,typical fastener damping measures cannot achieve the expected damping effect on environmental vibration while ensuring the stability of the track structure;typical sleeper damping When the support stiffness of the sleeper node is in the range of 15～30k N/mm,it can not only maintain the stability of the track structure,but also has a better environmental vibration suppression effect;typical track bed vibration reduction measures When the support stiffness of the track bed node is in the range of 15～25k N/mm Under the premise of ensuring stable vehicle operation and stable track structure,a better vibration reduction effect than typical sleeper vibration reduction measures can be obtained.