Research On Influence Parameters On The Vibration Response Of Track Under Railway Polygon Wheels

With the constantly increasing speed of the train,the interaction between wheels and rail is increasing,and the problem of polygon wheel becomes increasingly highlighted.The vibration of the various layers of the track structure caused by polygon wheel becomes prominent.It not only endangers the traffic safety but also causes damage to the vehicle track components.At present,scholars have done a lot of research on the development mechanism of wheel polygons and their effects on vehicle safety and stability.However,there are few reports on the vibration response of track structure and its influence parameters under wheel polygon.This has to be studied further.Based on this,by establishing a rigid-flexible coupling dynamics model of the vehicle track system and the dynamic finite element models of ballasted / ballastless track on subgrade,the effects of track structure parameters on the vibration response characteristics of the track structure under wheel polygons are studied,which will provide theoretical guidance for track structure parameter design and polygon wheel trackside monitoring method.The main research work includes:(1)Establishment of a rigid-flexible coupling dynamics model of the vehicle track system.A rigid-flexible coupling dynamics model of the vehicle track system and the dynamic finite element models of ballasted / ballastless track on subgrade were built by using Universal Mechanism and ANSYS software.These models are used to study the vibration response of the track structure caused by the wheel polygon and its influence parameters.Through comparison and analysis with other literature results,the reliability of the established model is verified.(2)Research on parameters affecting ballasted track vibration characteristics under polygon wheel.The rigid-flexible coupling dynamics model of the vehicle track is used to solve the wheel-rail force caused by the polygon wheel.And it is applied to the dynamic finite element models of ballasted track on subgrade to study the parameters affecting the ballasted track vibration characteristics under polygonwheel,including the vertical stiffness of the fastener,the vertical damping of the fastener,the elastic modulus of the sleeper,the elastic modulus of the track bed,the elastic modulus of the ballast,and the elastic modulus of surface layer of subgrade.(3)Research on parameters affecting ballastless track vibration characteristics under polygon wheel.The rigid-flexible coupling dynamics model of the vehicle track is used to solve the wheel-rail force caused by the polygon wheel.And it is applied to the dynamic finite element models of ballastless track on subgrade to study the parameters affecting the ballastless track vibration characteristics under polygon wheel,including the vertical stiffness of the fastener,the vertical damping of the fastener,the elastic modulus of the railplate,the elastic modulus of the CA layer,and the elastic modulus of the support layer.