Research On Dynamic Response Law Of Railway Train With Passenger And Freight Railway In Speed Increase

With the continuous opening of passenger dedicated line railway,the transport capacity of existing passenger and freight co-line railway has been released,and the corresponding speed-up of passenger and freight trains on existing lines has become possible.However,the low design standards of existing lines,especially the large number of small radius curves,limit the speed increase range of existing trains,and the existing problems of mixed passenger and freight running on existing lines and large speed difference between trains make it necessary to study the adaptability of speed increase on existing lines.In this paper,the relevant dynamic software is used to model passenger and freight cars respectively,and the influence of the change of horizontal and vertical section parameters on the dynamic characteristics of the train is studied.Especially,the multi-vehicle marshalling model with 25 t axle load is constructed in accordance with the "Code for Design of Heavy-haul Railway" and the relevant speed-up analysis is carried out.The research work carried out in this paper mainly includes:(1)Establishment of Dynamic Simulation Analysis Model for Railway-Line System with Speed IncreaseBased on the vibration equation of passenger car system and the longitudinal dynamic equation of train,using the characteristics of SIMPACK and UM,the dynamic simulation models of plane curve section and freight car are established respectively;(2)Dynamic Response Analysis of Plane Curve Section of Single Train Model and Multi-body Train ModelAccording to the simulation results,the dynamic characteristics of plane curve segments of different models are analyzed.The changing trend of dynamic performance indexes under the conditions of changing parameters such as running speed,radius of plane curve,curve superelevation and length of transition curve is analyzed.A better matching mode of parameters is sought,which provides a theoretical basis for speed-up transformation of Railway lines;(3)Adaptation Analysis of Speed Increase in Existing Small Radius Curve GroupsTaking a small radius curve group section of the existing Longhai Railway as an example,taking the lateral acceleration of the car body,derailment coefficient,wheel load reduction rate and wheel axle lateral force as indicators,the V-S simulation calculation of the line operation is carried out,and the comprehensive analysis is made from the change of the line plane structure parameters to find the optimal speed-raising effect and its matching line shape;(4)Analysis of the influence of longitudinal parameters on the longitudinal dynamic response of freight trainsThe effects of longitudinal parameters on the longitudinal dynamic response of freight trains are analyzed under emergency braking conditions and common braking rotation mitigation conditions respectively.It mainly includes the form of gradient,gradient difference,algebraic difference of gradient difference and the influence of vertical curve on the longitudinal dynamic response of train,and finds out the most disadvantageous position and corresponding dynamic index when the gradient is changed.