Research On The Maximum Slope Of Heavy Haul Railway With Heavy Axle Load

With the economic development,the transportation capability of heavy haul railway cannot meet the actual needs of increasing transport demands,so it has been urgent to improve the rate of supply and demand.The most effective way to improve transport capacity is to increase the axle load and the train marshalling.The maximum slope is one of the main technical standards of heavy haul railway,of which the size has a great influence on the safety and smoothness of the heavy haul railway operation.Therefore,based on the theory of longitudinal dynamics,this paper establishes the longitudinal dynamic simulation model of heavy haul railway,and analyzes the maximum slope values of longitudinal sections of heavy haul railway lines which are suitable for 30t axle load and long freight trains from the perspective of dynamics.The main work and conclusions are as follows:(1)Based on the traditional analysis method,the maximum slope of the 30t axle load heavy haul railway line is calculated and analyzed,and the starting conditions,the effective length of arrival and departure track and the coupler strength are checked.Suggestions on maximum slope initial value of light locomotive,double locomotive and three locomotive traction are put forward.The result shows that:When the traction quality is 10000 t,the maximum slope value of the heavy haul railway line can be taken as 4‰ under the condition of light locomotive,10‰ under the condition of double locomotive and 15‰ under the condition of three locomotives.When the traction quality is 20000 t,the value can be taken as 4‰ under the condition of double locomotive and 7‰ under the condition of three locomotives.When the traction quality is 30000 t,the value can be taken as 4‰ under the condition of three locomotives.(2)Based on the longitudinal dynamics theory of trains,the longitudinal dynamic analysis model of long and big heavy haul trains is established by using UM simulation software.In view of the calculated maximum slope of railway line in Chapter 2,the longitudinal dynamic characteristics of the 30t axle heavy haul trains are calculated and analyzed in the conditions of light,double and three locomotive traction and under the working conditions of the uphill traction,downhill emergency braking and commonly used brake release.The result shows that:the proposed maximum slope value of railway line can meet the safety and stability requirements of the operation of long and big heavy haul train.(3)Based on the principle of kinetic energy uphill,adopting the method of the minimum speed method of train,the marshalling uses three HXD2F locomotives to draw 250 C96 trucks in the form of 1 + 1 + 1,and analyze the maximum slope of the line.The result shows that:When the slope length is constant,the higher the uphill speed,the larger the maximum slope value of the line.When the uphill speed is constant,the longer the slope length,the smaller the maximum slope value of the line.When uphill speed is not less than 75km/h at the slope section of which the length is 1000m,the maximum slope ratio can be used 10‰.