Study On The Ruling Grade Standart Of Heavy Haul Railway Based On Dynamics Analysis

Since the21st century, characterized as "high speed passenger transport and freight transport, China’s railway is entering into a new period.The operation of heavy haul train is an important way to promote China’s railway transport capacity. With the development of modern railway, the traditional transport system has encountered many problems, especially in safety and comfort. Due to the increase of train axle load, the heavy haul railway has a damaging impact on railway line and demands a larger longitudinal force when transforming the working states. Thus the improvements of railway alignment and profile play an important role in the transformation of heavy haul transportation line and adapting to the increase of train axle load, which can guarantee the safety of trains, improve the railway line capacity and driving safety.Ruling grade, one of technical designing standards of railway vertical section, has vital influence on railway project economy, train running state, running stability and so on. The choice of ruling grade is related to the whole work of railway. This paper analyzes the effecting factors of ruling grade, how to choose the appropriate ruling grade by calculation. Based on the analysis of force on the whole vehicle model and that on a single vehicle model, under the circumstance of different transforming states, use train-line longitudinal dynamics analysis software for the simulation to research the ruling grade effects on the train running state and stability.In this paper, through the simulation analysis, a conclusion can be made that in ruling grade section and maximum slope gradient section, the maximum towing coupler force of emergency braking is higher than that of transaction condition. Under the circumstance of emergency braking, it can be ensured that the maximum coupler force is within the allowable range by adopting reasonable mitigation initial velocity. According to the results of this analysis, suggestions are given as some certain theories basis and the reference for heavy haul railway dynamic location.