Research On Relevant Problems Of Single-Track Heavy-haul Freight Railroad Capacity

Heavy haul is an important development direction of China railway. Since the1990s, with the experience from abroad, China has carried out a series of heavy-haul freight railway construction and the network of heavy-haul freight railway is taking shape now. Recently, with the development of China economy, the demand of heavy-haul freight is growing rapidly, which challenges the line capacity. Therefore, to evaluate the capacity of existing lines is greatly beneficial both to the line operation and to the capacity allocation in railway network. However, the existing heavy haul freight line is different from conventional rail line in organization because of the difference of technical equipment and transportation task. Especially for the single track railway, the organization is very complicated, which limits the application of calculation methods of railway capacity.Accordingly, from a practical standpoint, the paper studies the specific questions confronted in the capacity calculation of the single-track heavy-haul freight railway.Firstly, through abstracting the operating condition of the existing heavy-haul freight railway, the line conditions and organization of the target line are set and dividing standard of I and II class train is given. The major problems are proposed through analysis of the features of railway capacity.Secondly, the problems proposed are studied respectively.â‘ The paper researches the maximum amount of class II train in the target line. The detailed idea of graphic calculation is determined and the scheduling problem of class II train is studied referring to the ideas of modeling and solution of job shop schedule problem. On that basis, the calculating method of maximum amount of II class train is designed.â‘¡The paper researches the maximum amount of I class train based on a certain scheduling scheme of class II train. Based on the detailed idea of graphic calculation, the schedule optimization problem of class I train is studied. On that basis, the calculating method of maximum amount of I class train based on a certain scheduling scheme of class II train is designed.Finally, by integrating all above studies, the capacity of Dazhun Railway is studied, including:â‘ calculating the maximum amount of10000t train;â‘¡comparing10000t train scheduling schemes.