Analysis Of A New Combined Rail Yard At A Heavy Haul Railway Combined Station Using Simulation

The combined station of heavy haul railway is generally located in the juncture of joining the interconnection of heavy haul railway and other railway, which is used to combine and decompose the combined heavy-load trains. So the combining and decomposing capacity of a combined station plays a direct and important role in carrying capacity, smooth operation of the collection and distribution system and the utilization coefficient of carrying capacity in heavy haul railway. The research of a new type of combined rail yard at a heavy haul railway station can improve the combining capacity, enhance the collection and distribution system and balance the combining capacity at station and carrying capacity in the block section. In addition, the application of the new combined rail yard also has significant economic benefits. Therefore, the study of new type of combined rail yard has significane in both efficiency and economy.This paper analyzes the combined yard layout form in existing combined station, and introduces the combined heavy-load train’s marshalling modes and connecting processes. By analyzing the advantages and disadvantages of the exiting combined yard, it puts forward a new idea that using parallelogram yards as combined yards in combined station at a heavy haul railway. Then, it elaborates the layout form of grouping parallelogram yard and connecting parallelogram yard and the conbining processes of combined heavy-load trains in them. After that, it puts forward two key algorithms of utilization of arrival and departure tracks.It is difficult for analytical calculation method to accurately calculate the combining capacity of parallelogram yard, but it can be calculated by simulative calculation method. Firstly, the paper introduces the discrete event dynamic system concepts and the development of rail traffic simulation software. And then based on AnyLogic simulation software, it analyzes the system levels, function and subsystems classification in the parallelogram combined yard simulation system, and describes the key algorithms and mechanism in this simulation system. Finally, this paper develops a parallelogram combined yard simulation system.Finally, this paper constructs three combined yard simulation systems:the exsiting traditional yard A, the grouping parallelogram combined yard B and the connecting parallelogram combined yard C. All of them have the same number of tracks. Yard A has 8 combining, receiving and dispatching tracks and 4 locomotive running lines. Each yard has 12 combining, receiving and dispatching tracks in both of yard B and yard C, but no locomotive running lines.Analyses are conducted using the simulation system for different conditions including different directions (single-direction, bi-directions) and different combining tracks. The maximum combined capacity is solved by adjusting the density of trains entered the combining yard. Through simulation analysis, the combined capacity of Yards A, B, and C are 69,85, and 100 trains per day respectively. Compared with yard A, increase of 23% and 45% in the combined capacity are respectively observed for Yards B and C. Above all, the grouping parallelogram combined yard and the connecting parallelogram combined yard have higher combined capacity than traditional combined yard.