Research On Coordinated Optimization Of Wagon-flow Allocation For Two Marshalling Stations In Railway Terminal

With the improvement of people’s living standards and the rapid development of the logistics industry,the demand for transportation in the society is increasing day by day,and the competition among various transportation methods is intensifying.Railway transportation accounts for a relatively large proportion of medium and long distance transportation.When railway transportation exerts its comparative advantages,it should pay more attention to the improvement of timeliness and the level of transportation organization,so as to improve its transportation capacity and realize the improvement of competitiveness.Marshalling station is a node of the railway network and an important primary production unit of railway transportation.Improving the transportation organization level of marshalling station is conducive to the improvement of railway transportation capacity and efficiency.The operations among marshalling stations in railway hub are not separated from each other,but connected with each other.Therefore,this article starts from the perspective of collaborative optimization of two marshalling stations in the hub,and studies the problem of coordination and optimization of wagon-flow allocation,which provides theoretical reference for subsequent research on optimization of wagon-flow distribution in marshalling stations.Firstly,this article summarizes the functions,the classification under various standards and the main operations of the marshalling station.Clarified the preparation process,the target and content,and the sub-issues of the stage plan of the marshalling station.The essence,influencing factors and characteristics of distribution are analyzed.Based on the analysis of marshalling stations and the wagon-flow allocation problems of stage plans,the connotation mechanism of the collaborative wagon-flow allocation among marshalling stations in the hub is further studied,including the necessity,feasibility,influencing factors and strategies of the collaborative wagon-flow allocation.Secondly,according to the specific meaning of joint flow allocation,a coordination and optimization model of static wagon-flow allocation for double marshalling stations in the hub is constructed.The optimization goal of the model is to minimize the total cost of wagon-flow allocation of two marshalling stations in the hub,maximize the number of full-axle trains in the two marshalling stations in the hub,and minimize the total time of vehicles staying in the two marshalling stations in the hub.The ideal point algorithm is used to solve the model,and the static wagon-flow combined allocation scheme is obtained.Thirdly,on the basis of static wagon-flow combined allocation,a coordination and optimization model of dynamic wagon-flow allocation for double marshalling stations in the hub is constructed.The optimization goal of the model is to minimize the total cost of wagonflow allocation of two marshalling stations in the hub,maximize the number of full-axle trains in the two marshalling stations in the hub,and minimize the total time of vehicles staying in the two marshalling stations in the hub.The model is solved by the combination of the local area sub-problem optimization algorithm and the ideal point algorithm,and the dynamic wagon-flow combined allocation scheme is calculated.Finally,combined with the calculation examples,the static wagon-flow combined allocation scheme and the dynamic wagon-flow combined allocation scheme are obtained.Compare the static wagon-flow combined allocation scheme with the individual allocation results of two marshalling stations in the hub,and then compare the dynamic wagon-flow combined allocation scheme with the static wagon-flow combined allocation scheme.The rationality of the method of static wagon-flow allocation coordination optimization and dynamic wagon-flow allocation coordination optimization of double marshalling stations in the hub is verified.This article focuses on the related issues of marshalling station wagon-flow allocation optimization,combined with the current development trend of railway freight,and adopts a gradual and in-depth research idea.Clarify the importance of coordinating wagon-flows between marshalling stations in the hub.Construct a static wagon-flow allocation coordination optimization model and a dynamic wagon-flow allocation coordination optimization model for the double marshalling stations in the hub.Realize the purpose of improving the level and efficiency of the operation organization of the marshalling station.The research results can provide reference for the follow-up research on the optimization of wagon-flow allocation in the marshalling station of railway junction.