Optimization Of Wagon-flow Allocation In Marshalling Station Under Classification Track Assignment

Wagon-flow allocation plan in marshalling station is the core of stage plan for railway station.The quality of marshalling decides the efficiency of operational system in railway station.As the mobile device providing driving force for wagon-flow,the shunting locomotive is the key to transportation organization in marshalling station.However,the current researches on marshalling plan largely focus on the tasks and the regulations of operational time.The insufficient foreseeability of station dispatcher for locomotive's operation state and for the mobile path of within-station wagon-flow is the main cause of low delivery rate of the stage plan.As an important part of marshalling station,classification track is the bridge of connecting break-up system and marshalling system.The confirmation of operation state of classification track within the stage plan enables us to know,under wagon-flow coupling scheme,the specific location of multi-unit as well as to help with performance feedback and scheming the operation plan of the shunting locomotive.Therefore,the optimization of wagon-flow allocation in marshalling station taking classification track assignment into consideration possesses its theoretical value and practical significance as well as improves the feasibility of station operation plan,conducts station's overall function and coordinates sub-systems.This paper summarizes current researches on organizational plan in marshalling station and classification track application;then it proposes that the latter is one of the key elements of coordination among the operations of arrival,break-up,marshalling and departure,which is also the starting point and technological route of this paper.Second,this paper analyzes current systematic operation in marshalling station with its inside and outside influence;confirms content of marshalling plan and materials that follows,emphasizes the importance of shunting locomotive operation in stage plan and explains the operation rules of shunting locomotive and classification track.In the goal of better integrating stage plan and actual shunting locomotive operation,applying classification track to the optimization of wagon-flow allocation in marshalling station ensures scientific arrangement of shunting locomotive operation as well as the coherence and completeness of station plan.Third,the minimum time of train staying at the station and the minimum time of coupling for departure trains are set as targets,the model of comprehensive optimization of wagon-flow allocation in marshaling station under classification track is built,fully considering constraints of the capability of facility in the station,marshalling content and train connection time.After the analysis of the model and the actual decision procedure of marshalling,this paper applies Lexicographic method to divide the main task into two sub-problems which are wagon-flow calculation and classification track application.Then,the LINGO software is used to acquire wagon-flow coupling scheme within stage plan and the corresponding shunting locomotive operation plan,fully controlling the conditions of each yard and wagon-flow as well as shunting locomotive state,realizing functional connection of each sub-system and production cooperation.Finally,taking downward of Nanxiang marshalling station as an example,this paper tests on the mentioned model and its solving method;then,draws up an optimized station operation plan which could provide reference for on-site marshalling operation.Additionally,if needed,there is room for station dispatcher to set and adjust the multi-unit classification in wagon-flow calculation scheme as well as the match between train departing and classification track so that the experience and intelligence of station dispatcher is surely considered in computer optimization process thus to improve the overall operational efficiency of marshalling station system.