Konferensartikel

The train service scheme of an urban rail transit line specifies information such as the total number of train services operated in the line, and the associated turn-back stations, train size and frequency of each service. A reasonable train service scheme can provide satisfactory services for passengers and reduce the operational cost for operators. This paper focuses on the optimal train service design problem in an urban transit line, where both the short-turn services and the train size of each service are considered. A service network based on a given pool of candidate train services with provided turn-back stations is constructed. The optimal strategy is used to assign passenger flows on the service network so as to describe the service choice behaviour of passengers between different train services. Considering many operational and capacity constraints, a mixed integer nonlinear programming model minimizing the sum of the operators’ cost and passengers’ waiting time cost is developed to identify train services from the service pool and determine the train size and frequency of each chosen service. The nonlinear model is transformed into a linear one, and two simplification methods named service network simplification and OD pair aggregation are proposed to improve further the computational efficiency of the model. Finally, realistic instances from Chongqing Rapid Rail Transit Line 26 in China are used to test the proposed approaches. The results show that our approach can effectively reduce the operators’ cost and the passengers’ waiting time cost compared with the empirical method frequently used in practice.

Urban rail transit, train service design, short-turn service, train size, service network, optimal strategy