Integrated Metro Train Scheduling and Passenger Flow Control Under Oversaturated Conditions

Integrated demand and supply coordination is a critical technique for urban rail transit lines under oversaturated conditions. Focused on a bi-directional urban rail corridor, this study presents an integrated optimization approach for the train scheduling problem (including both train timetabling and rolling stock circulation) and the passenger flow control problem. Flexible train composition that can flexibly determine the number of train cars comprised in each train service is considered to accommodate dynamic passenger demand. A novel mixed-integer linear programming model is developed to minimize the waiting times of all passengers. Specifically, passenger flow control and passenger loading processes at each station, train service headway restrictions and train car circulation operations at each start and terminal station are formulated simultaneously. Numerical results indicate that the severe congestion in some specific stations can be greatly relieved and the transportation capacity is redistributed in a more efficient and balanced way among all stations.