Optimal Bus Bridging Schedule with Transfer Passenger Demand during Disruptions of Urban Rail Transit

Abstract

To address the transfer connection problem for urban rail transit (URT) and bus bridging in the case of unscheduled operation disruption, an integrated optimization model for bus bridging timetables and vehicle scheduling is proposed that considers the surge characteristics of transfer passenger flows. First, we analyze the transfer connections between the URT system and the bus bridging system and introduce the concept of passenger tolerance to determine whether a connection is maintained. A bilevel programming model is formulated, in which the upper level addresses timetable optimization with the aim of minimizing the passenger waiting time and the number of transfer failures, and the lower level addresses vehicle scheduling with the aim of minimizing bus operation cost. To solve the proposed model, an improved simulated annealing (SA) algorithm is developed. Finally, a case study of the Shanghai Rail Transit Line 10 is analyzed. The results show that, compared with the even headway timetable, the proposed model results in a 13.7% reduction in total cost, a 14.1% reduction in passenger waiting time, and a 54.9% reduction in the number of failed transfers.