Modeling Capacity and Delay Based on Bus Bay Blockage and the Influence of Traffic Flow

The determination of capacity and delay significantly affects the transit system’s performance from the perspectives of operators, passengers, and vehicles. Buses will form the spillback queue, in the entrance of the bus bay, when the demand of buses stopping is high. Therefore, bus bay blockage will reduce the capacity and service level of the bus bay and increase the dwell time. The upper partial moment is used to estimate the maximum threshold of blockage probability. The capacity of the bus bay is modeled as a function of arrival buses, blockage probability and critical headway, taking into account spillback and blockage in bus bay entrance and exit. According to bus bay operating time and dwell time, the research aims at estimating a delay based on blockage probability, traffic flow of the adjacent lane and the number of berths. Congestion can be effectively alleviated by increasing the number of berth when demand of buses stopping is low due to the probability threshold has significant change. However, the probability has little significant change when traffic flow of the adjacent lane is more than 450veh/h. It is significant to have congestion delay when multiple bus routes converge into a bus bay.