A geometric design method for intersections with pre-signal systems using a phase swap sorting strategy

Abstract

Conventional geometric design methods for pre-signal systems usually use the expected traffic demand, which may obtain a short sorting area distance and lead to frequent queue spillbacks due to stochastic traffic arrivals. On the other hand, if one selects a longer sorting area distance, the geometric design will suffer from low spatial utilization with higher delay and lower capacity. In this paper, we propose a geometric design method for intersections with pre-signal systems using a phase swap strategy. The geometric design can balance the desire of storing more vehicles to prevent spillbacks and improve the spatial utilization of the road. We model the traffic dynamic within the pre-signal system using queue theory and shockwave theory to determine the furthest point a queue can reach. The length of the pre-signal system should be short enough to improve spatial utilization but longer than the furthest point of the queue to prevent queue spillback. The effectiveness of the pre-signal system is evaluated by the VISSIM Signal Control Application Programming Interfaces (SCAPI). The results indicate that the proposed design plan increases the spatial utilization of the pre-signal system by 7.5% while maintaining a similar delay, queue length and ratio of flow to saturation flow.

An adaptive timing mechanism for urban traffic pre-signal based on hybrid exploration strategy to improve double deep Q network

“…Zhao et al [15] applied the pre-signal and sorting zone combination to the exit ramp area to eliminate the conflict of traffic flow and increase the overall capacity of the roadway. Li et al [16] proposed a pre-signal intersection geometry design using a phase-switching strategy to select a more appropriate sorting zone distance and improve space utilization. Bie et al [17] applied the pre-signal to signalized intersections, determined the detector location layout, and established a bus signal priority adaptive control algorithm to alleviate the congestion caused by the priority strategy on social vehicles.…”

Intersection control strategy optimization based on exchangeable lanes modeling

“…Another set of methods use main signal and pre-signal to control the direction of dynamic waiting lane periodically. Based on the study of vehicle delay at intersections with dynamic waiting lanes and the constraint relationship between the main signal and the pre-signal, a coordinated control model of the main signal and the pre-signal was established to minimize the waiting lane and average delay (Chen et al , 2018; Li et al , 2019; Zhao et al , 2020). The pre-signal system can make full use of all lane space, which can significantly improve the utilization rate of road space.…”