Providing Priority to Public Transit in the Absence of Dedicated Lanes: An Exploratory Experiment on the Automated Guideway Transit System

Abstract

This paper presents a novel strategy for giving priority to automated guideway transit vehicles (AGTVs) in mixed traffic flow. From the perspective of road segments, a moving-block operation mode (MBOM) was proposed to help AGTVs eliminate the dependence on dedicated lanes. The car-following and lane-changing behaviors of both AGTVs and general vehicles were modeled using the theory of cellular automata. From the perspective of intersections, an MBOM-based dynamic multirequest signal priority (DMSP) model was developed to support the decision of multiple priority requests at the intersection. Notably, the DMSP model can synchronously deal with early green and green extension requests from the same or different phases. Extensive microsimulation experiments were conducted to examine the proposed strategy at various levels of traffic volume and AGTV headway. The results indicated that the MBOM outperforms the traditional strategy of setting up full-time or intermittent dedicated lanes, particularly in traffic conditions where the headway of AGTVs is longer than 300 s and the traffic volume is lower than 9.0 kpcu/h. Furthermore, the MBOM-based DMSP strategy was evaluated in terms of the performance of both traffic and energy efficiency. The per person travel time and coal consumption decreased by 6.93% and 1.61%, respectively, demonstrating the effectiveness of improving operational efficiency and sustainability of public transit.