Max-Pressure Signal Control with Transit Priority and Lane Blockage Mitigation: Considering Dwelling Buses and Permitted Left Turns

Abstract

Urban traffic congestion remains a critical issue, intensifying with ongoing urbanization and increasing traffic volumes. While “max-pressure” (MP) control has emerged as a robust, decentralized strategy for optimizing intersection signals based on real-time queue dynamics, it traditionally overlooks transit vehicles and real-world complexities such as lane blockages (LB) because of buses dwelling at stops and permitted left-turn movements. This paper introduces an innovative extension of the MP paradigm for right-hand traffic systems, termed “MP-TSP-LB,” which explicitly integrates transit signal priority (TSP) through weighted priority schemes and accounts for LB caused by both dwelling buses and permitted left turns. The proposed approach modifies the conventional MP framework by introducing weight-based prioritization of buses without disrupting overall network stability. Additionally, the model incorporates effective lane capacities by estimating blockage probabilities, applying critical gap acceptance theory for permitted left turns and probabilistic dwell-time distributions for buses. The MP-TSP-LB model was rigorously tested through simulation on a 3 × 3 grid network using the Simulation of Urban Mobility simulation environment. Results indicate that the MP-TSP-LB model significantly enhances network performance across multiple metrics compared with baseline MP formulations. Sensitivity analysis demonstrates that the model reduces total waiting times and increases average travel speeds for both private vehicles and transit across various demand levels. Incorporating permitted left turns effects significantly improves performance under low-to-moderate demand levels, while modeling dwelling bus blockages becomes increasingly effective as transit service frequency intensifies.