Investigating the Impact of BRTS Priority with Adaptive Traffic Control System on Urban Corridors Using Microsimulation Technique

Indian road traffic is composed of a diverse mix of vehicle classes with varying static and dynamic characteristics, operating under heterogeneous traffic conditions. The continuous rise in the number of vehicles has led to increased congestion, which is the most vital cause of urban air pollution. Traffic congestion and vehicle emissions are strongly interlinked, and the concentration of pollutants is found to be greater at traffic signals due to the influence of signal operation on the speed of vehicles. Moreover, public transit vehicles such as buses occupy more city street space than solo automobiles. Prioritizing the movements of these high occupancy vehicles at signalized intersections helps smoothen the traffic flow is a well-proven policy, thereby reducing the possibility of the development of emission hotspots near traffic signals. Bus priority at signalized intersections, particularly on single-lane approaches, where bus lanes cannot be provided, is a promising step toward optimized transport system performance. In this regard, the use of Adaptive Traffic Control Systems (ATCS) is expected to minimize traffic flow instabilities, resulting in more consistent flow patterns. This research examines the effect of BRTS priority with ATCS on urban corridors via microsimulation in VISSIM 9.0. The effect of a new ATCS algorithm on travel time, delay, and emissions is explored, with exhaust emissions being approximated by EnViVer software. The research compares the performance of BRTS priority with fixed signal control and ATCS for the selected roadway corridor in India. The results indicate that when the fixed signal control offers priority to BRTS buses, it lacks overall system efficiency. However, ATCS ensures balanced prioritization of the BRTS buses and other traffic (vehicles), and also offers better performance in terms of traffic flow improvement and emissions reduction in the traffic state of better driver compliance.