Empirical Observations and Formulations of Tri-Class Traffic Flow Properties for Design of Traffic Signals

摘要

Recognizing the popularity of scooters and buses in many developing countries and the significant impact of their physical maneuverability on the properties of mixed traffic flows, this study presents our findings from empirical observations of tri-class traffic flows, including the complex interactions among scooters, passenger cars, and buses from their discharging to the formation of stop queues at downstream intersections. Using camcorders mounted either on high-rise structures or drones, our empirical data include individual vehicles and their trajectories over time. Formulations based on empirical findings have also been proposed to model the behaviors of such tri-class flows on queue discharging, formation, lane choice in propagation, and filtering processes. Evaluations of field data, with respect to time-varying throughputs, queue clearance times, and queue length evolution, confirms the effectiveness of the proposed formulations. These can serve as the basis for developing mesoscopic tri-class flow simulation models or for designing signals for arterials plagued by such mixed flows.