Lane-based analysis of the saturation flow rate considering traffic composition

ABSTRACT Saturation flow rate (SFR) is an essential metric for estimating the capacities of signalized intersections. Many factors, including traffic composition, configuration and geometry of the intersection, and driver behavior, which is typically characterized by social and cultural norms, influence SFR. Most of the previous studies estimated the SFR and adjustment factor to be applied independently without considering the interaction impact between influencing factors. This study aims to empirically examine the influence of the number of lanes, the heavy vehicle proportions, and their interaction effect on the SFR of through movements. A new model was developed to magnify the HV Impact on SFR value considering the number of lanes at the upstream approach. The outcome of this study helps to improve the multiplicative model’s structure for SFRs adjustment factors. Adopting the outcome of this study by the responsible transport authority would optimize the road infrastructure provision.