The influence of motorcycle behavior on saturation flow rate at signalized intersections with and without exclusive stopping space for motorcycle (ESSM)

Traffic in most developing nations is considered mixed or heterogeneous. Motorcycle and other vehicle's behavior at signalized intersections would not probably have a similar influence on intersection capacity and time of the traffic signals. In theory, the saturation flow rate is a basic parameter to estimate the intersection capacity and time of the traffic signals. This study, therefore, aims to analyze the influence of motorcycle behavior on the saturation flow rate at signalized intersections in Denpasar, Bali. Traffic flow data are observed at four signalized intersection approaches that have similar width and traffic characteristics. Two approaches have exclusive stopping space for motorcycles (ESSM) while the other two do not. The study results show that more than 50% of motorcycles tend to be distributed beside flow at signalized intersections with ESSM on either light or dense traffic flows. In contrast, at the signalized intersections without ESSM, motorcycles are found to be distributed inside flow during low traffic conditions, while distributed beside flow during dense traffic flow. Besides, the saturation flow rates of motorcycle inside flow are less than that of beside flow at signalized intersections both with and without ESSM. A new method to estimate saturation flow is proposed.