Development of Saturation Flow Model at Signalized Intersection for Heterogeneous Traffic

Saturation flow is a very important road traffic performance measure of the maximum rate of flow of traffic. It is used extensively in signalized intersection control and design. Saturation flow describes the number of passenger car units (PCU) in a dense flow of traffic for a specific intersection lane group. The design, the capacity and operation of a signalized intersection critically depend on and passenger car unit (PCU) and saturation flow. In India the traffic is composed of highly heterogeneous mix of vehicles and subsequently drivers don't follow any lane discipline. The intersections on urban roads in India cater to slow-moving traffic including pedestrians. To calculate the capacity we need to know about the saturation flow which further helps to time the traffic signals. However, it is revealed that traditional methods which are mainly developed using the average value of observed queue discharge headways to estimate the saturation headway might lead to underestimate saturation flow rate. In this research paper, the effort was made to analyze the results by developing the dynamic PCU for the candidate signalized intersections catering to mixed traffic condition in Indian cities. In this study methodology was developed to calculate the PCU and saturation flow in accordance for the enumerated traffic conditions. (C) 2017 The Authors. Published by Elsevier B.V.