Effect of Gap Acceptance Behavior of the Right Turning Vehicles on the Major Road Stream for Uncontrolled Three-Legged Intersections under Mixed Traffic Conditions

Uncontrolled intersections are the intersections where there are no external signs or signals to control the movement of vehicles. In mixed traffic conditions priority rules are often violated by the road users. In All-way-stop-controlled intersections (AWSC), the vehicle should stop themselves before they enter the intersection and should check whether any vehicles are present in the other approaches of the intersection. If no vehicle is present, then they can cross the intersection. For this study, data were collected from two uncontrolled three-legged intersections located at various parts of India and critical gap required for each vehicle combination to cross the intersection are extracted. Gap Acceptance method is used for mixed traffic condition because it is based on the critical gap and follow-up time, which in turn depends on the type of vehicles and traffic conditions. This study tries to analyze the effect of vehicle type on gap acceptance behaviour at uncontrolled three-legged intersection. From this study, it is observed that size of the vehicles and traffic volumes has an influence on the critical gap. Depending on the major road vehicle type combinations, the critical gap for each right turning subject vehicle varied from minimum of 1.4 s to a maximum of 8.7s.