Research on the Delay in Signalized Intersection with Left-turn Special Phase

Firstly, this paper analyses the necessity of setting waiting area for left-turn vehicles, taking scheme of preliminary signal in the intersection, which can be controlled by the left-turn waiting area or preliminary signal. Then, this paper analyses the calculation methods of preliminary signal under different size of intersections, and gives a qualitative research in effective green time. Finally, based on the theoretical analysis, a simulation method is used to verify the decrease of delay and stops, which suggests that the preliminary signal of left-turn reduces the fuel consumption and wasted emissions of environment.