Research on the Influence of Different Green Tail Signal Switching Patterns on Traffic Safety at Intersections

摘要

In this paper, we focus on two common green tail signal switching modes in China including: green signal countdown, and flashing green light. And we study the corresponding impact on traffic safety, which is based on vehicle speed, acceleration, overspeed ratio, and red light ratio as the primary criteria. The index value under different green tail signal switching patterns is obtained from live observations and record videos. Software "George" is used for extracting vehicle running data from recorded videos. After comparing and analyzing the index values, the results indicate that the vehicle speed and acceleration is more dispersed and the overspeed ratio, the red light ratio is higher under the mode of green signal countdown with respect to the mode of flashing green. Finally, for the safety, we suggest to cancel the green signal countdown or to install video surveillance and vehicle speed detection device at countdown signalized intersections.