The Signal Timing of Right Turn Traffic Light at Urban Road Intersections

Abstract

In order to protect the safety of pedestrians and nonmotorized vehicles crossing the intersection, sometimes a right turn traffic light has to be set in the road intersection. Regarding a road intersection with the right turn traffic light, in order to make a trade-off between the safety of pedestrians and the reduction of right-turn movement delay, the key issue is the signal timing of red light for right-turn. Based on the characteristic of pedestrians or nonmotorized vehicles passing through the intersection, this paper analyzes several factors' influence on signal timing for right turn traffic light, including pedestrian crossing time, pedestrian crossing speed, pedestrian queuing evacuation time, nonmotorized vehicle crossing time, nonmotorized vehicle crossing speed, nonmotorized vehicle queuing evacuation time, the volumes of pedestrians and nonmotorized vehicles and the traffic volume gap between peak period and non-peak period, and so on. The authors then establish a formula of signal time setting for right turn traffic light. Finally, it is pointed out that right turn traffic light should be adjusted dynamically according to real-time traffic condition.