Impacts of Flashing Green on Dilemma Zone Behavior at High-Speed Intersections: Empirical Study in China

Abstract

AbstractThis study investigated the impacts of flashing green on dilemma zone (DZ) behavior at the high-speed intersections with insufficient yellow interval. 360 high-resolution vehicle trajectories, used in the study, were obtained from an extensive survey at a typical rural high-speed intersection in Shanghai. Results indicate that with the presence of a flashing green signal, the measured behavioral parameters related to DZ determination at the onset of yellow tend to be remarkably smaller. The vast majority of drivers reacted to the onset of flashing green, instead of yellow onset. Flashing green significantly reduced the area of Type I DZ at the onset of yellow, while enlarged the areas of option zone and Type II DZ. Time to stop line at the onset of flashing green positively affected the stopping probability. Flashing green induced conservative stops by 30%, while encouraged aggressive passes slightly.