Investigating drivers’ decision zones at high-speed intersections in China based on the acceleration-deceleration diagram

Abstract

The objective of this paper is to empirically investigate drivers’ decision zones at the onset of flashing green and yellow indication at rural high-speed intersections in China. 1122 high-resolution trajectories of the first-to-stop and the last-to-go vehicles during the phase transition time period were collected at four intersection approaches in Shanghai. Speed-Distance (S-D) diagram and Acceleration-Deceleration (A-D) diagram were then used to analyze the distribution of drivers’ decision zones in response to the onset of flashing green and yellow respectively. The former is a conventional approach based on a fundamental assumption that no drivers would accelerate to cross or make an abrupt stop. The latter is a more flexible method based on the required acceleration rate to cross and the required deceleration rate to stop which can be extracted from vehicle trajectory data. Results support that the installation of flashing green helps to reduce the dilemma zone according to the A-D diagram. There are limits when using S-D diagram to analyse the driving situations based on G.H.M model.