Effects of edge rate of the designed line markings on the following time headway

Abstract

Time headway is an important indicator for evaluating car-following safety.To study the inuence of edge rate on time headway in car-following, three patterns ofline marking were designed and placed on a real-world expressway, with actual vehicleow data collected. Statistical analyses showed that (1) Time headways raised after theinstallation of line markings compared with the original situation; and (2) When the valueof edge rate fell in [5 Hz,14 Hz], the time headway rose along the increase in the edge rate.Furthermore, the increases in time headways were interpreted in relation with the levelingup of the drivers' risk perception due to its overestimation in speed and underestimationin distance caused by edge rate. The nding of this study suggests that the designed linemarkings may bene t engineers and decision makers in providing them with a new approachto cope with critical issues in tra c safety.