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

Document Type : Article


1 School of Transportation, Wuhan University of Technology, 1178 Heping Avenue, Wuhan, Hubei 430063, China

2 Planning Research Studio, Department of Transportation of Hubei Province, 428 Jianshe Avenue, Wuhan, Hubei 430030 China.


Time headway is an important indicator for evaluating car-following safety.
To study the in
uence of edge rate on time headway in car-following, three patterns of
line marking were designed and placed on a real-world expressway, with actual vehicle

ow data collected. Statistical analyses showed that (1) Time headways raised after the
installation of line markings compared with the original situation; and (2) When the value
of 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 leveling
up of the drivers' risk perception due to its overestimation in speed and underestimation
in distance caused by edge rate. The nding of this study suggests that the designed line
markings may bene t engineers and decision makers in providing them with a new approach
to cope with critical issues in trac safety.


Main Subjects