This study was designed to validate simulator-study results concerning driving speeds with three different delineator post configurations based on post frequency. The distance between delineator posts was 25-50 m on curves and 50-100 m on straight road segments; in one configuration there were no delineator posts on the straight segments. The test configurations were each installed on a specific road segment for about 2 weeks. During this time speed and lateral position of passing vehicles were measured at several sites along the road. Acceptance of these three delineator post configurations was examined in the lab by asking volunteers to compare nighttime pictures. Nighttime spot speed with delineator posts was on average 0.5 km/h lower than before delineator post installation. Nighttime speed differences between delineator post configurations were small. One of the three configurations produced approx-imately 1 km/h higher average speed than the other two, regardless of the road curve radius at the measurement point. The results differed significantly from those obtained with the simulator: in the latter, delineator posts significantly increased the speed, and the speed differences between delineator post configurations were also substantial. We found no statistically significant and consistent relationship between delineator post density and lateral positioning of vehicles. In the acceptance study, the volunteers expressed a preference for high delineator post density.
|Place of Publication||Espoo|
|Publisher||VTT Technical Research Centre of Finland|
|Number of pages||70|
|Publication status||Published - 2013|
|MoE publication type||Not Eligible|
- visual conditions
Rajamäki, R., Luoma, J., & Rämä, P. (2013). Effects of delineator post density on vehicle speed, lateral position and driver acceptance. VTT Technical Research Centre of Finland. VTT Technology, No. 132