2013 Session: AHD55

• Optimization Design and Experiment on Plane Layout of Edge Line Marking for Speed Reduction
  Abstract: It is known that the installation of edge line marking can help reduce driving speed.Theoretically, higher edge rate density leads to higher perception speed, so as the effect of speed reduction. However, too high edge rate density may result in progressively reduction of overestimating speed even underestimation, due to critical flicker frequency. To further strengthen the application effect of edge line marking, plane layout of double-row and triple-row of edge line marking were proposed from the essence of critical flicker frequency and mechanism of speed reduction of edge line marking. In simulation experiment, different speed perception under different plane layout was measured. The results showed that double-row edge line marking could overcome the restriction of critical flicker frequency and get higher perceived speed. While participants tended to perceive three adjacent edge line markings as a whole when triple-row edge line marking was adopted, which embodied the law of proximity in Gestalt psychology, and then the overestimation of perceived speed had no significant difference with the one when single-row edge line markingwas used.Based on these, road experiments were carried out on the Hangrui highway in China with optimization of single-row and double-row edge line marking. The result showed that the latter performed better with speed reduction. The average speed, 85% speed and standard deviation of speed respectively dropped 9.26km/h, 10.48km/h and 3.0km/h, with separately reducing range of 9.0%, 9.0% and 38.0%, which got better improvement than that using single-row edge line marking.
  Authors: Liu, Bing; Zhu, Shunying; Wang, Hong; Cheng, Lingzi
  Authors: Liu, Bing; Zhu, Shunying; Wang, Hong; Cheng, Lingzi
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Operations and Traffic Management; Safety and Human Factors
  Session: AHD55
  Paper Number: 13-3528
• Assessment of the Durability of Wet Night Visible Pavement Markings: Retroreflectivity Experiment
  Abstract: This paper encompasses the assessment of the retroreflectivity of wet-reflective pavement markings which were recorded as part of a research effort to establish the durability of pavement markings in an on-road installation. Six marking technologies were installed on a portion of Route 460 in Blacksburg, Virginia. A human factors experiment in natural rain conditions was performed to establish the visibility needs of the driver (discussed in a separate paper). The retroreflectivity of the markings was measured at intervals of 2 to 5 months, with six measurements over the course of 23 months. The numbers of snow plow crossings and chemical treatments were also measured.Although all markings lost a considerable amount of retroreflectivity after the first winter, the markings installed in grooves or in rumble strips were shown to retain more retroreflectivity and receive less damage than markings installed on the surface of the roadway. Twenty-three months after installation, the retroreflectivity for all markings in active rain conditions had dropped below the 150 mcd/m2/lx minimum recommended from previous research. The Wet-Reflective Tape was the closest to maintaining the minimum with a mean retroreflectivity of 137 mcd/m2/lx in 1 in/hr rain. Several other markings maintained a retroreflectivity above 84 mcd/m2/lx; this may still provide a benefit over standard paint.
  Authors: Gibbons, Ronald B.; Williams, Brian; Cottrell, Benjamin H.
  Authors: Gibbons, Ronald B.; Williams, Brian; Cottrell, Benjamin H.
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Operations and Traffic Management; Safety and Human Factors
  Session: AHD55
  Paper Number: 13-3799