Evaluation of the Visibility of Pavement Markings in Wet-Night Rainy Conditions and the Appropriateness of Associated Measurement Techniques

摘要

Researchers evaluated the performance of 18 different pavement markings in a wet-night condition to obtain a better understanding of how a wide range of markings perform under such conditions and how their performance can be assessed. Three metrics were obtained and analyzed: 1) retroreflectivity measurements, 2) dynamic detection distance measurements, and 3) luminance measurements. The retroreflectivity measurements were made under a variety of conditions including dry, wet recovery, and 12 levels of continuous wetting ranging from 0.28 inches per hour to over 20 inches per hour. Detection distance measurements were made in a dynamic setting in which 30 research participants drove through a rain tunnel that was calibrated to produce rainfall rates of 0.28 and 0.87 inches per hour. Finally, the luminance of the markings was measured at 30-meter geometry under the same rainfall conditions as the detection distance measurements. The relationships between the measured detection distances, retroreflectivity levels, and luminance levels were then explored. The results indicate the weakness of ASTM E2176 and provide recommendations for further study.