Pavement reflection properties and luminance distribution: measurements on a road lighting test-track and comparison with standard calculations

摘要

For several years, the French network of Public Works Laboratories has been studying the reflective properties of pavement materials in order to assess their impact on road lighting. For this purpose, a portable CIE-compliant goniophotometer has been designed to measure r-tables, and a prototype software has been developed to compute luminance levels and uniformities from digital images grabbed with a calibrated camera. In order to test these tools in operational conditions, an experiment was conducted on a road lighting test track. The reflection properties of the pavement of the track were measured in-situ with the portable goniophotometer, and compared to those measured on surface samples with a fixed-base goniophotometer. Two lighting configurations were tested, in which the luminance distributions were measured with a normal photometer and compared to those measured with a videophotometer. Finally, the luminance distributions were calculated, taking into account the photometric properties of both the pavement and the luminaires, and compared to the measurements.