> measurements of tyre - Road contact noise : Methodology and application to the evaluation of the acoustic performance of road surfacings

Rolling noise, which is the principle source of noise for vehicles travelling at over 60 km/h, is currently measured using the pass-by method described in the French standard S 31-119. This standard lays down procedures for in-situ near field noise measurements in the case of isolated vehicles and four specified vehicle and tyre configurations. The aim of these procedures is to compute the noise level for a given level of traffic, characterize pavements or rate different highway construction technologies. In order to validate the reproducibility and repeatability of these two procedures, parallel studies have been conducted in different laboratories. All the measurements made according to the standard S 31-119 by the Laboratoires des Ponts et Chaussees were then stored in a data base to permit statistical analyses, investigate change in noise levels with the age of the surfacing, or appraise different surfacings from the acoustic point of view.