Determining the performance of quieter road surfaces Available to Purchase

Type approval for proprietary thin asphaltic surfacings has recently been introduced in the UK through the Highway Authorities Products Approval Scheme (HAPAS). This scheme includes a noise test that gives a noise classification that can be used for comparing different surfacings. The data generated can also be used to predict traffic noise levels. The assessment of noise is currently carried out using the Statistical Pass-By (SPB) test method. This method has proved to be a suitable interim procedure for type approval purposes but it is currently limited by the stringent site requirements of the standard and by the influence of factors related to the traffic stream and weather conditions. Supplementary test methods are under development that will overcome the site selection difficulties and research has been concluded that will help to take account of influential factors. This paper reviews the progress made in developing suitable test procedures for road surface noise evaluation. It also describes some of the equipment developed in the UK for use in both research and routine assessment of road surface noise.