The global experience in using low-noise road surfaces : A benchmark report

This report provides a rather comprehensive state-of-the-art review with regard to the global experience of low noise road surfaces, but with the following focus areas: Experience in primarily USA, Japan, the Netherlands, Sweden, Denmark and UK; secondarily in Germany, Austria and Switzerland Relevant parts of large European research projects Experience related to low-speed roads (50 km/h or less) in urban areas The information has also been collected and evaluated with the Hong Kong low noise road surface policy and its assumed future needs in mind. Apart from review of research on low noise road surfaces, country by country, this report also includes a brief review of the particular policies in the mentioned countries with respect to selection of road surfaces and especially coupl ed to the impact on noise emission that this policy has. Naturally, since one of the major noise-reducing tools that the road engineer has is to give the road surface a high air voids content, this review to a large extent deals with porous surfaces. Nevertheless, since in later years so-called thin layers have become very popular, not the least due to low-noise properties, this type of surface is also the subject of large parts of this report. Based on the collected material and evaluation of its results, the author gives recommendations for implementation of certain findings in the Hong Kong low noise road surface policy, as well as suggests topics for further studies and development for the purpose of improving the same