I henhold til aftale om en grøn transportpolitik af januar 2009 er der afsat en samlet pulje på 400 mio. kr. frem til 2014 til en målrettet indsats for at reducere problemer med støj fra trafik. Målet med puljen er at nedbringe generne fra trafikstøj langs de overordnede veje og jernbaner. Der er inden for rammerne af puljen afsat 10 mio. kr. i 2009 til udvikling af nye metoder til støjbekæmpelse i perioden 2009-2014. Metoderne vil bidrage til at opfylde målene på støjområdet, herunder at effektivisere støjindsatsen og optimere effekten pr. investeret krone. Formålet med dette projekt om trafikafvikling og støj er at skabe grundlag for at tage hensyn til støjen ved udformning af vejnettets strækninger og kryds. Dette forprojekt skal klarlægge, om der findes en metode der kan optimeres til brug ved fastlæggelse af den støjmæssige betydning af udformningen af kryds og rundkørsler. Rapporten er skrevet af Gilles Pigasse fra Vejdirektoratet – Vejteknisk Institut. Bent Andersen og Hans Bendtsen har kvalitetssikret rapporten

Accelerating vehicles emit more noise than vehicles with constant speed and they are a major source of noise pollution in cities, especially near intersections where the driving pattern of a vehicle is likely to change. It is investigated whether there is a difference in noise emission at selected and significantly different roundabouts and intersections. The two road designs that have been investigated in the present study are the conversion of a crossing into a roundabout (near Snoldelev) and the enlargement of an already existing small roundabout (on Willumsens Vej). In both cases the noise level at two different positions along the road has been predicted using the Nord2000 model before and after the change in their design. It was possible to predict a change in the noise level due to the change in the road layout and the resulting changed traffic conditions. These predictions are supported by in situ noise level measures. The measurements that were carried out in Snoldelev showed a decrease in noise level in the selected positions of up to 3.7dB, and on Willumsens Vej the noise level increased slightly (max. 1 dB). There is a fairly good agreement between the measured and modelled levels, between 0.1 and 2.8 dB differences. Part of this difference can be explained by a different age and type of pavement before and after the reconstruction – rather than caused by the changed road configuration. Suggestions are made to further improve the measurements as well as the prediction methods.