Optimization of noise reducing thin pavement layers in Denmark and the Netherlands

The Danish Road Institute (DRI) and Road and Hydraulic Engineering Institute in the Netherlands (DWW), since 1 October 2007 Centre for Traffic and Navigation, are cooperating on the DRI-DWW Noise Abatement Programme that includes a research project on Thin Pavement Layers. As part of this project full scale tests of different types of noise reducing thin layers are performed in both countries. The objects of this research work is to develop and optimize noise reducing thin pavement layers for motorway application, and document the noise reducing effect, and on a long term the acoustical and the structural lifetime of the thin pavement layers. The work is carried out in the framework of the Dutch Noise Innovation Program for Road Traffic (The IPG programme). In Denmark optimized mixes of thin layers have been developed. In 2006 11 new test sections were constructed on a motorway in Denmark. In the Netherlands different contractors were asked to lay their product on six different motorway locations. The test sections were constructed in summer 2006 and spring 2007. The comprehensive research programme consisted of measurements regarding the following properties: noise (SPB and CPX), skid resistance, braking deceleration, water permeability and texture. The results of the first years of comprehensive measurements will be presented.