What you measure is what you get? - a novel approach for specifying and controlling acoustic quality of road surfaces
Tuesday 2 june, 2015, 11:00 - 11:20
0.2 Berlin (90)
Low-noise road surfaces are very effective noise reduction measures for traffic noise. These roads are designed such that road texture and acoustic absorption are optimal for a certain traffic mix. But they should also comply with (civil engineering) boundary conditions such as durability, friction and rolling resistance. The optimal design for a certain road is then often expressed in civil engineering terms like stone mixture, grading curve, layer thickness, and porosity. But knowing the optimal parameters is only half of the story: How to treat deviations from the optimal recipe? Can less porosity be compensated for by a thicker layer? What if we change the granulate supplier? Does the road surface still perform within the limits that are set by the client or the environment? For the reconstruction of the main highway in the Rotterdam harbor area, we were faced with these questions. The road surface for this road was optimized for maximum noise reduction and durability, knowing that there is a significantly larger amount of truck traffic on this road than on any other road in the Netherlands. In a joint effort, the constructor, acoustic consultant and client decided on a new approach to specify and evaluate the acoustic quality. We used parameters that civil engineers can obtain easily and on the same time accurately predict acoustic quality. By taking drill core samples from the road, using absorption measurements and the SPERoN tyre/road noise model, we are able to devise a two parameter characterization (layer thickness and degree of compaction) of the road surface. This characterization is now used by the contractor to demonstrate that the road surface they build complies with the client’s wishes.
ICS file for iCal / Outlook