New- Guidelines for exposed aggregate surfaces in the netherlands

Today’s opinion on environmental aspects, such as CO2 reduction, does more often lead to the choice of concrete pavements as far as the noise reduction will be solved. On the one hand the ever higher axle loads do ask for rigid pavements, but on the other hand noise also is an environmental aspect especially in built-up areas. Traffic noise, which is in fact the sum of tyre/road and engine noise, is one of the major disturbances for inhabitants. This has resulted into strict legislation with respect to maximum allowable noise levels at the facades of houses. Reducing traffic noise at the source by minimizing tyre/road noise can be achieved by advanced pavement engineering. In the past, many exposed aggregate concrete surfaces have been realised. This started with concrete with a higher amount of fine aggregates in the surface to special designs with a uniform fine aggregate size. But all these pavements in The Netherlands showed up till about 2008 poor till just acceptable noise emissions. In these cases a poorly textured surface caused these disappointing results. The paper deals with the process of the noise reduction of a concrete pavement and will result in the main topics of the Dutch guidelines. An important but often underexposed part of the process “The quality Control” of the exposed aggregate surface during the brushing process is also included.