Low Noise Pavements in Germany: Established Concepts and New Ideas

Traffic noise, and road traffic noise in particular, is a problem to be solved in densely populated regions worldwide. Tire-road noise is the main source for road traffic noise and low-noise road surfaces are an effective measure for its reduction. In Germany, most low-noise surfaces are built in asphalt, giving a good acoustic performance whereas their durability under heavy traffic is not optimal. Concrete, instead, is very durable and ideal for roads under heavy traffic, but there are only a few concepts of low noise concrete road types. In several research projects a number of low-noise concrete road surface concepts have been investigated, including the optimization of standard road surfaces like exposed aggregate concrete or the postprocessing of concrete roads by diamond grinding. In addition, several new surface types have been developed from a virtual design, taking into account the deeper understanding of tire-road noise generation: these concepts include specifically designed road surface textures, novel materials for road construction such as ultra-high performance concrete or specially designed porous materials. The paper resumes the well-established low noise road surface concepts used in Germany and the outcomes of the above-mentioned research projects.