New Low Noise Pavement Surfaces by the use of Crumb Rubber

The principal advantage of introducing some percentages of crumb rubber in production of asphalt mixtures is related to pavement environmental sustainability, since this process allows to recycle a significant amount of an industrial waste; there are some other advantages related to this process that are the improvement of asphalt mixture mechanical properties and durability as well as friction on pavement surface. These new low noise pavement (LNP) surfaces are realized by using the warm mix asphalt (WMA) technology that allows a significant reduction of mixing and compaction temperatures of asphalt concretes. The benefits of using WMA technology may include reduced fuel usage and pollution, and improved working conditions. This paper presents key findings of the Phase I of the Life NEREiDE project. The project has the aim of evaluating the advantages of using crumb rubber in construction of LNP surfaces, specifically designed to reduce rolling noise by optimizing surface texture, by using both the wet and the dry processes. In the Phase I of the NEREiDE project were compared the mechanical and functional performances of the new LNP surfaces obtained by using the two technologies in order to assess their respective potentials for use as viable alternatives to other traditional LNP surfaces aimed to improve pavement sustainability by reducing environmental, social and economic impacts. Results of laboratory and on site tests, carried out on a specifically built field trial, clearly show that these new LNP surfaces can have optimal mechanical and functional performance in comparison to results obtained with traditional LNP surfaces.