Development of an acoustically optimized multi-layer surface-system based on synthetics

To facilitate modern economies, the development of society and the extension of economic areas the traffic sector plays a leading role by supplying a technically functioning, efficient and environmentally compatible infrastructure. Due to the increase of transportation processes, especially the commercial transport, the mode of transport “road” is of great importance in this regard. However, this causes a steadily increasing exposure of the population to traffic-induced emissions – especially noise emissions have received more attention in recent years! Public infrastructure construction is subjected to numerous attempts aiming to standardize the tasks as well as the limitation of costs. The result has been that the innovation potential, especially in regard to designs limiting traffic noise, has not been made use of sufficiently. Furthermore, the performance limit of conventional materials has almost been reached which is why this research project developed and designed a completely new surface-material concept based on synthetic materials. The surface-system was designed to exhibit the highest possible acoustically favorable properties, was verified by examinations in the Vehicle-Pavement Interaction Facility of the Federal Highway Research Institute (BASt) and was constructed in-situ. The focus of the project was the development of a multi-layered wearing course system with a synthetic top layer, representing optimized texture-properties and a synthetically-bound bottom layer functioning as an absorption layer. In addition to the acoustic efficacy of such a wearing course system, the structural feasibility as well as the durability of the concept are subjects of the analysis. Over all the concept shows a level difference of tire-road noise of more than 8 dB(A) regardless of the speed – this is almost a half of the perceived volume.The presented results are converted into further development steps to facilitate transfer of the idea into a marketable product. This further development is carried out within the framework of the research project “Fundamental research on polymer materials and innovative production and installation technologies for road surface layer systems (INNO PAVE)” funded by the Federal Ministry of the Education and Research. In addition to the RWTH Aachen University, represented by the Chair and Institute of Highway Engineering Aachen, an interdisciplinary team from science, research and industry is involved in this further development, which will be finalized in 2018. The described work symbolizes the initial basis for this. Keywords: Acoustically optimized road surfaces, Noise reducing coating systems, Synthetic binders, Multi-layer top coat systems, Poro-elastic road surfac