Aspects concerning the physical-mechanical characteristics of low-noise asphalt mixture

Abstract As the traffic increases in urban areas, the noise generated by the vehicles has become a major concern during the last decade and many countries have been looking for solutions to reduce the level of disturbance. The lowering of the noise level by choosing the correct type of asphalt mixture may be considered as an alternative to sound-absorbing walls. The use of these low-noise asphalt mixtures requires a previous verification of the technical conditions and the performance levels they need to meet. The paper presents the research and laboratory tests aimed at comparing the physical-mechanical characteristics of a maximum 16mm grain size bituminous concrete (BA16) with a low-noise bituminous concrete used in the wearing course of bituminous pavements. This research started from the fact that the Romanian design standard for asphalt mixtures does not stipulate the physical-mechanical characteristics required by a low-noise asphalt mixture. Thus, in order to clarify this matter, the physical-mechanical characteristics of a 16mm grain size laboratory-made bituminous concrete (BA16) were compared to the characteristics of a low-noise asphalt mixture presented by the specialized literature. The results obtained following laboratory testing of the asphalt concrete and the research of the specialized literature concerning low-noise asphalt mixtures confirm the differences as far as their physical-mechanical characteristics are concerned (voids, bulk density, dry density, Marshall stability and flow and stiffness modulus).