Bitumen quantity reduction for stone mastic asphalt (SMA) – suitable material for the environment

This paper describes the mix design (recipe) for SMA that consists of aggregate obtained from stone with relatively high specific gravity and relatively high refractive index (LA>16) but which significantly reduces the amount of Bitumen. and in this case, it also reduces the amount of carbon emissions in the environment. For the production of stone mastic asphalt is used aggregate produced from stone with special mineralogical and petrographic characteristics. The aggregate used for the wearing course of the highway has a coefficient of resistance to crushing Los Angeles LA = 18 and a specific mass greater than 3000kg / m3. Los Angeles coefficient does not meet the standard requirements for the road layer with heavy traffic and the maximum bulk density is greater than the bulk density of ordinary aggregates used for this type of asphalt. Also, for the production of stone mastic asphalt SMA for the highway is used bitumen with additives in the amount of 4.6%, a quantity that is smaller than the amount of bitumen provided by the standard for stone mastic asphalt which is 6-7%. However, the designed mix with the aggregate produced from M.G quarry stone and with the amount of polymerized bitumen (with polymer additives) (4.6%) has met the requirements for SMA stone mastic asphalt it also increases its performance in protecting the environment.