Improvement of the technology for crushed stone-mastic asphalt concrete mixtures preparation according to the volume-functional design system

By example of crushed stone-mastic asphalt concrete mixtures, it was found how various technological modes and parameters affect their properties. A modified technological scheme for the hot crushed stone-mastic asphalt-concrete mixtures preparation is proposed. It is shown that temperature and the asphalt-concrete mixture feeding sequence optimization have a significant impact on the physico-mechanical and operational characteristics: average track depth decrease, maximum relative tensile strain and Marshall deformation increase, tensile strength during bending and the destructive load according to Marshall lincrease. According to the experimental data obtained, the optimal temperature for the modified technology is 165±1.5°C. The tests performed showed the mixture complete mixing time to homogeneity was reduced by 20% relative to the mixture standard method preparation. It was found that increase of the asphalt concrete physico-mechanical and operational characteristics using the proposed mixture preparation is a result of the bitumen binder better distribution due to the filler and binder actual contact area increase, which significantly improves the coarse mineral aggregate grains surface wetting with bitumen.