MINERAL POWDER AS A TOOL FOR REGULATING THE QUALITY OF ASPHALT CONCRETE MIXTURES

The study is devoted to the analysis of mineral powders used in asphalt concrete mixtures. The object of study is powders of various origins: carbonate rocks (limestone, dolomite), zeolites, perlite, industrial waste (fly ash, slags, sewage sludge), as well as methods of their activation. Special attention is paid to the influence of the chemical composition, porosity and dispersion of mineral fillers on the properties of the asphalt binder and asphalt concrete. The paper uses methods of comparative prospecting and theoretical analysis and systematization of existing Russian and foreign studies of mineral powders of various natures, physical and mechanical characteristics of asphalt concrete based on them, mechanical and chemical activation of such powders, and assessment of bitumen adhesion to mineral components. Technologies for modifying fillers using surfactants, nanomaterials, and hydrophobizers are considered. It has been found that the use of alternative powders (based on zeolites, man-made waste) increases the strength, water resistance and thermal stability of asphalt concrete by 20-30%, organic mineral powders from sewage sludge reduce water saturation by 20%, and the use of slag and fly ash in the production of mineral powders contributes to solving environmental problems through waste disposal. It is shown that the activation of mineral fillers reduces bitumen consumption by 10-15%, improves the structuring of the composite and increases the durability of coatings.