A study was made of aggregates used for the production of decorative concretes. Since slabs of these concretes are planned to be used for floors and platforms that are subject to high mechanical stress, aggregates must have the necessary properties. The resistance of crushed stone to impact on a copra, abrasion in a shelf drum and frost resistance were studied. For sands used as aggregates, such characteristics as granulometric composition, particle size modulus, stability of the stabilized mixture, etc. were determined. According to the results obtained, aggregate samples were determined that are most suitable for the production of decorative concrete, which are used for the installation of decorative floors and platforms.

Keywords: wear-resistant materials, decorative effect, size modulus, crushed sand, crushed stone

Hardening of concrete in the conditions of a construction site under constantly changing temperature and humidity conditions does not provide the desired performance properties of concrete and reinforced concrete structures. An assessment was made of the influence of the conditions of hardening of concrete samples at a water-cement ratio (W / C) of 0.45 and a hardening of 28 days. The hardening of concrete samples took place under conditions of a normal hardening chamber (air temperature T = 20 ± 50С, humidity W = 90 ± 2%), samples in water when completely immersed in a bath at water temperature T = 20 ± 30С and samples immersed in a plastic bag , hardening in the conditions of the air environment of the laboratory (T=20±50C). The samples gain the greatest strength when hardening completely immersed in water, and the smallest when hardening in an insulating polyethylene sheath.

Keywords: concrete scrap, fractionated crushed stone, water-cement ratio, hardening conditions, clinker hydration, strength development kinetics, moisture migration