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Документ Influence of whitening additives on the properties of decorative slag-alkaline cements(IOP Publishing Ltd, 2020-09) Gots, V. I.; Gelevera, O. G.; Petropavlovsky, O. N.; Rogozina, N. V.; Smeshko, V. V.Traditional decorative cements are made on the basis of white cements and the demand for them is constantly growing. But such cements have all the disadvantages of clinker cements, namely, high energy intensity and high price. An alternative may be slag-alkali cements having higher physical and mechanical characteristics and lower price. Therefore, these studies were aimed at choosing such additives that would have the maximum whitening properties and would enhance the stabilization of bleaching processes during hydration and hardening of slag in the presence of alkalis, to determine the simultaneous effect of three additives on the whiteness and physical-mechanical characteristics, as well as to determine the optimal the content of these additives in slag-alkali decorative compositions. In this work, as a result of the studies performed, the possibility of obtaining effective slag-alkali white cements as the basis for the production of decorative concrete with acceptable economic characteristics is proved. The influence of each of the bleaches on such characteristics of decorative slagalkali cements as strength, setting time, whiteness is established. Methods for optimizing compositions are identified.Документ Enhancement of alkali-activated slag cement concretes crack resistance for mitigation of steel reinforcement corrosion(EDP Sciences, 2020-04-22) Petropavlovskyi, Oleh; Kovalchuk, Oleksandr; Krivenko, Pavlo; Rudenko, Igor; Konstantynovskyi, OleksandrThe paper is devoted to mitigation of steel reinforcement corrosion in alkali-activated slag cement (further, AASC) concretes, based on soluble sodium silicates (further, SSS's), obtained from high consistensy concrete mixes. Enhancement of AASC fine concretes crack resistance due to modification by complex shrinkage-reducing additives (further, SRA's) based on surfactants and trisodium phosphate Na3PO .12H2O (further, TSP) was proposed for mitigation of steel reinforcement corrosion. SSS's were presented by sodium metasilicate (silica modulus 1.0, dry state) and water glass (silica modulus 2.9, density 1400 kg/m3). In case of sodium metasilicate the application of SRA composition "ordinary portland cement clinker - TSP - sodium lignosulphonate - sodium gluconate" provides enhancement of crack resistance starting from early age structure formation with restriction of drying shrinkage from 0,984 to 0,713 mm/m after 80 d. The effect is caused by reduction of water and by higher volume of crystalline hydrates. In turn, SRA presented by compositions "TSP - glycerol" and "TSP - glycerol - polyacrylamide" provide enhancement of AASC fine concretes fracture toughness during late structure formation with increasing ratio of tensile strength in bending to compressive strength up to 37 - 49 % if compare with the reference AASC when water glass is used.