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Документ The efficiency of plasticizing surfactants in alkali-activated cement mortars and concretes(EDP Sciences, 2018) Runova, Raisa; Gots, Volodymyr; Rudenko, Igor; Konstantynovskyi, Oleksandr; Lastivka, Oles’Functionality of mortar and concrete mixes is regulated by surfactants, which act as plasticizers. The molecular structure of these admixtures can be changed during hydration of alkali-activated cements (AAC). The objective was to determine the chemical nature of plasticizers effective for property modification of mortars and concretes based on AACs with changing content of granulated blast furnace slag from 0 to 100 %. The admixtures without ester links become more effective than polyesters when content of alkaline component increase. The admixtures effective in high alkaline medium were used in dry mixes for anchoring (consistency of mortar 150 mm by Vicat cone; 1 d tensile strength in bending / compressive strength of mortar 6.6 /30.6 MPа) and in readymixed concretes (consistency class changed from S1 to S3, S4 with consistency safety during 60 min; 3 d compressive strength of modified concrete was not less than the reference one without admixtures).Документ The efficiency of plasticizing surfactants in alkali-activated cement mortars and concretes(Transbud-2018, 2018) Runova, Raisa; Gots, Volodymyr; Rudenko, Igor; Konstantynovskyi, Oleksandr; Lastivka, Oles’Functionality of mortar and concrete mixes is regulated by surfactants, which act as plasticizers. The molecular structure of these admixtures can be changed during hydration of alkali-activated cements (AAC). The objective was to determine the chemical nature of plasticizers effective for property modification of mortars and concretes based on AACs with changing content of granulated blast furnace slag from 0 to 100 %. The admixtures without ester links become more effective than polyesters when content of alkaline component increase. The admixtures effective in high alkaline medium were used in dry mixes for anchoring (consistency of mortar 150 mm by Vicat cone; 1 d tensile strength in bending / compressive strength of mortar 6.6 /30.6 MPа) and in readymixed concretes (consistency class changed from S1 to S3, S4 with consistency safety during 60 min; 3 d compressive strength of modified concrete was not less than the reference one without admixtures).Документ 35. The influence of complex additive on strength and proper deformations of alkali-activated slag cements(Trans Tech Publications Ltd, 2019) Krivenko, Pavel; Petropavlovskyi, Oleh; Rudenko, Igor; Konstantynovskyi, OleksandrThe peculiarity of alkali-activated slag cements (further, AASC’s) is increased proper deformations, which can cause increased cracking and reduced durability of structure. The paper is devoted to manage AASC’s proper deformations. The main task was to determine the composition of complex additives (further, CA’s) in system «ordinary portland cement (further, OPC) clinker -mineral compound of different anionic type - surfactant» in presence of sodium metasilicate (further, MS) to affect on hydrated AASC performance while ensuring effective structure of artificial stone by criterion of shrinkage deformations. Comparative analysis of hydrated cement systems "OPC clinker - MS", "OPC clinker - mineral compound - MS" and "OPC clinker - mineral compound - MS - surfactant" showed that the greatest effect on reduction of proper deformations occurs when the mineral compounds relate to electrolytes, i.e. Na2SO4 and NaNO3. Hydrated system is characterized by expansion (+0,062 mm/m) in presence of Na2SO4. Almost no shrinkage is supplied by application of NaNO3 (-0,062 mm/m). The obtained CA’s were tested in AASC. CA in the system “OPC clinker - NaNO3 - surfactant” provides the initial setting 43 min, the end - 65 min with accelerated strength. Investigated AASC can be classified as non-shrinking cement. This phenomena is ensured by increasing density, homogeneity and monolithicity of hydrosilicate formations, as well as due to formation of hydroaluminosilicate structures with different morphology by inclusion of nitrate anions.