The article presents a study of changes in the mineralogical composition of cement when adding microsilica of different concentrations using diffractometer DRON-3 with СuCa-radiation, β-filter. X-ray phase analysis on a semi-quantitative basis was carried out on powder sample diffractograms using the method of equal weights and artificial mixtures. The work examines the effects of microsilica on the mineralogical composition of cement at the microstructural level. The aim of the study was to improve the physico-chemical properties of the cement. Solutions with different percentages of microsilica additives (0, 10%, 20%, 30%) were made for the analysis. The conducted research makes it possible to determine the effect of microsilica in different concentrations on the properties of the cement composition. The introduction of additive into products is introduced to increase mechanical properties, reduce porosity, increase water resistance and durability of products, possibly due to binding of calcium hydroxide in the structure of hardening cement stone by dispersions of microsilica. In general it can be concluded from the results of studies that the additive contributes to increasing the strength of the mixture, accelerating hardening. Consequently, the additive is one of the most effective additives to increase the strength.

The article presents results of the effect of one component of the modified additive (post alcohol bard) on the change in the setting time of the cement mixture. The work shows a method for determining the setting time, the selection of optimal composition of samples, which will accelerate the setting time (beginning and end). Performed a comparative study of cements from different manufacturers, as well as the effect of one component of the modified additive (post-alcohol bard) on the setting time. The research allows to determine the effect of plasticizing additive on the properties of foam concrete during their production. It is established that the introduction of the additive can reduce the time of the beginning and the end of setting, the introduction of additive (post-alcohol bard) in optimal quantities will accelerate the process of making foam concrete products. Obtained results of setting time in the samples using the additive led to the best results. In general according to the results of studies it can be concluded that the additive promotes the growth rate of plastic strength and setting of foam concrete mixture, accelerates the hardening of foam concrete and can reduce its shrinkage during hardening. Consequently, the additive is one of the most effective additives to accelerate setting and allows mortars to fully set in the shortest time intervals.

The given article is devoted to research of influence of polymer modifiers and mineral additives on quality of composite aerated concrete products. When selecting the composition of composite aerated concrete local raw materials and components were used: portland cement, sand, aluminum powder, polyvinyl acetate, fly ash, post-alcoholic bard and whey of milk. Preliminary polyvinyl acetate was combined with binder mixing water at a temperature above 55ºC to obtain a readily soluble polymer emulsion. Dispersion was carried out with a rotary-pulsation apparatus at a pressure of 0.5-1.0 MPa and a rotor speed of ~1200 rpm. In the same apparatus the complex modifier was produced. The offered technology of production of a complex modifier seems to be the most effective for composite aerated concrete. It made it possible to reduce water absorption and capillary suction of composite aerated concrete by an average of 25% and 45%, respectively. Moreover, different combinations of fly ash, polymer and modifier made it possible to achieve optimal values of thermal conductivity, compressive strength and frost resistance of composite aerated concrete.

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