It is proposed to distinguish the false setting from the abnormal one, considering the false as a variety of the latter. With false setting, the start of setting occurs in a short time, but then it spontaneously disappears, reappearing after a while. Such cements, in which the beginning of setting occurs faster than 50 minutes, and the end – after 5-12 hours, are proposed to be called abnormal cements. It is shown that when the start time of setting is more than 50 ∼ 60 minutes, the probability of abnormal setting decreases sharply. The kinetics of structure formation of cements with different setting patterns is considered. Methods for the identification of abnormal setting by the setting interval (τfinal – τstart)/τstart > 3, the kinetics of structure formation, heat release, and changes in the activity of calcium ions in the liquid phase of cement paste of normal density are proposed. It is shown that the measurement of the kinetics of heat release and the activity of Ca 2+ ions in the liquid phase of cement paste is of great interest for the development of automated and rapid control of the presence of anomalies during setting. It is established that the mixture of the inhibitor and the booster of the setting acts according to the rule of additivity, the use of mineral additives of acidic composition weakens the abnormal properties of cement systems. To combat the belated anomaly, it is necessary to monitor the properties of the cement 1-2 days before its application.

The study showed that in order to accelerate the hydration of inorganic binders it is necessary to use additives of such electrolytes that increase the concentration of calcium ions in the liquid phase of the cement suspension. Electrolytes (soda ash, sodium and potassium hydroxides), precipitating calcium ions in the liquid phase, promote their exit from the "shut-off" layer of hydration products. In this paper, we studied the additives – electrolytes – as regulators of the setting time of fine-grained and porous concrete. To increase the activity of the additive as a concrete mixtures setting time regulator, acidic varieties were used instead of main salts. The studied additives – electrolytes – draw practical interest, as their usage in production of foam concrete and fine-grained concrete lets accelerate hardening of products and speed up reuse of mould.

A hypothesis about the mechanism of reducing shrinkage deformations under the influence of organic additives is presented. It may become the basis for the search for new additives that reduce the cement stone shrinkage by preventing the convergence of parallel surfaces of new formations due to electrosurface interactions with the functional group of the additive. The results of the study of the shrinkage of foam concrete with the addition of citric and sulfanilic acids are presented. It was found that they reduce shrinkage deformations by up to 76% with follow-up periods of up to 60 days. The proposed scheme of the action of additives on shrinkage allows us to conduct a directed search for surfactants that reduce the shrinkage deformations of foam cement stone

The work is devoted to the study of the relationship between the individual clinker minerals content, the stone compressive strength in different periods of hardening and the binders kinetic hardening constants. It is shown that C3S and C2S affect the cements’ kinetic hardening constants in the early and long-term periods in different ways. There is a positive effect of C2S on the ultimate compressive strength and a sharp decrease in the dependence of the stone ultimate strength on C3S in the later periods. The initial hardening rate in high-cement cement is established to increase sharply with an increase in the C3A content from 5 to 12%. The increase in the C3A content up to 12% in low-cement cement has little effect on the initial hardening rate value.

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