Chemical additives, namely, plasticizers and superplasticizers are effective modifiers of the concrete mix properties and structures. The additives allow to control properties of the concrete mix and to obtain its optimal structure, acting on the surface phenomena and microstructure of the cement paste. In the course of the study, the effect of introducing the superplasticizer SP-2VU into the concrete mix is studied. This allows to modify the construction and engineering properties of concrete. Analysis of the data obtained in determining the setting speed of the system based on cement and various concentrations of the regulator shows that the introduction of SP-2VU into the cement mortar leads to a significant slowdown in the process of setting the binder composition in comparison with additive-free cement, slowing the cement setting from ~ 2 hours to ~ 12.5 hours. In addition, the superplasticizer in an amount of up to 0.5 % contributes to some preservation of the cement mixture mobility to ~5 h, while in the absence of an additional composition - up to ~2.5 h. The SP-2VU (to a concentration of 0.7 %) increases the strength of modified concrete compared to conventional. Moreover, the optimal concentration of the additive (0.5 %) is established, which contributes to the set of the required speed of structure formation of the system and the formation of strong hardening structures with a more ordered, stable solidified structure and certain performance characteristics. At the same time, the strength of samples containing 0.5 % of the modifier in the concrete mixture increases by 40 %.
Early structure formation of foam concrete mix containing modifying admixture
