Özet:

The chemical processes of Portland cement hydration enable the formation of concrete compressive strength. Under certain conditions, increasing the rate of cement hydration contributes to the improved strength of concrete at compression. This is especially true of the cellular concretes, specifically aerated concretes. The current work has investigated the influence of an integrated admixture that promotes gas formation in obtaining aerated concrete. The specified admixture consists of a mixture of hydrophobic surface-active substance – calcium oleate, perhydrol, and a nanomodifier, a mineral additive containing iron compounds. Feature of this research was the study into a simultaneous influence of hydrophobic surface-active substances, perhydrol, and mineral substances containing iron compounds, on a change in the strength of non-autoclave aerated concrete. The study was necessitated by the insufficient compressive strength of non-autoclave aerated concretes, whose manufacture employs aluminum powder or perhydrol as a gas-forming additive. Using aluminum powder does not provide for the homogeneity of its distribution throughout the volume of concrete; in addition, the cost of aluminum powder is rather high. It was established in the course of our study that the specified integrated admixture changes the character of strength formation in aerated concretes, specifically it increases its magnitude. It has been proven that in order to control the processes of cement hardening and to form the strength of artificial stone, which is obtained in the process of cement hydration, it is possible, in the manufacture of aerated concrete based on perhydrol, to use the admixtures-nanomodifiers containing compounds of iron, thereby improving the absolute magnitude of compressive strength of such concretes at the age of 28 days. The most effective is to use the nanomodifiers that contain a mixture of iron compounds, which leads to an increase in the strength of aerated concrete by up to 50 %. Author Biographies Alexsandera Shishkina, Kryvyi Rih National University Vitaly Matusevicha str., 11, Kryvyi Rih, Ukraine, 50027 PhD, Associate Professor Department of Technology of Building Products, Materials and Structures

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