Composite cement with dispersed perlite and colloidal additive for hydraulic concrete

The article considers the possibility of obtaining composite cement for hydraulic engineering using finely dispersed aluminosilicate rocks - perlites, a colloidal additive in the form of silica sol and a superplasticizer to increase the crack resistance of hydraulic concrete. The kinetics of cement stone hardening using vitreous and crystallized perlite with varying degrees of dispersion, colloidal additive and a superplasticizer are considered. Studies of the structure formation of cement stone modified with a colloidal additive and finely dispersed perlite at the ages of 3 and 28 days have been carried out.
It is proved that with the addition of finely dispersed perlite and a superplasticizer to Portland cement, it is possible to obtain a composite cement with strength not lower than that of the initial cement and with less heat dissipation during hydration compared to traditional compositions. The most rational formulations of composite cement contain 10-20 % of vitreous perlite with a specific surface of 400-600 m2/kg, a colloidal additive and a superplasticizer, providing an increase in the strength of the cement matrix at the age of 28 days by 30-40 % compared to the control composition. For compositions with vitreous and crystallized perlite, silica sol and a superplasticizer, the temperature on the 1st and 2nd day of hydration is lower than that of control compositions by 12.7-14.1 and 11.0-13.3 %, respectively.

Author: L.A. Urkhanova,, A.A. Ivanov, S.A. Lkhasaranov

Section: Science and production

Keywords: plasticizing additive, silicic acid sol, composite cement, vitreous perlite, crystallized perlite, degree of dispersion, specific surface area, heat dissipation, compressive strength, hydraulic concrete