Effect of expansion additive synthesized using kaolin from Zhuravliny Log field on cement hardening

The properties of expansion additive synthesized by calcining kaolin from Zhuravliny Log deposit, limestone and natural gypsum mixed to an optimal ratio, in the range of 1000-1300°C. The agent synthesized at the optimum burning temperature (1200°C), is similar in its effect to the Denka CSA 20 additive. It was found that the expansion of the cement paste with the additive is provided through the formation of ettringite phase, and SaOfree hydration reaction. Adding 5% of the agent to the mortar ensures no shrinkage of the mortar; increase in the additive content to 10-15% provides for expansion during curing.

Author: I.N. Medvedeva, S.A. Krasnobayeva, M.E. Voronkov, A.S. Brykov, Z.V. Stafeeva

Section: Science and production

Keywords: kaolin, expansion admixture, Portland cement