Effect of the Addition of Thermally Activated Heavy Loam to Portland Cement on the Properties of Cement Stone

Abstract

In the past decades, metakaolin additives synthesized by the calcination of kaolin clays have been implemented in cement systems. Their scarcity and high cost promotes the studies on the effectiveness of thermally activated additives of common polymineral clays. This article presents the results of research on the effect of thermally activated heavy loam additives to Portland cement. It was shown that additives of 5–15% heavy loam calcined at certain temperatures in the range of 400—600°C and ground to a certain specific surface area of up to 250–500 m²/kg lead to a more significant increase in the strength, density, and water resistance of cement stone than corresponding metakaolin additives with the specific surface area of 1200 m²/kg.