CEMENT ADMIXTURE AND CEMENT COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain both a cement admixture and a cement composition capable of sufficiently suppressing an alkali-aggregate reaction without lowering effects of a water-reducing agent. SOLUTION: This cement admixture comprises lithium bentonite in an Si/Al molar ratio of the lithium bentonite within the range of 1.0-3.0 and the content of Li2O is >=2.0 wt.%. Furthermore, the total amount of Na2O and KaO is <=1.0 wt.% The cement composition comprises a cement and the cement admixture.