Calcium aluminate fast-acting admixture

摘要

PROBLEM TO BE SOLVED: To provide a calcium laminate rapid hardening additive, which suppresses chromatic color development of a hardened body of a hydraulic composition using the additive without reducing the rapid hardening property, and makes the surface color tone of the hardened body substantially the same as that of a cement-based hydraulic composition which does not contain calcium aluminate.SOLUTION: Provided is a calcium aluminate rapid hardening additive containing as a main component calcium aluminate having a total iron content of 0.5 to 2 mass% and a trivalent iron content of 0.5 mass% or less, and a vitrification rate of 53% or less.