| 摘要 |
PROBLEM TO BE SOLVED: To provide a cement admixture and cement composition for a mass concrete which is effective for suppressing a temperature crack of the mass concrete, which has a good storage stability without causing a setting retardation, moreover wherein an addition amount is reduced. SOLUTION: In the cement admixture for the mass concrete, an expanding material containing free lime and one or more kinds of hydraulic compounds selected from among hauyne, calcium silicate, calcium ferrite and calcium aluminoferrite, and the expanding material containing the free lime and anhydrous gypsum, further the expanding material containing the free lime, the hydraulic compounds and the anhydrous gypsum are used as an included substance, and the expanding material is capsulated with a capsule membrane agent. In the cement admixture for the massive concrete, the capsule membrane agent is a wax, a hardened oil or a paraffine. The cement composition contains the cement and the cement admixture for the mass concrete. COPYRIGHT: (C)2010,JPO&INPIT |
