| 摘要 |
PROBLEM TO BE SOLVED: To provide a cement admixture and a cement composition excellent in consistency keeping characteristics of concrete, expansion and strength characteristics, and capable of manufacturing a concrete product in a short time. SOLUTION: The cement admixture contains quick lime or a mixture of quick lime, inorganic sulfate and an expansion material, the main constitutional compound of which is 1 or >=2 kinds of hydraulic compounds selected from among free lime, gypsum anhydride, hauyne, calcium ferrite, calcium alumino ferrite, and calcium silicate. The cement composition contains the cement and the cement admixture. Moreover, the concrete is obtained by kneading a mixture composed of the cement composition, and the admixture and water added thereto. The concrete product is manufactured by casting the concrete into a form. |
