| 摘要 |
PROBLEM TO BE SOLVED: To provide a concrete admixture for rapid hardened concrete with which a concrete structure even when removed from forms about 2 to 3 days after concrete placement can develop sufficient hydration expansion, and drying shrinkage and the occurrence of crack of the concrete structure can be remarkably reduced, and to provide concrete using the admixture and a concrete structure construction method. SOLUTION: The concrete admixture for the rapid hardened concrete is a concrete admixture containing quicklime powder and anhydrous gypsum, wherein quick lime powder in the concrete admixture is 30 to 70 mass%, the anhydrous gypsum powder is 70 to 30 mass%, the ignition loss of the quicklime powder is≤6 mass%, the quicklime powder contains CaO at≥90 mass%, and the Blaine specific surface area of the quicklime powder is 4,000 to 6,000 cm<SP>2</SP>/g, and the BET specific surface area is 1.5 to 3.0 m<SP>2</SP>/g. COPYRIGHT: (C)2009,JPO&INPIT |
