| 摘要 |
PROBLEM TO BE SOLVED: To provide a water-hardenable hardened body which has sufficient strength and can substantially reduce discharge of CO.SOLUTION: A water-hardenable hardened body is obtained by kneading fine powder of concrete sludge, aggregate and, if necessary, additives. The fine powder of concrete sludge is obtained from residual concrete or return concrete. A dehydrated cake is obtained by adding water to residual concrete or return concrete to prepare slurry, removing ballast, sand and fine sand from the slurry to obtain sludge water and dehydrating the sludge water, and the dehydrated cake is charged into a specified rotary drum to be blown with hot air and crushed and dried to obtain fine powder of concrete sludge. The fine powder of concrete sludge has a specific surface area of 8,000 cm/g or smaller. |
