摘要 |
PROBLEM TO BE SOLVED: To provide a cement composition which exhibits excellent flowability stably immediately after kneading and also causes little change with time in flowability without depending on the brand (kind) of dispersants, in concrete having a low water/cement ratio and using a polycarboxylic acid-based dispersant. SOLUTION: The cement composition contains cement clinker and gypsum. In the cement composition, the content of hemihydrate gypsum is 0.2-3.5 mass%, the ratio of the amount of the hemihydrate gypsum to the total amount of the hemihydrate gypsum and dihydrate gypsum is 50-95 mass%, and the content of water-soluble alkali is 0.17-0.32 mass%. The particles obtained by pulverizing the cement composition have a stuck water amount of 0.003-1.0 mass% based on the cement composition. COPYRIGHT: (C)2007,JPO&INPIT |