CONCRETE COMPOSITION USING BLAST-FURNACE CEMENT

PROBLEM TO BE SOLVED: To provide a concrete composition, while suppressing the exhaust amount of carbon dioxide, which can secure satisfactory applicability in a state where the reduction in the fluidity and the reduction in an air amount with the lapse of time in the prepared concrete composition are suppressed, further can suppress the drying shrinkage of the obtained hardened body, and can make the required strength appear in the obtained hardened body as well. SOLUTION: The concrete composition at least comprises cement, water, fine aggregate, coarse aggregate and an admixture. As the cement, the following blast-furnace cement is used, also, the ratio of the water/the blast-furnace cement is regulated to 20 to 60%, and further, per 100 pts.mass of the blast-furnace cement, as at least a part of the admixture, a specified cement dispersant, a specified drying shrinkage reducer and a specified setting accelerator are comprised by prescribed amounts. The blast-furnace cement comprises blast-furnace slag fine powder having fineness of 3,000 to 13,000 cm2/g and portland cement, and also, the blast-furnace slag fine powder is comprised by 60 to 80 mass% and the portland cement is comprised by 20 to 40 mass% (total 100 mass%). COPYRIGHT: (C)2011,JPO&INPIT