MORTAR OR CONCRETE COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain a mortar or a concrete composition, capable of quickly and simply judging the usability thereof as an admixture for a cement or a concrete by typical characteristics, ensuring the use of a large amount of coal ash (fly ash) and a prescribed fluidity and air-entraining properties and good in development of the strength. SOLUTION: This composition is a mixture containing a coal ash therein and has a weight ratio of cement/coal ash represented by any one of the following (1) to (3): (1) when a pH value of a 20% aqueous slurry of the coal ash is >=11.0, the cement/coal ash weight ratio is >=0.5; (2) when a pH value of the 20% aqueous slurry of the coal ash is >=9.0 but <11.0, the cement/coal ash weight ratio is >=0.7 and (3) when a pH value of the 20% aqueous slurry of the coal ash is >=6.0 but <9.0, the cement/coal ash weight ratio is >=1.0.