CONCRETE COMPOSITION

PROBLEM TO BE SOLVED: To produce a concrete composition using fine aggregate which is capable of being used as a substitute for river sand or sea sand and has sustained sufficient quality and also can be supplied at a low cost, by utilizing decomposed weathered granite as a part or the whole of the fine aggregate of such a concrete composition consisting of bone cement, water, coarse aggregate, fine aggregate and, if necessary, various additives. SOLUTION: In the concrete composition, as fine aggregate, any of washed and unwashed decomposed weathered granite can be used and, as an additive, when unwashed decomposed weathered granite is used, a polycarboxylic acid based high-performance AE (air entraining) water reducing agent is preferably used desirably in an amount sufficient to provide a 1.1-1.5 wt.% ratio of the agent to the weight of cement. Also, though the amount of fine aggregate used can appropriately be selected accordingly to the object to be subjected to execution of construction work, however, the ratio of the fine aggregate to the total weight of the fine and coarse aggregate is desirably 43-47 wt.%. The particle size of decomposed weathered granite used is not particularly limited, however, preferably, the ratio of a fraction of the decomposed weathered granite to its total weight, which fraction is removed by a washing test and passes through a 0.074 mm sieve, is