PRODUCTION OF CEMENT COMPOSITION

PROBLEM TO BE SOLVED: To provide a production process of a cement composition such as concrete or mortar, which is excellent in workability immediately after mixing. SOLUTION: This production process comprises: adding a high solubility calcium salt to a mixed base material containing at least cement, water and an aggregate, after mixing and further mixing them, wherein the post-addition of the high solubility calcium salt is performed after a lapse of 15-120 min from a time point at which the mixing of the base material containing at least the cement, water and aggregate is initiated; also, the amount of addition of the high solubility calcium salt is 0.15-1.5 pts.wt., expressed in terms of its anhydrate, on the basis of 100 pts.wt. of cement preferably containing 50-75 wt.% 3CaO.SiO2; and a high polymer compound having carboxyl groups is preferably further added as a chemical admixture to the base mixed material.