A method of preparing and molding a hydraulic cement-containing composition such as concrete or mortar is disclosed, which can be extensively utilized in the fields of civil engineering, construction projects, or the like. In the preparation of a hydraulic cement-containing composition, cement and water, and sand, gravel or the like, if necessary, are kneaded together to cause the hydration reaction. A feature of the present invention resides in preparing a mortar or the like containing water necessary for the hydration reaction in the form of ice pieces and causing the hydration of cement and water to result from the melting of the ice pieces. |