MANUFACTURE OF MORTAR AND CONCRETE

PURPOSE:To greatly improve the capacity of mortar or concrete, by a method wherein during falling of a cement composition, spraying is performed homogeneously by making use of a specific quantity of water containing a cement additive or that not containing the cement additive, during that time the cement composition is subjected to treatment where the cement composition receives a shearing action. CONSTITUTION:A powdery cement composition is caused to fall under a state where each ingredient in a homogeneously distributed and dispersed condition by centrifugal force based on rotary motion while the composition is being fed continuously as a specific treatment to the composition. A continuous mixer F is used suitably. Spraying to a cement composition is performed during falling of the cement composition so that water is distributed homogeneously by making use of the water containing a cement additive or that not containing the same at a quantity of 0.1-10pts.wt. on the basis of 100pts.wt. cement. An appropriate quantity of the water is stuck to the surfaces of cement particles and a cement hydrated layer containing etiolinguite or a mineral similar to the etiolinguite is formed on the surface. It is necessary that an interval of time until the powdery cement composition comes into contact with the next kneaded water is made at least three minutes, in the powder cement composi tion to which specific treatment is performed.