Abstract: The present invention relates to a process for producing a powdery dispersant for preparing hydraulic compositions, which process includes adding an reducing agent to a solution predominantly containing a polycarboxylate polymer compound having a polyalkylene glycol chain, drying the resultant mixture, and pulverizing the dried product; the resultant powdery dispersant for preparing hydraulic compositions; and a hydraulic composition containing the dispersant. According to the present invention, there can be provided a powdery dispersant for preparing a hydraulic composition, which has excellent fluidity and dispersibility. The dispersant can be added to cement in advance.

Abstract: A cement composition comprising a cement base and hemicellulose. The cement composition produces reduced efforescence and less bleeding. Self-leveling materials containing the cement composition also produce reduced efforescence and less bleeding and exhibit improved surface adhesion strength.

Abstract: A demolition agent which acts by means of expansive stress generated upon hydration and which is prepared by calcining limestone at 1300.degree. to 1600.degree. C. to produce a hard-burned quick lime whose crystal sizes are 10 to 100 micron, pulverizing the resulting hard-burned quick lime to 1500 to 5000 cm.sup.2 /g (Blaine), mixing 5 to 70 parts by weight of a hydraulic material to 30 to 95 parts by weight of the hard-burned quick lime and furthermore adding 0.1 to 5 parts by weight of an admixture comprising a water reducing agent to 100 parts by weight of the mixture of the powdery hard-burned quick lime and the hydraulic material.The demolition agent is used as an aqueous slurry. The slurry is filled into holes of a brittle material to demolish the brittle material by means of expansive stress generated upon hydration.