Hydraulic material composition having high strength

A hydraulic material composition comprising a hydraulic material having a particle size of 10-30 .mu.m, ultra-fine particles, a water reducing agent and water, said hydraulic material being selected from the group consisting of mineral materials, combinations of activators and materials having hydraulic activities other than cements and mixtures thereof and containing no aluminate phase consisting essentially of 3CaO.Al.sub.2 O.sub.3 and 4CaO.Al.sub.2 O.sub.3.Fe.sub.2 O.sub.3, said mineral materials being selected from the group consisting of mineral materials of Ca.sub.3 SiO.sub.5, solid solutions of Ca.sub.3 SiO.sub.5 and mixtures thereof, said material having hydraulic activity being blast furnace slag, said activator being selected from the group consisting of cements, calcium hydroxide, calcium oxide, quick lime, calcium sulfoaluminate minerals, inorganic and organic alkaline salts and mixtures thereof, said ultra-fine particles being selected from the group consisting of siliceous dust, calcium carbonate, silica gel, opalic silica, fly ash, blast furnace slag, titanium oxide, aluminum oxide, mineral materials of Ca.sub.3 SiO.sub.5, solid solutions of Ca.sub.3 SiO.sub.5 and mixtures thereof, each of said ultra-fine particles having an average particle size of not more than 3 .mu.m, said hydraulic material composition comprising 60 to 95 parts by weight of said hydraulic material and 5 to 40 parts by weight of said ultra-fine particles, not more than 10 parts by weight of said water reducing agent being contained in 100 parts by weight of said hydraulic material, 100 parts by weight of said hydraulic material and said ultra-fine particles being admixed with 10 to 30 parts by weight of water, 100 parts by weight of said material having hydraulic activity being mixed with not more than 100 parts by weight of said activator.