초록 ▼

The present invention relates to a method of preparing a hydraulic binder wherein at least the following two binders are mixed together: a) a first hydraulic binder having as one of its main components the mineral compound C4A3{overscore (S)}; and b) a sulfate second binder based on calcium sulf

The present invention relates to a method of preparing a hydraulic binder wherein at least the following two binders are mixed together: a) a first hydraulic binder having as one of its main components the mineral compound C4A3{overscore (S)}; and b) a sulfate second binder based on calcium sulfate hemihydrate and/or anhydrite obtained by applying heat treatment to gypsum. The present invention also provides a binder comprising amongst its main components: a) a mineral compound C4A3{overscore (S)}; and b) a compound comprising a hemihydrate of calcium sulfate of α or ß form and of general formula CaSO4, ½H2O and/or an anhydrite of III form of general formula CaSO4, &egr;H2O with &egr; lying in the range 0 to 0.5, preferably in the range 0.06 to 0.11, or an anhydrite of II form of formula CaSO4.

대표청구항 ▼

1. A method of preparing a hydraulic binder, comprising the step of mixing two binders comprising: a) at least 50% by weight of a first hydraulic binder, said first binder being sulfoalumina clinker or cement, comprising as its main mineral components C 4A3S, C2S and C4AF, its primary and seconda

1. A method of preparing a hydraulic binder, comprising the step of mixing two binders comprising: a) at least 50% by weight of a first hydraulic binder, said first binder being sulfoalumina clinker or cement, comprising as its main mineral components C 4A3S, C2S and C4AF, its primary and secondary components being selected among C4A3S and C2S and b) less than or equal to 50% by weight of a sulfate second binder, having more than 70% by weight of anhydrite of soluble form III of formula CaSO 4·&egr;H2O, wherein &egr; is in a range from 0.06 to 0.11, and less than 30% by weight of calcium sulfate hemihydrate of α or ß form having a general formula CaSO4½H2O.2. A hydraulic binder produced by the method according to claim 1.3. A binder according to claim 2, wherein said main mineral component of said first binder is C4A3S.4. A hydraulic binder according to claim 2, comprising mineral filler additives selected from the group consisting of slag, fly ash, pozzolan, silica soot, limestone fines, lime, industrial by-products and wastes.5. A method of preparing a hydraulic according to claim 1 wherein in said sulfate second binder the ratio by weight of said hemihydrate to said anhydrite III is less than 15/85.6. A method according to claim 1, wherein the weight ratio of said sulfate binder to said first binder lies in the range 5/95 to 50/50.7. A method according to claim 1, wherein the weight ratio of said sulfate binder to said first binder lies in the range 5/95 to 20/80.8. A hydraulic binder according to claim 2, wherein said first binder, contains: 15% to 75% by weight of said compound C 4A3S.9. A hydraulic binder according to claim 2, wherein said first binder contains: 5% to 35% by weight of said compound C 4A3S.10. A hydraulic binder according to claim 2, having a weight ratio of C4A3S to C2S of 1 to 5.11. A hydraulic binder according to claim 2, comprising: a) 15% to 75% by weight of C 4A3S; and b) 5% to 50% by weight of soluble III anhydrite of calcium sulfate.