A method for the application of hydrous mineral binder compositions which contain fibres. An aqueous accelerator is mixed with the aqueous binder composition in a mixer shortly before the application. The method is very robust and makes it possible to quickly produce even large moulded bodies having a uniform surface and very good strength development properties.

A method for the application of hydrous mineral binder compositions which contain fibres. An aqueous accelerator is mixed with the aqueous binder composition in a mixer shortly before the application. The method is very robust and makes it possible to quickly produce even large moulded bodies having a uniform surface and very good strength development properties.

Corrosion mitigating cement compositions and methods for their preparation are provided. The cement compositions are derived from self-cementing pozzolans and chemical accelerators, retarders, mechanical strength modifiers and corrosion inhibitors. The corrosion inhibitors include boron compounds such as boric acid. Concretes prepared using the cement compositions possess low conductivity and a conductivity which further decreases with aging.

Corrosion mitigating cement compositions and methods for their preparation are provided. The cement compositions are derived from self-cementing pozzolans and chemical accelerators, retarders, mechanical strength modifiers and corrosion inhibitors. The corrosion inhibitors include boron compounds such as boric acid. Concretes prepared using the cement compositions possess low conductivity and a conductivity which further decreases with aging.

Corrosion mitigating cement compositions and methods for their preparation are provided. The cement compositions are derived from self-cementing pozzolans and chemical accelerators, retarders, mechanical strength modifiers and corrosion inhibitors. The corrosion inhibitors include boron compounds such as boric acid. Concretes prepared using the cement compositions possess low conductivity and a conductivity which further decreases with aging.

This invention discloses a double-liquid grouting slurry, its technology and application for super large diameter underwater shield engineering under high water pressure condition. The materials of slurry I are: 35-45 parts of cement clinker; 15-25 parts of slag; 24-35 parts of fly ash; 15-25 parts of steel slag; 5-15 parts of bentonite; 4-10 parts of limestone tailing; 0.3-2.0 parts of water reducing agent; 0.5-2.5 parts of cellulose. The materials of slurry II are: 0.2-3.8 parts of short-cut fiber; 96-99 parts of sodium silicate solution; 0.8-4.8 parts of viscous polymers. This invention generates the double-liquid slurry preparation process including crushing-screening-milling-group mixing-grouped mixing at different speeds, the volume ratio of slurry I and II is 1:1-10:1 during grouting, and the slurry is injected into the shield void through the six-point position technology at the shield tail and 3+2+1 segment splicing synchronous grouting techniques.

A synchronous single-liquid grouting slurry, its technology and application for large diameter shield engineering under water-rich, high-pressure and weak soil strata conditions, comprising raw materials: 1050-1200 parts of gold tailing, 420-480 parts of silicate cement clinker, 220-240 parts of fly ash, 45-120 parts of waste clay brick, 65-95 parts of slag, 25-45 parts of limestone tailing, 70-80 parts of steel slag, 30-45 parts of silica fume, 15-22 parts of desulfurized gypsum, and 9-15 parts of quick-setting and early-strength composite additive. The invention controls the d.sub.50, d.sub.85 and d.sub.95 of the material particles as 35-40, 42-48 and 50-55 μm, respectively. Gold tailing with the particle size of 120-600 μm being used as the fine aggregate, their volume fractions are 40-60%. The slurry production technique, comprising crushing-sieving-superfine ball milling-homogenization-particle size classification-variable speed mixing being developed. The shield tail eight-point grouting technique is being developed for filling.

A powdered quick-setting agent containing a calcium aluminate and a sodium silicate, preferably further containing at least one selected from the group consisting of an alkali metal sulfate, an alkaline earth metal sulfate, and an aluminum sulfate.

A powdered quick-setting agent containing a calcium aluminate and a sodium silicate, preferably further containing at least one selected from the group consisting of an alkali metal sulfate, an alkaline earth metal sulfate, and an aluminum sulfate.

A powdered quick-setting agent containing a calcium aluminate and a sodium silicate, preferably further containing at least one selected from the group consisting of an alkali metal sulfate, an alkaline earth metal sulfate, and an aluminum sulfate.