A use of a thiosulfate as a retarder for a cement paste comprising a magnesium phosphate cement.

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.

Various embodiments disclosed relate to cement activator compositions for treatment of subterranean formations. In various embodiments, the present invention provides a method of treating a subterranean formation including placing in the subterranean formation a liquid cement activator composition including water, an alkali sulfate salt, a polyphosphate salt, and a stabilizer polymer.

Various embodiments disclosed relate to cement activator compositions for treatment of subterranean formations. In various embodiments, the present invention provides a method of treating a subterranean formation including placing in the subterranean formation a liquid cement activator composition including water, an alkali sulfate salt, a polyphosphate salt, and a stabilizer polymer.

The present invention relates to a compact and highly dense engineered concrete binder composition and a method of producing the same. In particular, the engineered concrete binder composition comprises at least one mechano-chemically modified component.

The present invention relates to a compact and highly dense engineered concrete binder composition and a method of producing the same. In particular, the engineered concrete binder composition comprises at least one mechano-chemically modified component.

An inorganic mortar system for chemical fastening of an anchor in mineral substrates can contain at least one hard aggregate having a Mohs-hardness of greater than or equal to 8. The inorganic mortar system contains a curable aluminous cement component A and an initiator component B for initiating the curing process. Component A contains at least one blocking agent selected from boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, phosphoric acid, and salts and mixtures thereof. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. The use of at least one hard aggregate having a Mohs-hardness of greater than or equal to 8 in an inorganic mortar increases load values and reduces shrinkage. A method can be used for chemical fastening of an anchor, preferably of metal elements, in mineral substrates, such as structures made of brickwork, concrete, pervious concrete, or natural stone.

A two-component system for forming adhesive bonds or for chemical anchoring comprises a curable binder component A and an activator component B. The component A comprises: A-1) an inhibited hydraulic binder selected from among calcium aluminate cement, calcium sulfoaluminate cement and mixtures thereof; the component B comprises: B-1) a curing activator. At least one of the components A and/or B comprises: V-1) an organic binder; and V-2) a filler having a Mohs hardness of at least 5. The system is an aqueous system which is unproblematical from a health point of view. It is easy to process and quickly attains high strengths.