An accelerator powder for cement and also rapid-setting binder compositions which contain the accelerator powder and the use in mortar or concrete. The accelerator powder includes from 10 to 99.7% by weight of a water-insoluble mineral powder P and from 0.3 to 90% by weight of at least one compound V selected from the group consisting of alkali metal halides and alkaline earth metal halides, alkali metal nitrates and alkaline earth metal nitrates, alkali metal nitrites and alkaline earth metal nitrites, alkali metal thiocyanates and alkaline earth metal thiocyanates and hydroxyalkylamines or salts thereof, and mixtures thereof.

The present invention relates to a process for preparing a metal-chelate retarder by a sol-gel method. The method comprises the following steps: weighing calcium nitrate tetrahydrate, aluminum nitrate nonahydrate and ferric nitrate nonahydrate according to a certain mass ratio and adding them into deionized water; placing the mixed solution on a magnetic stirrer and stirring the mixed solution evenly; adding citric acid monohydrate or gluconic acid, ethylene glycol or glycerol, and placing the mixed solution into a water bath to react to obtain the metal-chelate retarder. The process of the present invention has a reliable principle, overcomes the defects of long production period, complex preparation and the like of the existing retarders, has the advantages of simple process operation, cheap and easily available raw materials, and short production period. The prepared retarder has wide temperature adaptation range and adjustable thickening time, is suitable for large-scale industrial production, and has a wide market application prospect.

The present invention relates to a process for preparing a metal-chelate retarder by a sol-gel method. The method comprises the following steps: weighing calcium nitrate tetrahydrate, aluminum nitrate nonahydrate and ferric nitrate nonahydrate according to a certain mass ratio and adding them into deionized water; placing the mixed solution on a magnetic stirrer and stirring the mixed solution evenly; adding citric acid monohydrate or gluconic acid, ethylene glycol or glycerol, and placing the mixed solution into a water bath to react to obtain the metal-chelate retarder. The process of the present invention has a reliable principle, overcomes the defects of long production period, complex preparation and the like of the existing retarders, has the advantages of simple process operation, cheap and easily available raw materials, and short production period. The prepared retarder has wide temperature adaptation range and adjustable thickening time, is suitable for large-scale industrial production, and has a wide market application prospect.

Disclosed is a sulfate corrosion-resistant concrete, a method for optimizing proportion and application thereof. The concrete is formed by mixing and stirring base stocks, aggregates, admixtures, external additives and water. The base stock of the concrete is 17.4-17.5 parts of Portland cement; the aggregates include 38.9 parts of basalt with aggregate size of 5-10 mm and 33.1-33.2 parts of basalt medium sand; the admixtures are 1.9-1.95 parts of silica fume or fly ash, and further including 0.23-0.24 part of polycarboxylate water reducer and 1.34-1.35 part of sulfate corrosion-resistant liquid preservative. Optimized proportion method: according to the corrosion characteristics of sulfate and corrosion environment parameters, determine the composition and proportion of basic samples and comparison samples, make and cure sample components, test the deep components of the samples, and obtain the optimal composition and proportion according to the test results.

A method for controlling the volume expansion of a hydraulically setting composition including steel making slag, the method including a step of adding a silica source to the composition. Furthermore, hydraulically setting compositions obtained by such methods and their uses.

A method for controlling the volume expansion of a hydraulically setting composition including steel making slag, the method including a step of adding a silica source to the composition. Furthermore, hydraulically setting compositions obtained by such methods and their uses.

A method of designing a cement slurry may include: (a) selecting at least a cement and concentration thereof, water and concentration thereof, and, optionally, at least one supplementary cementitious material and a concentration thereof, such that a cement slurry comprising the cement, the water, and, if present, the at least one supplementary cementitious material, meet a density requirement; (b) calculating a thickening time of the cement slurry using a thickening time model; (c) comparing the thickening time of the cement slurry to a thickening time requirement, wherein steps (a)-(c) are repeated if the thickening time of the cement slurry does not meet or exceed the thickening time requirement, wherein the selecting comprises selecting different concentrations and/or different chemical identities for the cement and/or the supplementary cementitious material than previously selected, or step (d) is performed if the thickening time of the cement slurry meets or exceeds the thickening time requirement; and preparing the cement slurry.

A method of designing a cement slurry may include: (a) selecting at least a cement and concentration thereof, water and concentration thereof, and, optionally, at least one supplementary cementitious material and a concentration thereof, such that a cement slurry comprising the cement, the water, and, if present, the at least one supplementary cementitious material, meet a density requirement; (b) calculating a thickening time of the cement slurry using a thickening time model; (c) comparing the thickening time of the cement slurry to a thickening time requirement, wherein steps (a)-(c) are repeated if the thickening time of the cement slurry does not meet or exceed the thickening time requirement, wherein the selecting comprises selecting different concentrations and/or different chemical identities for the cement and/or the supplementary cementitious material than previously selected, or step (d) is performed if the thickening time of the cement slurry meets or exceeds the thickening time requirement; and preparing the cement slurry.

Provided herein are compositions, methods, and systems related to cement blend composition comprising reactive vaterite cement and supplementary cementitious material (SCM) comprising aluminosilicate material.

Provided herein are compositions, methods, and systems related to cement blend composition comprising reactive vaterite cement and supplementary cementitious material (SCM) comprising aluminosilicate material.