A hydraulic composition includes in relative parts by mass with respect to first Portland cement: 100 parts of a first Portland cement the particles of which have a D50 between 10 and 25 μm; from 25 to 76 parts of a second Portland cement the particles of which have a D50 between 0.5 and 6 μm; from 85 to 200 parts of sand; water; the water content being such that the hydraulic composition includes from 170 to 250 kg of water per cubic metre of hydraulic composition; the volume distribution of particle size of the first Portland cement and of the second Portland cement being further such that the ratio D50 of the first Portland cement/D50 of the second Portland cement is greater than 2.

A hydraulic composition includes in relative parts by mass with respect to first Portland cement: 100 parts of a first Portland cement the particles of which have a D50 between 10 and 25 μm; from 25 to 76 parts of a second Portland cement the particles of which have a D50 between 0.5 and 6 μm; from 85 to 200 parts of sand; water; the water content being such that the hydraulic composition includes from 170 to 250 kg of water per cubic metre of hydraulic composition; the volume distribution of particle size of the first Portland cement and of the second Portland cement being further such that the ratio D50 of the first Portland cement/D50 of the second Portland cement is greater than 2.

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

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

Methods of preparing engineered cementitious composite precursors include carbonating a fly ash comprising >about 25% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the fly ash to a first gas stream comprising carbon dioxide to form a carbonated fly ash. A steel slag is also carbonated that comprises >about 40% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the steel slag to a second gas stream comprising carbon dioxide to form a carbonated steel slag. The carbonated fly ash and the carbonated steel slag are suitable for use as engineered cementitious composite precursors in a bendable engineered cementitious composite composition that further comprises Portland cement, a polymeric fiber, and a superplasticizer.

Methods of preparing engineered cementitious composite precursors include carbonating a fly ash comprising >about 25% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the fly ash to a first gas stream comprising carbon dioxide to form a carbonated fly ash. A steel slag is also carbonated that comprises >about 40% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the steel slag to a second gas stream comprising carbon dioxide to form a carbonated steel slag. The carbonated fly ash and the carbonated steel slag are suitable for use as engineered cementitious composite precursors in a bendable engineered cementitious composite composition that further comprises Portland cement, a polymeric fiber, and a superplasticizer.

The invention relates to a method for producing supersulfated cement, wherein pozzolanic and hydraulic aluminosilicate components and a calcium-sulfate-alkaline activation complex are mixed together. The calcium-sulfate-alkaline activation complex is produced by carrying out the following successive steps: a first step of mixing 70% by weight of calcium sulfate and 30% by weight of alkaline components; and subsequently; a second step of thermodynamically activating, by hot quenching, the calcium-sulfate-alkaline activation complex; and subsequently; a third step of cold quenching, by rapid mixing, the activated calcium-sulfate-alkaline activation complex with the pozzolanic aluminosilicate components.

The invention relates to a method for producing supersulfated cement, wherein pozzolanic and hydraulic aluminosilicate components and a calcium-sulfate-alkaline activation complex are mixed together. The calcium-sulfate-alkaline activation complex is produced by carrying out the following successive steps: a first step of mixing 70% by weight of calcium sulfate and 30% by weight of alkaline components; and subsequently; a second step of thermodynamically activating, by hot quenching, the calcium-sulfate-alkaline activation complex; and subsequently; a third step of cold quenching, by rapid mixing, the activated calcium-sulfate-alkaline activation complex with the pozzolanic aluminosilicate components.

There is described a high-strength concrete generally having: about 100 parts by weight of cement; about 60 to about 360 parts by weight of fine aggregates; about 90 to about 230 parts by weight of mineral powder having a diameter D50 below 150 .Math.m; about 0.1 to about 25 parts by weight of superplasticizer; and about 20 to about 65 parts by weight of water, the high-strength concrete has a cement content less than about 500 kg/m.sup.3 and having a compressive strength after 28 curing days of about 55 MPa or greater.

Disclosed is a preparation method of a polycarboxylate water reducer having a regular sequence structure. The preparation method of the present invention comprises: performing Michael addition on polyethylene glycol ether acrylate macromonomer A and amino-containing carboxylic acid B for 5-12 hours, then cooling to 0° C., dropwise adding acryloyl chloride slowly and evenly, and further reacting for 12 hours at room temperature to obtain carboxyl-containing polyether macromonomer C; mixing the carboxyl-containing polyether macromonomer C, a small molecular RAFT reagent, an initiator, and water adequately; and holding the polymerization mass concentration at 30%-60% and heating to 60-80° C. in the atmosphere of N2 to react for 2-5 hours to obtain the polycarboxylate water reducer having a regular sequence structure.