A refractory composition including refractory aggregate, one or more matrix components, and silicate-coated set accelerator particles. The silicate-coated set accelerator particles can include one more of silicate-coated calcium hydroxide, magnesium hydroxide, calcium chloride, calcium carbonate, magnesium carbonate and calcium sulfate. Suitable silicate coatings include sodium silicate, potassium silicate, lithium silicate and mixtures thereof. A method of recovering an aged refractory composition, a settable composition and a method of manufacturing silicate-coated calcium hydroxide particles are also provided.

A method of cementing may include: measuring a feeding rate of water and a feeding rate of cement blend into a cement blender; calculating a cement retarder feeding rate and/or an accelerator feeding rate using a thickening time model, wherein the thickening time model uses at least a thickening time requirement, the feeding rate of water, and the feeding rate of cement blend, to calculate the cement retarder feeding rate and/or the accelerator feeding rate; introducing a cement retarder at the cement retarder feeding rate and/or an accelerator at the accelerator feeding rate into the cement blender; mixing at least the water, cement blend, and at least one of the cement retarder and/or the accelerator in the cement blender to provide a cement slurry; and placing the cement slurry in a wellbore.

A hydraulic composition for the construction of pavements, and in particular for the repair of pavements, includes a hydraulic binder including a cement, 0.18% to 0.35% of a superplasticiser, where the percentage is expressed by dry weight compared to the cement, and where the superplasticiser includes a branched polymer including at least one pendant chain, with a terminal function of the phosphonate or phosphate type, and 0.25% to 2% of a setting accelerator, where the percentage is expressed by dry weight compared to the cement, where the setting accelerator includes a calcium salt, where the hydraulic composition has a Water/Cement ratio higher than 0.38 and strictly less than 0.45.

A hydraulic composition for the construction of pavements, and in particular for the repair of pavements, includes a hydraulic binder including a cement, 0.18% to 0.35% of a superplasticiser, where the percentage is expressed by dry weight compared to the cement, and where the superplasticiser includes a branched polymer including at least one pendant chain, with a terminal function of the phosphonate or phosphate type, and 0.25% to 2% of a setting accelerator, where the percentage is expressed by dry weight compared to the cement, where the setting accelerator includes a calcium salt, where the hydraulic composition has a Water/Cement ratio higher than 0.38 and strictly less than 0.45.

Composite panels and methods of preparation are described herein. In some embodiments, the composite panel can include a first fiber reinforcement, a polyurethane composite having a first surface and a second surface opposite the first surface, wherein the first surface is in contact with the first fiber reinforcement; and a cementitious material adjacent the first fiber reinforcement opposite the polyurethane composite. The polyurethane composite can be formed from (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, (ii) one or more polyols, and (iii) a particulate filler. The fiber reinforcement can be formed from a woven or non-woven material, such as glass fibers. The composite panel can further include a material, such as a second fiber reinforcement and a cementitious layer, in contact with the second surface of the polyurethane composite. Articles comprising the composite panels are also disclosed.

Systems and methods for making gypsum board using a liquid gypsum set accelerator. Stucco and water are mixed to form a gypsum slurry, such as in a pin mixer. A gypsum set accelerator is mixed with a liquid medium to form a liquid gypsum set accelerator, such as in an eductor. The liquid gypsum set accelerator is added to the gypsum slurry, which is shaped to form the gypsum board.

Systems and methods for making gypsum board using a liquid gypsum set accelerator. Stucco and water are mixed to form a gypsum slurry, such as in a pin mixer. A gypsum set accelerator is mixed with a liquid medium to form a liquid gypsum set accelerator, such as in an eductor. The liquid gypsum set accelerator is added to the gypsum slurry, which is shaped to form the gypsum board.

A liquid accelerator composition for accelerating the setting reaction of calcium sulfate hemihydrate and water and methods of forming a liquid gypsum accelerator are provided. The liquid accelerator composition includes a liquid media in which calcium sulfate dihydrate is less than fully soluble and a ground product of a mill grinding of a mixture comprising calcium sulfate dihydrate.

A strengthening concrete admixture for the production of high-strength concrete products is provided. The strengthening concrete admixture comprises water; a set retarder comprising a salt of gluconic acid; one or more set accelerators; one or more hardening accelerators; and at least one stabilizing agent. Incorporation of the strengthening admixture in a cement mixture enhances both early and late age strength development and allows for sustainable and more energy efficient construction practices.

A building construction product with an electroconductive surface, the building construction product comprising a core with one or more surfaces covered by an electroconductive paper comprising carbon fibers, the electroconductive paper being attached to the one or more surfaces of the core. Methods and materials for producing the building construction products with an electroconductive surface and products and methods for shielding an area from electromagnetic waves.