The present invention belongs to the field of composite materials, particularly to an underwater non-dispersible quick-setting and rapid-hardening cement-based composite material and the preparation method and application thereof. The material consists of the following raw materials in percentage by weight: 32%-34% of silicate cement, 8.8%-9% of calcium aluminate, 5%-7% of magnesium oxide, 0.5%-2% of sulfur trioxide, 0.2%-0.3% of polycarboxylate high performance water-reducing agent, 0.3%-0.7% of flocculant, 0.05%-0.2% of setting accelerator, 0.05%-0.2% of air-entraining agent, 0.05%-0.3% of rust inhibitor, 26%-31% of fine aggregate, 13%-18% of coarse aggregate, and 8.4%-8.5% of water. The material can be used for rapid repair of cement buildings in water conservancy projects, the repair material can be quickly set and the initial strength can be guaranteed.

A method of cementing a wellbore comprises injecting into the wellbore a cement slurry comprising an aqueous carrier, a swellable nanoclay, and a solid delayed releasing divalent inorganic salt comprising calcined magnesium oxide, calcined calcium oxide, calcium magnesium polyphosphate, a borate, a nitride, a silicate, an agent having a cation of Ba.sup.2+, Sr.sup.2+, Fe.sup.2+, Ni.sup.2+, or a combination comprising at least one of the foregoing; and allowing the cement slurry to set.

A method of cementing a wellbore comprises injecting into the wellbore a cement slurry comprising an aqueous carrier, a swellable nanoclay, and a solid delayed releasing divalent inorganic salt comprising calcined magnesium oxide, calcined calcium oxide, calcium magnesium polyphosphate, a borate, a nitride, a silicate, an agent having a cation of Ba.sup.2+, Sr.sup.2+, Fe.sup.2+, Ni.sup.2+, or a combination comprising at least one of the foregoing; and allowing the cement slurry to set.

A method including introducing a well cementing composition into a wellbore, the cementing composition including a pumpable slurry of cement comprising a liquid anti-shrinkage additive including: an aqueous base fluid; a calcined magnesium oxide; and an anti-hydration agent; and allowing at least a portion of the cementing composition to harden. A liquid anti-shrinkage additive for cement including an aqueous base fluid, a calcined magnesium oxide, and an anti-hydration agent.

A method including introducing a well cementing composition into a wellbore, the cementing composition including a pumpable slurry of cement comprising a liquid anti-shrinkage additive including: an aqueous base fluid; a calcined magnesium oxide; and an anti-hydration agent; and allowing at least a portion of the cementing composition to harden. A liquid anti-shrinkage additive for cement including an aqueous base fluid, a calcined magnesium oxide, and an anti-hydration agent.

A geopolymer cement and a method of producing the same are provided. A geopolymer cement binder may be provided including a geopolymer precursor and magnesium oxide as an alkali activator. The geopolymer cement binder may be mixed with water using high shear mixing.

A geopolymer cement and a method of producing the same are provided. A geopolymer cement binder may be provided including a geopolymer precursor and magnesium oxide as an alkali activator. The geopolymer cement binder may be mixed with water using high shear mixing.

The present invention discloses an artificial stone slab, wherein the raw materials are mixed, pressed, and solidified, and the raw material comprises a main material and an auxiliary material. The main material, according to the total weight ratio of raw materials, comprises from about 20% to about 85% of particles containing hydroxide or metal oxide, from about 0% to about 50% of natural quartz, and from about 5% to about 25% of resin. The auxiliary material comprises a coupling agent and a curing agent, wherein the weight ratio of the coupling agent to the resin is from about 0.6:100 to about 2:100, and the weight ratio of the curing agent to the resin is from about 0.8:100 to about 1.2:100. The present invention also provides methods for manufacturing the aforesaid artificial stone slab. The present invention replaces natural quartz particles with particles containing hydroxide or metal oxide and ensures that the performance of the slab is up to standard, that the quality is more stable and easier to control, the decorative results are better, and finally, the mining of natural quartz is reduced by 10 times, achieving the objectives of greater environmental protection and lower costs. The resulting slab provides stable performance with good decorative results and thus saves resources and is conducive to environmental protection.

A method of producing a carbonated composite material is described that includes: providing a carbonatable cementitious material in particulate form; mixing the carbonatable cementitious material with water to produce a mix; forming a predetermined shape with the mix, wherein the predetermined shape has an initial pore structure containing an initial pore solution having a first pH; pre-conditioning the predetermined shape to remove a predetermined amount of the water from the predetermined shape to produce a pre-conditioned shape; carbonating the pre-conditioned shape in an environment comprising carbon dioxide to produce a modified pore structure containing a modified pore solution having and a second pH, wherein the difference between the first pH and the second pH is represented by a ΔpH, and the ΔpH is 1.0 or less, 0.75 or less, 0.5 or less, 0.25 or less, or about 0.0. A calcium silicate composition including solid components and liquid components having improved pore solution pH stability is also disclosed.

A method of producing a carbonated composite material is described that includes: providing a carbonatable cementitious material in particulate form; mixing the carbonatable cementitious material with water to produce a mix; forming a predetermined shape with the mix, wherein the predetermined shape has an initial pore structure containing an initial pore solution having a first pH; pre-conditioning the predetermined shape to remove a predetermined amount of the water from the predetermined shape to produce a pre-conditioned shape; carbonating the pre-conditioned shape in an environment comprising carbon dioxide to produce a modified pore structure containing a modified pore solution having and a second pH, wherein the difference between the first pH and the second pH is represented by a ΔpH, and the ΔpH is 1.0 or less, 0.75 or less, 0.5 or less, 0.25 or less, or about 0.0. A calcium silicate composition including solid components and liquid components having improved pore solution pH stability is also disclosed.