A composition of a cement additive material to improve durability of cementitious structures, was disclosed. The cement additive composition includes an admixture of one or more of divalent magnesium metal silicates with capacity to act as a latent hydraulic binder in said composition activated by a hydration process under aqueous conditions, and in particular the divalent metal silicate is magnesium-dominated silicate, preferably comprising mineral groups of olivines, orthopyroxenes, amphiboles, and serpentines or mixtures thereof. The composition also includes chloride ions or brine.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

A composition of a cement additive material to improve durability of cementitious structures, was disclosed. The cement additive composition includes an admixture of one or more of divalent magnesium metal silicates with capacity to act as a latent hydraulic binder in said composition activated by a hydration process under aqueous conditions, and in particular the divalent metal silicate is magnesium-dominated silicate, preferably comprising mineral groups of olivines, orthopyroxenes, amphiboles, talc and serpentines or mixtures thereof. The composition also includes chloride ions or brine. Applications of the compositions are also disclosed, in particular to utilize a property of hydration as a major trigger for the latent hydraulic reaction of magnesium silicates, particularly for said olivines, when exposed to water and brines, in order to obtain a cementitious material becoming self healing.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component (e.g., slag cement) and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component (e.g., slag cement) and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

A composition of a cement additive material to improve durability of cementitious structures, was disclosed. The cement additive composition includes an admixture of one or more of divalent magnesium metal silicates with capacity to act as a latent hydraulic binder in said composition activated by a hydration process under aqueous conditions, and in particular the divalent metal silicate is magnesium-dominated silicate, preferably comprising mineral groups of olivines, orthopyroxenes, amphiboles, talc and serpentines or mixtures thereof. The composition also includes chloride ions or brine. Applications of the compositions are also disclosed, in particular to utilize a property of hydration as a major trigger for the latent hydraulic reaction of magnesium silicates, particularly for said olivines, when exposed to water and brines, in order to obtain a cementitious material becoming self healing.

A lime-based cement extender composition, and associated systems and methods are disclosed herein. In some embodiments, the lime-based cement extender composition includes 5-20% by weight lime particles, 40-50% by weight limestone particles, and 40-50% by weight pozzolan particles. Additionally or alternatively, the lime-based cement extender composition can comprise a calcium oxide concentration of 45-65%, a magnesium oxide concentration of 0.5-2%, an iron oxide concentration of 0.5-2.0%, an aluminum oxide concentration of 2-8%, a silicon dioxide concentration of 20-40%, a potassium oxide concentration of 20,000-30,000 ppm, and a sodium oxide concentration of 10,000-20,000 ppm. In some embodiments, the lime-based cement extender composition, or product, is combined with cement to produce a cement blend for use in the mining industry as mine backfill.

The present invention discloses a micro-nano composite hollow structured nanometer material-modified high-durability concrete material, and according to mass parts, its raw material formula is as follows: cobaltosic oxide, 1000-1500 parts; cement, 1000-1300 parts; dioctyl sebacate, 1000-1500 parts; water, 800-1200 parts; nanocarbon, 1200-1800 parts; nano calcium carbonate, 35-50 parts; sodium silicate, 10-20 parts; micro-nano structured calcium molybdate, 50-80 parts; dipentaerythritol, 60-90 parts; and dioctyl ester 30-60 parts. The present invention enables existing concrete to be improved effectively and stably in terms of shrinkage, cracking resistance and rapid hardening; the synthetic chemical functional material may lower a chloride ion diffusion coefficient of the concrete by more than 50%, cut down shrinkage by more than 30%, and reduce the cracking risk of concrete products by 50%.

Provided herein, inter alia, are compositions of cementitious products using recycled materials including natural pozzolans, manmade pozzolans, and/or desalinated waste products and seawater, the methods of preparing, and uses thereof.