Abstract: The present disclosure is directed to chemical additives for geopolymer cements that can improve the rheological properties of geopolymer cements. These chemical additives include sulfates and selenates of a specific formula as well as hydroxycarboxylic acid salts of Li, Na, and K including but not limited to glycolic, lactic, citric, mandelic tartaric, and malic acids. The chemical additives for geopolymer cements disclosed herein can facilitate the uniform mixing, increase the time mixtures can be transported, and improve the ability to place and finish concrete and mortars made with the geopolymer cements.

Abstract: The present disclosure is directed to chemical additives for geopolymer cements that can improve the rheological properties of geopolymer cements. These chemical additives include sulfates and selenates of a specific formula as well as hydroxycarboxylic acid salts of Li, Na, and K including but not limited to glycolic, lactic, citric, mandelic tartaric, and malic acids. The chemical additives for geopolymer cements disclosed herein can facilitate the uniform mixing, increase the time mixtures can be transported, and improve the ability to place and finish concrete and mortars made with the geopolymer cements.

Abstract: An active steel repassivator for the rehabilitation of chloride contaminated reinforced concrete structures and a method for the application of same is disclosed. The active steel repassivator is comprised of a continuous phase, a distributed phase, and/or an aqueous solution of an amine. The continuous phase, also known as the carrier phase, is selected from organic strong volatile bases, salts of weak volatile acids and a non-ionic surfactant. The distributed phase includes an anion containing vanadium in the +4 or +5 state of oxidation. The aqueous solution of the amine acts as a co-inhibitor in the composition.

Abstract: An active steel repassivator for the rehabilitation of chloride contaminated reinforced concrete structures and a method for the application of same is disclosed. The active steel repassivator is comprised of a continuous phase, a distributed phase, and/or an aqueous solution of an amine. The continuous phase, also known as the carrier phase, is selected from organic strong volatile bases, salts of weak volatile acids and a non-ionic surfactant. The distributed phase includes an anion containing vanadium in the +4 or +5 state of oxidation. The aqueous solution of the amine acts as a co-inhibitor in the composition.

Abstract: An active steel repassivator for the rehabilitation of chloride contaminated reinforced concrete structures and a method for the application of same is disclosed. The active steel repassivator is comprised of a continuous phase, a distributed phase, and/or an aqueous solution of an amine. The continuous phase, also known as the carrier phase, is selected from organic strong volatile bases, salts of weak volatile acids and a non-ionic surfactant. The distributed phase includes an anion containing vanadium in the +4 or +5 state of oxidation. The aqueous solution of the amine acts as a co-inhibitor in the composition.

Abstract: An active steel repassivator for the rehabilitation of chloride contaminated reinforced concrete structures and a method for the application of same is disclosed. The active steel repassivator is comprised of a continuous phase, a distributed phase, and/or an aqueous solution of an amine. The continuous phase, also known as the carrier phase, is selected from organic strong volatile bases, salts of weak volatile acids and a non-ionic surfactant. The distributed phase includes an anion containing vanadium in the +4 or +5 state of oxidation. The aqueous solution of the amine acts as a co-inhibitor in the composition.

Abstract: A corrosion inhibiting admixture for concrete is disclosed comprising a combination of organic (amines) and inorganic (nitrites) fractions that provide a synergistic effect when present at a specific ratio. Such a synergistic effect occurs when the amine:nitrite ratio (% by weight) is between 1.5 to 2.5 resulting in the admixture providing excellent corrosion inhibiting capabilities.

Abstract: A method of rapidly forming in place a cementitious structure comprising mixing a cement composition with an amount of a water soluble citrate effective to accelerate the setting of the cement in the presence of sufficient water for hydraulic setting of the cement, and delivering the resulting composition while fluid to the place for forming the cementitious structure.

Abstract: A cementitious composition comprising(a) a cementitious material;(b) a fly ash which has a calcium oxide content of from 15-45% by weight;(c) a hydroxycarboxylic acid; and(d) a water-soluble source of alkali metal ions.The compositions are useful as concretes, grouts and mortars.

Abstract: A cementitious composition comprising(A) 10-30 parts cementitious material;(B) 50-80 parts fly ash weight; and(C) 1.5-8 parts hydroxycarboxylic acid and/or salt thereof.

Abstract: A method of reclaiming leftover ready-mix concrete comprising the steps of:(1) retarding the hydration of the unused portion of concrete returned from a job site; and(2) after the desired retarded period adding a hydration acceleration agent to restore the concrete to a settable state.

Abstract: A method of reclaiming leftover ready-mix concrete comprising the steps of:(1) retarding the hydration of the unused portion of concrete returned from a job site; and(2) after the desired retarded period adding a hydration acceleration agent to restore the concrete to a settable state.