Admixture for cementitious compositions, cementitious compositions, cementitious structures and methods of making the same

Abstract

An aqueous admixture for inhibiting alkali-silica reactivity (ASR) in cementitious compositions includes an alkaline earth metal nitrate in an amount sufficient to inhibit or otherwise mitigate alkali-silica reactivity, a cement hydration retarder, and a solvent. Methods of making the admixture, cementitious compositions, and hardened cementitious structures are also disclosed.

Description

ADMIXTURE FOR CEMENTITIOUS COMPOSITIONS, CEMENTITIOUS COMPOSITIONS, CEMENTITIOUS STRUCTURES AND METHODS OF MAKING THE SAMETECHNICAL FIELD

[0001] The present disclosure is directed to an admixture for cementitious compositions, cementitious compositions comprising the admixture composition, a method of making the admixture composition, a method of making the cementitious composition, and a hardened cementitious structure prepared from the cementitious composition comprising the admixture composition. According to certain embodiments, the present disclosure is directed to an admixture for cementitious compositions for mitigating alkali-silica reaction in a cementitious composition, cementitious compositions comprising the admixture composition for mitigating alkali-silica reaction, a method of making the admixture composition for mitigating alkali-silica reaction, a method of making the cementitious composition with the admixture composition for mitigating alkali-silica reaction, and a hardened cementitious structure prepared from the cementitious composition comprising the admixture composition for mitigating alkali-silica reaction.BACKGROUND

[0002] Concrete compositions are prepared from a mixture of hydraulic cement (for example, Portland cement), aggregate and water. The aggregate used to make concrete compositions typically includes a blend of fine aggregate (such as sand), and coarse aggregate (such as limestone). Alkali -aggregate reaction (“AAR”) is a chemical reaction that occurs between the reactive components of the aggregate and the hydroxyl ions from the alkaline cement pore solution present in the concrete composition. Most of the most common alkali- aggregate reactions that occur between the aggregate and alkali hydroxide is the alkali-silica reaction (“ASR”) in which the hydroxyl ions from the alkaline cement pore solution react with reactive forms of silica from the aggregate. The result of the alkali-silica reaction is the formation of a hygroscopic alkali-silica gel that increases in volume by taking up water. As the volume of the alkali-silica gel increases it exerts an expansive pressure on the concrete resulting in cracking and ultimate failure of the hardened concrete form.

[0003] Many attempts have been made in the art to limit the expansion pressure caused by the formation of alkali-silica gels, and the overall the damaging effects of the alkali-silicareaction in hardened concrete. These attempts include the use of low alkali cement, non- reactive aggregate (for example, silica-free limestone aggregate), coated aggregates, pozzolans (for example, fly ash and silica fume), slag cement (for example, blast furnace slag), densified silica fume powder and lithium nitrate. Low alkali cement, certain types of fly ash, and slag cement suffer from limited availability.

[0004] What is still needed in the art is an effective admixture to mitigate the effect of the alkali-silica reaction in concrete that is based on components that are readily available and cost-effective, and that are more effective in mitigating the alkali-silica reaction in concrete as compared to the proposed solutions currently known in the art.SUMMARY OF ILLUSTRATIVE EMBODIMENTS

[0005] According to a first illustrative aspect, disclosed is an alkali-silica reaction mitigating admixture for cementitious compositions comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0006] According to a second illustrative aspect, disclosed is a cementitious composition comprising (i) a hydraulic cementitious binder, (ii) mineral aggregate, (iii) alkali- silica reaction mitigating admixture for cementitious compositions comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent, and (iv) water sufficient to hydrate the hydraulic cementitious binder.

[0007] According to a third illustrative aspect, disclosed is a method of making an admixture for cementitious compositions comprising combining together an alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0008] According to a fourth illustrative aspect, disclosed is a method for making a cementitious composition comprising mixing together (i) a hydraulic cementitious binder, (ii) mineral aggregate, (iii) an alkali-silica reaction mitigating admixture for cementitious compositions comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent, and (iv) water sufficient to hydrate the hydraulic cementitious binder.

[0009] According to a fifth illustrative aspect, disclosed is a method for making a hardened cementitious form or structure comprising (a) mixing together (i) a hydraulic cementitious binder, (ii) mineral aggregate, (iii) an alkali-silica reaction mitigating admixture for cementitious compositions comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent, (iv) water to form a cementitious composition, and (b) allowing the cementitious composition to harden.

[0010] According to a sixth illustrative aspect, disclosed is a method of mitigating alkali-silica reaction in cementitious compositions comprising adding an alkali-silica reaction mitigating admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent to the cementitious composition in amount sufficient to the mitigate alkali-silica reaction.

[0011] According to a seventh illustrative aspect, disclosed is the use of an admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent to prepare a cementitious composition in which alkali-silica reactions in the cementitious composition is mitigated.

[0012] According to an eighth illustrative aspect, disclosed is the use of an admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent in a cementitious composition in an amount sufficient to mitigate alkali-silica reactions in the cementitious composition.

[0013] According to a ninth illustrative aspect, disclosed is the use of an admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent to prepare a hardened cementitious form or structure from a cementitious composition in which alkali-silica reactions in the cementitious composition is mitigated by the admixture.

[0014] According to a tenth illustrative embodiment, provided is a building or construction material comprising an admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0015] According to a eleventh illustrative embodiment, provided is a building or construction material comprising hydratable cement, a mineral aggregate, and an admixture comprising alkaline earth metal nitrate, a cement hydration retarder, and solvent.BRIEF DESCRIPTION OF DRAWINGS

[0016] FIGURE 1 is a graph showing the effects of ASRI admixtures with desired retarding on cement hydration by calorimetry as compared to a control example containing only Ca(NO3)2.

[0017] FIGURE 2 is a graph showing the effects of ASRI admixtures with desired retarding with set retarder citric acid on cement hydration by calorimetry as compared to a control example containing only Ca(NO )2

[0018] FIGURE 3 is a graph showing the effects of ASRI admixtures with desired retarding with set retarder citric acid and ATMP on cement hydration by calorimetry as compared to a control example containing only Ca(NC>3)2.

[0019] FIGURE 4 is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with Hercules Type I / II cement and crushed limestone aggregate obtained from Brooks (Kentucky, USA) as measured by the Modified ASTM C 1567 Test Method.

[0020] FIGURE 5 is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with Hercules Type I / II cement and crushed limestone aggregate obtained from Brooks (Kentucky, USA) as measured by the Pipe Test Method.

[0021] FIGURE 6 is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with 25% borosilicate glass aggregate as measured by both the Modified ASTM 1567 C Test and the Pipe Test Method.

[0022] FIGURE 7 is a graph showing the alkali-silica reaction effects on mortar bar expansion prepared from cementitious mixes prepared with sand aggregate obtained from either Delta (Colorado, USA) or Knelsen (Alberta, Canada) as measured by the ASTM C 1567 Test Method.

[0023] FIGURE 8A is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with sand aggregate obtained from Delta and as measured by the Pipe Test Method.

[0024] FIGURE 8B is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with sand aggregate obtained from Delta and as measured by the Modified ASTM C 1567 Method.

[0025] FIGURE 9A is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with sand aggregate obtained from Knelsen and as measured by the Pipe Test Method.

[0026] FIGURE 9B is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixturecomprising Ca(NC>3)2 in a cementitious mixture prepared with sand aggregate obtained from Knelsen and as measured by the Modified ASTM C 1567 Method.

[0027] FIGURE 10A is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with natural sand aggregate obtained from Pearl River (Louisiana, USA) and as measured by the Pipe Test Method.

[0028] FIGURE 10B is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared natural sand aggregate obtained from Pearl River (Louisiana, USA) and as measured by the Modified ASTM C 1567 Method.

[0029] FIGURE 11A is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared with crushed limestone aggregate obtained from Smithland(Kentucky, USA) and as measured by the Pipe Test Method.

[0030] FIGURE 1 IB is a graph showing the alkali-silica reaction mitigating effects of various dosage amounts of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 in a cementitious mixture prepared crushed limestone aggregate obtained from Smithland (Kentucky, USA) and as measured by the Modified ASTM C 1567 Method.

[0031] FIG. 12 is a graph showing the effect of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 on the compressive strength of concrete prepared from a cementitious mixture having a medium alkali content.

[0032] FIG. 13 is a graph showing the effect of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 on the compressive strength of concrete prepared from a cementitious mixture having a low alkali content.

[0033] FIG. 14 is a graph showing the effect of the presently disclosed alkali-silica reactivity inhibiting admixture comprising Ca(NC>3)2 on the compressive strength of concrete prepared from a cementitious mixture having a high alkali content.DETAILED DESCRIPTION

[0034] Disclosed is an admixture that is effective in inhibiting or otherwise mitigating the alkali-silica reaction (ASR) reaction that occurs between the hydroxyl ions from the alkaline cement pore solution and the reactive silica components of the aggregate within a cementitious composition mixture. This admixture is referred to throughout this specification as the alkali-silica reactivity inhibiting admixture (“ASRI”).

[0035] The alkaline earth metal nitrate may be independently or separately added as a ASR-inhibiting component to a cementitious composition or as a component of a formulated ASRI admixture composition. According to certain illustrative embodiments, the ASRI for cementitious compositions comprises an alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0036] According to certain illustrative embodiments, the ASRI for cementitious compositions consists essentially of an alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0037] According to certain illustrative embodiments, the ASRI for cementitious compositions consists of an alkaline earth metal nitrate, a cement hydration retarder, and solvent.

[0038] The ASRI admixture for cementitious compositions comprises an effective amount of at least one alkaline earth metal nitrate to inhibit alkali-silica reactions in the cementitious composition, a cement hydration retarder, and a solvent. According to certain embodiments, the amount of the at least one alkaline earth metal nitrate included in the ASRI admixture is from about 40 to about 50 weight percent, or from about 41 to about 50 weight percent, or from about 42 to about 50 weight percent, or from about 43 to about 50 weight percent, or from about 44 to about 50 weight percent, or from about 45 to about 50 weight percent, or from about 46 to about 50 weight percent, or from about 47 to about 50 weight percent, or from about 48 to about 50 weight percent, or from about 49 to about 50 weight percent, or from about 42 to about 48 weigh percent, or from about 43 to about 48 weight percent, or from about 44 to about 48 weight percent, or from about 45 to about 48 weightpercent, or from about 46 to about 48 weight percent, or from about 42 to about 46 weight percent, or from about 43 to about 46 weight percent, or from about 44 to about 46 weight percent, or from about 42 to about 45 weight percent, or from about 43 to about 45 weight percent, or from about 44 to about 45 weight percent, or from about 43 to about 44 weight percent, or from any other amount in the range from about 40 to about 50 weight percent.

[0039] The ASRI admixture for cementitious compositions comprises at least one cement hydration retarder. According to certain embodiments, the amount of the at least one cement hydration retarder in the ASRI admixture is 5 weight percent or less, or 4.5 weight percent or less, or 4 weight percent or less, or 3.5 weight percent or less, or 3 weight percent or less, or 2.5 weight percent or less, or 2 weight percent or less, or 1.9 weight percent or less, or 1.8 weight percent or less, or 1.7 weight percent or less, or 1.6 weight percent or less, or 1.5 weight percent or less, or 1.4 weight percent or less, or 1.3 weight percent or less, or 1.2 weight percent or less, or 1.1 weight percent or less, or 1 weight percent or less, or 0.9 weight percent or less, or 0.8 weight percent or less, or 0.7 weight percent or less, or 0.6 weight percent or less, or 0.5 weight percent or less, or 0.4 weight percent or less, or 0.3 weight percent or less, or any other amount between 0.3 weight percent 10 weight percent, based on the total weight of the ASRI admixture.

[0040] The ASRI admixture for cementitious compositions comprises a solvent. According to certain embodiments, the amount of solvent in the ASRI admixture 10 weight percent or less, or 9.5 weight percent or less, or 9 weight percent or less, or 8.5 weight percent or less, or 8 weight percent or less, or 7.5 weight percent or less, or 7 weight percent or less, or 6.5 weight percent or less, or 6 weight percent or less, or 5.5 weight percent or less, or 5 weight percent or less, or 4.5 weight percent or less, or 4 weight percent or less, or 3.5 weight percent or less, or 3 weight percent or less, or 2.5 weight percent or less, or 2 weight percent or less, or 1.75 weight percent or less, or 1.5 weight percent or less, or 1 weight percent or less, or 0.75 weight percent or less, or 0.5 weight percent or less, or any other amount between 0.5 weight percent 10 weight percent, based on the total weight of the ASRI admixture.

[0041] The at least one alkaline earth metal nitrate included in the ASRI admixture may be selected from calcium nitrate (CafNCh ) and / or magnesium nitrate (MgfNCh ). According to certain illustrative embodiments, the alkaline earth metal nitrate comprising the ASRI admixture is calcium nitrate.

[0042] The at least one cement hydration retarder included in the ASRI admixture may be selected from any set retarder known to retard, delay, or slow the rate of setting of cement hydration. Without limitation, and only by way of illustration, suitable set retarders include lignosulfonates, hydroxylated carboxylic acids, lignin, borax (sodium tetraborate), boric acid, citric acid, gluconic acid, tartaric acid, and other organic acids and their corresponding salts, phosphonic acids such as aminotris(methylenephosphonic acid), phosphonates, certain carbohydrates and mixtures thereof may be used as the at least one set retarder. According to certain illustrative embodiments, at least one cement hydration retarder included in the ASRI admixture comprises a salt of gluconic acid and a phosphonic acid, optionally, wherein the amount of the salt of gluconic acid present in the ASRI admixture is equal to or greater than the amount of the phosphonic acid present in the ASRI admixture. According to other illustrative embodiments, at least one cement hydration retarder included in the ASRI admixture comprises gluconic acid, a salt of gluconic acid, and a phosphonic acid, optionally, wherein the amount of the gluconic acid present in the ASRI admixture is equal to or greater than the amount of the salt of gluconic acid present in the ASRI admixture and equal to or greater than the amount of the phosphonic acid present in the ASRI admixture, optionally, wherein the amount of the salt of gluconic acid present in the ASRI admixture is less than the amount of the gluconic acid present in the ASRI admixture and greater than the amount of the phosphonic acid present in the ASRI admixture. According to certain illustrative embodiments, at least one cement hydration retarder included in the ASRI admixture comprises gluconic acid and a phosphonic acid, optionally, wherein the amount of the gluconic acid present in the ASRI admixture is equal to or greater than the amount of the phosphonic acid present in the ASRI admixture. According to certain illustrative embodiments, at least one cement hydration retarder included in the ASRI admixture comprises an organic acid other than gluconic acid and a phosphonic acid, optionally, wherein the amount of the organic acid present in the ASRI admixture is equal to or greater than the amount of the phosphonic acid present in the ASRI admixture. According to certain illustrative embodiments, at least one cement hydration retarder included in the ASRI admixture comprises a salt of gluconic acid, an organic acid and a phosphonic acid, optionally, wherein the amount of the salt of gluconic acid present in the ASRI admixture is equal to or greater than the amount of the organic acid present in the ASRI admixture and equal to or greater than the amount of the phosphonic acid present in the ASRI admixture, optionally, wherein the amount of the salt of gluconic acid present in the ASRI admixture is equal to or greater than the amount of the organic acid present in the ASRIadmixture and equal to or greater than the amount of the phosphonic acid present in the ASRI admixture, and the amount of the organic acid is greater than the amount of the phosphonic acid.

[0043] The ASRI includes at least one solvent for preparing a liquid ASRI admixture for addition to a cementitious composition. Without limitation, and only by way of illustration, suitable solvents used to prepare the ASRI admixture comprise oxygenated solvents, such as water. The use of water as the solvent for the ASRI admixture results in an aqueous admixture that may be easily incorporated into a cementitious composition.

[0044] According to certain embodiments, also disclosed is a method of making an ASRI admixture for cementitious compositions. The method of making the admixture comprises combining together an alkali-silica reactivity inhibiting additive, such as an alkaline earth metal nitrate, a cement hydration retarder, and water to form an aqueous admixture.

[0045] According to certain embodiments, also disclosed is a cementitious composition comprising a hydraulic cementitious binder, optionally at least one mineral aggregate, the disclosed ASRI admixture in an amount effective to inhibit alkali-silica reactions, and additional water for hydration of the cementitious binder.

[0046] According to certain embodiments, also disclosed is a cementitious composition comprising a hydraulic cementitious binder, at least one coarse mineral aggregate, the disclosed ASRI admixture in an amount effective to inhibit alkali-silica reactions, and additional water for hydration of the cementitious binder.

[0047] According to certain embodiments, also disclosed is a cementitious composition comprising a hydraulic cementitious binder, at least one fine mineral aggregate, the disclosed ASRI admixture in an amount effective to inhibit alkali-silica reactions, and additional water for hydration of the cementitious binder.

[0048] According to certain embodiments, also disclosed is a cementitious composition comprising a hydraulic cementitious binder, at least one coarse aggregate, at least one fine mineral aggregate, the disclosed ASRI admixture in an amount effective to inhibit alkali-silica reactions, and additional water for hydration of the cementitious binder.

[0049] As used herein, the term cement refers to any hydraulic cement. Hydraulic cements are materials that set and harden in the presence of water. Suitable non-limiting examples of hydraulic cements include Portland cement, masonry cement, alumina cement, refractory cement, magnesia cements, such as a magnesium phosphate cement, a magnesium potassium phosphate cement, calcium aluminate cement, calcium sulfoaluminate cement, calcium sulfate hemi-hydrate cement, oil well cement, ground granulated blast furnace slag, natural cement, hydraulic hydrated lime, and mixtures thereof. Portland cement, as used in the trade, means a hydraulic cement produced by pulverizing clinker, comprising of hydraulic calcium silicates, calcium aluminates, and calcium ferroaluminates, with one or more of the forms of calcium sulfate as an interground addition. Portland cements according to ASTM Cl 50 are classified as types I, II, III, IV, or V. According to certain illustrative embodiments, the cement may be a low alkali content cement. According to certain illustrative embodiments, the cement may be a medium alkali content cement. According to certain illustrative embodiments, the cement may be a high alkali content cement.

[0050] The amount of the liquid ASRI admixture added to the cementitious compositions should be sufficient to provide a dosage of the at least one alkaline earth metal nitrate sufficient to at least partially inhibit or reduce alkali-silica reactivity in the cementitious composition. The term “at least partially inhibit or reduce alkali-silica reactivity” means that alkali-silica reactions in a cementitious composition containing ASRI admixture are less as compared to the same cementitious composition without the ASRI admixture. According to certain illustrative embodiments, the amount of the ASRI admixture added to a cementitious composition provide a dosage of the at least one alkaline earth metal nitrate sufficient to at least partially inhibit or reduce alkali-silica reactivity in the cementitious composition which is in the range of about 2 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 3 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 4 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 5 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 6 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 7 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 8 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than9 to about 10 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 2 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 3 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 4 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 5 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 6 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 7 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 2 to about 6 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 3 to about 6 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 4 to about 6 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 5 to about 6 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 2 to about 5 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 3 to about 5 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 4 to about 5 percent of the at least one alkaline earth metal nitrate by weight of cement, or in the range of greater than 3 to about 8 percent of the at least one alkaline earth metal nitrate by weight of cement, or in any other amount in the range of about 2 to about10 percent of the at least one alkaline earth metal nitrate by weight of cement.

[0051] The cementitious composition may also include any other cement admixture or additive including, air entraining agents, air detraining agents, corrosion inhibitors, dispersants, pigments, plasticizers, super plasticizers, wetting agents, water repellants, fibers, dampproofmg agent, gas formers, permeability reducers, pumping aids, fungicidal admixtures, germicidal admixtures, insecticidal admixtures, bonding admixtures, strength enhancing agents, shrinkage reducing agents, aggregates, pozzolans, and mixtures thereof.

[0052] The term dispersant as used throughout this specification includes, among others, poly carboxylate dispersants. Polycarboxylate dispersants refer to dispersants having a carbon backbone with pendant side chains, wherein at least a portion of the side chains are attached to the backbone through a carboxyl group, an ether group, an amide group or an imide group. The term dispersant is also meant to include those chemicals that also function as a plasticizer, water reducers, high range water reducers, fluidizer, antiflocculating agent, orsuperplasticizer for cementitious compositions. Without limitation, and only by way of illustration, suitable dispersants include polycarboxylates (including polycarboxylate ethers), lignosulfonates (calcium lignosulfonates, sodium lignosulfonates and the like), salts of sulfonated naphthalene sulfonate condensates, salts of sulfonated melamine sulfonate condensates, beta naphthalene sulfonates, sulfonated melamine formaldehyde condensates, naphthalene sulfonate formaldehyde condensate resins, polyaspartates, oligomeric dispersants and mixtures thereof.

[0053] The term air entrainer includes any chemical that will entrain air in cementitious compositions. Air entrainers can also reduce the surface tension of a composition at low concentration. Air-entraining admixtures are used to purposely entrain microscopic air bubbles into concrete. Air-entrainment dramatically improves the durability of concrete exposed to moisture during cycles of freezing and thawing. In addition, entrained air greatly improves a concrete's resistance to surface scaling caused by chemical deicers. Air entrainment also increases the workability of fresh concrete while eliminating or reducing segregation and bleeding. Without limitation, and only by way of illustration, suitable air entrainers include salts of wood resin, certain synthetic detergents, salts of sulfonated lignin, salts of petroleum acids, salts of proteinaceous material, fatty and resinous acids and their salts, alkylbenzene sulfonates, salts of sulfonated hydrocarbons and mixtures thereof.

[0054] Air detrainers are used to decrease the air content in the mixture of concrete. Without limitation, and only by way of illustration, suitable air detainers include tributyl phosphate, dibutyl phthalate, octyl alcohol, water-insoluble esters of carbonic and boric acid, silicones and mixtures thereof.

[0055] Bonding agents may be added to Portland cement compositions to increase the bond strength between old and new concrete. Without limitation, and only by way of illustration, suitable bonding agents include organic materials such as rubber, polyvinyl chloride, polyvinyl acetate, acrylics, styrene butadiene copolymers, other powdered polymers and mixtures thereof.

[0056] Corrosion inhibitors may be included in the cementitious compositions to protect embedded reinforcing steel from corrosion. The high alkaline nature of the concrete causes a passive and non-corroding protective oxide fdm to form on the steel. However,carbonation or the presence of chloride ions from deicers or seawater can destroy or penetrate the fdm and result in corrosion. Corrosion-inhibiting admixtures chemically mitigate this corrosion reaction. Without limitation, and only by way of illustration, suitable corrosion inhibitors include sodium nitrite, sodium benzoate, certain phosphates or fluorosilicates, fluoroaluminates, amines, and mixtures thereof.

[0057] Dampproofmg agents may be included in the cementitious compositions reduce the permeability of concrete that have low cement contents, high water-cement ratios, or a deficiency of fines in the aggregate. The dampproofmg agents retard moisture penetration into dry concrete. Without limitation, and only by way of illustrative, dampproofmg agent include certain soaps, stearates, petroleum products and mixtures thereof.

[0058] Gas formers, or gas-forming agents, may be included in cementitious compositions to cause a slight expansion prior to hardening. The amount of expansion is dependent upon the amount of gas-forming material used and the temperature of the fresh cementitious mixture. Without limitation, and only by way of illustration, suitable gas-forming agent include aluminum powder, resin soap, vegetable or animal glue, saponin or hydrolyzed protein and mixtures thereof.

[0059] Reinforcing fibers may be distributed throughout an unhardened concrete mixture. Upon hardening of the mixture, this concrete is referred to as fiber-reinforced concrete. The cementitious mixture may include inorganic fibers, organic fibers, and blends of these types of fibers. Without limitation and only by way of illustration, suitable reinforcing fibers that may be included in the zirconium fibers, metal fibers, metal alloy fibers (eg, steel fibers), fiberglass, polyethylene, polypropylene, fibers nylon fibers, polyester fibers, rayon fibers, high-strength aramid fibers and mixtures thereof.

[0060] Antimicrobial admixtures may be included in the cementitious compositions to control microbial growth, such as bacterial growth, on or in the final hardened cementitious form or structure.

[0061] Fungicidal admixtures may be included in the cementitious compositions to control microbial growth, such as fungal growth, on or in the final hardened cementitious form or structure.

[0062] Insecticidal admixtures may be included in the cementitious compositions to protect the final hardened cementitious form or structure from damage by insects.

[0063] According to certain illustrative embodiments, the cementitious compositions exhibits a slump value of 14 cm or greater, or a slump value of 15 cm or greater, or a slump value of 16 cm or greater, or a slump value of 17 cm or greater, or a slump value of 18 cm or greater, or a slump value of 19 cm or greater, or a slump value of 20 cm or greater, or a slump value of 21 cm or greater, or a slump value of 22 cm or greater, or a slump value of 23 cm or greater, or a slump value of 24 cm or greater, or a slump value of 25 cm or greater, as determined by ASTM C143.

[0064] According to certain illustrative embodiments, the cementitious compositions exhibit 2 percent or less by volume of entrained air as determined by ASTM C231. According to certain embodiments, the cementitious compositions exhibits 1.9 percent or less by volume of entrained air, or 1.8 percent by volume or less, or 1.7 percent by volume or less, or 1.6 percent by volume or less, or 1.5 percent by volume or less, or 1.4 percent by volume or less, 1.3 percent by volume or less, or 1.2 percent by volume or less, or 1.1 percent by volume or less, or 1.0 percent by volume or less.

[0065] According to certain illustrative embodiments, the cementitious compositions exhibits a 1 Day compressive strength greater than 15 Mpa (2175 psi), or greater than 16 Mpa (2320 psi), or greater than 17 Mpa (2465 psi), or greater than 18 Mpa (2611 psi), or greater than 19 Mpa (2756 psi), or greater than 20 Mpa (2900 psi) as determined by ASTM C39. The inclusion of an alkali metal nitrate into a cementitious composition increases 1-day compressive strength of a concrete prepared from the cementitious composition as compared to the same cementitious composition without the inclusion of the alkali metal nitrate.

[0066] According to certain illustrative embodiments, the cementitious compositions exhibits a 7 Day compressive strength greater than 35 Mpa (5076 psi), or greater than 36 Mpa (5221 psi), or greater than 37 Mpa (5366 psi), or greater than 38 Mpa (5511 psi), or greater than 39 Mpa (5656 psi), or greater than 40 Mpa (5801 psi), or greater than 41 Mpa (5946 psi), or greater than 42 Mpa (6092 psi), or greater than 43 Mpa (6237 psi), as determined by ASTM C39. The inclusion of an alkali metal nitrate into a cementitious composition increases 7-daycompressive strength of a concrete prepared from the cementitious composition as compared to the same cementitious composition without the inclusion of the alkali metal nitrate.

[0067] According to certain illustrative embodiments, the cementitious compositions exhibits a 28 Day compressive strength greater than 43 Mpa (6237 psi), or greater than 44 Mpa (6382 psi), or greater than 45 Mpa (6527 psi), or greater than 46 Mpa (6672 psi), or greater than 47 Mpa (6817 psi), or greater than 48 Mpa (6962 psi), or greater than 49 Mpa (7107 psi), or greater than 50 Mpa (5272 psi), or greater than 51 Mpa (7397 psi), or greater than 52 Mpa (7542 psi), or greater than 53 Mpa (7687 psi), or greater than 54 Mpa (7832 psi), or greater than 55 Mpa (7978 psi), as determined by ASTM C39. The inclusion of an alkali metal nitrate into a cementitious composition increases 28-day compressive strength of a concrete prepared from the cementitious composition as compared to the same cementitious composition without the inclusion of the alkali metal nitrate.

[0068] According to certain embodiments, a concrete prepared from a cementitious composition including the ASR-inhibiting additive or the ASRI admixture exhibits a 10 percent or greater improvement in 1-day, 7-day, and 28-day compressive strength, or 15 percent or greater improvement in such compressive strength, or 20 percent or greater improvement in such compressive strength, or 25 percent or greater improvement in such compressive strength, 30 percent or greater improvement in such compressive strength, 35 percent or greater improvement in such compressive strength, or 40 percent or greater improvement in such compressive strength, or 45 percent or greater improvement in such compressive strength, or 50 percent or greater improvement in such compressive strength, or any percent increase of such compressive strength within the range of 20 percent to 50 percent. According to certain embodiments, a concrete prepared from a low alkali content cementitious composition including the ASR-inhibiting additive or the ASRI admixture exhibits an increase in 1-day, 7- day and 28-day compressive strength of about 20 percent to about 40 percent as compared to a concrete prepared from a low alkali content cementitious composition including the ASR- inhibiting additive or the ASRI admixture without the ASR-inhibiting additive or the ASRI admixture. According to certain embodiments, a concrete prepared from a medium alkali content cementitious composition including the ASR-inhibiting additive or the ASRI admixture exhibits an increase in 1-day, 7-day and 28-day compressive strength of about 10 percent to about 45 percent as compared to a concrete prepared from a medium alkali content cementitious composition including the ASR-inhibiting additive or the ASRI admixturewithout the ASR-inhibiting additive or the ASRI admixture. According to certain embodiments, a concrete prepared from a high alkali content cementitious composition including the ASR-inhibiting additive or the ASRI admixture exhibits an increase in 7-day and 28-day compressive strength of about 25 percent to about 35 percent as compared to a concrete prepared from a high alkali content cementitious composition including the ASR-inhibiting additive or the ASRI admixture without the ASR-inhibiting additive or the ASRI admixture.

[0069] According to certain embodiments, disclosed is a method for making a cementitious composition. The method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more mineral aggregates, an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0070] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more mineral aggregates, an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0071] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more mineral aggregates, an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0072] According to certain embodiments, disclosed is a method for making a cementitious composition. The method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more coarse mineral aggregates, an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0073] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more coarsemineral aggregates, an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0074] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more coarse mineral aggregates, an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0075] According to certain embodiments, disclosed is a method for making a cementitious composition. The method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more fine mineral aggregates, an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0076] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more fine mineral aggregates, an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0077] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, one or more fine mineral aggregates, an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0078] According to certain embodiments, disclosed is a method for making a cementitious composition. The method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, coarse and fine mineral aggregates, an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and solvent,and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0079] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, coarse and fine mineral aggregates, an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0080] According to certain embodiments, the method of making the cementitious composition comprises mixing together a hydraulic cementitious binder, coarse and fine mineral aggregates, an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and solvent, and water in a sufficient amount to hydrate the hydraulic cementitious binder in the composition.

[0081] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) one or more mineral aggregates, (iii) an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0082] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) one or more mineral aggregates, (iii) an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0083] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) one or more mineral aggregates, (iii) an admixture consisting of analkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0084] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse mineral aggregate, (iii) an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0085] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse mineral aggregate, (iii) an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0086] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse mineral aggregate, (iii) an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0087] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) fine mineral aggregate, (iii) an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is thenplaced at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0088] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) fine mineral aggregate, (iii) an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0089] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) fine mineral aggregate, (iii) an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0090] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse and fine mineral aggregate, (iii) an admixture comprising an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0091] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse and fine mineral aggregate, (iii) an admixture consisting essentially of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0092] According to certain embodiments, disclosed is a method for making a hardened cementitious form or structure. The method comprises mixing together (i) a hydraulic cementitious binder, (ii) coarse and fine mineral aggregate, (iii) an admixture consisting of an alkaline earth metal nitrate, a cement hydration retarder, and a solvent, and (iv) water to hydrate the hydraulic cementitious binder to form a cementitious composition. The cementitious composition is then placed at a selected location and to cure or harden to form a hardened cementitious form or structure.

[0093] The terms “comprises,” “comprising,” “has,” “having,” “includes,” “including,” “contains,” “containing,” or any other variation are open-ended and are intended to cover a non-exclusive inclusion of elements, such that an article, apparatus, compound, composition, combination, method, or process that “comprises,” “has,” or “includes,” or “contains” a recited list of elements does not include only those elements but may include other elements not expressly listed, recited or written in the specification or claims. An element or feature proceeded by the language “comprises . . .a,” “contains . . . a,” “has . . . a,” or “includes . . .a” does not, without more constraints, preclude the existence or inclusion of additional elements or features in the article, apparatus, compound, composition, combination, method, or process that comprises, contains, has, or includes the element or feature.

[0094] The terms “a” and “an” are defined as one or more unless expressly stated otherwise or constrained by other language herein. An element or feature proceeded by “a” or “an” may be interpreted as one of the recited element or feature, or more than one of the element or feature.

[0095] The terms “about,” “approximately,” “essentially,” “substantially,” any other version thereof, or any other similar relative term, or similar term of approximation, are defined as being close to as understood by one having ordinary skill in the art. By way of non-limiting, illustrative embodiments, these terms are defined to be within 10% of recited value, or defined to be within 5% of a recited value, or defined to be within 4% of a recited value, or defined to be within 3% of a recited value, or defined to be within 2% of a recited value, or defined to be within 1% of a recited value, of defined to be within 0.75% of a recited value, or defined to be within 0.5% of a recited value, or defined to be within 0.25% of a recited value, or defined to be within 0. 1% of a recited value.

[0096] It should be understood that when an amount in weight percent is described in the present disclosure, it is intended that any and every amount within the range, including the end points, is to be considered as having been expressly disclosed. For example, the disclosure of "a range of from about 1 to about 100" is to be read as indicating each and every possible number along the continuum between about 1 and about 100. It is to be understood that the inventors appreciate and understand that any and all data points within the range are to be considered to have been specified, and that the inventors have possession of the entire range and all points within the range.EXAMPLES

[0097] The following examples are set forth merely to further illustrate the admixture compositions and methods of making the ASR-mitigating admixture, cementitious compositions and method of the making the admixture and cementitious composition. The illustrative examples should not be construed as limiting the admixture composition, the cementitious composition incorporating the admixture composition, or the methods of making or using the admixture composition in any manner.

[0098] Preparation of ASRI Admixture

[0099] Illustrative embodiments of the ASRI admixture are set forth in Table 1 below:Table 1ATMP = aminotris(methylene phosphonic acid)

[0100] Cementitious Compositions Containing ASRI Admixture

[0101] Table 2 below shows several cementitious compositions prepared with illustrative embodiments of the ASRI admixture:Table 2Cementitious Composition with ASRI Admixture

[0102] Tables 3 and 4 below shows several cementitious compositions prepared with illustrative embodiments of the ASRI admixture:Table 3Cementitious Composition with ASRI AdmixtureTable 3 (con’t)Cementitious Composition with ASRI Admixture

[0103] Table 4 below shows several cementitious compositions prepared with an illustrative embodiment of the ASRI admixture (Admixture 15) and using a medium alkali cement (Holcim cement):Table 4Cementitious Composition with ASRI Admixture

[0104] In addition to inhibiting alkali-silica reactivity in a cementitious composition, the graph of FIG. 1 also shows that the inclusion of the ASRI admixture in a cementitious composition provides a desired retarding or delay in cement hydration. FIG 1 depicts the rate of heat evolution (ie, the heat of hydration) and hydration time of cementitious compositions without Ca(NO )2 or the ASRI admixture (Control), Ca(NC>3)2 dosed at 4.5% by cement weight (cwt.), and the ASRI admixture dosed at 4.5% as Ca(NOs)2 by cement weight (cwt.). The peak of the heat of hydration for the sample dosed with 4.5% by cement weight (cwt.) of Ca(NC>3)2 occurs at approximately 3 hours. The peak of the heat of hydration for the Control and inventive ASRI Admixture 15 are about 8 hours . These results demonstrate that the inclusion of the ASRI admixture in a cementitious composition inhibits alkali-silica reactivity and provides cement hydration rates similar to the control cementitious composition without Ca(NC>3)2.

[0105] In addition to inhibiting alkali-silica reactivity in a cementitious composition, the graph of FIG. 2 also shows that the inclusion of the ASRI admixture in a cementitious composition provides a desired retarding or delay in cement hydration. FIG 2 depicts the rate of heat evolution (ie, the heat of hydration) and hydration time of cementitious compositions without Ca(NC>3)2 (Control) or the ASRI admixture, Ca(NC>3)2 dosed at 4.5% by cement weight (cwt.), and embodiments of the ASRI admixture dosed at 4.5% as Ca(NC>3)2 by cement weight (cwt.) (Admixtures 8, 9 and 10). The peak of the heat of hydration for the sample dosed with 4.5% by cement weight (cwt.) of Ca(NC>3)2 occurs at approximately 6 hours. The peak of the heat of hydration for the Control sample was about 7.5 hours. The peak of the heat of hydration for the inventive samples were about 10 hours (Admixture 10), about 11 hours (Admixture 9), and about 13 hours (Admixture 8). These results demonstrate that the inclusion of the ASRI admixture in a cementitious composition inhibits alkali-silica reactivity and provides cement hydration rates similar to the control cementitious composition without Ca(NC>3)2.

[0106] In addition to inhibiting alkali-silica reactivity in a cementitious composition, the graph of FIG. 3 also shows that the inclusion of the ASRI admixture in a cementitious composition provides a desired retarding or delay in cement hydration. FIG 3 depicts the rate of heat evolution (ie, the heat of hydration) and hydration time of cementitious compositions without Ca(NC>3)2 or the ASRI admixture (Control), Ca(NC>3)2 dosed at 4.5% by cement weight (cwt.), and illustrative embodiments of the ASRI admixture dosed at 4.5% as Ca(NC>3)2 by cement weight (cwt.). The peak of the heat of hydration for the sample dosed with 4.5% by cement weight (cwt.) of Ca(NC>3)2 occurs at approximately 6 hours. The peak of the heat of hydration for the Control is about 7.5 hours. The peak of the heat of hydration for the samples dosed with the ASRI admixtures were about 9 hours (Admixture 19) and about 11 hours (Admixture 18). These results demonstrate that the inclusion of the ASRI admixture in a cementitious composition inhibits alkali-silica reactivity and provides cement hydration rates similar to the control cementitious composition without Ca(NC>3)2.

[0107] FIG. 12 shows the 1-day, 7-day and 28-day compressive strengths of concretes prepared with the cementitious mixtures of comparative Mix 22 and inventive Mixes 23-29 of Table 4 above. The results in FIG. 12 show that the ASRI admixture dosed at 4.5% Ca(NOs)2 by weight of cement increases the 1-day, 7-day and 28-day compressive strength of concrete. The 1-day compressive strength of a concrete prepared with inventive cementitious Mix 29 isincreased by 12.7 % as compared to the 1-day compressive strength of a concrete prepared with comparative cementitious Mix 22. The 7-day compressive strength of a concrete prepared with inventive cementitious Mix 29 is increased by 19.1% as compared to the 7-day compressive strength of a concrete prepared with comparative cementitious Mix 22. The 28-day compressive strength of a concrete prepared with inventive cementitious Mix 29 is increased by 42% as compared to the 28-day compressive strength of a concrete prepared with comparative cementitious Mix 22. These results show that the use of the ASRI at a dosage of 4.5% Ca(NOs)2 by weight of cement increases both the early and late compressive strengths of concrete compositions.

[0108] Table 5 below shows several cementitious compositions prepared with an illustrative embodiment of the ASRI admixture (Admixture 15) and using a high alkali cement (Hercules Type I / II cement):Table 5Cementitious Composition with ASRI Admixture

[0109] FIG. 14 shows the 1-day, 7-day and 28-day compressive strengths of concretes prepared with the cementitious mixtures of comparative Mix 30 and inventive Mixes 31-38 of Table 5 above. The results in FIG. 14 show that the ASRI admixture dosed at 4.5% Ca(NOs)2 by weight of cement increases the 1-day, 7-day and 28-day compressive strength of concrete. The 7-day compressive strength of a concrete prepared with inventive cementitious Mix 38 is increased by 29.6% as compared to the 7-day compressive strength of a concrete prepared with comparative cementitious Mix 30. The 28-day compressive strength of a concrete prepared with inventive cementitious Mix 38 is increased by 34% as compared to the 28-day compressive strength of a concrete prepared with comparative cementitious Mix 30.

[0110] Table 6 below shows several cementitious compositions prepared with an illustrative embodiment of the ASRI admixture (Admixture 15) and using a low alkali cement (CalPortland II / V cement):Table 6Cementitious Composition with ASRI Admixture

[0111] FIG. 13 shows the 1-day, 7-day and 28-day compressive strengths of concretes prepared with the cementitious mixtures of comparative Mix 39 and inventive Mixes 40-47 of Table 6 above. The results in FIG. 13 show that the ASRI admixture dosed at 4.5% Ca(NC>3)2 by weight of cement increases the 1-day, 7-day and 28-day compressive strength of concrete. The 1-day compressive strength of a concrete prepared with inventive cementitious Mix 47 is increased by 20 % as compared to the 1-day compressive strength of a concrete prepared with comparative cementitious Mix 39. The 7-day compressive strength of a concrete prepared with inventive cementitious Mix 47 is increased by 38.7% as compared to the 7-day compressive strength of a concrete prepared with comparative cementitious Mix 39. The 28-day compressive strength of a concrete prepared with inventive cementitious Mix 47 is increased by 39% as compared to the 28-day compressive strength of a concrete prepared with comparative cementitious Mix 39. These results show that the use of the ASRI at a dosage of 4.5% Ca(NOs)2 by weight of cement increases both the early and late compressive strengths of concrete compositions.

[0112] The effect of the ASRI Admixture on Mortar Bar Expansion

[0113] Modified ASTM C 1567 Test Method

[0114] The ASTM C 1567 Standard Test Method is used for Determining the Potential Alkali-Silica Reactivity of Combinations of Cementitious Materials and Aggregate (Accelerated Mortar-Bar Method). According to ASTM C 1567, mortar bars are cast from cementitious compositions. The mortar bars are immersed in a IN NaOH solution at 80°C for 14 days. The change in the length of the mortar bars over the 14-day test period is measured. A mortar bar expansion of < 0.1% indicates inhibition of alkali-silica reaction. The present ASRI additive and admixture comprises a soluble alkaline earth metal ion, such as, for example, Ca2+cations from Ca(NOs)2. Because of the soluble nature of the Ca2+cations from Ca(NOs)2, the Ca2+cations leach into the mortar bar soak solution when tested in accordance with ASTM C1567.

[0115] The United States Army Corps of Engineers modified the ASTM C1567 Test Method to include an ingredient in the mortar bar soak solution to buffer the leaching of ions from the mortar bars. This test method permits detection within 30 days of the potential for deleterious alkali-silica reaction of combinations of cementitious materials, lithium nitrate admixture and aggregate in mortar bars. See CRD-C 662-10, Determining the Potential Alkali- Silica Reactivity of Combinations of Cementitious Materials, Lithium Nitrate Admixture, and Aggregate (Accelerated Mortar-Bar Method), first issued January, 2009; current revision, January 2010.

[0116] Applicant modified the ASTM C 1567 Test Method to include additional Ca2+ions in the mortar bar soak solution to buffer the leaching of soluble Ca2+ions from the mortar bars resulting from the use of the Ca(NC>3)2 alkali-silica reactivity inhibiting admixture in the cementitious composition from which the test mortar bar were prepared. The applicant- modified test method is referred to as ‘Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution. ” The concentration of the Ca2+ions added to mortar bar soak solution is 81% of that in mixing water of mortar, as shown in the table below. This ratio is the same ratio as that one used for the LiNO? admixture test according to Army Corps of Engineers CRD-C 662-10.

[0117] Mortar bars are prepared from cementitious compositions comprising hydraulic cement, mineral aggregate, the ASRI admixture containing Ca(NC>3)2 and water. Mortar bars having the dimensions of 1 inch x 1 inch x 10 inch (2.54 mm x 2.54 mm x 2.54 mm) are cast from the cementitious composition and moisture cured for 24 hours. Make an initial comparator reading. The mortar bar samples are immersed in water at 80°C for 24 hours. Take the zero reading. The mortar bar samples are then immersed in IN NaOH soak solution with additional Ca2+ions added to the soak solution at 80.0 ± 2.0°C. Make subsequent comparator readings of the mortar bar samples periodically for a 14-day period following the zero reading. Calculate the expansion of the mortar bar samples for the 14-day test period. If the 14-day expansion of the mortar bar sample is < 0.01%, then it can be concluded that the ASR expansion is mitigated by the inclusion of the ASRI admixture.

[0118] Pipe Test Method

[0119] Mortar bars are prepared from cementitious compositions comprising hydraulic cement, mineral aggregate, the ASRI admixture containing Ca(NO )2 and water. NaOH as Na2O is added to the mix water for preparing the cementitious compositions in order to accelerate the alkali-silica reaction, with 1.25% Na2O alkali level for cementitious compositions containing high reactive mineral aggregates and 2.5% Na2O alkali level for cementitious compositions having moderate and low reactive mineral aggregates. Mortar bars having the dimensions of 1 inch x 1 inch x 10 inch (2.54 mm x 2.54 mm x 2.54 mm) are cast from the cementitious composition and moisture cured for 24 hours. Make an initial comparator reading. The mortar bar samples are immersed in water at 80°C for 24 hours. A single mortar bar inserted into a pipe with 20 ml of water. The pipe is sealed and the mortar bar is stored in the sealed pipe at 80°C and 100% relative humidity for 24 hours. Take the zero reading. Make subsequent comparator readings of the mortar bar samples periodically for a 14-day period following the zero reading. Inject 20 ml of water into the pipe after each comparator reading. Calculate the expansion of the mortar bar samples for the 14-day test period. If the 14-day expansion of the mortar bar sample is < 0.01 %, then it can be concluded that the ASR expansion is mitigated by the inclusion of the ASRI admixture.

[0120] Table 7 below shows several cementitious compositions prepared with an illustrative embodiment of the ASRI admixture (Admixture 15), and using Hercules Type I / II cement and a crushed limestone aggregate obtained from Brooks (Kentucky, USA) with additional Ca2+ ions added to the mortar bar soak solution. ASR of the cementitious mixtures was analyzed by measuring the expansion of mortar bars cast with Comparative Mixes 48-50 and inventive Mixes 51-53 in accordance with the Modified ASTM C 1567 Test Method described herein. As shown in FIG. 4, Admixture 15 at a dosage amount of 4% by weight is effective at maintaining the expansion of mortar bars below 0.01% expansion. The results of FIG. 4 demonstrate Admixture 15 at a dosage amount of 4% by weight is effective mitigating alkali-silica reaction in cementitious mixtures prepared with Hercules Type I / II cement and a crushed limestone aggregate.Table 7

[0121] The grading of the mineral aggregate (Brooks, Kentucky, USA) used in the comparative and inventive cementitious mixes in Table 7 are set forth in Table 7A below:Table 7A

[0122] Table 8 below shows several cementitious compositions prepared with an illustrative embodiment of the ASRI admixture (Admixture 15), and using Hercules Type I / II cement and a crushed limestone aggregate obtained from Brooks (Kentucky, USA) and an initial 2.5% Na2O alkali level. ASR of the cementitious mixtures was analyzed by measuring the expansion of mortar bars cast with Comparative Mix 54 and inventive Mixes 55-58 in accordance with the Pipe Test Method described herein. As shown in FIG. 5, Admixture 15 ata dosage amount of 2% by weight is effective at maintaining the expansion of mortar bars below 0.01% expansion when tested by the Pipe Test Method. The results of FIG. 5 demonstrate Admixture 15 at a dosage amount of 2% by weight is effective mitigating alkalisilica reaction in cementitious mixtures prepared with Hercules Type I / II cement and a crushed limestone aggregate.Table 8

[0123] The grading of the mineral aggregate (Brooks, Kentucky, USA) used in the comparative and inventive cementitious mixes in Table 8 are set forth in Table 8A below:Table 8A

[0124] Mortar bars were prepared from the cementitious compositions shown in Table7 for testing in accordance with the Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution, except that borosilicate glass was used as the aggregate instead of the aggregate obtained from Brooks. Mortar bars were prepared from the cementitious compositions shown in Table 8 for testing in accordance with the Pipe Method, except that borosilicate glass was used as the aggregate instead of the aggregate obtained from Brooks and the Na2O alkali level was 1.25%. The results are shown in FIG. 6. The results indicate that a dosage of 5% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0125] Mortar bars were prepared from the cementitious compositions shown in Table8 for testing in accordance with the Pipe Method, except that crushed natural gravel from Delta (Colorado, USA) was used as the aggregate instead of the aggregate obtained from Brooks and the Na2O alkali level was 1.25%. Test mortar bars prepared with cementitious compositions containing 2%, 5% and 6% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NOs)2 addition. The results are shown in FIG. 8A. The results indicate that a dosage of 5% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0126] Mortar bars were prepared from the cementitious compositions shown in Table 7 for testing in accordance with the Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution, except that crushed natural gravel from Delta (Colorado, USA) was used as the aggregate instead of the aggregate obtained from Brooks. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4% and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NC>3)2 addition. The results are shown in FIG. 8B. The results indicate that a dosage of 5% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0127] Mortar bars were prepared from the cementitious compositions shown in Table8 for testing in accordance with the Pipe Method, except that natural sand from Knelsen (Alberta, Canada) was used as the aggregate instead of the aggregate obtained from Brooks and the Na2O alkali level was 2.5%. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4%, 5% and 6% Ca(NOs)2 were tested against a control mortar barprepared from a cementitious composition without the Ca(NOs)2 addition. The results are shown in FIG. 9A. The results indicate that a dosage of 3% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0128] Mortar bars were prepared from the cementitious compositions shown in Table7 for testing in accordance with the Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution, except that natural sand from Knelsen (Alberta, Canada) was used as the aggregate instead of the aggregate obtained from Brooks. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4% and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NC>3)2 addition. The results are shown in FIG. 9B. The results indicate that a dosage of 4% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0129] Mortar bars were prepared from the cementitious compositions shown in Table8 for testing in accordance with the Pipe Method, except that natural sand from Pearl River (Louisiana, USA) was used as the aggregate instead of the aggregate obtained from Brooks and the Na2O alkali level was 2.5%. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4%, and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NOs)2 addition. The results are shown in FIG. 10A. The results indicate that a dosage of 4% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0130] Mortar bars were prepared from the cementitious compositions shown in Table 7 for testing in accordance with the Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution, except that natural sand from Pearl River (Louisiana, USA) was used as the aggregate instead of the aggregate obtained from Brooks. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4% and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NC>3)2 addition. The results are shown in FIG. 10B. The results indicate that a dosage of 3% Ca(NC>3)2 is effective at inhibiting alkali-silica reaction.

[0131] Mortar bars were prepared from the cementitious compositions shown in Table 8 for testing in accordance with the Pipe Method, except that crushed limestone from Pearl River (Louisiana, USA) was used as the aggregate instead of the aggregate obtained from Brooks and the Na2O alkali level was 2.5%. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4%, and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NC>3)2 addition. The results are shown in FIG. 11A. The results indicate that a dosage of 2% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0132] Mortar bars were prepared from the cementitious compositions shown in Table 7 for testing in accordance with the Modified ASTM Cl 567 Test with Ca2+Buffering in Soak Solution, except that crushed limestone from Pearl River (Louisiana, USA) was used as the aggregate instead of the aggregate obtained from Brooks. Test mortar bars prepared with cementitious compositions containing 2%, 3%, 4% and 5% Ca(NOs)2 were tested against a control mortar bar prepared from a cementitious composition without the Ca(NOs)2 addition. The results are shown in FIG. 11B. The results indicate that a dosage of 3% Ca(NOs)2 is effective at inhibiting alkali-silica reaction.

[0133] While the admixture composition, cementitious composition including the admixture composition, and methods of making the admixture and cementitious compositions have been described in connection with various illustrative embodiments, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiments for performing the same function disclosed herein without deviating therefrom. The illustrative embodiments described above are not necessarily in the alternative, as various embodiments may be combined to provide the desired characteristics. Therefore, the disclosure should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims.

Claims

CLAIMS:

1. A method for inhibiting alkali-silica reaction in a cementitious composition comprising preparing a cementitious composition comprising (i) hydraulic cementitious binder, (ii) mineral aggregate, and (iii) an alkali-silica reaction inhibiting amount of an alkaline earth metal nitrate.

2. The method of claim 1, wherein the alkaline earth metal nitrate is added to the cementitious composition as an admixture comprising (iii)(a) an alkali-silica reaction inhibiting amount of said alkaline earth metal nitrate, (iii)(b) a cement hydration retarder, and (iii)(c) solvent.

3. The method of claim 1, wherein said alkaline earth metal nitrate is selected from calcium nitrate, magnesium nitrate, and combinations thereof.

4. The method of claim 3, wherein said alkaline earth metal nitrate is calcium nitrate.

5. The method of claim 4, wherein said cement hydration retarder is selected from the group consisting of lignosulfonates, hydroxylated carboxylic acids, lignin, borax, citric acid, gluconic acid, phosphonic acid, tartaric acid, and their corresponding salts, phosphonates, carbohydrates and mixtures.

6. The method of claim 1, wherein said solvent is water.

7. The method of claim 1, wherein the amount of said alkaline earth metal nitrate in said admixture is from about 40 to about 50 weight percent, the amount of said cement hydration retarder is 5 weight percent or less, and the amount of said solvent is 10 weight percent or less, based on the total weight of the admixture.

8. The method of claim 6. wherein the amount of said alkaline earth metal nitrate in said admixture is about 42 to about 50 weight percent, the amount of said cement hydration retarder is 5 weight percent or less, and the amount of said solvent is 10 weight percent or less, based on the total weight of the admixture.

9. The method of claim 7, wherein the amount of said alkaline earth metal nitrate in said admixture is about 44 to about 50 weight percent, the amount of said cement hydration retarder is 5 weight percent or less, and the amount of said solvent is 10 weight percent or less, based on the total weight of the admixture.

10. The method of claim 8, wherein the amount of said alkaline earth metal nitrate in said admixture is about 46 to about 50 weight percent, the amount of said cement hydration retarder is 5 weight percent or less, and the amount of said solvent is 10 weight percent or less, based on the total weight of the admixture.

11. The method of claim 9, wherein the amount of said alkaline earth metal nitrate in said admixture is about 48 to about 50 weight percent, the amount of said cement hydration retarder is 2 weight percent or less, and the amount of said solvent is 8 weight percent or less, based on the total weight of the admixture.

12. The method of claim 2, wherein the least one cement hydration retarder comprises a salt of gluconic acid and a phosphonic acid, optionally, wherein the amount of the salt of gluconic acid present in the admixture composition is equal to or greater than the amount of the phosphonic acid present in the admixture composition.

13. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises gluconic acid, a salt of gluconic acid, and a phosphonic acid, optionally, wherein the amount of the gluconic acid present in the admixture composition is equal to or greater than the amount of the salt of gluconic acid present in the admixture composition and equal to or greater than the amount of the phosphonic acid present in the admixture composition.

14. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises gluconic acid, a salt of gluconic acid, and a phosphonicacid, wherein the amount of the salt of gluconic acid present in the admixture composition is less than the amount of the gluconic acid present in the admixture composition and greater than the amount of the phosphonic acid present in the admixture composition.

15. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises gluconic acid and a phosphonic acid, optionally, wherein the amount of the gluconic acid present in the admixture composition is equal to or greater than the amount of the phosphonic acid present in the admixture composition.

16. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises an organic acid other than gluconic acid and a phosphonic acid, optionally, wherein the amount of the organic acid present in the admixture composition is equal to or greater than the amount of the phosphonic acid present in the admixture composition.

17. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises a salt of gluconic acid, an organic acid other than gluconic acid and a phosphonic acid, optionally, wherein the amount of the salt of gluconic acid present in the admixture composition is equal to or greater than the amount of the organic acid other than gluconic acid present in the admixture composition and equal to or greater than the amount of the phosphonic acid present in the admixture composition.

18. The method of claim 2, wherein the at least one cement hydration retarder included in the admixture composition comprises a salt of gluconic acid, an organic acid other than gluconic acid and a phosphonic acid, wherein the amount of the salt of gluconic acid present in the admixture composition is equal to or greater than the amount of the organic acid other than gluconic acid present in the admixture composition and equal to or greater than the amount of the phosphonic acid present in the admixture composition.

19. The method of claim 18, wherein the amount of the organic acid other than gluconic acid is greater than the amount of the phosphonic acid20. A cementitious composition comprising hydraulic cement binder, mineral aggregate, an alkali-silica reaction inhibiting amount of an alkaline earth metal nitrate, and water.

21. The cementitious composition of claim 20, wherein the hydraulic binder is selected from Portland cement, masonry cement, alumina cement, refractory cement, magnesia cements, calcium aluminate cement, calcium sulfoaluminate cement, calcium sulfate hemihydrate cement, oil well cement, ground granulated blast furnace slag, natural cement, hydraulic hydrated lime, and mixtures thereof.

22. The cementitious composition of claim 20 or 21, wherein said cementitious composition further comprises an air entraining agent, air detraining agent, corrosion inhibitor, dispersant, coloring agent, pigment, plasticizer, super plasticizer, wetting agent, water repellant, fiber, dampproofing agent, gas forming agent, permeability reducing agent, pumping aid, antimicrobial agent, fungicidal agent, insecticidal agent, bonding agent, strength enhancing agent, shrinkage reducing agent, and mixtures thereof.

23. The cementitious composition of any one of claims 20 to 22, wherein the alkaline earth metal nitrate is present in the cementitious composition in an amount of about 2 weight percent to about 10 weight percent by weight of cement (cwt).

24. The cementitious composition of any one of claims 20 to 23, wherein the alkaline earth metal nitrate is present in the cementitious composition in an amount of about 2 weight percent to about 8 weight percent by weight of cement (cwt).

25. The cementitious composition of any one of claims 20 to 24, wherein the alkaline earth metal nitrate is present in the cementitious composition in an amount of about 2 weight percent to about 6 weight percent by weight of cement (cwt).

26. The cementitious composition of any one of claims 20 to 25, wherein the alkaline earth metal nitrate is present in the cementitious composition in an amount of about 4 weight percent to about 6 weight percent by weight of cement (cwt).

27. The cementitious composition of any one of claims 20 to 26, wherein the alkaline earth metal nitrate is present in the cementitious composition in an amount of about 4 weight percent to about 5 weight percent by weight of cement (cwt).

28. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a slump of 14 cm or greater as measured by ASTM Cl 43.

29. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a slump of 15 cm or greater as measured by ASTM Cl 43.

30. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a slump of 20 cm or greater as measured by ASTM Cl 43.

31. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits an air content of 2 percent by volume or less as measured by ASTM C231.

32. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits an air content of 1.5 percent by volume or less as measured by ASTM C231.

33. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits an air content of 1.25 percent by volume or less as measured by ASTM C231.

34. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 1-Day compressive strength of 15 Mpa (2175 psi) or greater as measured by ASTM C39.

35. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 1-Day compressive strength of 20 Mpa (2900 psi) or greater as measured by ASTM C39.

36. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 7-Day compressive strength of 35 Mpa (5076 psi) or greater as measured by ASTM C39.

37. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 7-Day compressive strength of 43 Mpa (6237 psi) or greater as measured by ASTM C39.

38. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 28-Day compressive strength of 45 Mpa (6527 psi) or greater as measured by ASTM C39.

39. The cementitious composition of any one of claims 20 to 27, wherein the cementitious composition exhibits a 28-Day compressive strength of 50 Mpa (7252 psi) or greater as measured by ASTM C39.

40. A method of preparing a cementitious for or structure comprising: preparing a cementitious composition comprising hydraulic cementitious binder, one mineral aggregate, and an alkali-silica reaction inhibiting amount of an alkaline earth metal nitrate, optionally a cement hydration retarder, and water; placing the prepared cementitious composition at a desired location; and allowing the cementitious composition to harden.

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