Abstract: A liquid accelerator composition for sprayed concrete, comprising aluminium sulphate, amorphous aluminium hydroxide, alkanolamine and an organic dibasic acid anhydride. The compositions allow the attainment of high early compressive strength, and they can be tailored to give good performance with a wide variety of cement types.

Abstract: The present invention provides cement compositions that comprise water, high alumina cement, a soluble phosphate, and cement kiln dust. The cement compositions optionally may be foamed with a gas. Methods of cementing also are provided that comprise: providing the cement composition; introducing the cement composition into a location to be cemented; and allowing the cement composition to set therein. The location to be cemented may be above ground or in a subterranean formation.

Abstract: A method of manufacturing a cementitious composite includes: (1) forming mixing an extrudable cementitious composition by first forming a fibrous mixture comprising fibers, water and a rheology modifying agent and then adding hydraulic cement; (2) extruding the extrudable cementitious composition into a green extrudate, wherein the green extrudate is characterized by being form-stable and retaining substantially a predefined cross-sectional shape; (3) removing a portion of the water by evaporation to reduce density and increase porosity; and (4) causing or allowing the hydraulic cement to hydrate to form the cementitious composite. Such a process yields a cementitious composite that is suitable for use as a wood substitute. The wood-like building products can be sawed, nailed and screwed like ordinary wood.

Abstract: Cement compositions with improved mechanical properties and associated methods are provided, which are useful in conjunction with subterranean well operations. In certain embodiments, the cement compositions comprise carbon fibers, rubber particles, a hydraulic cement material, sufficient water to form a pumpable slurry, and optionally other ingredients including a dispersant, a weighting agent, a retarding or accelerating agent, or the like.

Abstract: Concrete products and mixes with reinforcing carbon graphite fibers, the carbon fibers being provided in the form of resin coated warped beam fabric, and a method for producing reinforced concrete products, where semi-cured carbon fibers are mixed with concrete and then cured through the hydration step to result in the formation of strengthened concrete products.

Abstract: Concrete and/or cement products and mixes with reinforcing carbon graphite fibers having a length of about 2½ inches to about 3½ inches, and/or nano and/or micron sized carbon fibers, and a method of reinforcing concrete.

Abstract: An alkali-free accelerator for use with spray-applied cementitious compositions such as concrete and mortar is the reaction product in aqueous medium of amorphous aluminium hydroxide, aluminium sulphate, formic acid and phosphoric acid. These accelerators perform as well as known alkali-free accelerators and are exceptionally stable, even in hot conditions.

Abstract: A binder for self-compacting concrete includes, in dry weight of the-binder, 70 to 90% of Portland cement, 4 to 16% of calcium aluminate, 4 to 14% of calcium sulphate, an accelerator and a retarder, 0 to 2% of Ca(OH)2 and at least an additive with a water reducer. The calcium sulphate is in the form of anhydrite and the water reducer has at least a superplasticizer consisting of a water soluble or water dispersible organic compound, having at least an amino-di(alkylene-phosphonic) group and at least a polyoxyalkylated chain or at least one of its salts.

Abstract: A method and cement composition is provided for sealing a subterranean zone penetrated by a well bore, wherein the cement composition comprises zeolite, cementitious material, and water sufficient to form a slurry.

Abstract: Carbon-containing fly ash has been treated with optimum amounts of ozone. There is homogenous treatment of the fly ash with ozone and over saturation with ozone is avoided. In a further embodiment of the invention carbon, from various sources is oxygenated to be incorporated into concrete. The preferred oxygenating agent is ozone.

Abstract: This invention relates to the use of a filler derived from cereal husk, more particularly rice husk, in composite materials to enhance the flame retardant, antistatic, accelerator, plasticiser and blowing characteristics in various composite materials.

Abstract: The present invention relates to an improved high-performance permeable concrete obtained by spreading and compacting a mixture which comprises 1,500-1,850 kg/m3 of aggregates; 320-400 kg/m3 of Portland cement; 28-35% of the cement (90-140 kg/m3) of water; 2-5% of the cement (6-20 kg/m3) of a pigment; and 3-10% of the cement (10-40 kg/m3) of charcoal dust, 7-15% of the cement (22-60 kg/m3) being substituted for particulates of blast furnace slag, and having the compressive strength of 120-300 kgf/cm2 and the permeability coefficient of 2×10?2 cm/sec or more. The permeable concrete according to the present invention is environmental friendly and has excellent strength and permeability.

Abstract: A method is disclosed for constructing, verifying, and maintaining underground vaults that isolate and contain radioactive burial sites. The method employs a buoyant lift technique to isolate a block of soil containing the contaminates from the surrounding soil. An impermeable synthetic liner is embedded in the vault to enhance the integrity of the system. The integrity of the vault is monitored by a system of sensors placed both inside and outside of the sealed vault. The method eliminates the need to excavate or drill in the contaminated areas.

Abstract: A cement repair composition is provided for repairing thin concrete. The composition comprises, in weight percentages: fine aggregates, 50-80%; Portland cement, 10-20%; reinforcing fibers such as polyethylene, steel and fiberglass fibers, 0-5%; and a plurality of further additives. The additives preferably include a lithium admixture, an air entraining admixture and a water reducing chemical additive, and a shrinkage compensating chemical additive, in a combined weight percentage of 0.01 to 5%.

Abstract: Compositions are provided for increasing the electrical conductivity of concrete or controlled low-strength materials (flowable fill). One composition sets to produce a concrete and includes from 1% to 30% by weight of portland cement; from 1% to 30% by weight of fly ash having a carbon content as measured by loss on ignition of greater than 12%; from 40% to 90% by weight of an aggregate; from 0.1% to 20% by weight of carbon fibers; and water in a sufficient amount such that the composition sets to a concrete. Another composition is a self-compacting, cementitious flowable fill composition that includes from 1% to 30% by weight of portland cement; from 5% to 85% by weight of fly ash; from 0.1% to 20% by weight of carbon fibers; and water in a sufficient amount such that the composition sets to a material having a compressive strength of 8.3 MPa or less.

Abstract: Use of activated carbon powder in a cement formulation having vinyl polymers that results in effectively eliminating the problem of moisture retention due to void formation during mixing and atmospheric moisture uptake. In the compositions and methods described it has been determined that an adduct formed from the interaction of the activated carbon and vinyl polymers fills voids typically present in finished concrete products. The adduct within the voids results in a hydrophobic cement composition.

Abstract: A method and cement composition is provided for sealing a subterranean zone penetrated by a well bore, wherein the cement composition comprises zeolite, cementitious material, and water sufficient to form a slurry.

Abstract: The present invention relates to an additive which is added in order to reinforce cement. The additive comprises chlorides of alkali metals, alkaline earth metals and/or transition metals and oxides selected from the group consisting of alkali metal and alkaline earth metal oxides, aluminum oxide, silica, apatite and/or zeolites and comprises, in particular, a combination of sodium chloride, ammonium chloride, aluminium chloride, potassium chloride, calcium chloride, magnesium chloride, magnesium oxide, magnesium sulphate, sodium carbonate, silica, apatite and/or zeolites. Additives of this type can be used, inter alia, to stabilize/modify cement; consolidate sand and/or soil, such as when building roads, dykes, tunnels, foundations and the like, immobilize pollutants, during the injection of cement compositions, such as grouting, and for the production of concrete.

Abstract: The invention concerns a self-levelling concrete and a method for making a structural part from said concrete. The concrete which comprises aggregate and solid particles with size grading not more than 12 mm, comprises a superplasticizer which is a compound containing a least an amino-(dialkylene phosphonic) group and at least a polyalkylated chain, or one of its salts. The method is implemented by advantageously pumping the concrete using one or several immersion tubes with their injecting end at a lower level than the framework.

Abstract: A synthetic aggregate having a multiplicity of uses such as for mixing with a cementing material to form concrete, mortar or plaster is disclosed. The aggregate includes crushed fragments of a size which are capable of passing through mesh screen having sieve openings ranging from between about 19 mm and 75 microns. The aggregate fragments are made by curing and then crushing a compressed product. The compressed product is made by compressing an aqueous cementitious mixture comprising cement and at least one member selected from the group consisting of bottom ash and non-cementitious fly ash. The compressed product is cured so that it has a compressive strength of at least 600 psi.

Abstract: Systems for retarding setting in an oilfield well cement slurry comprise a solution of a phosphonate selected from methylene phosphonic acid derivatives and a phosphate, in particular selected from the following salts or the corresponding acids: mono-phosphates (ortho-phosphates PO42; meta-phosphates PO3), acyclic poly-phosphates (pyrophosphates P2O74, tripolyphosphates P3O105) or cyclic poly-phosphates. The system preferably may also comprise a retarder booster and is more particularly applicable to cementing at low or medium temperatures.

Abstract: The invention provides conductive concrete suitable for commercial and large-scale production. The conductive concrete uses carbonaceous particles as conductive phase, to achieve concrete with resistivities as low as 2 &OHgr;cm and compressive strengths over 30 Mpa (both measured at 28 days).

Abstract: An additive consisting of (poly)ethyleneglycol monocycloalkylether of a specified kind, (poly)alkyleneglycol or (poly)alkyleneglycol monoalkylether of another specified kinds, an organic phosphoric acid ester of still another specified kind and an antifoaming agent in a specified ratio, when used at a specified ratio, can provide hydraulic cement compositions with reduced bleeding of water after the placing and reduced dry shrinkage of hardened objects.

Abstract: A chemical agent for improving the engineering properties of soil includes a mixture of cementitious pozzalans (5 to 60% by mass), calcium sulphate (20 to 80% by mass), an oxide of calcium (15 to 50% by mass) and silica oxide (1 to 30% by weight). Monofilament fibers can also be included in the mix.

Abstract: The invention provides conductive concrete suitable for commercial and large-scale production. The conductive concrete uses carbonaceous particles as conductive phase, to achieve concrete with resistivities as low as 2 &OHgr;cm and compressive strengths over 30 Mpa (both measured at 28 days).

Abstract: The present invention discloses methods for 1) preventing and/or mitigating microbiologically influenced corrosion (MIC) and 2) controlling and/or reducing the growth of at least one anaerobic, facultative anaerobic, or microaerophilic microorganism, which includes the step of adding or applying a composition containing a borate salt to an area susceptible to MIC and/or growth of anaerobic, facultative anaerobic, or microaerophilic microorganisms, in an effective amount to 1) control and/or reduce the growth or 2) to prevent and/or mitigate the corrosion. The present invention also discloses various means of using the compositions of the present invention which contain borate salts and further sets forth methods for preventing and/or mitigating staining caused, at least in part, by at least one anaerobic, facultative anaerobic, or microaerophilic microorganism.

Abstract: A groundbed electrode for the protection of an electrical/electronic equipment installation is comprised of a strip of a mixture of approximately equal parts, on a volumetric basis, of powdered crystalline carbon and Portland cement buried in earth, a copper electrical conductor wire embedded in the buried strip, and with the electrical conductor wire being connected to the electrical/electronic equipment in electrical current-conducting relation.

Abstract: Binder compositions are provided which include a mineral binder and a silicon-containing carbon black. The silicon-containing carbon black can have attached an ionic or ionizable organic group or can be oxidized. Silicon-containing carbon blacks may be prepared by a furnace method. The binder compositions of the present invention have improved coloring and weathering properties in comparison to binder compositions prepared with conventional carbon blacks. Furthermore, the binder compositions that incorporate silicon-containing carbon blacks having ionic or ionizable organic groups attached exhibit excellent dispersibility, even in pelletized form. Articles such as roofing tiles can be prepared from the binder compositions. Also contemplated is a method of improving the color stability of a mineral binder composition. Silicon-containing carbon blacks as described above are added to the mineral binder composition.

Abstract: There are here disclosed carbon fibers for reinforcement of cement which are obtained by applying, onto the surfaces of carbon fibers, esters of oleic acid and aliphatic monovalent alcohols, esters of oleyl alcohol and monovalent fatty acids, polyoxyalkylene bisphenol ethers or polyether esters as sizing agents, and a cement composite material having a bending strength of 300 kgf/cm.sup.2 or more which contains cut carbon fibers having a fiber length of 10 to 50 mm at a mixing volume ratio of the cut carbon fibers to the cement matrix in the range of 1 to 5%. According to the present invention, there are provided the carbon fibers for reinforcement of cement which have excellent adhesive properties to the cement, good process passage properties through a direct spray gun and good bundling properties and which are suitable for a direct spray method, and the cement composite material using the carbon fibers and having high bending strength.

Abstract: A method for coloring cementitious systems using compacted inorganic granules, wherein said compacted inorganic granules comprise an inorganic pigment and a dispersing agent. Particularly, a method for coloring cementitious systems using compacted inorganic granules; wherein said compacted inorganic granules are produced by a process consisting of: (a) mixing an inorganic pigment and a dispersing agent, (b) compacting the mixture, (c) milling the compacted mixture, and (d) classifying the compacted mixture into at least one oversize material stream, at least one undersize material stream and at least one product stream of compacted inorganic granules; and wherein the coloring effect of the compacted inorganic granules in the cementitious system equals or exceeds the powder standard.

Abstract: A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of an inorganic acid, and from about 0.1 to about 4% by weight of a tetrafluoroborate of ammonia, an alkali metal or an alkaline earth metal. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Abstract: A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of a hexafluorosilicate salt, and free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Abstract: A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of phosphoric acid, and from about 0.1 to about 4% by weight of a source of fluoride ions. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Abstract: A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Abstract: A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of an inorganic acid, and from about 0.1 to about 4% by weight of a hexafluorosilicate of ammonia, an alkali metal or an alkaline earth metal. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Abstract: An improved lightweight cementitious product made up of an aqueous cementious mixture using cement and expanded shale, clay and slate mix, that can incorporate fly ash, lime, and the weight saving component, which is micronized polystyrene particles having particle sizes in the range of 50 to 2000 microns, and characterized by having water contents in the range of from about 0.5% to 50% v/v. The ultra low water compositions can be extruded and can be molded under high pressure.

Abstract: A carbon fiber-reinforced concrete containing a cement, a coarse aggregate, a fine aggregate, a carbon fiber and water, the carbon fiber having an average length not less than the maximum size of the coarse aggregate and also a tensile strength of at least 300 kgf/mm.sup.2.

Abstract: The present invention provides a short carbon fiber reinforced hydraulic composite material making the best use of physical properties of short carbon fibers incorporated as reinforcing material. Microparticles are deposited on the short carbon fibers in an amount of 0.5 to 3 wt. %. These microparticles also have a particle diameter of 5 microns or less.

Abstract: An oil and gas well cementing composition and method are shown utilizing hydraulic cement, water a cement hydration retarder and an additive which is effective over a selected time period degrade the retarder. The additive is a controlled release oxidizer which releases nascent oxygen over time to gradually oxidize the cement hydration retarder, thereby providing a single cement slurry design for cementing pipes for oil and gas wells where wide temperature differentials exist between the two ends of the pipe.

Abstract: An admixture for cement comprises phosphorous acid and/or a salt thereof or a waste fluid originated from an electroless nickel-plating process which contains phosphorous acid and/or a salt thereof. The admixture is used as a setting accelerator, a rust proofing agent for reinforcing steel or a frost resistive agent for concrete and mortar as hydraulic cement blends. The admixture not only permits improvement of the resulting concrete in the setting-accelerating effect, but also can maintain the compressive strength at a high level while maintaining the bleeding rate at a low level.

Abstract: An improved lightweight cementitious product made up of an aqueous cementious mixture that can incorporate fly ash, portland cement, sand, lime, and the weight saving component, which is micronized polystyrene particles having particle sizes in the range of 50 to 2000 microns, and characterized by having very low water contents, in the range of from about 0.5% to 5% v/v. The ultra low water compositions can be extruded and can be molded under high pressure.

Abstract: Binder compositions are provided which include a mineral binder and a silicon-containing carbon black. The silicon-containing carbon black can have attached an ionic or ionizable organic group or can be oxidized. Silicon-containing carbon blacks may be prepared by a furnace method. The binder compositions of the present invention have improved coloring and weathering properties in comparison to binder compositions prepared with conventional carbon blacks. Furthermore, the binder compositions that incorporate silicon-containing carbon blacks having ionic or ionizable organic groups attached exhibit excellent dispersibility, even in pelletized form. Articles such as roofing tiles can be prepared from the binder compositions. Also contemplated is a method of improving the color stability of a mineral binder composition. Silicon-containing carbon blacks as described above are added to the mineral binder composition.

Abstract: An improved lightweight cementitious product made up of an aqueous cementitious mixture that can incorporate fly ash, portland cement, sand, lime, and the weight saving component, which is micronized polystyrene particles having particle sizes in the range of 50 to 2000 microns. The final mix can be poured into molded products such as foundation walls, roof tiles, bricks and the like. The product can also be used as a mason's mortar, a plaster, a stucco or a texture.

Abstract: A method of recovering steel plant waste revert materials including blast furnace flue dust and sludges involves mixing the revert materials with water to provide a total moisture content of about 14-20% by weight, then adding Portland cement as a sole binder, mixing, and, when the water content is limited to about 18 to 20%, casting the mixture onto the ground in the form of a slab or, when the water content is limited to about 14 to 16% and an accelerator for curing the cement is used, casting the mixture onto a conveyor in the form of preformed streams, curing the cast mixture and breaking it up to provide 1/2 inch to 5 inch agglomerate particles that can be recycled to the blast furnace.

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: The invention relates to the cementing of high temperature wells. The retarder consists of a methylene phosphonic acid derivative and of a boric acid or a borate at least as acid as borax in an aqueous solution, in particular, Na pentaborate, in a preferred ratio of 0.08 to 0.92 parts by weight. A long setting time and a very swift compressive strength development are obtained at the same time.

Abstract: The invention relates to the cementing of high temperature wells. A cement retarder comprises a phosphonic acid derivative combined with borax in a weight ratio of phosphonic acid derivative to borax of about 0.025 to about 0.2. A long pumping time is realized with rapid compressive strength development following placement.

Abstract: A blended hydraulic cement binder, is disclosed, consisting of water, fly ash, Type III portland cement, Type I portland cement, slag cement, ground silica, boric acid, borax, citric acid and an alkali metal activator. The cement binder and sequences for mixing the composition, is particularly useful because it provides: time to mix all components adequately, unrestricted transporting time that can be terminated, at will, followed by alterable placement and finishing times. The cement binder can be used as a neat cement or it can be extended with fillers, such as sand and gravel, to make mortar or concrete, that rapidly gains very high structural strengths.

Abstract: A process is disclosed for producing a hydraulic cement binder for both general and special applications, consisting of water, cementitious materials, boric acid, borax, citric acid, an alkali metal activator, and with or without ground silica. This cement making process with sequences for mixing the composition, is particularly useful because it provides: time to mix all components adequately, unrestricted transporting time that can be terminated, at will, followed by alterable placement and finishing times. The process provides the means for creating a hydraulic cement binder that can be used as a neat cement or it can be extended with fillers, such as sand and gravel, to make mortar or concrete, that rapidly gains very high structural strengths.