Abstract: A lightweight concrete composition containing from 10 to 90 volume percent of a cement composition, from 10 to 90 volume percent of particles having an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.03 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3, and from 0 to 50 volume percent of aggregate; where the sum of components used does not exceed 100 volume percent, and where after the lightweight concrete composition is set it has a compressive strength of at least 1700 psi as tested according to ASTM C39 after seven days. The concrete composition can be used to make concrete masonry units, construction panels, road beds and other articles.

Abstract: Spent Claus catalyst having a high alumina content is used as an ingredient in the manufacture of Portland cements in place of all or a portion of a conventional source of alumina. The spent Claus catalyst is preferably of a small particle size and can be ground to the desired fineness before mixing with the other ingredients that are heated in a conventional kiln to produce the cement composition. Finely ground spent Claus catalyst can also be used as an additive at levels of 0.1% to 2% by weight to increase the thickening time of shallow casing cement slurries.

Abstract: A cover composition that can be applied to a bulk material pile, such as landfill refuse, to protect the pile from wind, precipitation, and access by animals and insects is provided. The cover composition is a mixture of a liquid, typically, water; bentonite clay; and synthetic fibers. The composition may be enhanced by the addition of one or more of the following additives: Portland cement, pregelatinized wheat starch, synthetic polymers, soda ash, and latex paint. Unlike prior art cover compositions, the disclosed composition adheres well to waste material, most notably plastics, whereby the composition is easy to apply and provides a substantially uniform, durable protective cover to landfill refuse piles and other bulk materials. Methods of applying the composition to bulk material piles are also disclosed.

Abstract: Methods of reducing hydroxyl ions in concrete pore solutions are provided. Such methods are useful in providing resistance to gels which form in concrete due to the alkali-silica (ASR) reaction. The methods comprise adding a salt or mixture thereof to the concrete, in aqueous or solid form, the salt or salt mixture having cations higher in valence than the anions. The methods also comprise adding an acidic phosphate or a silicon-containing alkoxide to the concrete. The methods further comprise resisting and/or inhibiting ASR in airfield runway concrete pore solutions by applying a soluble salt or a mixture of soluble salts in solution or a deicing salt mixture in situ to the runway concrete. All of the above methods are useful in reducing hydroxyl ions in concrete. Such methods can be used to resist ASR in fresh concrete, in concrete that is setting, or in hardened concrete.

Abstract: A self-curing concrete is provided to absorb water from atmosphere from air to achieve better hydration of cement in concrete. It solves the problem that the degree of cement hydration is lowered due to no curing or improper curing, and thus unsatisfactory properties of concrete. According to the invention, high-performance self-curing agent about 0.1˜5 wt % of cement weight of the concrete is added to concrete during mixing. The self-curing agent can absorb moisture from atmosphere and then release it to concrete. The self-curing concrete means that no curing is required for concrete, or even no any external supplied water is required after placing. The properties of this self-cured concrete of this invention are at least comparable to and even better than those of concrete with traditional curing.

Abstract: A composition for use in construction that is substantially free of volatile organic compounds (VOC) that when applied to a surface produces a smooth or textured, water-shedding (hydrophobic properties), aesthetically-pleasing, protective continuous coating. The coated surface as well as the method of preparing and applying the composition is also provided.

Abstract: The use of silicate as a retarder enhancer at appropriate levels to enhance the retarding effect of retarders at high temperatures encountered downhole while accelerating the set of cement at lower temperatures encountered near to the surface.

Abstract: A method of preparing a mortar composition, comprising mixing of mortar materials comprising at least 25 to 45 parts by weight of high-early-strength portland cement, 40 to 60 parts by weight of sand, 0.05 to 0.12 parts by weight of polycarboxylic acid-based powdered water reducing agent, and 10 to 25 parts by weight of water, and not comprising any organic adhesives. Mixing of the mortar materials is achieved by agitating the same in an agitator until agitating load rapidly decreases. The mortar composition prepared in accordance with this invention has excellent ability to infiltrate into the surface to be adhered, and high bonding strength after hardening.

Abstract: A method of making durable, non-vitrified masonry units comprising fly ash, the method comprising mixing fly ash comprising a minimum of 15% CaO by weight and no more than about 10% loss on ignition, water, and an air entrainment agent to form a fly ash mixture; compacting the fly ash mixture in a shaping device by applying pressure of at least 1000 psi to the fly ash mixture; and curing the compacted fly ash mixture to cause the mixture to harden and gain strength.

Abstract: A novel cement slurry composed of cement and water that can be used in cement stabilization applications. The cement slurry compound itself is chemically treated, by means of a cellulosic or other thixotropic thickening agent(s) to create a thixotropic system wherein the wetted cement remains in suspension and does not settle out prior to use even without further mixing. A chemical retarder/stabilizer is also used to prevent the slurry from prematurely setting during shipping. A novel apparatus and method for mixing the novel cement slurry is disclosed to insure the exact proportioning of all ingredients and the proper wetting of the cement.

Abstract: A cement-containing composition, and in particular to a sand free composition employing effective amounts of cement, a superplasticizer, a metakaolin clay, an acrylic based co-polymer, and water, and which is especially adapted for use in manufacturing poles.

Abstract: The invention relates to a process for dedusting a pulverulent building material composition, preferably a factory dry mortar and in particular tile adhesive, joint filler, filling compound, sealing slurry, repair mortar, levelling mortar, reinforcing adhesive, adhesive for composite thermal insulation systems (CTIS), mineral render, fine filler and screed systems, at least one dedusting agent which is liquid at 20° C. being brought into contact with the pulverulent building material composition at a temperature of >40° C. Preferably this occurs by spraying.

Abstract: A hydraulic composition is provided. This composition exhibits an improved workability in its coating with a trowel, and accordingly, an improved working efficiency with no adverse effects on its physical properties. The hydraulic composition comprises at least one surfactant selected from anionic surfactants having foaming ability (group A), at least one surfactant selected from surfactants which are nonionic antifoaming agents (group B), and a water-soluble cellulose ether. The surfactants of group A and group B are respectively added at 0.000005 to 0.004% by weight (solid content) in relation to the powder ingredients in the hydraulic composition, and the water-soluble cellulose ether is added at 0.02 to 1.2% by weight of the hydraulic composition.

Abstract: The problems to be solved by the invention are to provide a fiber reinforced cement composition for obtaining a fiber reinforced cement product which is inexpensive and economical, and to provide pushing forward disposal of defective products. Namely, the fiber reinforced cement composition comprises a hydraulic inorganic material, a siliceous material, a woody reinforcement, a finely dividing fiber reinforced cement product and/or a finely dividing intermediate of fiber reinforced cement product which is produced by said raw materials.

Abstract: Ceramic precursor compositions and chemically bonded ceramic (CBC) materials, especially Ca-based, and a composite biomaterial suitable for orthopaedic applications. The CBC-system includes a binding phase (chemical cement) and additional phases with specified chemistry imparting to the biomaterial the ability of initial strength followed by interaction with the body tissue including body liquid, to form a resorbable or partly resorbable biomaterial. The ceramic precursor composition includes at least one silicate with Ca as the main cation with a resorption rate less or equal to that of the bone in-growth rate. The silicate will form the binding phase of the cured material. Implants and surface coated devices are also disclosed. The cured material exhibits a compressive strength exceeding 100 MPa.

Abstract: A strength improvement admixture composition is provided that increases the compressive strength of cementitious compositions without negatively increasing the setting time. The admixture comprises the components of a polycarboxylate dispersant and strength improvement additive.

Abstract: Described herein is a composition including a substantially potash-free hydraulic cementitious material and at least one polyol compound having an acyclic polyhydroxy backbone chain comprising four or five adjacent carbon atoms, wherein a hydroxyl group is attached to each carbon of the backbone chain, and wherein the composition includes an effective amount of at least one calcium silicate or calcium aluminate material in a crystalline phase. Also described herein is a composition including a substantially calcium hydroxide-free hydraulic cementitious material and at least one polyol compound having an acyclic polyhydroxy backbone chain comprising four or five adjacent carbon atoms, wherein a hydroxyl group is attached to each carbon of the backbone chain, and wherein the composition includes at least one alkali-activated binder. Also described herein are methods and admixtures for increasing the strength of a hydraulic cementitious material.

Abstract: An alkali-free accelerator for sprayed cementitious composition, such as concrete, is prepared by dissolving aluminium sulphate in water and amorphous aluminium hydroxide in water optionally containing amine, and adding at least one stabiliser which is glycolic acid, and optionally at least one defoaming agent.

Abstract: A cement retarder system for use in underground wells included a borate compound, an organophosphonate salt, and a copolymer formed from AMPS and a monomer selected from the group consisting of acrylic acid, acrylamide and mixtures thereof.

Abstract: A fiber cement composite material that incorporates a blend of bleached and unbleached cellulose fibers as a partial or complete substitute for premium grade cellulose pulp is provided. Bleached standard grade cellulose fibers are used in conjunction with unbleached, standard grade cellulose fibers to provide a fiber cement composite product having substantially equal or even superior flexibility and strength as an equivalent fiber cement composite material reinforced by premium grade, unbleached cellulose fibers. A synergistic combination of bleached and unbleached standard grade cellulose fibers to produce a composite material with the desired properties previously achievable only through the use of premium grade cellulose pulp.

Abstract: A method for producing concrete parts and a structure includes (i) supplying a first concrete composition based on a quick binder containing Portland cement, curing accelerator system based on Al2O3, CaO lime and SO3 sulphates, a retardant system and a superplasticizer, (ii) adding a releaser system for forming a second concrete composition and pouring the second concrete composition into a concrete form. The use of a releaser system and the preparation of the first concrete composition are also disclosed.

Abstract: The present invention relates to cement-containing compositions which are characterized in that they have a proportion of organosilicon compounds of greater than 0.15% by weight, based on the proportion of cement, the organosilicon compounds being based on at least one organosilicon compound selected from the group consisting of the alkoxysilanes and at least one selected from the group consisting of the alkoxysiloxanes, to a process for the preparation thereof and to the use thereof.

Abstract: A variety of methods and compositions are disclosed herein, including, in one embodiment, a method comprising: introducing a settable composition into a subterranean formation, wherein the settable composition comprises: a cementitious component comprising a hydraulic cement and cement kiln dust; a swellable particle; and water; and allowing the settable composition to set in the subterranean formation. Another embodiment comprises a settable composition comprising: a cementitious component comprising a hydraulic cement and cement kiln dust, a swellable particle, and water.

Abstract: The invention relates generally to a cement or gypsum composition having improved properties, which is prepared by incorporating an enzyme into a cement material such as a cement, mortar, or concrete, or into a gypsum product. The invention also relates to methods of manufacturing improved cement compositions and gypsum products, methods of improving the compressive strength of cement compositions and gypsum products, and methods of reducing the cost of such compositions by enabling the use of less expensive aggregates in the manufacturing process. More specifically, the invention relates to a cement composition or a gypsum composition, optionally including at least one aggregate and optionally including at least one pozzolan, comprising a cement material or gypsum optionally including aggregate(s) and pozzolan(s) having blended therein an enzyme.

Abstract: A fiber reinforced cement composition having the following raw material composition is provided to manufacture a fiber reinforced cement product which is excellent in bending strength, dimension stability, handling property, flexibility performance, and processability such as nail performance, as well as to provide a process for manufacturing the product. Namely, the fiber reinforced cement composition comprises a hydraulic inorganic material, a siliceous material and a woody reinforcement in a mass ratio of CaO to SiO2 contained in the hydraulic inorganic material and the siliceous material in the raw materials in a range of from 23:77 to 60:40.

Abstract: Low-density cement slurries for cementing subterranean wells are described that comprise alkali swellable polymers as thickening agents that provide slurry stability. The polymers are preferably added as liquid latex dispersions, and may also comprise a surfactant that is present at a concentration below its critical micelle concentration. Particular utility is observed when the solid-volume fraction (SVF) of the slurry is less than about 40 percent. Also described are a method for increasing the viscosity of a cement slurry and methods for cementing a subterranean well.

Abstract: Disclosed embodiments relate to well treatment fluids and methods that utilize nano-particles. Exemplary nano-particles are selected from the group consisting of particulate nano-silica, nano-alumina, nano-zinc oxide, nano-boron, nano-iron oxide, and combinations thereof. Embodiments also relate to methods of cementing that include the use of nano-particles. An exemplary method of cementing comprises introducing a cement composition into a subterranean formation, wherein the cement composition comprises cement, water and a particulate nano-silica. Embodiments also relate to use of nano-particles in drilling fluids, completion fluids, simulation fluids, and well clean-up fluids.

Abstract: The present invention relates to a formulation of a high-performance foamed cement material, comprising: at least one hydraulic binder, microparticles whose grain size ranges between 0.1 and 30 ?m, whose proportion ranges between 15% and 50% by mass in relation to the mass of hydraulic binder, mineral particles whose grain size ranges between 1 and 500 ?m, whose proportion ranges between 10% and 35% by mass in relation to the mass of hydraulic binder, the proportion of particles being lower than the proportion of microparticles, a hydrosoluble polymer thinning agent whose proportion ranges between 0.1% and 8% by mass in relation to the mass of hydraulic binder, water whose proportion is at most 40% by mass in relation to the mass of hydraulic binder, a foaming agent whose proportion ranges between 0.1% and 10% by mass in relation to the mass of hydraulic binder.

Abstract: An admixture formulation of at least one polycarboxylate dispersant and at least one naphthalene dispersant is provided. When the polycarboxylate dispersant and the naphthalene dispersant of the admixture formulation are combined at various ratios the admixture formulation reduces the tendency for bleed and segregation in cementitious mixtures without increasing water demand, retarding setting, increasing water sensitivity, promoting high viscosity, or reducing flow retention.

Abstract: The problems to be solved by the invention are to provide an inorganic composition for obtaining an inorganic product which is excellent in physical property such as installing property, and which is economical price, as well as a process for manufacturing the product. Namely, the present invention provides, as a means to solve the conventional problems, an inorganic composition comprising the following raw materials: a hydraulic inorganic material, a siliceous material and a woody reinforcement, wherein the hydraulic inorganic material is a cementitious material, the siliceous material is a mixture of a rough particle size of siliceous material and a finely particle size of siliceous material, and the woody reinforcement is a wood powder and a pulp. The effects of the present invention, it is possible to obtain an inorganic product which is excellent in physical property such as installing property, and which is economical price.

Abstract: A concrete obtained through mixing a composition comprising the following constituents: a) 21 to 27% of a hydraulic binder, b) 52 to 68% of aggregate particles having a size of between 0.02 mm and 5 mm, c) 2 to 6% of pozzolanic reaction particles having a particle size of between 0.1 and 1 micron, d) up to 10% of filler having a particle size between 10 and 200 microns, e) 0.32 to 1.6% of a dispersant, f) 0.1 to 1.2% of fibres, g) 0.02 to 0.1% of a defoamer agent, and h) 7 to 10% of water, each percentage being the percentage by weight of the respective constituent relative to the sum of the weights of constituents a) to h). The concrete obtained is particularly suitable for polished flooring overlay.

Abstract: The invention describes improved mortar compositions that can reach compressive strength values up to six times more than the obtained ones by conventional mortars at the first hours of setting, as well as up to three times more at 28 days of setting. Cementitious materials, such as Portland cement and clinker of Portland cement were refined in a high energy mill until reaching the greater fineness possible (100%<10, um) to obtain a material with greater mechanical resistance by compression that those that are reached with normal cement. The compositions of the invention containing the refined cementitious material as well as refined and suitably distributed sand, develop compressive strengths substantially higher (greater to 100 MPa).

Abstract: Of the many methods and compositions provided herein, one method comprises providing a cement composition, wherein the cement composition comprises a cementitious component and an additive comprising a polymer, a phosphorus component, a polyvalent metal ion, an oil-based liquid, and a surfactant; introducing the cement composition into at least a portion of the subterranean formation; and allowing the cement composition to at least partially set therein. Another method provided herein comprises providing a cement composition that comprises a cementitious component and an additive comprising a polymer, a phosphorus component, a polyvalent metal ion, an oil-based liquid, and a surfactant; introducing the cement composition into a void located in a pipe string; and allowing the cement composition to at least partially set therein.

Abstract: Disclosed herein are defoamers comprising ethylene glycol, a defoaming hydrocarbon base fluid, and a non-ionic surfactant wherein the hydrocarbon base fluid comprises an internal olefin or a straight-chain n-alcohol, and wherein the non-ionic surfactant is present in the defoamer in an amount in the range of from about 1% to about 10% by weight of the defoamer. Also disclosed herein are cement compositions comprising water, hydraulic cement, and a defoamer, wherein the defoamer comprises ethylene glycol, a non-ionic surfactant, and a defoaming hydrocarbon base fluid wherein the hydrocarbon base fluid comprises an internal olefin or a straight-chain n-alcohol, and wherein the non-ionic surfactant is present in the defoamer in an amount in the range of from about 1% to about 10% by weight of the defoamer.

Abstract: An exemplary composition for enhancing water repellency in cementitious material comprises a hydrophobic material solute that is dissolved in a glycol ether solvent. Thus, the composition is provided in the form of a non-aqueous solution or emulsion wherein water is in a noncontinuous phase. The use of such compositions to modify cementitious compositions and the cementitious materials obtained thereby are also described.

Abstract: This invention is a fiber reinforced cement composition comprising the following raw materials: a hydraulic inorganic material, a siliceous material, and a woody reinforcement wherein the siliceous material is a mixture of an average particle size of not less than 15 um and not more than 50 um which is burned ash of coal and/or rhyolite and an average particle size of not less than 1 um and not more than 15 um which is burned ash of coal and/or rhyolite.

Abstract: A fluid loss additive for hydraulic cement, comprising a polyvinyl alcohol resin and a fluid loss ameliorating sulfonic acid-functionalized co-resin, where the polyvinyl alcohol has a characteristic viscosity in the range of about 1 to about 25 cps. The invention includes, in some embodiments, an aqueous concentrate of the PVOH resin and the sulfonic acid-functionalized co-resin, where the total resin content is in the range of about 10% to about 40% and the viscosity is less than 15,000 cps. By way of the invention it is possible to adjust hydraulic cement slurry characteristics in real time upon demand and reduce inventory by providing a concentrated aqueous fluid loss additive.

Abstract: The object of the present invention is to provide an inorganic board whose dimensional stability, anti-freezing and fusing properties, and the like are much improved. To attain this object, an inorganic board is manufactured using a method comprising: preparing a raw material slurry by the dispersing of a cementitious material, silica-containing material, woody reinforcement, and mica in water, forming a papered mat by sheet forming the raw material slurry, pressing the papered mat, and curing the pressed papered mat in an autoclave at a temperature higher than 150° C., wherein the mass ratio of the cementitious inorganic material and silica-containing material is set to be in the range of between 35:65 and 45:55, to promote the curing reaction of the inorganic board and improve its dimensional stability and anti-freezing and fusing properties.

Abstract: Cement compositions including environmentally compatible defoamers and methods of using such cement compositions are provided herein. An example of a method is a method of reducing foam generation in a cement composition. An example of a composition is a is a cement composition comprising water, hydraulic cement, and a defoamer.

Abstract: The invention relates to a method for the accelerated dehydration of sludges in sludge disposal areas, especially of sludges from rivers and harbors, by the exclusive use of anionic polymer flocculants and the use of materials obtained according to the inventive method.

Abstract: Rapid repair and retrofit of existing infrastructures demand durable high early strength materials that not only deliver sufficient strength within a few hours of placement but also significantly prolong the maintenance interval. The invention comprises a class of newly developed polyvinyl alcohol (PVA) fiber-reinforced high early strength engineered cementitious composites (ECC) materials featuring extraordinary ductility. The tailoring of preexisting flaw size distribution through non-matrix interactive crack initiators in the composite matrix results in high tensile ductility. The resulting high early strength ECC materials are capable of delivering a compressive strength of 21 MPa (3.0 ksi) within 4 hours after placement and retaining long-term tensile strain capacity above 2%.

Abstract: A lightweight structural concrete with screw-ability and nail-ability similar to wood is composed of a non-structural and ultra lightweight aggregate such as expanded perlite or a combination of expanded perlite and polystyrene beads of a particular size distribution and volume amount, entrained air cells of another specific size distribution and volume amount, and dense cementitious composition of a cement binder, a fine grade structural filler no larger than concrete sand grade, a pozzolan, and optional micro-fibers for reinforcement. This structural concrete matrix is optimized to hold 13 gauge T-nails and bugle head wood screws with thread ranging from 8 to 11 threads per inch and diameter of 0.10? to 0.137?. The resulting concrete will have consistent screw-ability and nail-ability similar to that of wood.

Abstract: Concrete structures and components with improved strength and toughness. A uniform mix of first constituents comprises: cement of Blaine fineness of 280-360 m2/kg; sand at a mass ratio of 0.75-1.25 of the cement; silica fume at a mass ratio of 0.15-0.4 of the cement; silica flour at a mass ratio of 0.15-0.3 of the cement; and microinclusions at a mass ratio up to 0.35 of the cement. This is then mixed with a blend of second constituents comprising a specified amount of an HRWRA and an amount of water at a mass ratio of 0.2-0.35 of the cement. This is mixed sufficiently to form a uniform cement-based paste to which an amount of macrofibers at a mass ratio of up to 0.35 of the cement is added to yield a uniform product. Nanoinclusions may be added to improve crack resistance and increase density.

Abstract: A fiber reinforced cement composition comprising the following raw materials: not less than 25% by mass and not more than 45% by mass of a hydraulic inorganic material; not less than 50% by mass and not more than 65% by mass of a siliceous material; not less than 5% by mass and not more than 12% by mass of woody reinforcement; not less than 0.25% by mass and not more than 1.5% by mass of a water soluble resin, wherein the hydraulic inorganic material is a Portland cement, the siliceous material is an amorphous material selected from the group consisting of fly ash, silica fume, blast furnace slag, perlite powder, glass powder, and mixtures thereof; the woody reinforcement is needle-leaves-tree unbleached kraft pulp and/or needle-leaves-tree bleached kraft pulp and used newspaper, and the water soluble resin is a polyvinyl alcohol resin.

Abstract: A lightweight cementitious composition containing from 10 to 90 volume percent of a cement composition, from 10 to 90 volume percent of particles having an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.03 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3, and from 10 to 50 volume percent of sand and/or other fine aggregate, where at least a portion of the sand and/or fine aggregate has a fineness modulus of less than 2; where the sum of components used does not exceed 100 volume percent, and where after the lightweight cementitious composition is set it has a compressive strength of at least 1700 psi as tested according to ASTM C39 after seven days. The cementitious composition can be used to make concrete masonry units, construction panels, road beds and other articles.

Abstract: Concrete with improved strength and toughness. A uniform mix of first constituents comprises: cement of Blaine fineness of 280-360 m2/kg; sand at a mass ratio of 0.75-1.25 of the cement; silica fume at a mass ratio of 0.15-0.4 of the cement; silica flour at a mass ratio of 0.15-0.3 of the cement; and microinclusions at a mass ratio up to 0.35 of the cement. This is then mixed with a blend of second constituents comprising a specified amount of an HRWRA and an amount of water at a mass ratio of 0.2-0.35 of the cement. This is mixed sufficiently to form a uniform cement-based paste to which an amount of macrofibers at a mass ratio of up to 0.35 of the cement is added to yield a uniform product. Nanoinclusions may be added to improve crack resistance and increase density.

Abstract: A polymeric fluid loss additive for hydraulic cement which includes a polymer component which exhibits delayed hydration. The fluid loss additive is suitable for use in cement slurries which may be subjected to elevated temperatures, as is common in oil and gas drilling operations. By way of the invention, cement slurries are provided which have improved fluid loss properties at high temperatures, while maintaining manageable rheologies that are conducive to mixing, pumping, and the like across a broad range of temperatures.

Abstract: Concrete and mortar composites can be made with two or more sizes of fibers therein. The different sized fibers can be used to adjust the toughness and reliability of the composite material. The different sized fibers can also be used to increase the deflection of concrete or mortar compositions. The variable length of fibers provide for smaller fibers to exist in corners for more strength in smaller spaces. Different mixes of sizes of fibers can also adjust the stiffness of a concrete or mortar composite material. The fibers can be made from a variety of materials, lengths, shapes, aspect ratios or diameters. The fibers can make up variable portions of the composition. Mixing different aspect ratios of fibers together can be used to prevent clumping or balling of the fibers. Mixing of different modulus of elasticity fibers in different ratios can add to the toughness and strength of the composite.

Abstract: Provided is a fiber reinforced cement board having good installation properties such as nail performance, flexibility performance and handling performance, as well as other favorable physical properties. The board has an absolute dry specific gravity of not less than 1.20 and not more than 1.30 and comprises as raw materials not less than 28% by mass and not more than 32% by mass of a hydraulic inorganic material, not less than 54% by mass and not more than 58% by mass of a siliceous material, not less than 8% by mass and not more than 12% by mass of a woody reinforcement, not less than 2% by mass and not more than 5% by mass of mica, and not less than 0.5% by mass and not more than 1.25% by mass of a water-soluble resin.

Abstract: According to various embodiments, gas-generating additives for use in a cement composition comprise: a gas-generating material at least partially coated with a mixture comprising a fatty acid ester of sorbitan, glycerol, or pentaerythritol and having a shelf life of about 12 months or greater. The gas-generating additives may also include a C8-C18 hydrocarbon. In more embodiments, cement compositions comprise: a gas-generating material at least partially coated with a mixture comprising a fatty acid ester of sorbitan, glycerol, or pentaerythritol and a C8-C18 hydrocarbon for increasing a shelf life of the gas-generating material. In yet more embodiments, cement compositions comprise: a cement; a fluid for making the cement composition pumpable; a hydrogen-generating material at least partially coated with a mixture for delaying a hydrogen-generating reaction, the mixture comprising sorbitan monooleate and an isoparaffin.