Abstract: The present invention relates to subterranean well cementing operations, and more particularly, to cement compositions that include high aspect ratio materials, and methods for using such cement compositions in subterranean formations. An example of a method of the present invention is a method of cementing in a subterranean formation. An example of a composition of the present invention is a cement composition for use in a subterranean formation.

Abstract: A well cement composition for plugging a bore at the location for initiating sidetracking to bore a lateral well is formulated as a slurry of hydraulic cement that contains at least two, but preferably all three of the following additives: (1) a source of silicon dioxide, (2) fracturing proppants and (3) an expansion compound selected from the group consisting of 1%-5% crystalline silica and 60%-99% MgO or CaO, and their mixtures.

Abstract: A self-compacting concrete and mortar additive is prepared, comprising an aqueous suspension matured and stabilized for 1-7 days, preferably 1-2 days, and having a consistency adapted to the dosing equipment used for dosing the additive when mixing concrete or mortar, and having a pH of 6.5-8, preferably 7 and containing 5-30, preferably 8-20, preferably 10-12% by weight of dry solid of a type of clay, consisting of clay minerals selected from the smectite, vermiculite and/or chlorite group.

Abstract: Provided herein are compositions and methods including hydraulic cement, supplementary cementitious material, and/or self-cementing material. Methods for making the compositions and using the compositions are provided.

Abstract: A method of manufacturing a hydratable cementitious material, which includes: a) providing at least one waste material containing calcium, silica, magnesium, aluminium, and/or iron; b) thermally treating each waste material to a first temperature such that surface water vapour present is substantially removed; and c) blending the treated waste material such that the resultant blend has a reactive oxide chemical/physical composition in the following range, by weight of the blend: Calcium Oxide 7.0 to 76% Alumina 0.1 to 30% Iron Oxide 0.4 to 19% Silica Oxide 1 to 36% Magnesia 0.1 to 2%. The resultant blend from step c) may subsequently be mixed with Portland cement.

Abstract: The disclosure provides methods and systems for sequestering and/or reducing carbon dioxide present in an industrial effluent fluid stream containing carbon dioxide. A scrubbing material comprising a first component, a second component (distinct from the first component), and preferably water, is contacted with the effluent fluid stream. The first component comprises a source of calcium oxide and a source of alkali metal ions. The second component comprises a slag having one or more reactive silicate compounds. Methods of reducing carbon dioxide from exhaust generated by combustion sources, lime and/or cement kilns, iron and/or steel furnaces, and the like are provided. Carbon dioxide emission abatement systems are also disclosed. Methods of recycling industrial byproducts are further provided.

Abstract: Hydraulic cements, such as Portland cements and other cements that include substantial quantities of tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminate (C3A), and/or tetracalcalcium alumino-ferrite (C4AF), are particle size optimized to have increased reactivity compared to cements of similar chemistry and/or decreased water demand compared to cements of similar fineness. Increasing hydraulic cement reactivity increases early strength development and release of reactive calcium hydroxide, both of which enhance SCM replacement and 1-28 day strengths compared to blends of conventional Portland cement and one or more SCMs, such as coal ash, slag or natural pozzolan. Decreasing the water demand can improve strength by decreasing the water-to-cement ratio for a given workability. The narrow PSD cements are well suited for making blended cements, including binary, ternary and quaternary blends.

Abstract: The invention relates to a construction panel, in particular for use in dry construction.

Abstract: A cement mixture is disclosed that includes an aqueous mending agent that is disbursed within but isolated from the cement mixture, wherein the aqueous mending agent will form molecular bonds with hardened cement that is formed by the cement mixture when the mending agent is permitted to flow within the hardened cement.

Abstract: A concrete formulation, which undergoes controlled deterioration in water, that can be used for making anchors for releasably tethering submarine devices at the seabed. The anchor may have handles for a device release mechanism or a central hole for a central device release mechanism. The formulation includes additives, which cause the cement to transform into non-binding Thaumasite over a pre-set period of time, leaving only natural material on the seafloor.

Abstract: Cementitious compositions and methods for making same, in which the cementitious compositions include 35-60 wt. % cementitious reactive powder (also termed Portland cement-based binder), 2-10 wt. % expanded and chemically coated perlite filler, 20-40 wt. % water, entrained air, and optional additives such as water reducing agents, chemical set-accelerators, and chemical set-retarders. In addition, the lightweight cementitious compositions may contain 0-25 wt. % on a wet basis secondary fillers such as expanded clay, shale aggregate, and pumice.

Abstract: A process for manufacturing concrete bodies at elevated temperatures including the steps of providing pre-selected amounts of cement, aggregate and water where the temperature of at least the aggregate and more likely the cement and water are heated to a temperature between about 32° C. and 45° C. The heated amounts of cement, aggregate and water are mixed at an elevated temperature within the aforementioned range and a set retarding, water reducing admixture added. The mixing is continued and the hot mixture including the set retarding, water reducing admixture is cast at an elevated temperature within the same range to provide a concrete body form or structure with improved short and long-term compressive strengths.

Abstract: The construction material on a plant basis PB (preferably miscantus) contains a binder and a mineralizer composed of a defined mixture M2 of calcium carbonate CaCO3 and magnesium carbonate MgCO3 that is prepared in an application-oriented manner, thereby resulting in a substantial improvement of its chemical, physical, and mechanical properties. The weight proportions of the components constituting said mixture M2 are comprised between approx. 60% and approx. 95%, preferably between 2/3 and 9/10, for the CaCO3, and between approx. 5% and approx. 40%, preferably between 1/10 and 1/3, for the MgCO3. The method for producing said construction material is rationalized by previously admixing the mineralizer to the binder, preferably Portland cement of strength class 52.5, directly at the binder plant according to determined specifications to obtain a mixture M1. The weight proportions of the components constituting the mixture M1 are comprised between approx. 50% and approx.

Abstract: Disclosed are compositions and methods for providing fluid-loss control in subterranean wells. Well-completion fluids contain fine particulate additives whose glass-transition temperatures are below the anticipated bottomhole temperature. The particles soften upon injection into the well, whereupon they soften and become deformable. The particles then migrate to the borehole wall and form a seal that reduces further fluid flow from the borehole into the formation. The additive may be supplied as a powder or in the form of a liquid suspension.

Abstract: Provided herein are compositions and methods including hydraulic cement, supplementary cementitious material, and/or self-cementing material. Methods for making the compositions and using the compositions are provided.

Abstract: A method of placing a concrete compositions including a) combining 3-40 volume percent cement, 5-50 volume percent fine aggregate, 5-50 volume percent coarse aggregate, and 10-22 volume percent water; b) adding 1.5-40 volume percent of prepuff particles to form a concrete composition; and c) pumping the concrete composition to a point higher in elevation than the delivery point of the concrete to place the concrete. The concrete composition contains less than 30 volume percent of other light weighting aggregates and the prepuff particles have an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.02 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3. The slump value of the placed concrete measured according to ASTM C 143 is greater than 1 inch and the concrete has a density of from about 40 to about 135 lb./ft3.

Abstract: A subject of the invention is a mixture comprising in proportions by mass: from 0.4 to 4%, preferably from 0.8 to 1.7%, of materials in the ultrafine particle size range, constituted by particles with a D90 smaller than 1 ?m and/or with a specific BET surface area greater than 6 m2/g; from 1 to 6%, preferably from 2 to 5%, of Portland cement; from 8 to 25%, preferably from 12 to 21%, of materials in the fine particle size range, constituted by particles the D10 and the D90 of which are comprised between 1 ?m and 100 ?m and with a specific BET surface area of less than 5 m2/g, different from the cement; from 25 to 50%, preferably from 30 to 42%, of materials in the medium particle size range, constituted by particles the D10 and the D90 of which are comprised between 100 ?m and 5 mm; and from 25 to 55%, preferably from 35 to 47%, of materials in the larger particle size range, constituted by particles the D10 of which is greater than 5 mm.

Abstract: Synthetic fibers, such as polypropylene fibers, are mixed in a shrinkage compensating concrete to provide restraint in lieu of conventional steel reinforcement used in a shrinkage compensating concrete. While the synthetic fibers have a low elastic modulus and low strength, they act to restrain expansion of the concrete in the same way that conventional steel rebar does. In addition, only a small amount of the synthetic fibers are needed to restrain the expansion. As a result, shrinkage compensating concrete can be used in more varied applications, and can be provided more quickly, easily and inexpensively. Construction time requirements and expenses of concrete structures are correspondingly reduced.

Abstract: A process for making a pervious concrete comprising a geopolymerized pozzolanic ash. Generally, the process includes mixing a solid aggregate and a geopolymerized pozzolanic ash binder together to form a pervious concrete mixture. Some examples of suitable aggregates comprise recycled carpet, recycled cement, and aggregates of coal-combustion byproducts. The geopolymerized pozzolanic ash binder is made by combining a pozzolanic ash, such as fly ash, with a sufficient amount of an alkaline activator and water to initiate a geopolymerization reaction. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof. In some aspects, the final concrete forms a solid mass in the form of pavement or a pre-cast concrete shape. The solid mass of concrete may have a void content of between about 5% and about 35%.

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: 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 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: In order to also be able to economically use iron ore dust which is created by the extraction and preparation of iron ore and has not been usable until now, the invention proposes an agglomerated stone comprising (in wt. %) 6-15% of a cement binding agent, up to 20% of a carbon carrier, up to 20% of residual and recyclable substances, optionally up to 10% of a coagulation and solidification accelerator and the remainder consisting of iron ore in a stone format in the form of particles having a particle size of less than 3 mm as well as possessing after three days an initial strength of at least 5 N/mm2 and after 28 days a cold compression strength of at least 20 N/mm2. As a result of the particular hardness St and form stability thereof even at high temperatures T, agglomerated stones according to the invention are especially suitable for use in shaft, corex or blast furnaces. The invention also relates to a method for producing agglomerated stones according to the invention.

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: Cementitious compositions in which the cementitious properties of fly-ash are carefully controlled. The cementitious compositions may be substantially free harsh acids and bases such as citric acids (?pH 2.2) and alkali metal activators including alkali hydroxides (?pH 12-14) and metal carbonates (?pH 11.6). The use of these harsh chemicals creates acid base reactions during use of the products. Instead of these harsh chemicals, a citric salt, for example potassium citrate, may be used as a reaction accelerator. Boric compounds may be used as a retarder in the compositions.

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 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: Synthetic fibers, such as polypropylene fibers, are mixed in a shrinkage compensating concrete to provide restraint in lieu of conventional steel reinforcement used in a shrinkage compensating concrete. While the synthetic fibers have a low elastic modulus and low strength, they act to restrain expansion of the concrete in the same way that conventional steel rebar does. In addition, only a small amount of the synthetic fibers are needed to restrain the expansion. As a result, shrinkage compensating concrete can be used in more varied applications, and can be provided more quickly, easily and inexpensively. Construction time requirements and expenses of concrete structures are correspondingly reduced.

Abstract: Compositions useful as coatings, wherein the compositions comprise a coating material and a material selected from the group consisting of: mortars and grouts in admixture with the coating material. The coatings may be water-based or solvent-based, and may be epoxies, polyurethanes, polyaspartic ester polymers and polyureas in some embodiments. Compositions according to the disclosure exhibit enhanced physical properties compared with the same compositions made in the absence of a mortar or a grout as an ingredient. Compositions according to some embodiments have at least one of a mortar or grout, and optionally both, evenly dispersed within the bulk of a coating material prior to its application to a substrate sufficiently that the particles of the mortar or grout, or both when both are selected to be present, are substantially completely surrounded by a curable reactive mixture that cures to form a polymeric material useful as a coating.

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: A high early strength pozzolan cement includes larger sized pozzolan particles blended with smaller sized hydraulic cement particles containing tricalcium silicate and/or dicalcium silicate (e.g., Portland cement). Excess calcium release from the hydraulic cement when mixed with water forms calcium hydroxide available for reaction with the pozzolan. The fineness of the hydraulic cement particles is substantially greater than the fineness of the pozzolan particles (e.g., about 1.25 to about 50 times greater). Reducing or eliminating coarse hydraulic cement particles that cannot fully hydrate but include unreacted cores reduces or eliminates wasted cement normally found in concrete. Replacing some or all of the coarse cement particles with pozzolan particles provides a pozzolan cement composition having significantly lower water demand compared to the hydraulic cement by itself.

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: 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 excellent in bending strength, dimensional stability and installing property such as handling property, flexibility performance and nail performance, as well as a process for manufacturing the product. Namely, the fiber reinforced cement composition comprises the following raw materials: a hydraulic inorganic material, a siliceous material and a woody reinforcement, wherein the siliceous material is an inorganic hollow material and/or an inorganic spherical material and a finely dividing inorganic hollow material and/or a finely dividing inorganic spherical material. The effects of the present invention, it is possible to obtain a fiber reinforced cement product having good bending strength, dimensional stability and installing property such as handling property, flexibility performance and nail performance.

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 and a finely dividing fiber reinforced cement product which is produced by said raw materials and cured in an autoclave.

Abstract: Paving blocks for photocatalytic paving comprising at least a base layer in cementitious material and a surface layer based on a cementitious composition comprising: at least a hydraulic binder, a photocatalyst capable of oxidizing organic and inorganic polluting substances present in the environment in the presence of environmental light, air and humidity, at least an aggregate, water and, optionally, a water reducing additive.

Abstract: Sorbent components containing calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents are added to the coal ahead of combustion and/or are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

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: An additive for Portland-cement slurries comprises a liquid silicate absorbed into a solid porous medium. The additive is incorporated in slurries designed for well-cementing applications. The liquid silicate functions as a retarder aid and dispersant when added to slurries for use at temperatures above about 85° C. The resulting solid product allows use of the liquid silicate in well-cementing operations as if it were a dry additive.

Abstract: A cementitious Grout 111MG, with improved thermal and electrical conductivity over Grout 111, for use in at least one of geothermal heat pump systems and metal electrical grounding rod systems, with improved conductivity achieved by means of substituting metal grit for sand, a cementitious grout where both Grout 111MG and Grout 111 have mix water pH level limitations so as not to be corrosive to metals, a new use for Grout 111 as a fill material surrounding electrical grounding rods for enhanced electrical conductivity over traditional grouts, and a new use where both Grout 111MG and Grout 111 may be utilized to surround at least one of geothermal heat pump sub-surface heat transfer fluid conductive tubing/piping and electrical grounding rods installed within at least one of a well/borehole, a trench, and a pit.

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: A cementitious composition capable of forming high early strength cement when admixed with water may comprise, for each 100% by weight, no more than about 60% by weight C3S, at least about 4% by weight C2S, and between about 7% and about 11% by weight SO3, wherein the cementitious composition has a particle size distribution such that substantially all of its particles are of a size of about 10 microns or smaller. A cementitious composition may have a ratio of weight % SO3 to weight % Al2O3 of at least about 1.5 and a particle size distribution such that substantially all of its particles are of a size of about 10 microns or smaller. An apparatus and method for making such a cementitious composition are also described.

Abstract: Methods and compositions involving the use of nitrogen-containing coordinated metal compounds for stabilizing chromium VI reducing metal cations. Exemplary uses include processes for making cement, and exemplary compositions include cement additives, concrete admixtures, as well as hydratable cement and cementitous compositions.

Abstract: A method of controlling release of an admixture in a cement-based composition involves intercalating an admixture (e.g. an accelerator, a set retarder, a superplasticizer) for the cement-based composition into a layered double hydroxide or mixture thereof. A cement-based composition prepared in such a manner and containing a cement-based material (e.g. cement, mortar or concrete) has better workability, especially in respect of slump-loss characteristics.

Abstract: Provided herein are compositions and methods including hydraulic cement, supplementary cementitious material, and/or self-cementing material. Methods for making the compositions and using the compositions are provided.

Abstract: The invention herein provides for an improved dye material composed of a concentrated dye element for mixture with an aqueous element prior to application.

Abstract: An improved freeze-thaw durability dry cast cementitious composition is provided that uses very small (0.1 ?m to 100 ?m average diameter) polymeric microspheres that are blended directly into the mixture and optionally gas-generating additives. The polymeric microspheres provide void spaces in the material matrix that act to increase freeze-thaw durability of the material. In this dry cast cementitious composition, polymeric microspheres act as pre-formed voids.

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: Hydraulic cement compositions that include a carbonate compound composition, e.g., a salt-water derived carbonate compound composition containing crystalline and/or amorphous carbonate compounds, are provided. Also provided are methods of making and using the hydraulic cements, as well as settable compositions, such as concretes and mortars, prepared therefrom. The cements and compositions produced therefrom find use in a variety of applications, including use in a variety of building materials and building applications.

Abstract: The disclosure provides methods and systems for sequestering and/or reducing carbon dioxide present in an industrial effluent fluid stream containing carbon dioxide. A scrubbing material comprising a first component, a second component (distinct from the first component), and preferably water, is contacted with the effluent fluid stream. The first component comprises a source of calcium oxide and a source of alkali metal ions. The second component comprises a slag having one or more reactive silicate compounds. Methods of reducing carbon dioxide from exhaust generated by combustion sources, lime and/or cement kilns, iron and/or steel furnaces, and the like are provided. Carbon dioxide emission abatement systems are also disclosed. Methods of recycling industrial byproducts are further provided.

Abstract: A concrete which includes in parts by weight: 100 Portland cement; 50 to 200 of a sand having a single grading with a D10 to D90 between 0.063 and 5 mm, or a mixture of sands, the finest sand having a D10 to D90 between 0.063 and 1 mm and the coarsest sand having a D10 to D90 between 1 and 4 mm; 10 to 50 of a particulate, substantially non-pozzolanic material having a mean particle size less than 15 ?m; 0.1 to 10 of a water-reducing superplasticizer; and 10 to 30 of water; which concrete is substantially free of silica fume; the concrete having a compressive strength greater than 100 Mpa at 28 days.