Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.

Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: A cement composition consists essentially of (a) from 50% to 97% by weight (calculated on the total composition) of a Portland cement clinker, the sulfur content of which is from 0.5% to 10% by weight expressed as SO.sub.3 and the fluorine content of which is from 0.13% to 1.00% by weight expressed as F, and (b) from 3% to 50% by weight (calculated on the total composition) of an extender containing a carbonate selected from calcium carbonate, magnesium carbonate, calcium magnesium carbonate and mixtures thereof as its main constituent and having a median particle size (d.sub.50) of below 14 .mu.m. Preferably, the total content of C.sub.3 S and C.sub.2 S in the Portland cement clinker is at least 65%. A preferred carbonate is electrostatic precipitator dust extracted from cement kiln exhaust gases. The cement composition may be mixed with further components such as other extenders, retarding agents and aggregate.

Abstract: Compositions for low heat cements developed especially for massive concrete works and which exhibit a compressive strength/heat of hydration ratio of at least 7.0 at the age of 13 weeks. One of two inventions provides a powder prepared by mixing CaO, SiO.sub.2, and Al.sub.2 O.sub.3 materials, melting the mixture, quenching the melt, and grinding the quenched matter, the powder being composed mainly of amorphous substances and chemically having a CaO/SiO.sub.2 (molar ratio) of 0.8-1.5 and an Al.sub.2 O.sub.3 content of no more than 10 wt. %. The other invention provides a mixed powder comprising no less than 70 wt. % of a powder and no more than 30 wt. % of an addition (portland cement or the like), the powder being the same as that of the first invention in both predominance of amorphous substances and CaO/SiO.sub.2 (molar ratio) excepting the Al.sub.2 O.sub.3 content which is less than 12 wt. % in the second invention.

Abstract: Cuttable concrete capable of being cut and sculpted with traditional tools and process for the manufacture and moulding thereof. The concrete consists of a mixture of a volume V of mineral material essentially in the form of crushed oolitic limestone, a volume V1, less than V, of a carbonated binder, preferably lime and/or cement based, and excess water. The cuttable concrete is useful in the building industry, interior decoration, urban fittings and the manufacture of casting moulds.

Abstract: A concrete composition including a naturally-occurring, mineralogic silica source material as part of the binder. The silica source material may be, for example, feldspars, naturally-occurring zeolites, diatomaceous earths, clinoptilites, mordenites, chabozites, opaline silicas, novaculites, vitreous volcanic rocks (rhyolites, dacites, latites, andesites and their tuffs, and basalts), and high silica rocks (such as quartzite sands, sandstones and many igneous and metamorphic rocks such as. granites and schists), among others, having at least 50% by weight silica. The cementitious binder of the concrete composition may have a silica content of about 20-40% by weight from the mineralogic material. The compositions exhibit improved strength and endurance, including greater density and smoothness which imparts significantly improved surface characteristics to the material.

Abstract: A method is provided for making a fiber-reinforced slag gypsum cement lightweight hardened product. The method consists essentially of mixing (1) from 5 to 140 parts by weight of aggregates having a maximum size of not larger than 2000 .mu.m to (2) 100 parts by weight of a mixture which comprises 100 parts by weight of Portland cement, (3) from 20 to 350 parts by weight of slag fine powder which has a fineness ranging from 6,000 to 12,000 cm.sup.2 /g as Blaine's specific surface area, (4) from 0 to 20 parts by weight of lime, (5) from 20 to 100 parts by weight of calcium aluminate and gypsum fine powder, (6) 0.01 to 1.5 parts of a setting retardant; mixing water, prefoamed foams and reinforcing fibers with the mixture to obtain a slurry; subjecting the slurry to molding to obtain a molded product; removing the molded product to obtain a hardened product; and curing the hardened product with steam.

Abstract: The present invention concerns a quick setting composition capable of obtaining satisfactory strength developability irrespective of the fluctuation of the ingredients in a metallurgical slag, excellent in the strength developability at cold temperature, easy for coagulation control and inexpensive as well, which contains a cement ingredient comprising portland cement and/or mixed cement, 2 to 50% by weight at the integral ratio of a quick setting agent prepared by adding 3 to 20% by weight of an alkali carbonate at an internal ratio to a mixture comprising 40 to 95% by weight of a finely powdery metallurgical slag and 5 to 60% by weight of II-type anhydrous gypsum, based on the cement ingredient, and 0.1 to 5% by weight of a coagulation controlling agent comprising an organic acid type coagulation retarder and an alkali sulfate and/or calcium salt based on the total weight of the cement ingredient and the quick setting ingredient.

Abstract: There is disclosed a softy mud solidifying agent which comprises cement, and at least two members selected from the group consisting of pozzolanic substances, inorganic compounds and organic compounds. The solidifying agent is capable of solidifying dredged earth, sand, softy mud, etc. in such a manner that their mixture can be re-cast into water to form submerged banks, artificial fish-gathering places, etc., without causing water pollution.

Abstract: A cementitious composition capable of forming an early high strength cement when admixed with a liquid comprising a cementitious material of a specific chemical composition, surface area, and particle size distribution, the method of making such cementitious composition, and cements comprising said composition.

Abstract: Durable molded construction parts are disclosed, which are prepared from hydration products of a settable construction material comprising a hydraulically hardening mixture and at least one reinforcing material subject to degradation under alkaline conditions. The construction material has an alkali buffer capacity which does not exceed 0.005 acid equivalents per 100 grams of construction material, as measured in an aqueous suspension of the construction material 24 hours after suspension formation.

Abstract: Composite materials based on cement or gypsum materials reinforced by mixing with cellulosic fibers grafted with silylating agents. Processes for preparing these reinforced composites are also disclosed.

Abstract: A heat-curing cement composition comprising 60 to 75% by weight of 3CaO.SiO.sub.2, in which the total content of 3CaO.Al.sub.2 O.sub.3 and 4CaO.Al.sub.2 O.sub.3.Fe.sub.2 O.sub.3 is lower than 10% by weight, the alkali content is lower than 0.2% by weight as the Na.sub.2 O equivalent, the balance is composed mainly of 2CaO.SiO.sub.2 and gypsum, and the Blain specific surface area is 3500 to 5500 cm.sup.2 /g. This cement composition provides a hardened body when heat-cured under a high temperature of 35.degree. to 85.degree. C.