The invention provides cement additives comprising calcium sulfate and silica which are derived from a material comprising perovskite and silica, along with cements and cementitious products comprising the cement additives. The invention also provides methods for the making the cement additive and cements and cementitious products comprising the cement additives.

Foundry casting elements and methods of forming the same, the methods including: forming an aqueous slurry including an inorganic binder precursor, shaping the slurry using a pattern, curing the shaped slurry using a low temperature solidification process to form a casting element, and removing the pattern from the casting element.

Foundry casting elements and methods of forming the same, the methods including: forming an aqueous slurry including an inorganic binder precursor, shaping the slurry using a pattern, curing the shaped slurry using a low temperature solidification process to form a casting element, and removing the pattern from the casting element.

A method of producing a cement composition with reduced carbon emissions may include: defining cement constraints comprising at least one cement property; calculating a set of cement compositions which satisfy the cement constraints, using cement property models corresponding to the cement constraints; calculating a carbon emission associated with each of the cement compositions in the set of cement compositions using a carbon footprint model; selecting a cement composition from the set of cement compositions; and preparing the cement composition.

A method of producing a cement composition with reduced carbon emissions may include: defining cement constraints comprising at least one cement property; calculating a set of cement compositions which satisfy the cement constraints, using cement property models corresponding to the cement constraints; calculating a carbon emission associated with each of the cement compositions in the set of cement compositions using a carbon footprint model; selecting a cement composition from the set of cement compositions; and preparing the cement composition.

Provided is a method for producing a silica aerogel blanket having high thermal insulation and high strength, wherein an acicular metal-silica composite is added to a step of preparing a silica precursor solution during the production of the silica aerogel blanket to produce a silica aerogel blanket having characteristics of high thermal insulation, high strength, high thermal resistance and low dust.

A light weight geopolymer concrete, having a specific gravity less than 2.0, more typically between 1 and 1.3, is provided that has compressive strength comparable to or greater than ordinary Portland concrete. The light weight geopolymer concrete has low shrinkage, expansion, and cracking, and substantially no loss of compressive strength when exposed to high temperatures of 800° C. or greater, as would occur in a fire. To be useful as a load bearing member for general applications, such as residential housing, the compressive strength of the light-weight geopolymer concrete should be at least 10 MPa, preferably greater than 12 MPa, for example greater than 15 MPa. For more demanding uses, the compressive strength should be near or at the compressive strength of concrete, that is, greater than 20 MPa, preferably greater than 30 MPa, and optimally greater than 35 MPa. To be useful during and after a fire, the strength must not be reduced by more than 20%, preferably not less than 10%, optimally not reduced at all when exposed to heat up to 800° C. Embodiments of the invention include low-density high-temperature-resistant geopolymer concrete which increases load bearing strength when exposed to temperatures above 400° C., preferably at 800° C. Key constituents for forming most embodiments include a geopolymer source such as fly ash, a cement-coated expanded vermiculite, a fiber such as wollastonite, and soluble silicates such as alkali silicates.

A sound insulating material, a sound insulating plate, and a partition structure of a train carriage are provided. The sound insulating material comprises the following components in weight ratio: 2-8 parts of tricalcium silicate; 4-10 parts of calcium hydroxide; 10-30 parts of aluminosilicate; 4-10 parts of alumina; 5-15 parts of iron oxide; 10-30 parts of a binder; and 5-10 parts of a curing agent, wherein the binder is at least two of lithium silicate, sodium silicate and calcium silicate; the curing agent is at least one of lithium oxide, magnesium oxide and silica; and the mixture of the aluminosilicate, alumina and iron oxide expands at 1000° C.-1350 ° C. to form particles. The sound insulating plate made of this material is lightweight and has a sound insulation capacity of 35-42 dB.

The invention relates synthetic silicate granules comprising a mixture of SiO.sub.2, Al.sub.2O.sub.3 and Na.sub.2O, which can be obtained by sintering; to their use in manufacturing an agglomerate stone material and to the agglomerate stone material resulting thereof.

The invention relates to a process for producing a composite comprising: a. providing a particulate material, wherein the particulate material comprises minerals having a content of at least 30% m/m of calcium, magnesium, aluminium, silicon, potassium or iron, or a combination of two or more thereof. b. providing an aggregate, c. providing a primary additive, wherein the primary additive comprises a sugar or derivative thereof, a polyol or derivative thereof, an organic acid, an organic acid salt or an inorganic acid, or any combination of two or more thereof, d. mixing the particulate material, the aggregate and the primary additive with water to form a mixture, and e. carbonating the mixture in the presence of carbon dioxide, wherein the concentration of carbon dioxide is greater than about 2 vol %.