An inorganic mortar system for chemical fastening of an anchor in mineral substrates can contain at least one hard aggregate having a Mohs-hardness of greater than or equal to 8. The inorganic mortar system contains a curable aluminous cement component A and an initiator component B for initiating the curing process. Component A contains at least one blocking agent selected from boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, phosphoric acid, and salts and mixtures thereof. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. The use of at least one hard aggregate having a Mohs-hardness of greater than or equal to 8 in an inorganic mortar increases load values and reduces shrinkage. A method can be used for chemical fastening of an anchor, preferably of metal elements, in mineral substrates, such as structures made of brickwork, concrete, pervious concrete, or natural stone.

An inorganic mortar system for chemical fastening of an anchor in mineral substrates can contain at least one hard aggregate having a Mohs-hardness of greater than or equal to 8. The inorganic mortar system contains a curable aluminous cement component A and an initiator component B for initiating the curing process. Component A contains at least one blocking agent selected from boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, phosphoric acid, and salts and mixtures thereof. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. The use of at least one hard aggregate having a Mohs-hardness of greater than or equal to 8 in an inorganic mortar increases load values and reduces shrinkage. A method can be used for chemical fastening of an anchor, preferably of metal elements, in mineral substrates, such as structures made of brickwork, concrete, pervious concrete, or natural stone.

A process for the production of a mineral foam includes separately preparing a slurry of cement and an aqueous foam, wherein the cement slurry includes water and Portland cement as well as calcium silicate hydrate crystallization seeds; contacting the slurry of cement with the aqueous foam to obtain a slurry of foamed cement; and casting the slurry of foamed cement and leave it to set.

A process for the production of a mineral foam includes separately preparing a slurry of cement and an aqueous foam, wherein the cement slurry includes water and Portland cement as well as calcium silicate hydrate crystallization seeds; contacting the slurry of cement with the aqueous foam to obtain a slurry of foamed cement; and casting the slurry of foamed cement and leave it to set.

A no bake process is provided for preparing a foundry shape. A major amount of an appropriate foundry aggregate, especially a sand that has been mechanically-reclaimed, is mixed with an amount of halloysite tubes. A binder system, especially a water-based binder, such as an aqueous alkaline phenolic resole resin, is added to the mixed aggregate and halloysite, and a liquid co-reactant for curing the binder is also added. By intimately mixing the components, a foundry molding compound is formed and it can be placed into a mold or patter to cure into a foundry shape. When removed from the mold or pattern, the foundry shape can be used to cast molten metal.

Disclosed is a CO.sub.2 solidified fiber cement board and its preparation method. The matrix composition of the fiber cement board prepared in this disclosure is calcium carbonate, which has high compactness, and the crystal form of calcium carbonate is adjusted by adding shell powder to improve the toughness of the matrix, so that the fiber cement board has excellent mechanics and durability performance. In addition, the preparation process does not require high temperature maintenance, and has the characteristics of normal temperature preparation, which creates conditions for the introduction of organic synthetic fibers, so that the organic synthetic fibers can further improve the brittleness of cement fiberboard. While reducing energy consumption, the preparation process can also effectively solve the problem that excessive pressure is easily generated in the fiberboard under high temperature conditions in the existing high-temperature and high-pressure curing process.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing recycled concrete aggregate (RCA). One of the methods includes obtaining first optical measurements of RCA particles as the RCA particles are conveyed past the first optical sensors; determining, based on the first measurements, an initial characterization of the RCA particles; iteratively performing a carbonation process on the RCA particles, obtaining second optical measurements of the RCA particles, and determining, from the second measurements, a second characterization of the RCA particles, wherein conditions of the carbonation process are initially set based on the initial characterization, and the conditions of the carbonation process are adjusted based on the second characterization; ceasing the iterative performance of the carbonation process in response to the second characterization meeting target carbonation characteristics; iteratively performing a densification process on the RCA particles, obtaining third optical measurements of the RCA particles, and determining, from the third measurements, a third characterization of the RCA particles, wherein conditions of the densification process are initially set based on the initial characterization or the second characterization, and the conditions of the densification process are adjusted based on the third characterization; and ceasing the iterative performance of the densification process in response to the third characterization meeting target densification characteristics.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing recycled concrete aggregate (RCA). One of the methods includes obtaining first optical measurements of RCA particles as the RCA particles are conveyed past the first optical sensors; determining, based on the first measurements, an initial characterization of the RCA particles; iteratively performing a carbonation process on the RCA particles, obtaining second optical measurements of the RCA particles, and determining, from the second measurements, a second characterization of the RCA particles, wherein conditions of the carbonation process are initially set based on the initial characterization, and the conditions of the carbonation process are adjusted based on the second characterization; ceasing the iterative performance of the carbonation process in response to the second characterization meeting target carbonation characteristics; iteratively performing a densification process on the RCA particles, obtaining third optical measurements of the RCA particles, and determining, from the third measurements, a third characterization of the RCA particles, wherein conditions of the densification process are initially set based on the initial characterization or the second characterization, and the conditions of the densification process are adjusted based on the third characterization; and ceasing the iterative performance of the densification process in response to the third characterization meeting target densification characteristics.

Present invention teaches using MGO (magnesium oxide) materials, with the formula of the ingredients as disclosed to create a paste of slurry mixture. A molding and curing process is done by placing a layer of alkaline fiber in a mold with repeated application of the slurry mixture. Additional surface treatment, after hardening/curing, can be done to create surface decorative features, using environmentally friendly water-based coating, to suit clients’ specification.

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.