Abstract:
A method in which a stream (5) of dry cementitious powder passes through a first conduit and aqueous medium stream (7) passes through a second conduit to feed a slurry mixer (2) to make cementitious slurry (31). The cementitious slurry (31) passes through a third conduit and a reinforcement fiber stream (34) passes through a fourth conduit to feed a fiber-slurry mixer (32) which mixes the slurry (31) and discrete fibers to make a stream of fiber-slurry mixture (36). An apparatus for performing the method is also disclosed.
Abstract:
A method for making geopolymer cementitious binder compositions for cementitious products such as concrete, precast construction elements and panels, mortar and repair materials, and the like is disclosed. The geopolymer cementitious compositions of some embodiments are made by mixing a synergistic mixture of thermally activated aluminosilicate mineral, calcium aluminate cement, a calcium sulfate and a chemical activator with water
Abstract:
A process for making a fiber reinforced cementitious product such as a panel which hardens to an ultra-high compressive strength composite for use in making panels with ballistic and blast resistant properties. The panel has a continuous phase resulting from curing an aqueous mixture, in the absence of silica flour, of inorganic cement binder, inorganic mineral filler having a particle size of about 150-450 microns, pozzolanic mineral filler, and polycarboxylate based superplasticizer self-leveling agent, and water. The mixture may also include alkanolamine and acid or acid salt. The continuous phase may be reinforced with fiber distributed in the continuous phase before curing to form a panel. The panel may be reinforced with a fiber reinforced skin attached to at least one surface of the core, e.g., by lamination with an adhesive, e.g., epoxy, to form a ballistic and blast resistant cementitious armor panel.
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:
An embedment device for use in a cementitious panel production line wherein hydraulic cement slurry is transported on a moving web on a support frame, and chopped fibers are deposited upon the slurry. The device includes as one embodiment, a wire grid structure mounted on a reciprocating shaft driven by a piston which moves the grid down into the slurry and then up out of the slurry transverse of the travel of the slurry layer on the web. An alternative embodiment includes a grid cell structure with thin walls extending upward from the grid surface in contact with the slurry moved up and down in a reciprocating motion transverse of the travel of the slurry layer on the web. The intermeshing relationship of the grid cell with the fiber and slurry enhances embedding the fibers into the slurry and prevents device clogging by fibers and prematurely set slurry particles.
Abstract:
In a preferred embodiment, a membrane for use as an underlayment includes a basemat, which includes at least three plies, a ply of a meltblown polymer sandwiched between two plies of spunbond polymer; and a flexible coating applied to the basemat, the coating having a cementitious hydraulic component, a polymer comprising a water-soluble, film -forming polymer; and water. The finished membrane is flexible. Another embodiment for an underlayment for use underneath ceramic tiles includes a basemat and a coating of a set hydraulic component less than 1/8 inches thick.
Abstract:
A cementitious board system which is reinforced on its opposed surfaces by an improved glass fiber mesh scrim with thicker yarn and larger mesh openings to provide a cementitious board with improved handling properties while retaining tensile strength and long term durability. The fabric is constructed as a mesh of high modulus strands of bundled glass fibers encapsulated by alkali and water resistant material, e.g. a thermoplastic material. The composite fabric also has suitable physical characteristics for embedment within the cement matrix of the panels or boards closely adjacent the opposed faces thereof. The fabric provides a board system with long- lasting, high strength tensile reinforcement and improved handling properties regardless of their spatial orientation during handling. Also included are methods for making the reinforced board.
Abstract:
A self-leveling cementitious mixture with excellent flow properties and which hardens with a controlled rate of strength development to an ultra-high compressive strength composite composition for use in making articles such as cementitious armor panel with ballistic and blast resistant properties including: a continuous phase resulting from the curing of an aqueous mixture, in the absence of silica flour, of inorganic cement binder, inorganic mineral filler having a particle size of about 150-450 microns, pozzolanic mineral filler, polycarboxylate based self-leveling agent and water. The cementitious mixture may include alkanolamine, such as thethanolamine, and acid or acid salt, such as tartaric acid. The cementitious composition may be reinforced with reinforcing fibers, e.g. glass fibers, in an amount of about 0.5 - 6.0 % by volume of the overall cementitious composition. The fibers are uniformly dispersed in the cementitious composition before it is cured to form a final cementitious armor panel.
Abstract:
A process employing a wet mixer having a vertical mixing chamber for forming a wet slurry of a cementitious powder and liquid. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feed means for supply of cementitious powder and water to the slurry mixing area of the chamber is also disclosed.
Abstract:
A composition for making flexible articles includes a hydraulic component of at least 50 weight % fly ash, a water-soluble, film-forming polymer and water. Articles are made from this composition by making a slurry of the components, forming the article and allowing it to set.