This application relates to a method of manufacturing a load-bearing hemp shiv concrete blocks using magnesium-based cement, the method including: measuring proportional parts of ingredients: a hemp shiv in 70-75% proportion by volume; a Magnesium Oxychloride Cement (MOC) in 20-25% proportion by volume; and water in 5-10% proportion by volume. The method includes depositing the measured ingredients in a mixer and mixing for a time period appropriate to the conditions to produce a slurry, wherein the time period is between ten minutes and thirty minutes; removing the slurry from the mixer; depositing the slurry into one or more molds comprising a frame with a lockable lid and a removable base; pressing, via a press, the slurry in the molds to a suitable level; allowing the pressed slurry to set and cure within the sealed molds to produce one or more load-bearing fiber based concrete blocks; removing the one or more load-bearing hemp shiv concrete blocks from the one or more molds by removing the lid of the molds.

A process for the formation of highly durable cementitious board using lightweight aggregate is disclosed. The process comprises pouring a core mix onto a conveyor, wherein the core mix is comprised of one or more lightweight aggregate filler in the amount of 0.5 to 5 weight percent of the core mix, one or more binders in the amount of 35 to 75 weight percent of the core mix, rheological admixture in the amount of about 0.5 to 5 weight percent of the core mix, surfactant in the amount of 0 to 0.1 weight percent of the core mix, one or more normal weight aggregate filler in the amount of 5 to 50 weight percent of the core mix, and water in the amount of 5 to 20 weight percent of the core mix. The process further comprises passing the core mix under a screed roller to flatten the core mix to produce an extruding board with a desired thickness.

Conductive concrete mixtures are described that are configured to provide EMP shielding and reflect and/or absorb, for instance, EM waves propagating through the conductive concrete mixture. The conductive concrete mixtures include cement, water, conductive carbon material, magnetic material, and metallic conductive material. The conductive carbon material may include conductive carbon particles, conductive carbon powder, and/or coke breeze. The metallic conductive material may include steel fibers, and the magnetic material may include taconite. The conductive concrete mixture may also include supplementary cementitious materials (SCM). A method of making a concrete structure includes pouring a concrete mixture to form conductive concrete, and positioning a first conductive screen within the conductive concrete proximate to an exterior surface of the conductive concrete. The method also includes positioning a second conductive screen within the conductive concrete in electrical contact with the first conductive screen.

The present invention relates to fiber cement products comprising a first layer, which first layer is covered by at least one second layer, characterized in that said first layer is the top layer and the first layer material has a density of between about 0.4 and about 0.9 g/cm.sup.3 inclusive, and at least comprises cement and between 1 wt % and 70 wt % (relative to the total dry weight of said first layer material) of a lightweight filler, and said at least one second layer is the bottom layer and covers only one of the main surfaces of the first layer, thereby forming a bi-layered fiber cement product, wherein the second layer material has a density of between about 0.9 and about 1.4 g/cm.sup.3 inclusive, and at least comprises fibers and cement.

The invention relates to a panel and a method for producing a panel. The panel is in particular a floor, wall or ceiling panel, and comprises at least one core layer, the core layer comprising an upper core surface and a lower core surface and at least one pair of opposite side edges; wherein the core layer comprises magnesium oxide cement; wherein the core has a density which is substantially homogenous over its entire volume, and wherein at least one decorative top layer is attached to an upper core surface of the core layer.

This application relates to a method of manufacturing a load-bearing hemp shiv concrete blocks using magnesium-based cement, the method including: measuring proportional parts of ingredients: a hemp shiv in 70-75% proportion by volume; a Magnesium Oxychloride Cement (MOC) in 20-25% proportion by volume; and water in 5-10% proportion by volume. The method includes depositing the measured ingredients in a mixer and mixing for a time period appropriate to the conditions to produce a slurry, wherein the time period is between ten minutes and thirty minutes; removing the slurry from the mixer; depositing the slurry into one or more molds comprising a frame with a lockable lid and a removable base; pressing, via a press, the slurry in the molds to a suitable level; allowing the pressed slurry to set and cure within the sealed molds to produce one or more load-bearing fiber based concrete blocks; removing the one or more load-bearing hemp shiv concrete blocks from the one or more molds by removing the lid of the molds.

The present invention relates to fiber cement products comprising an inner core material, which inner core material is covered by at least one outer surface layer, characterized in that:said inner core material has a density of between about 0.4 and about 0.9 g/cm.sup.3 inclusive, and at least comprises cement and between 1 wt % and 70 wt % (with respect to the total dry weight of said inner core material) of a lightweight filler, andsaid at least one outer surface layer has a density of between about 0.9 and about 1.4 g/cm.sup.3 inclusive, and at least comprises fibers and cement.

Disclosed is a composite gypsum board comprising a set gypsum core disposed between face (e.g., Manila) and back (e.g., Newsline) cover sheets. The set gypsum core is formed from a core slurry comprising stucco, water, and optional additives, such as foaming agent, migrating starch, accelerator, retarder, dispersant, etc. A dense layer formed from a dense layer slurry comprising stucco, water, fiber (e.g., paper fiber), and optionally, strength-enhancing starch, is disposed between the core and the face paper. The dense layer slurry contains a greater concentration of fiber, and optionally, strength-enhancing starch, than the core slurry, but the concentration of one or more other additives (e.g., accelerator, retarder, dispersant, or combinations thereof) is lower or the same in the dense slurry as compared with the core slurry. Also disclosed is a method of making board using one board mixer. In embodiments, paper fiber is added to water to form a suspension. The suspension is introduced, while in a non-laminar state, into the dense slurry. Further disclosed is apparatus, such as an extractor and an additive injection system, which can be a part of a cementitious slurry mixing and dispensing assembly.

The present invention relates to fiber cement products comprising an inner core material, which inner core material is covered by at least one outer surface layer, characterized in that: said inner core material has a density of between about 0.4 and about 0.9 g/cm.sup.3 inclusive, and at least comprises cement and between 1 wt % and 70 wt % (with respect to the total dry weight of said inner core material) of a lightweight filler, and said at least one outer surface layer has a density of between about 0.9 and about 1.4 g/cm.sup.3 inclusive, and at least comprises fibers and cement.

A vegetal concrete masonry unit is provided which comprises cooked crop residues, binder and pulverized fuel ash in a mass ratio of 1:1:1.5 to 1:1.5:3.