The invention relates to a method for layer-by-layer deposition of concrete by providing extrudable concrete. A first flow comprising a binder material and water and a second flow comprising a carrier material, an additional component and water are mixed in a static mixer to form a third flow of extrudable concrete. The material of the second flow has a shorter initial setting time than the material of the first flow. The first flow has a first viscosity V1 and the second flow has a second viscosity V2 so that the ratio V1/V2 ranges between 1/40 and 40. The third flow has a viscosity larger than the viscosity of the first flow and the second flow and a yield stress larger than the yield stress of the first flow and the second flow. The material of the third flow has an initial setting time shorter than initial setting time of the first flow.

The invention further relates to a system to extrude concrete, in particular for layer-by-layer deposition of concrete.

A shotcrete nozzle assembly comprising: a tubular body operatively connectable to a concrete source, the tubular body including a stream controlling section for controlling a stream of fresh concrete projected from an outlet body end, the stream controlling section including at least one helicoidal conduit defined within the body sidewall, each helicoidal conduit extending helicoidally around a central conduit between an air inlet end operatively connectable to a pressurized air source and an air outlet end located towards the outlet body end, each helicoidal conduit being twisted around the central passageway to guide pressurized air exiting through the air outlet end along an helicoidal path extending away from the outlet body end and around the stream of fresh concrete exiting the outlet body end.

Disclosed is a method and system for blending a foam modifier with foaming agent on-line, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

Cellular concrete is formed from a cement-based wet mix slurry with a foam entrained into the wet mix. The foam is created using a foaming agent, mixed with water and air using a foam generator. The wet mix is mixed with the foam to form the cellular concrete wet mix. Poor component metering and blending practices in the current state of the art limits the performance capabilities of existing cellular concrete placements. The presently disclosed technology addresses this with a cellular concrete mixing system comprising a dry mix hopper to store a quantity of dry mix, a mixing tank to blend the dry mix and water together to form a wet mix, a holding tank to store a quantity of the wet mix, a foam generator to generate foam from air, water, and foam concentrate, and a blend controller to control operation of the overall mixing system.

A shotcrete nozzle assembly comprising: a tubular body including a body sidewall defining a central passageway extending along a central longitudinal passageway axis, and water dispensing bores extending through the body sidewall and including: first and second sets of water dispensing bores positioned such that outlet openings thereof defined in an inner face of the body sidewall are disposed in a respective one of longitudinally spaced-apart first and second transversal planes extending perpendicularly to the passageway axis, at least some of the water dispensing bores being oriented such that the central bore axes thereof extend in a non-radial direction relative to the passageway axis, and such that an orthogonal projection of the central bore axes of the first and second sets of water dispensing bores onto one of the transversal planes forms first and second projected central bore axes which intersect each other at a first non-zero angle.

A device and method device for continuous mixing and laying of cementitious coating onto a substrate. There is a first mixing stage for metering and mixing a first liquid and a second liquid to create a first mix and a second mixing stage for metering and mixing the first mix with aggregate to form a second mix. The first and second mixing stages use flow meters and flow controllers for metering and restricting the flow of the first liquid, the second liquid and aggregate. A controller operatively coupled to the flow meters and flow controllers controls the mixing in a closed-feedback arrangement. A screed box applies the second mix onto the substrate to create a flooring layer. The flooring may be in a food processing plant.

Disclosed is a method and system for blending a foam modifier with foaming agent on-line, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

Disclosed is a method and system for blending a foam modifier with foaming agent online, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

A foam injection system for use in the manufacture of cementitious products includes a foam injection body and first and second port inserts. The foam injection body defines a slurry passageway and a port passageway having a port opening in fluid communication with the slurry passageway. The first and second port inserts respectively define first and second foam passageways having first and second orifice sizes. The first and second orifice sizes are different. The first and second port inserts are adapted to removably mount to the foam injection body such that the respective foam passageway is in fluid communication with the slurry passageway via the port opening of the port passageway. One port insert can be replaced with another to readily vary the pressure of the foam passing through the particular port insert and injected into a cementitious slurry traveling through the slurry passageway.

A device and method device for continuous mixing and laying of cementitious coating onto a substrate. There is a first mixing stage for metering and mixing a first liquid and a second liquid to create a first mix and a second mixing stage for metering and mixing the first mix with aggregate to form a second mix. The first and second mixing stages use flow meters and flow controllers for metering and restricting the flow of the first liquid, the second liquid and aggregate. A controller operatively coupled to the flow meters and flow controllers controls the mixing in a closed-feedback arrangement. A screed box applies the second mix onto the substrate to create a flooring layer. The flooring may be in a food processing plant.