A three-dimensional printing head including a dynamic mixer comprising a mixer casing, which delimits a mixing chamber, a supply inlet configured to supply the mixing chamber with a mineral composition and a discharge outlet; and an injector for injecting a building material admixture in the mixing chamber. The injector includes a tubular injecting member being flexible and having an injection outlet, the tubular injecting member being elastically deformable between a first state in which the tubular injecting member is configured to allow a flow of the building material admixture through the tubular injecting member and towards the injection outlet, and a second state in which the tubular injecting member is configured to prevent a flow of the mineral composition from the mixing chamber and through the tubular injecting member.

A mixer (1) comprises a drum (2) having at least one inlet (6) and one outlet (7). The mixer (1) furthermore comprises a drive (3) and a stirring shaft (4), which is arranged in the drum (2) and is coupled to the drive (3). Furthermore, the mixer (1) comprises a conveying device (5), which is arranged in the drum (2) and which is arranged on one and the same axis as the stirring shaft (4).

A method in which a stream of dry cementitious powder from a dry powder feeder passes through a dry cementitious powder inlet conduit to feed a first feed section of a fiber-slurry mixer. An aqueous medium stream passes through at least one aqueous medium stream conduit to feed a first mixing section the fiber-slurry mixer. A stream of reinforcing fibers passes from a fiber feeder through a reinforcing fibers stream conduit to feed a second mixing section of the fiber-slurry mixer. The stream of dry cementitious powder, aqueous medium stream, and stream of reinforcing fibers combine in the fiber-slurry mixer to make a stream of fiber-cement mixture which discharges through a discharge conduit at a downstream end of the mixer.

Continuous method including: mixing water and cementitous powder to form slurry; mixing the slurry and reinforcement fibers in a single pass horizontal continuous mixer to form fiber-slurry mixture, the mixer including an elongated mixing chamber having a reinforcement fiber inlet port, and upstream of the fiber inlet port is an inlet port to introduce water and cementitous powder together as one stream or at least two inlet ports to introduce water and dry cementitous powder separately as separate streams into the chamber, a rotating horizontal shaft/s within the chamber, part of the chamber for mixing the fibers and slurry and moving the fiber-slurry mixture to a mixture outlet; discharging the fiber-slurry mixture from the mixer outlet; forming and setting the fiber-slurry mixture on a moving surface; cutting the set mixture into fiber reinforced concrete panels and removing the panels from the moving surface.

A method in which a stream of dry cementitious powder passes through a first conduit and aqueous medium stream passes through a second conduit to feed a slurry mixer to make cementitious slurry. The cementitious slurry passes through a third conduit and a reinforcement fiber stream passes through a fourth conduit to feed a fiber-slurry mixer which mixes the slurry and discrete fibers to make a stream of fiber-slurry mixture. An apparatus for performing the method is also disclosed.

A three-dimensional printing head including a dynamic mixer comprising a mixer casing, which delimits a mixing chamber, a supply inlet configured to supply the mixing chamber with a mineral composition and a discharge outlet; and an injector for injecting a building material admixture in the mixing chamber. The injector includes a tubular injecting member being flexible and having an injection outlet, the tubular injecting member being elastically deformable between a first state in which the tubular injecting member is configured to allow a flow of the building material admixture through the tubular injecting member and towards the injection outlet, and a second state in which the tubular injecting member is configured to prevent a flow of the mineral composition from the mixing chamber and through the tubular injecting member.

A mixer (1) comprises a drum (2) having at least one inlet (6) and one outlet (7). The mixer (1) furthermore comprises a drive (3) and a stirring shaft (4), which is arranged in the drum (2) and is coupled to the drive (3). Furthermore, the mixer (1) comprises a conveying device (5), which is arranged in the drum (2) and which is arranged on one and the same axis as the stirring shaft (4).