A concrete slab, the slab containing conventional concrete and a combined reinforcement of both post-tension steel strands and fibers, said post-tension steel strandshaving a diameter ranging from 5 mm to 20 mm,having a tensile strength higher than 1700 MPa, said fibers being either steel fibers and being present in a dosage ranging from 5 kg/m.sup.3 to 90 kg/m.sup.3 or being macro-synthetic fibers and being present in a dosage ranging from 1.5 kg/m.sup.3 to 9.0 kg/m.sup.3, whereby the slab has upper as well as lower surfaces and sides, whereby further each strand or a group of strands has two ends, whereby further each strand or a group of strands is provided with end anchors on at least one of its ends, whereby the slab has at least one opening in its upper surface so that said anchor is accessible from said upper surface through said opening.

The present invention concerns a concrete slab, the slab comprising concrete and a combined reinforcement of both post-tension steel strands and fibers, said post-tension steel strandshaving a diameter ranging from 5 mm to 20 mm,having a tensile strength higher than 1700 MPa, said fibers being either steel fibers and being present in a dosage ranging from 10 kg/m.sup.3 to 75 kg/m.sup.3 or being macro-synthetic fibers and being present in a dosage ranging from 1.5 kg/m.sup.3 to 9,0 kg/m.sup.3, whereby the concrete is expanding concrete.

A concrete panel system includes first, second, and third rectangular precast concrete panels, each defining a respective top edge, bottom edge, and first and second lateral edges. A first type connector is formed in the concrete material at least along the top edge of the first panel and along the first lateral edge of the first panel. A second type connector is formed in the concrete material at least along the second lateral edge of the second panel, and along the bottom edge of the third panel. The first type connector and the second type connector are configured to connect together so as to form a cavity between the respective panel edges. This cavity extends along the first lateral edge of the first panel to facilitate positioning rebar between adjacent panels.

To provide a concrete-reinforcing shaped body containing concrete-reinforcing fibers and having a plate-like shape. The concrete-reinforcing fibers each preferably have a diameter of 0.3 mm smaller and a length of 5 mm or larger and 25 mm or smaller.

A composite building member such as a stud, joist or rafter. The composite building member includes a composite composition including concrete and wood fiber. In addition, a reinforcing structure is embedded into the composite structure. The reinforcing member comprises two elongated C-shaped channels and a plurality of ties interconnected between the C-shaped channels.

A masonry reinforced with at least one bed joint masonry reinforcement structure. The bed joint reinforcement structure includes at least two cords, which have metal filaments that are twisted together. The cords are oriented parallel or substantially parallel in the length direction of the masonry reinforcement structure.

Machines and system for 3D printing are disclosed. One machine includes a machine frame having a plurality of ground engaging elements to facilitate movement of the machine frame, a telescoping boom pivotably coupled to the machine frame and configured to pivot along at least a horizontal plane, a material line coupled to the boom and configured to convey a material therethrough, a printhead coupled to the boom and in fluid communication with the material line to receive the material and to dispense the material, and a controller configured to receive 3D printing information and to convert the 3D printing information into positional coordinates of the printhead, wherein the controller is to cause movement of the boom to position the printhead based at least on the position coordinates.

A masonry reinforced with at least one bed joint masonry reinforcement structure. The bed joint reinforcement structure includes at least two cords, which have metal filaments that are twisted together. The cords are oriented parallel or substantially parallel in the length direction of the masonry reinforcement structure.

A concrete panel system includes first, second, and third rectangular precast concrete panels, each defining a respective top edge, bottom edge, and first and second lateral edges. A first type connector is formed in the concrete material at least along the top edge of the first panel and along the first lateral edge of the first panel. A second type connector is formed in the concrete material at least along the second lateral edge of the second panel, and along the bottom edge of the third panel. The first type connector and the second type connector are configured to connect together so as to form a cavity between the respective panel edges. This cavity extends along the first lateral edge of the first panel to facilitate positioning rebar between adjacent panels.

A method of making steel fibers, preferably for use as a concrete additive, and for the supply thereof in making steel fiber concrete, characterized in that to form the steel fibers (2) first a sheet-metal strip (1) is notched either on one face or both faces so as to form steel-fiber wires (4) that are initially connected together by webs (5), and that further, for subsequently converting the webs (5) into thin easily mutually separable separation webs forming separation surfaces that are fracture-rough and low in burring upon separation, the steel-fiber strip is subjected to a flexing process in which each web (5) is subjected to multiple bending deformations about its longitudinal axis in such a way that incipient cracks are produced at the webs (5) due to fatigue fracture and thus the separation webs are produced.