A method for producing a three-dimensional construction material component preferably having at least one curved surface. A plurality of spacers are arranged in a formwork. A textile reinforcement is supported on the spacers, such that the textile reinforcement has a defined position within a formwork interior of the formwork. A tensile force is applied via a tensioning device to the textile reinforcement in at least one tension direction. Construction material is introduced into the formwork interior and surrounds the textile reinforcement. The construction material is then hardened, wherein the tensile force is maintained during the hardening. During this process, the spacers are integrated into the construction material component. The tensioning device has at least one clamping unit for clamping an end portion of the textile reinforcement between two clamping surfaces. The clamping surfaces are provided on clamping insert bodies, which are of a plastic material of a defined hardness.

The invention relates to a prestressed concrete body, containing prestressed filament yarns based on cellulose and/or cellulose derivatives. Advantageously, said prestressed concrete body is produced in that: 1.) filament yarns based on cellulose and/or derivatives thereof are clamped into a shaping container, 2.) the clamped filament yarns are wetted with water to make them swell, 3.) a prestress of approximately 0.5 to 10.0 kg/4000 dtex is applied to the wetted filament yarns, 4.) liquid concrete is poured into the shaping container containing the prestressed filament yarns, 5.) the liquid concrete in the shaping container is cured to form precast concrete, maintaining the specified applied prestress. Useful application possibilities are opened up by the invention. Use as components or structural elements with low brittleness and/or high resistance to corrosion, especially in bridge building, especially in bridge girders, in constructing containers, in constructing high-rise structures, in the production of hollow floors or ceilings, hollow core planks, precast floors or ceilings and for recycling once the service life has passed by being ground into concrete granules is advantageous.

A pre-compression system for pre-compressing a concrete structure, the system comprising a first tubular element (31) that is expandable in a longitudinal direction and interposed between the first and the second head (21, 22). The first tubular element (31) is movable between a longitudinally elongated configuration, in which a pressurized fluid is placed inside the first tubular element (31), and a contracted configuration, in which said fluid is at least partly removed, the passage from the elongated configuration to the contracted configuration bringing about a compression on the concrete which at least partly envelops the first tubular element (31).

According to the method, at least one carbon fibre-reinforced polymer band is joined to the steel structure at the end regions thereof, capable of transferring tensile forces. Subsequently, at least one lifting element (7) disposed between the carbon fibre-reinforced polymer band (4) and the steel girder (3) to be reinforced in a region between these end anchorages (5), is extended substantially perpendicular to the carbon fibre-reinforced polymer band (4). So, a tensile force stress is generated between the end regions of the carbon fibre-reinforced polymer band (4). Then, a steel girder treated in such a manner includes at least one carbon fibre-reinforced polymer band, which is each joined to the steel structure (1) at the end regions thereof, capable of transferring tensile forces. In the region between these end regions, a lifting element (7) is disposed between the carbon fibre-reinforced polymer band (4) and the steel girder (3) to be reinforced, by means of which the carbon fibre-reinforced polymer band (4) is subjected to tensile stress by lifting away from the steel girder (3). The tensile force is transferred to the steel girder (3) via the anchoring elements (5).

An anchor system for fiber reinforced polymer (FRP) material having an outer casing including a linear inner profile portion; and a non-linear inner profile portion, both on an inner surface of the outer casing. The anchor further having a wedge configured to be housed by the inner profile of the outer casing, the wedge including: a linear outer profile portion configured to mate with the linear inner profile portion of the outer casing; a non-linear outer profile portion configured to mate with the non-linear inner portion of the outer casing, both on the outer surface of the wedge; and an inner gap formed in the wedge and configured to receive the FRP material.

The present invention provides an early warning device and a ductility control method for a prestressed FRP reinforced structure. By setting a tensioning screw, prestressed reinforcement can be converted into non-prestressed reinforcement when tensioning screw failure occurs, and the structure is still in a safe state. This can improve the bearing capacity and ductility of the reinforced structure, while the ductility can be controlled and designed, thereby resolving the problem of easy disconnection and brittle failure between the FRP and anchors, and greatly improving FRP utilization and structural safety.

Prestressed carbon fibers of at least one textile structure comprising carbon fibers are embedded in a concrete matrix. At least one textile structure comprising carbon fiber bundles is laid in a mold at a distance from one another, into two accommodation elements which are arranged at two diametrical end faces of the mold. Hollow spaces within the accommodation element are filled with a rapid-curing viscous composition having a mineral basis or rapid-curing polymer. After curing the composition or of the polymer, tensile forces act on the accommodation element(s) in the longitudinal direction of the carbon fiber bundles with a tensioning device. During the tensile force the interior of the mold is subsequently filled completely with viscous concrete. After curing of the concrete, the tensile forces on the prestressed carbon fiber bundles are largely transferred to the cured concrete and the concrete component can then be removed from the mold.

Two lengths of FRP rebar are formed into spirals and coupled at cross over locations to form a structure to be embedded into a cementitious material or covered in a cementitious material for repairing a form or in new construction.

In an anchorage (1) of continuous fiber-reinforced polymer (CFRP) strands that anchors continuous fiber-reinforced polymer strands (2) to concrete structures, there is provided an untwisted diameter-expanded portion (3) expanded to a diameter D2 by being radially expanded with respect to a diameter D1 of a general portion (4) of the CFRP strands (2) by untwisting any section of the CFRP strands (2) formed by stranding a plurality of element wires (20, 21) that are bundles of multiple continuous fibers, and filling and curing a time curable material (5) in a clearance among the element wires the untwisted section that is untwisted.

A pre-compression system for pre-compressing a concrete structure, the system comprising a first tubular element (31) that is expandable in a longitudinal direction and interposed between the first and the second head (21, 22). The first tubular element (31) is movable between a longitudinally elongated configuration, in which a pressurized fluid is placed inside the first tubular element (31), and a contracted configuration, in which said fluid is at least partly removed, the passage from the elongated configuration to the contracted configuration bringing about a compression on the concrete which at least partly envelops the first tubular element (31).