EP2912239A1 - Reinforcing element for producing prestressed concrete components, concrete component and production methods - Google Patents

Abstract

The present invention relates to a reinforcing element (10) for producing prestressed concrete components, a concrete component and corresponding production methods. The reinforcing element (10) comprises a plurality of fibers (12) and a plurality of holding elements (14) which are connected to each other by the fibers (12) so that the fibers (12) can be stressed in their longitudinal direction (T) by means of the holding elements (14). The fibers (12) are fixed to the holding elements (14) in such a way that the fibers (12) in the stressed state lead in a largely linear manner into the holding elements (14). This enables both a high degree of pretension and an efficient, reliable and thus cost-effective production of the concrete components.

Description

Reinforcing element for producing prestressed concrete components, concrete component and Hersteilverfahren

The present invention relates to a reinforcing element for producing prestressed concrete components. Further

The invention relates to a prestressed concrete component and method for producing the reinforcing element and the

prestressed concrete component. Prestressed concrete slabs are known from the prior art. For example, US 2002/0059768 Al discloses a method for producing a prestressed concrete slab by means of tensioned wire ropes. To generate the voltage, the wire ropes are wound around respective opposing bolts and then by moving apart of the

Bolt under tension. This results in a preload of about 70% of the breaking stress of the wire ropes.

The object of the present invention is to provide an improved reinforcing element for the production

prestressed concrete components, an improved concrete component and improved manufacturing methods for the reinforcing element and the prestressed concrete component specify.

This object is achieved by a reinforcing element with the features of claim 1 and a concrete component and manufacturing method according to the accompanying claims. Further embodiments according to the invention are specified in the further claims.

Furthermore, the present invention relates to a

Reinforcing element for producing prestressed

 Concrete members, comprising a plurality of fibers and a plurality of support members passing through the fibers

are connected so that the fibers by means of

Holding elements can be stretched in their longitudinal direction. In this case, the fibers are fastened to the holding elements in such a way that, in the tensioned state, the fibers open substantially in a straight line into the holding elements. This will provide both high preload and efficient,

reliable and therefore cost-effective production of

Concrete components achieved.

The term "fiber" includes both a single or multiple elongate and flexible reinforcing elements for

Concrete components, for example a single filament - also called monofilament or monofilament - or a bundle of filaments - also multifilament, multifilament, yarn or - in stretched filaments - called roving. In particular, the term fiber also includes a single wire or multiple wires. Furthermore, the fibers may also be coated individually or jointly and / or the fiber bundle may be stranded or twisted. In one example, the net cross-sectional area is the

Fibers (ie without resin impregnation) smaller than about 5 mm ² and is in particular in a range of about 0.1 mm ² to about 1 mm ² . In another example, the elastic extensibility of the fibers is greater than about 1%. In another example, the tensile strength of the fibers, based on their net cross-sectional area, is greater than about 1000 N / mm ² , in particular greater than about 1800 N / mm ² .

In the production of a prestressed concrete component, for example, the inventive first

Arming elements laid in a mold and then the fibers by pulling the corresponding

Holding elements stretched. Subsequently, the concrete component is poured, wherein the lying inside the mold parts of the fibers are cast in concrete. After hardening of the

Concrete is dissolved before the voltage applied to the fibers, whereby the tension is maintained in the concreted parts of the fibers, since the concreted

Fiber parts are non-positively connected to the concrete and virtually no relative shift between them

Fiber parts and the concrete takes place. The non-positive connection is based - among other things - on the

Wedging of the fibers in their concrete casing (Hoyer effect). The tension-free parts of the fibers projecting from the concrete component can be separated off and removed together with the retaining elements. In the preloaded

Concrete component is therefore the bias through the

Creates tension of the embedded fibers. The connection of fibers and concrete can with

be reinforced various means, for example, with an increased surface roughness of the fibers. In one example, this connection is designed in such a way that over the mechanical thrust connection after 200 mm, in particular after 100 mm, further, in particular 70 mm, insertion length (i.e., concreting length of the fibers) the full

Dimensioning tensile force can be transmitted.

The fibers of the reinforcing element according to the invention can be produced from a multiplicity of different materials, in particular from non-corrosive materials

Material and more particularly made of alkali-resistant material. For example, this material is a polymer such as carbon but also glass, steel or natural fiber.

For example, the fibers are made of carbon.

Carbon fibers have the advantage that they are very durable, which means that even over decades are no

Significant losses of strength detected. In addition, carbon fibers are corrosion resistant, in particular they do not corrode on the surface of the concrete components, and are virtually invisible. Thus, the carbon fibers can often be left on the surface of the concrete components. But they can also be removed with ease, for example by canceling or simply stripping off. The attachment of the fibers "in" the holding elements comprises a variety of mounting possible, in particular the attachment of the fibers "on" or "on" the holding elements, for example, a lamination of the fibers without further coverage.

Surprisingly, the solution according to the invention achieves both high prestressing of the concrete components and efficient, reliable and simple handling of the reinforcing elements. This allows the

Concrete components are made particularly inexpensive. In particular, the following is achieved:

Due to the largely straight-line opening of the fibers with respect to their longitudinal direction, ie the uniform continuation of the fibers in the holding elements, transverse stresses in the fibers are largely avoided. Such transverse stresses often lead to fiber breaks and occur for example in kinks, congestion or narrow

 Curve radii, so typically deflecting webs, pulleys or guide pins. thanks to the

inventive fastening of the fibers with the good introduction of the acting forces in the holding element can be achieved without increasing the risk of breakage, a high tensile force and thus a high bias of the concrete components. This is particularly advantageous in the case of carbon fibers, in particular in the case of impregnated carbon fibers, since these are particularly susceptible to breakage with respect to transverse stresses. In one example, the fibers, in particular the

Carbon fibers, with a tension of about 50% to about 95% of the breaking stress of the fibers are stretched. In another example, the fibers may have at least about 80%, more preferably at least about 90%, of the ultimate stress of the

Fibers are stretched. This is a cost-effective production of very stable, large and thin

Concrete components achieved. A high bias of the

Concrete components is particularly advantageous in carbon fibers, since carbon fibers have a different expansion behavior than concrete.

Thanks to the reinforcing elements according to the invention, it is possible to produce large and thin concrete components which practically do not bend under load. In one example, the thickness of the concrete component to be produced is in the range of about 10 mm to 60 mm, in particular about 15 mm to 40 mm. In another example, the

areal extent of the concrete component at least approximately 10 m × 5 m, in particular at least approximately 10 m × 10 m, more particularly at least approximately 15 m × 15 m. In another example, the length of the concrete component is at least about 6 m, more particularly at least about 12 m.

Furthermore, the reinforcing elements can be produced as intermediate products at a first location, optionally packed in corresponding transport containers, and transported to another location for producing the concrete parts become. In the other place, for example in one

Concrete manufacturing plant, then stand the delivered

Reinforcement directly as prefabricated components available.

Furthermore, by the inventive compound of the fibers with the holding elements a robust and

Space-saving and thus a well transportable unit achieved.

In one embodiment of the present invention, the fibers are individual fibers and / or comprise one or more rovings, in particular carbon rovings. This makes the production of particularly stable and lightweight

Concrete components achieved. Individual fibers are to be understood as meaning individual, not directly connected fibers. In contrast, is an ongoing

To see fiber assembly, in which the reciprocating parts of the fiber assembly are connected via loops.

The term "roving" is understood to mean a bundle of elongated filaments. Such roving, also referred to as drawn yarn, typically includes several thousand filaments, in particular about 2000 to about 16 ^Λ 000 filaments. By roving the tensile forces acting on the fibers are largely uniformly distributed over a plurality of filaments, so that local

Peak loads are largely avoided. Furthermore, the filaments of the roving have a small

Fiber diameter, so that a correspondingly large surface-diameter ratio and thus a good bond between the concrete and the filaments is achieved. Furthermore, a good shear transfer and a good distribution of tensile load on the concrete can be achieved.

In one example, the fibers are made from an array of multiple rovings comprising 2 to 10, especially 2 to 5, individual rovings. Thus, they have

Fibers about 4,000 to about 160 ^Λ 0000 filaments.

In one embodiment of the present invention, the holding elements have guide elements for the fibers, in particular a clamping device and / or a carrier for laminating the fibers in the end region, in particular a fiber-reinforced polymer matrix, more particularly a polyester matrix. Through this management element, a good power transmission is achieved. In addition, laminating makes it a particularly space-saving, and robust

Unit reached. The holding elements can also as

Double adhesive tape be formed.

In one embodiment of the present invention, the fibers form a substantially planar position in the holding elements, and in particular are arranged substantially parallel to one another and / or substantially uniformly spaced from one another. As a result, the reinforcing element in the form of a track or a harp. This form is easy to stack or unroll, optionally using

Intermediate sheets for separating the respective fibers. As a result, reinforcing elements are easy to transport.

Such a harp-shaped reinforcing element has the advantage over a grid that no knots occur and thus very high tensile load can be achieved. In addition, eliminates complicated manufacturing steps such as weaving or braiding and there is high flexibility in terms of the width of the webs, since no machines are required for the production of a grid. Therefore, so-called "endless products" in both length and width can be easily produced.

In one embodiment of the present invention, the reinforcing element has additional spacers which connect the fibers to one another, for example in the form of transverse threads and / or a woven fabric, so that there is a spacing between the individual fibers even if the reinforcing element is not or only partially tensioned.

This will entangle the unstressed fibers

largely or completely prevented. These

Spacers thus serve as mounting aid and / or

Transport assistance. In concreted state, the spacers take virtually no tensile loads. In one embodiment of the present invention, the reinforcement spacing is approximately 5 mm to approximately 40 mm, in particular approximately 8 mm to approximately 25 mm, and / or respectively at least 10, in particular at least 40, fibers are fastened in the retention elements. For example, the Armierungsabstand, that is, the distance between two adjacent fibers, less than or equal to twice the thickness of the concrete component.

In one embodiment of the present invention, fibers with an alkali-resistant polymer, in particular:

with a resin, more especially with a

Vinylester resin, impregnated. This will make a higher

Tensile strength of the fibers achieved.

In one embodiment of the present invention, the fibers are coated with a granular material, in particular with sand. As a result, an improvement in the bond between fibers and concrete and thus a higher

Resistance of prestressing in the concrete component achieved.

In one embodiment of the present invention, the fibers are fastened to the holding elements in such a way that the fibers in the tensioned state continue largely in a straight line in the holding elements, in particular via one

Distance of at least about 5 mm, more preferably at least about 10 mm. This will be a good one

Power transmission between the fibers and the holding elements achieved. In one embodiment of the present invention, the holding elements have a force distribution means, in particular a curvature and / or a profiling, extending in particular transversely to the direction of the fibers.

 This results in a good distribution of the acting forces and thus a high tensile stress and / or a low

Loading of the fibers achieved during clamping.

In addition, a shortening of the integral length is achieved, ie a shortening of the required length for reliable attachment of the fibers to the holding elements.

In one example, the curvature of the holding element is designed such that the curved fibers each define layers arranged largely parallel, in particular perpendicular to the position of the fibers, planes. For example, if the fibers are arranged in a horizontal position, their fiber ends are curved vertically downwards or upwards.

In particular, the profiling is a good

achieved frictional connection between the retaining element and the clamping device. Thus, the pressure on the retaining element and / or on the fibers can be reduced. In one example, the profiling is arranged on at least one of those surfaces of the holding element which is provided for fastening the holding element in a clamping device. In another example, the Profiling wavy or jagged, in particular sawtooth.

In one embodiment of the inventive

Armierungselements whose width is greater than 0.4 m, in particular greater than 0.8 m, and / or whose length is greater than 4 m, in particular greater than 12 m. This achieves efficient production of large concrete components. For example, a 20 m x 20 m large

Concrete slab to be produced in a single work cycle.

Furthermore, the present invention relates to a method for producing a reinforcing element for prestressed concrete components, the method comprising the steps: - providing tensioned fibers by common

 Extracting a plurality of spaced-apart fibers; and

 - Attaching a retaining element to the tensioned fibers, in particular by clamping and / or laminating to fix the fibers in their mutual arrangement, in particular with respect to distance and / or orientation.

 This results in a largely parallel processing of the fibers and thus a very efficient production of the

Armierungselements and an advantageous arrangement of the fibers achieved, in particular also with regard to the further use of the reinforcing element, namely for the tensioning of the fibers before and during the Einbetonierens. In one example, after the connection with the fibers, the holding element is severed, in particular in the middle, so that the two parts produced in turn form two holding elements for two successively produced reinforcing elements. In this case, the first section forms the end of a first reinforcing element and the second section forms the beginning of the subsequent reinforcing element.

In another example, the holding element is designed as a double holding element, wherein between the two

Parts of the double-holding element is an open intermediate region in which the fibers are exposed. The above-mentioned severing of the holding element can be effected by a simple separation of the fibers in this intermediate region, for example by breaking. As a result, an efficient separation in the production, in particular in the series production, the reinforcing elements is achieved.

In one embodiment of the inventive method for producing the reinforcing element, the

 Attach the retaining element during the common

Extracting the fibers, in particular by moving the

Retaining element in synchronism with the movement of the fibers.

As a result, a very efficient production is achieved, in particular in the series production of

Reinforcement elements. In one embodiment of the inventive method for producing the reinforcing element, the

Attach the retaining element by attaching a

Upper part and a lower part of the retaining element from opposite sides of the fibers, in particular by the joining of glass fiber mats.

In a further embodiment of the inventive method for producing the reinforcing element, the fibers are arranged by laying the fibers on a first part of the holding element and fixing the fibers by adding a second part of the holding element and by compressing these two parts. As a result, the fibers are firmly enclosed by the retaining elements, so that a particularly strong and robust attachment is achieved.

Furthermore, the present invention relates to a prestressed concrete component, in particular a concrete slab using at least one inventive

 Reinforcing element was prepared, wherein the bias of the concrete component is at least 80%, in particular at least 90%, of the breaking stress of the fibers.

In one example, this concrete component is produced using a plurality of reinforcing elements according to the invention, arranged in groups in particular. The groupwise arrangement improves the fit achieved to the conditions of the concrete component. A

Grouping can be achieved by one or more horizontal and / or vertical distances or by an angular, in particular rectangular, arrangement.

In one example, the biasing of the fibers is accomplished by sectioning, in particular individually for each of the reinforcing elements used. This allows the preload flexible to specific requirements

be set.

In one example, the reinforcement spacing, i. of the

Distance between two adjacent fibers, less than or equal to twice the thickness of the concrete component, in particular less than or equal to twice the plate thickness.

Furthermore, the present invention relates to a method for producing a prestressed concrete component, the method comprising the steps:

- Providing at least one inventive

 Reinforcing element /

 - Tensioning of the fibers of the reinforcing element

 Pulling apart the associated holding elements; and

Concreting of the concrete component with at least partial concreting in of the tensioned fibers.

This makes very efficient and easy-to-use preparation work and thus a cost-effective Production of the concrete component achieved. In particular, no elaborate and complicated laying work of individual fibers, especially delicate braiding. Thus, the inventive method is very well suited for the manufacturing processes in a manufacturing plant for

Concrete components.

The inventive method is particularly suitable for the production of large prestressed concrete components, for example for concrete slabs of about 20 m wide and about 20 m in length. In a subsequent operation, these large prestressed concrete components can then be divided into smaller prestressed concrete components, as the

Preloading the concrete components while sharing is always maintained. The smaller concrete components can then be individually tailored, for example by sawing, CNC milling or water jet cutting, for example, specially shaped floor panels, stair treads or plates for

Make table tennis tables. Such a subdivision can - as described in more detail below - by

 Use of separating elements, in particular a foam can be achieved.

In a further embodiment of the inventive method for producing the prestressed concrete component, the provision of at least one

Armierungselements by arranging a plurality of

Armierungselemente in one layer, in particular by substantially parallel and / or adjacent To lay next to each other. This achieves efficient setup of large areas.

In a further embodiment of the inventive method for producing the prestressed concrete component, the provision of at least one

Armierungselements by arranging the reinforcing elements in at least two layers, wherein the alignment of the

Reinforcing elements in adjacent layers at an angle, in particular substantially at right angles, takes place. This achieves an efficient and flexible setup of a complex reinforcement. For example, this is done

Providing the at least one reinforcement element by stacking a plurality of the reinforcement elements together.

In a further embodiment of the inventive method for producing the prestressed concrete component, this additionally comprises the step of introducing a separating element, in particular a foam, before the

Concreting the concrete component. This will be a

achieved effective subdivision of the concrete component.

In particular, a foam provides a very flexible, well-applicable and cost-effective subdivision. As a further function, the foam provides an aid to

Positioning of the fibers and / or a fixation of the

 Fibers during concreting. As a separating element, a solid material can be used, for example

Rubber or styrofoam. In a further embodiment of the foregoing

Method for producing the prestressed concrete component, this additionally comprises the step of separating the concrete component after concreting, in particular by

Breaking and / or sawing. Since the foam no

makes a significant contribution to the strength, the individual subdivisions of the concrete component are held together practically only by the fibers. Thus, the

Concrete components easily, in particular by simply breaking, be separated. This will be comfortable and very comfortable

efficiently achieved a division into manageable parts. For example, these parts can be from a

Production plant for concrete components to be distributed to other workplaces and brought there in the final form.

It is expressly stated that each

Combination of the aforementioned examples and

Embodiments or combinations of combinations may be the subject of a further combination. Only those combinations are excluded that would lead to a contradiction.

Further embodiments of the present invention are explained below with reference to figures. Show it:

 Fig. 1 is a simplified schematic representation of a

 Embodiment of the inventive

Armierungselements 10 with carbon fibers 12, which can be stretched by means of two carriers 14; FIG. 2 is a simplified schematic detail view of a carrier 14 according to FIG. 1; FIG.

 Fig. 3 is a simplified schematic representation of a

 Zwischenzustands in the production of a prestressed concrete slab 20 by means of a

Variety of reinforcing elements 10 according to FIG. 1;

4 is a simplified schematic side view of

 Carrier 14 according to FIG. 2;

 Fig. 5 is a simplified schematic representation according to

 Fig. 3, but in addition with a construction foam 40 for dividing the concrete slab 20 and fixing the carbon fibers 12; and

 6 is a simplified schematic side view of

 Carrier 14 according to FIG. 2, but this has a curvature.

The following statements are examples and are not intended to limit the invention in any way.

Fig. 1 shows a simplified schematic representation of an embodiment of the inventive

Reinforcing element 10 in the extended state. Such a reinforcing element 10 serves to produce prestressed concrete components.

The reinforcing element 10 comprises ten individual fibers, in this example as carbon fibers 12 (only partially and two holding elements in the form of two carriers 14. The carriers 14 are spaced apart from one another and connected to one another by the ten carbon fibers 12. The carbon fibers 12 can be tensioned by pulling the carriers 14 apart in their longitudinal direction T.

According to the invention, the carbon fibers 12 are fixed in the carriers 14 in such a way that the stretched carbon fibers 12 open in a straight line into the carriers 14. Furthermore, the form

 Carbon fibers 12 a substantially planar position in which the carbon fibers 12 are arranged substantially parallel and substantially uniformly spaced from one another.

As a result, the Armierungselernent 10 has the shape of a harp. In this example, the reinforcement spacing, i. the distance between the parallel carbon fibers 12, about 10 mm and thus the width of the

Arming element 10 about 10 cm.

Each of the carbon fibers 12 each comprises a carbon roving, that is, a bundle of several thousand

elongated, juxtaposed and substantially equally oriented filaments (about 2 ^λ 000 to about 16 000 filaments). These filaments and thus also the carbon fibers 12 are impregnated with an alkali-resistant resin in the form of vinyl ester resin, so that the carbon fibers 12 form a compact unit, similar to a metal wire. The impregnation can, for example, by means of a Dipping bath through which the roving is pulled to produce the carbon fibers 12.

In addition, the carbon fibers 12 are coated with sand, so that an improved connection of fibers and concrete is achieved. In this example, at a

Insertion length of 100 mm over the mechanical

Thrust connection the full sizing pull force

be transmitted.

Furthermore, the carriers 14 each have two openings 16 (shown by dashed lines) by means of which the carrier 14 on a clamping device (not shown) can be positioned. With the tensioning device, the carbon fibers 12 can be precisely aligned during production of the concrete components, in particular without tensioning horizontal and / or vertical tilting. In another example, the carrier 14 has a hole or a plurality of holes, in particular more than two holes

Positioning of the carrier 14.

In one example, inexpensive materials are used to manufacture the carrier 14. An exemplary material composition and the corresponding manufacture of the carrier 14 will be described with reference to FIG. 2. Other materials may be used since the carrier 14 is not a part of the concrete component to be manufactured is and usually separated after concreting and removed.

FIG. 2 shows a simplified schematic detail view of a carrier 14 according to FIG. 1.

The carrier 14, also referred to as patch, comprises a fiber-reinforced polymer matrix in the form of a polyester matrix with fibers enclosed therein in the form of two glass fiber mats. This polyester matrix encloses the stretched carbon fibers 12 in their end regions.

For example, the size of this polyester matrix is about 10 cm × 10 cm and the total thickness is about 2 mm. In another example, the length extension is the

Polyester matrix in the direction of the carbon fibers 12 between about 10 cm and about 20 cm. The fiber mats form a bottom and top layer with the stretched carbon fibers 12 interposed between these layers and secured therein by lapping with polyester therein. The polyester matrix therefore forms a straight line for the carbon fibers 12

 Guide element (indicated by dashed lines), wherein the carbon fibers 12 within the polyester matrix, i. within the carrier 14, largely

continue straight. By means of the carrier 14, the carbon fibers 12 are fixed in their mutual arrangement, namely in a flat position, substantially parallel and uniformly spaced from one another. The ends of the carbon fibers 12 protrude at the exit side of the carrier 14 a little way beyond the carrier 14. However, the fibers 12 may also terminate in the carrier 14 or flush on its surface, for example when the carrier 14 has been separated from a larger unit.

For example, such a carrier 14 is produced by the following steps:

 - Providing a plurality of adjacent and spaced apart carbon rovings by largely simultaneous withdrawal of the carbon rovings from a corresponding number of supply rolls;

 Impregnating the carbon rovings by passing the carbon rovings through a vinyl ester resin dipping bath so that the carbon rovings form compact carbon fibers 12;

 - Joint extraction of the carbon fibers 12,

 optionally by means of a previously mounted carrier 14, so that the carbon fibers 12 are stretched;

- Applying two fiberglass mats impregnated with polyester to the tensioned carbon fibers 12, one from below and the other from above;

 - Joining the two glass fiber mats, optionally with the addition of an additional amount of the polyester, so that the impregnated glass fiber mats and the polyester enclose the strained carbon fibers 12; and

Allowing the polyester to harden so that the carbon fibers 12 are frictionally secured in the carrier 14. By this lamination, the carrier 14 together with the carbon fibers 12 forms a compact and robust unit.

Fig. 3 shows a simplified schematic representation of an intermediate state in the manufacture of a

prestressed concrete slab 20, for example in a precast concrete slab factory. In this case, the intermediate state corresponds to an arrangement after completion of the

Preparatory work, but before concreting the concrete slab 20.

The arrangement comprises a concreting table (not

shown), a hollow frame 30 disposed thereon and a plurality of identical, inventive

Armierungselementen 10 (partially only schematically

indicated). The hollow frame 30 forms, together with the surface of the concreting table, a casting mold for the concrete, also called a fitted bed.

The reinforcing elements 10 each have a multiplicity of carbon fibers 12 (for the sake of clarity, in some cases only the outer fibers are shown) and two carriers 14 and largely correspond in their construction to that of FIG

Armierungselementen 10 according to FIG. 1. In this example, however, the length of the carbon fibers 12 is about 20 m and the width of the carrier 14 about 1 m. The reinforcement spacing corresponds to the preceding example, ie as in FIG. 1 about 10 mm, so that on the carriers 14 each about 100

Carbon fibers 12 are attached.

When arranging the reinforcing elements 10, the carriers 14 are each pulled apart, so that the carbon fibers 12 are in the hollow frame 30 in the extended state. The carbon fibers 12 are guided through the hollow frame 30 to the outside, so that the ends of the carbon fibers 12 and the carrier 14 are outside the hollow frame 30, for example, with 30 cm distance from the hollow frame 30. In a two-part hollow frame 30 can the

Passage channels are formed by corresponding spaces between the lower part and upper part of the hollow frame 30. In this case, the hollow frame 30 of several

built up superimposed strips, so that the

 Carbon fibers 12 can be guided through the spaces between the individual strips. The gaps may additionally be sealed with sponge rubber and / or brush hairs. In one example, the height is the

superimposed bars 3 mm, 12 mm and 3 mm.

In the illustrated arrangement, the first half of the reinforcing elements 10 is in a first position, parallel and adjacent to each other and the second half of

Armierungselemente 10 in a second layer, also parallel and adjacent to each other, but at right angles to the reinforcing elements 10 of the first layer. The

Reinforcing elements 10 are thus stacked in separate layers and in the two adjacent Layers aligned at right angles to each other. The reinforcing elements 10 therefore form both a

Longitudinal reinforcement as well as a transverse reinforcement, but without individual entanglement of the individual carbon fibers 12.

After arranging the reinforcing elements 10, the carriers 14 are pulled apart, for example with a

Clamping device, also called pretensioning system, or manually with a torque wrench (not shown).

For example, a voltage of at least about 30 kN / m or at least about 300 kN / m is generated, depending on the load requirements of the concrete slab

 (Sizing force).

Subsequent to the illustrated situation, concrete can be poured into the hollow frame 30 prepared in this way in order to concretize the concrete slab 20 in one operation. The parts of the stretched carbon fibers 12, which are located in the hollow frame 30 are enclosed by concrete and thus cast in concrete. Particularly suitable is SCC

Fine concrete (at least C30 / 37 according to standard SIA SN505 262), which penetrates easily through the spaces between the carbon fibers 12

durchfHessen can. The concrete can also be introduced by spraying or spatula in the hollow frame 30 and distributed evenly by vibration.

After the concrete has hardened, the concrete slab 20 can be removed from the hollow frame 30. Here are the Concrete carbon fiber 12 the static reinforcement of the concrete slab 20. The projecting from the concrete parts of

Carbon fibers 12 are broken off at the edges of the concrete slab 20 and removed together with the carriers 14. In this example, the concrete slab produced is about 6 mx 2.5 m and the reinforcement content of this concrete slab 20 is more than 20 mm ² / m width. In another example, the concrete slab produced is about 7 mx about 2.3 m in size.

4 shows a simplified schematic side view of a carrier 14 according to FIG. 2. The carbon fibers 12 open into the carrier 14 in a straight line. Furthermore, the carbon fibers 12 continue in a straight line inside the carrier 14, so that the carrier 14 forms a straight-line guide for the carbon fibers 12. In this example, the length extension of the carrier 14 in the direction of the carbon fibers 12 is about 3 cm.

The carrier 14 may additionally have a profiling 16

have (dashed lines). This example is on a first (top) surface and on top of that

opposite (lower) surface of the carrier 14 a serrated profiling 16 is arranged. These surfaces are for securing the carrier 14 in one

Clamping device (not shown) provided,

for example, by clamping. By the serrated profiling 16, a frictional connection between the carrier 14 and the clamping device in the form of a toothing is achieved. Fig. 5 shows a representation according to FIG. 3, in the

Reinforcing elements 10, but in addition one

Subdivision made by a foam box 40 (as

Shaft line shown) is foamed as a separating element both on the bottom of the mold and under and over the carbon fibers 12. Through this subdivision, no or only a negligible amount of

filled concrete penetrate into that space which is filled in by the subdivision. Thus, only the subspaces of the hollow frame with the therein

Fiber parts concreted. In addition, the construction foam 40 provides a fixation of the fibers during concreting.

After hardening of the concrete, the concrete slab 20 can be broken along the foam compartment divisions into individual slabs. These raw plates can then be further processed, for example, by the raw plates are brought with a circular saw in the desired shape.

In this example, the concrete slab produced is about 20 mx about 20 m in size and the thickness is about 20 mm. By separating the concrete slab 20 according to the subdivision with the construction foam 40, there are 24 smaller slabs with a size of about 5 mx approx. 3 m. From these smaller plates can then be sawed, for example, each 3 table tennis. FIG. 6 shows a simplified schematic side view of a carrier 14 according to FIG. 2, but this has a means for distributing force in the form of a curvature 18. The carbon fibers 12 open straight into the carrier 14 and then run in the interior of the carrier 14, the curvature 18 of the carrier 14 accordingly, also with a curvature. The carbon fibers are 12 in

Entry region of the support 14 is fixed such that the carbon fibers 12 over a distance d of 10 mm

Continue largely straight into the carrier 14. By this form, both a good introduction of the fibers into the carrier 14 and a uniform distribution of the forces to be absorbed is achieved.

Claims

claims A reinforcing element (10) for producing prestressed concrete components, comprising a multiplicity of fibers (12) and a plurality of retaining elements (14) which are interconnected by the fibers (12), such that the fibers (12) are held in place by the retaining elements (14)  Longitudinal direction (T) can be stretched,  wherein the fibers (12) are secured to the support members (14) such that the fibers (12) in the  strained state largely rectilinear in the  Retaining elements (14) open. 2. Armierungselernent (10) according to claim 1, wherein the  Fibers (12) are individual fibers and / or one or more rovings, in particular carbon rovings,  include. Reinforcing element (10) according to claim 1 or 2, wherein the holding elements (14) have guide elements for the fibers (12), in particular a clamping device and / or a carrier for laminating the fibers (12) in the end region, in particular a fiber reinforcement  Polymer matrix, more particularly a polyester matrix. 4. reinforcing element (10) according to any one of the preceding claims, wherein the fibers (12) in the holding elements (14) form a substantially planar position, and in particular are arranged largely parallel and / or substantially uniformly spaced from one another. 5. reinforcing element (10) according to any one of the preceding claims, wherein the Armierungsabstand is about 5 mm to about 40 mm, in particular about 8 mm to about 25 mm, and / or in the holding elements (14) in each case at least 10, in particular at least 40, fibers (12) are attached. Reinforcing element (10) according to one of the preceding claims, wherein the fibers (12) are attached to the  Holding elements (14) are fixed, that the fibers (12) in the tensioned state largely  continue in a straight line in the holding elements (14), in particular over a distance (d) of at least about 5 mm, more preferably at least about 10 mm. Reinforcing element (10) according to one of the preceding claims, wherein the retaining elements (14) include a,  in particular transversely to the direction of the fibers (12)  extending, have means for distributing power, in particular a curvature (18) and / or a  Profiling (16). 8. reinforcement element (10) according to one of the preceding claims, wherein its width is greater than 0.4 m, in particular greater than 0.8 m, and / or whose length is greater than 4 m, in particular greater than 12 m. Method for producing a reinforcing element for prestressed concrete components (20), comprising Steps :  - Providing tensioned fibers (12)  common taking off of a variety of  spaced-apart fibers (12); and  - Attaching a holding element (14) to the  tensioned fibers (12), in particular by clamping and / or laminating, in order to fix the fibers (12) in their mutual arrangement, in particular with respect to distance and / or orientation. A method according to claim 9, wherein the securing of the retaining element (14) takes place during the common extraction of the fibers (12), in particular by moving the retaining element (14) in synchronism with the movement of the fibers (12). Concrete component (20), in particular concrete slab, manufactured using at least one Armierungselements (10) according to one of claims 1 to 8, wherein the bias of the concrete component (20) at least 80%, in particular at least 90%, of Breaking tension of the fibers (12) is. 12. Method for producing a prestressed  Concrete member (20) comprising the steps of:  - Providing at least one reinforcing element (10) according to one of claims 1 to 8;  - Tensioning the fibers (12) of the reinforcing element (10) by pulling the associated  Retaining elements (14); and  - concreting the concrete component (20) with at least partial concreting in of the tensioned fibers (12). 13. The method of claim 12, wherein providing the at least one reinforcing element by arranging a plurality of the reinforcing elements (10) takes place in one layer, in particular by substantially parallel and / or adjacent juxtaposition. 14. The method of claim 12 or 13, wherein the  Providing the at least one reinforcing element (10) by arranging the reinforcing elements (10) in at least two layers, wherein the alignment of the reinforcing elements (10) in adjacent layers takes place at an angle, in particular substantially at right angles. 15. The method of claim 12, further comprising the step of: introducing a separating element, in particular a foam (40), before concreting the concrete component (20).