EP3610092B1 - Reinforcing rod for insertion in a concrete matrix and production method therefor, a reinforcement system made from a plurality of reinforcing rods, and a concrete component - Google Patents

Description

The present invention relates to a reinforcing bar for insertion into a concrete matrix. The reinforcing bar comprises at least one family of filaments running in its longitudinal extent and made of a large number of filaments, which are embedded at least in sections, preferably completely, in a plastic matrix.

Furthermore, the present invention relates to a reinforcement system, a concrete component with a plurality of reinforcement rods and/or at least one such reinforcement system, and a method for producing a reinforcement rod from at least one group of filaments embedded in a plastic matrix.

Reinforcing bars have been used to reinforce concrete structures for a long time. Since concrete can withstand compressive loads quite well, but due to its brittleness, among other things, has poor tensile strength, the reinforcing bars are integrated into the concrete component to absorb tensile forces. The concrete component thus has the advantages of concrete and reinforcing bars. The concrete can absorb compressive forces well, whereas the reinforcing bars can absorb tensile forces well.

Steel reinforcement bars have been known for a long time to reinforce concrete components. Although their use has proven itself in millions of numbers, they are very heavy due to the steel. In addition, steel rusts over time, which affects the longevity of the corresponding concrete component. The consequences are high maintenance costs or demolition and new construction work.

Reinforcement rods for reinforcing concrete components made of homogeneous strand-shaped filaments made of carbon, for example, which are embedded in a plastic matrix, have also been discussed and some have already been used in buildings. However, their anchoring in the concrete matrix of a concrete component is insufficient, which is why such reinforcing rods have not yet become established.

DE 10 2014 102 861 A1 shows a reinforcing bar according to the preamble of claim 1. The object of the present invention is to provide a relatively light reinforcing bar with which an improvement in its anchoring in a concrete component can be realized.

The object is achieved by a reinforcing bar for introduction into a concrete matrix according to claim 1 and a corresponding production method according to claim 15, also by a reinforcement system made of several reinforcing bars according to claim 13 and a concrete component according to claim 14 with reinforcing bars and / or a reinforcement system with the features of independent patent claims.

A reinforcing bar for insertion into a concrete matrix to reinforce a concrete member is proposed. The reinforcing bar can absorb tensile forces particularly well and transfer them to a foundation of the concrete component. The reinforcing bar comprises at least one group of filaments running in its longitudinal extent and made of a large number of filaments, which are embedded at least in sections in a plastic matrix. The plastic matrix is particularly preferably a duroplastic or a thermoplastic plastic matrix. In the case of a duroplastic, epoxy resin is a good example. Furthermore, the filaments can also be completely embedded in the plastic matrix and connected to one another. The group of filaments connected by the plastic matrix has the advantage over a steel reinforcement bar, for example, that the weight of the reinforcement bar is reduced.

In order to improve anchoring of the reinforcing bar in the concrete component, the reinforcing bar has elevations spaced apart from one another in the longitudinal extent of the reinforcing bar and indentations spaced apart from one another in the longitudinal extent of the reinforcing bar.

Furthermore, the reinforcing bar can have a plurality of elevations spaced apart from one another along a line running in the aforementioned longitudinal extension on the bar surface. Indentations can be arranged between the elevations, so that the elevations and indentations alternate along this imaginary line. In this case, for example, the elevations rise in a radial or transverse direction of the reinforcing bar (in relation to its cross section) beyond the indentations.

If the reinforcing bar is arranged in the concrete component and is therefore preferably completely surrounded by the concrete matrix, the concrete matrix is adapted to the contour of the elevations and the indentations, with the concrete matrix in particular also filling out the indentations. The concrete matrix forms, so to speak, a negative form of elevations and indentations around the reinforcing bar. As a result, after the concrete matrix has hardened, the elevations and indentations of the reinforcing bar interlock with the surrounding concrete matrix, so that a tensile force in the longitudinal extension of the reinforcing bar can be exchanged between the concrete matrix and the reinforcing bar. In particular, the tensile force is transferred from the concrete matrix to the rebar, which is better able to dissipate it. The result is a self-locking of the reinforcement bar in the concrete matrix, so that tensile forces in the direction of the reinforcement bar can be excellently absorbed.

According to the invention, at least two indentations that are spaced apart in said longitudinal extent of the reinforcing bar and preferably follow one another have a different alignment in the circumferential direction of the reinforcing bar. These indentations thus have a different orientation, with spaced-apart indentations being formed, for example, linearly, which are rotated about the center line in the circumferential direction of the reinforcing bar and are thus aligned in different directions. Due to the different orientations, sequences of indentations are formed, which are formed differently in different directions (seen in each case in the circumferential direction of the reinforcing bar) and can therefore be optimally matched to their self-locking use in a concrete matrix.

Among other things, the range of possibilities in lightweight concrete construction is considerably expanded by means of the invention. In particular, the invention makes it possible to realize very flat concrete parts that can nevertheless withstand tensile loads. This is of immense advantage, especially against the background of the emerging global scarcity of the raw material sand. The invention makes it possible to carry out an optimized dimensioning of the concrete part reinforced by means of the reinforcing bars according to the invention and to adapt the anchoring of the reinforcing bars in the concrete part to the desired load.

According to the invention, said indentations and elevations are realized by pinching. Each pinch reduces the width of the rebar (when viewed from above) in at least one direction, thereby forming the indentations. Because the filaments of the rebar are essentially incompressible, the filaments deflect relative to each other when pinched. As a result, not only the indentations are formed by the pinching, but also the elevations. This is also advantageous with regard to a manufacturing method of the reinforcing bar. With the help of the indentations, the indentations and the elevations can be formed at the same time.

As described, the filaments can deviate from their originally mutually parallel position when being squeezed. Crushing can particularly and preferably cause filaments to deflect laterally, i.e. in the radial direction of the rebar. This effect is further enhanced if there is a counter-element on the side opposite the pinch. If they are squeezed, the filaments deviate to both sides and opposite lateral elevations form. The indentations and the elevations can thus in particular be arranged perpendicularly to one another. A reinforcing bar with a sequence of tetrahedral sections aligned in pairs with one another is preferably obtained in this way.

When squeezed from only one side, the filaments can—if no corresponding counter-element is provided—evade to the opposite side of the rod surface, so that the filaments bulge there and as a result an elevation is formed. The indentation and the elevation are thus arranged radially opposite one another on the reinforcing bar.

The indentations and elevations can thus be formed in the rebar without weakening its tensile strength. As a result of the pinching, if an opposing counter-element is present, the filaments only deviate laterally, ie in the radial direction of the reinforcing bar, and remain intact without breaking in particular. Preferably, at least two indentations that are spaced apart in said longitudinal extent, preferably one after the other, have a different orientation in the circumferential direction of the reinforcing bar. Due to the different orientations, sequences of indentations are formed, which are formed differently in different directions (each viewed in the circumferential direction of the reinforcing bar) and can therefore be optimally matched to their use in a concrete matrix.

It is particularly preferred that said different alignment of two indentations that are spaced apart in the longitudinal extent of the reinforcing bar, in particular directly following one another, is realized in that these indentations have an angular offset of greater than 0° and less than 180° to one another in the circumferential direction of the reinforcing bar. In other words, at least these two indentations are arranged rotated relative to one another in the circumferential direction, ie aligned differently. The indentations can be offset in the longitudinal extent of the reinforcing bar and twisted or rotated in relation to one another. In this way it can be achieved that the reinforcing bar hooks into the concrete matrix in several radial directions of the reinforcing bar and is thus better anchored in it.

It is advantageous if a further indentation is arranged radially opposite one another in at least some of the indentations in the reinforcing bar. Preferably, all the indentations have a further indentation on the radially opposite side of the rebar, these indentations being obtained by pinching the rebar from the two said sides. Likewise, it is preferred that such pairs of indentations are formed symmetrically to the center line of the reinforcing bar, ie the indentations are in particular of the same depth. The reinforcing bar thus particularly preferably has a sequence of two opposing indentations. Due to the two indentations, the lateral deflection of the filaments also causes the elevations, which are offset by 90° to this (in the circumferential direction of the reinforcing bar). In the circumferential direction of the rebar, the cyclic order is then: indentation-elevation-indentation-elevation. The elevations and indentations are preferably distributed evenly around the circumference of the reinforcing bar. An elevation and an indentation are then each offset by 90° in the circumferential direction of the reinforcing bar.

This can improve the anchoring of the rebar in the surrounding concrete matrix.

However, according to an alternative, only a single elevation can be arranged between the two indentations if, for example, the squeezing shape prevents the filaments from being able to escape to both, in particular vertical, sides between the indentations.

It is particularly advantageous if the indentations extend over the entire width of the reinforcing bar. In this way large volumes of concrete penetration can be obtained to optimize the self-locking of the rebar.

Indentations that follow one another in the longitudinal extent of the reinforcing bar are particularly preferably arranged separately or separately from one another or run independently of one another without merging into one another. In particular, it is preferred if the indentations do not run helically around the reinforcing bar, but are provided independently of one another and at a distance in said longitudinal extent in the reinforcing bar.

The indentations are particularly preferably designed to run linearly. The indentations can be formed in the reinforcing bar, for example, by means of a cylindrical pinching edge of a pinching tool. In general, the shape of the indentations can be designed with the help of the shape or design of the pinch edge. In particular, a linear or straight indentation or pinch can be formed by means of a straight pinch edge. As a result, the linear indentation has a straight indentation line.

Alternatively, the squeezing edge of the squeezing tool can also be bent, curved and/or arched, so that a bent, curved and/or arched indentation is formed.

Additionally or alternatively, the indentations can have a diameter that is smaller than the width of the at least one group of filaments. Such indentations can preferably be squeezed into the reinforcing bar by means of a stamp-like squeezing tool. In addition or as an alternative, the squeezing tool can also have a number of stamps, so that a number of indentations arranged next to one another in the circumferential direction can be formed. The squeezing tool can then be designed in the form of a comb, for example.

Furthermore, it is advantageous if the angular offset between indentations, preferably in the form of indentations running linearly, is between 10° and 170°, in particular between 45° and 135°, preferably 90°, in the circumferential direction. The anchoring of the rebar can be improved by the angular offset, since the concrete matrix interlocks with the rebar from several radial directions.

Furthermore, it is advantageous if the angular offset of several or all successive indentations changes to the same extent, for example by 90° in each case. However, it is easily possible for the angle or angular offset of successive indentations to change, for example, by 60° in each case or by other angular dimensions, which may also not be constant.

It can also be advantageous if a pattern of consecutive indentations is repeated periodically along said longitudinal extension. A pattern can include a sequence of indentations arranged one behind the other, each of which has an angular offset (greater than 0°, less than 180°) relative to one another in the circumferential direction. For example the second indentation in the sequence can be angularly offset by 90° in the circumferential direction relative to the first indentation. This pattern is then repeated periodically along the rebar.

However, the angles between the indentations of a pattern are not necessarily the same.

It is advantageous if the indentation lines of the indentations have an angle of inclination of between 10° and 90° to the longitudinal extent of the reinforcing bar, ie run obliquely to the longitudinal extent of the reinforcing bar. If the indentation is a linear indentation, it will have an indentation line, which may correspond to the line where the rebar is pinched deepest to form the indentation. Due to said angle of inclination, the indentations are arranged obliquely to the longitudinal extent of the reinforcing bar, so that the indentations increase in volume and the hooking of the reinforcing bar in the concrete matrix is improved.

The angle of inclination of some, preferably all, indentation lines with the longitudinal extent is particularly advantageously 90°, i.e. the indentation line is oriented perpendicularly or transversely to the longitudinal extent. However, not all indentation lines need to have the same angle of inclination.

Furthermore, the indentations are preferably arranged at a distance of between 1 mm and 50 mm from one another in the longitudinal extension. The indentations can also have a distance of between 5 mm and 30 mm in the longitudinal direction. The distance between two indentations is preferably between 10 and 20 mm, for example 15 mm.

An advantageous development of the invention is when the at least one set of filaments made of carbon fiber rovings (carbon rovings), glass fiber rovings and/or other high-performance rovings, such as Ceramic fiber rovings, quartz fiber rovings, basalt fiber rovings, boron fiber rovings, aramid fiber rovings and/or dyneema fiber rovings. The rovings are already pre-impregnated filament bundles with a plastic matrix known from the prior art, so that a manufacturing process for the reinforcing bar is simplified as a result. The carbon fibers and/or the glass fibers also have a good tensile strength/weight ratio. For example, the carbon fibers have a density in the range of about 1.8 g/cm ³ , the tensile strength of the filament bundle formed from them being quite comparable to that of steel (density about 7.5 g/cm ³ depending on the type of steel). With the help of the materials described here, the weight of the reinforcing bar can be significantly reduced while the tensile strength remains the same.

The at least one set of filaments can also comprise at least 12,000, 24,000 or at least 48,000 individual filaments. A higher number of filaments increases the tensile strength of the filament sheets and thus of the rebar.

An advantageous further development of the invention consists in the reinforcing bar having a plurality of indentations and elevations which are regularly spaced apart from one another in the longitudinal extent of the reinforcing bar. Alternatively, the indentations and elevations can also be arranged at an irregular distance from one another. In both cases, the highest points of the elevations can preferably be arranged at a distance of between 1 mm and 100 mm from one another along the line running on the rod surface described above. The distance between the highest points of the elevations can advantageously be between 5 mm and 50 mm. Such a spacing results in an advantageous interlocking between the elevations and indentations of the reinforcing bar and the enclosing concrete matrix. The distance between the elevations allows the concrete matrix to flow into the area of the indentations. For example, the distance can also be selected such that this corresponds to an average diameter of gravel grains arranged in the concrete matrix. As a result, the gravel grains can get caught between the elevations, so that the transmission of force from the concrete matrix to the reinforcing bar by means of the gravel grains is improved.

It is particularly advantageous if the amount or the size of the cross-sectional area of the reinforcing bar changes along its length, preferably periodically. Regions with a larger cross-sectional area correspond to the peaks, whereas regions with a smaller cross-sectional area correspond to the indentations. In the case of at least one group of filaments embedded in a plastic matrix, matrix material is pressed outwards between the filaments when it is squeezed and thus reaches the surface of the reinforcing bar and is preferably removed there, for example by machine. The resulting cross-sectional area in the area of such an indentation obtained by pinching is then smaller than in non-pinched areas.

A non-uniform density distribution of the filaments in the plastic matrix is associated with cross-sectional areas of different sizes. In the case of a lower density, in particular spatial density, of the filaments, these are spaced farther apart overall, so that they take up a larger volume of space. The space between more loosely arranged filament sections is filled with more plastic matrix to strengthen the rebar and increase the fixation of the filaments.

In the areas of the rebar with higher density, the indentations are formed, which are preferably created by local squeezing of the at least one group of filaments. In contrast to the unpinched areas, there is less plastic matrix between the filaments. In this way, the elevations and the indentations can be formed via the internal structure, ie the distances between the filaments.

It is also advantageous if a reinforcing bar according to the invention is essentially formed from wedges or tetrahedrons that follow one another—directly or at a distance—along the longitudinal extent of the reinforcing bar, which wedges or tetrahedrons are formed in particular by the said squeezing process. The wedges or tetrahedrons are formed by the shape of the reinforcing bar, i.e. its cross section, which preferably changes periodically in the longitudinal direction. The wedges or tetrahedrons are preferably arranged in alternating directions. For example, two successive wedges or tetrahedrons can be oriented opposite to one another, with edges of two adjacent wedges or tetrahedrons meeting one another. These edges are preferably formed by a squeezing process. A subsequent indentation offset in the circumferential direction by an angle, preferably 90°, also preferably by local squeezing of the at least one filament family, produces an edge of the tetrahedron rotated by this angle, which then preferably forms the edge of a further tetrahedron. The wedges or tetrahedrons therefore give the reinforcing bar a defined shape, so that the concrete component properties, in particular the reinforcing bars in the concrete matrix, can be calculated with regard to their statics.

Due to the wedges or tetrahedrons, the filaments fan out periodically and the mass distribution of the plastic matrix fluctuates in the longitudinal direction of the rod.

Said tetrahedrons can in particular be regular tetrahedrons, ie all edges of the tetrahedron are of equal length and/or all triangular faces of the tetrahedron are equal to one another. Additionally or alternatively, the tetrahedrons can also be irregular tetrahedrons, for example if at least one or more edges are longer than others. The tetrahedra can in particular be arranged in such a way that the indentations mentioned above determine two opposing edges of the tetrahedron that are twisted relative to each other. As described above, two adjacent tetrahedra touch at the indentations.

Furthermore, the height of the tetrahedron, measured in the longitudinal direction of the reinforcing bar between two opposing edges of a tetrahedron that are twisted or angularly offset and formed by the indentations, can be, for example, two to five times greater than the length of each of these two edges.

A further advantageous development of the invention is when the reinforcing bar comprises at least a first and a second set of filaments. The first and the second set of filaments preferably run parallel to one another in sections and are connected to one another at least in sections. For example, the second set of filaments is placed on the first set of filaments.

In order to ensure sufficient interlocking of the concrete matrix in the indentations arranged between the elevations, it is advantageous if the width of the reinforcing bar (seen in plan view) in the area of at least some elevations is at least 10% greater than in the area of at least some indentations (measured in the same transverse direction of the rebar). Said width of at least some, preferably all, elevations is preferably at least 20% or at least 30% or even greater than in the area of at least some indentations.

According to the invention, the filaments in a reinforcing bar according to the invention run in alternating directions, at least in sections. The interstices between the filaments can be filled either only by said plastic matrix or by the plastic matrix and an additional solid.

In a further aspect of the invention, a reinforcement system made up of several reinforcement bars according to the invention is proposed.

The reinforcement bars are connected to the reinforcement system by means of coupling elements. The coupling elements help to distribute the tensile force under the reinforcement rods of the reinforcement system, so that a tensile force acting at a point on the concrete component is distributed over a large area.

The reinforcement system can be designed, for example, as a reinforcement mat and/or as a reinforcement composite, with the reinforcement rods preferably being offset relative to one another in their longitudinal and transverse directions. In this way, flat concrete components, such as building ceilings and/or walls, can be reinforced. The planar arrangement of reinforcing rods connected to one another also makes it easier in particular to handle the mats or composites before installation in a concrete part.

Additionally or alternatively, the reinforcing rods and/or the reinforcing assemblies can also be offset in a further transverse direction perpendicular to the transverse direction just mentioned. Here, the reinforcement system is not only flat, but also spatial. For example, the reinforcement system for reinforcing a corner of a building can comprise two reinforcement mats that are perpendicular or at an angle to one another. It is also possible to build 3-dimensional structures from reinforcing bars.

The coupling elements for two crossing reinforcing rods can advantageously include metal and/or plastic wires, sewing threads and/or an adhesive, in particular a hot-melt adhesive. The metal wires can include, for example, aluminum or steel wires and are used when the coupling elements have large tensile forces between the individual to distribute reinforcing bars. Plastic wires can be used when the weight of the reinforcement system is to be kept low.

Hot-melt adhesive is particularly preferably used, which is easy to apply and gives the reinforcement system sufficient support for easy handling before installation in a concrete component.

A concrete component with a plurality of reinforcing bars according to the invention and/or at least one reinforcement system according to the invention is also proposed as part of the invention.

The concrete component comprises a concrete matrix surrounding the rebars and/or the at least one reinforcement system, wherein the rebars and/or the at least one reinforcement system are anchored in a form-fitting manner, forming a self-locking mechanism in the concrete matrix. The anchoring is formed in that the concrete matrix encloses the reinforcement bar and engages in the indentations arranged between the elevations. As a result, the hardened concrete matrix interlocks with the elevations and indentations, so that the reinforcement rods and/or the at least one reinforcement system are anchored in the concrete matrix.

In addition, a non-positive and/or material connection can be formed between the concrete matrix and the reinforcement rods and/or the at least one reinforcement system. As a result, the anchoring of the reinforcement rods and/or the at least one reinforcement system in the concrete matrix is further increased.

The at least one family of filaments of the rebars (and thus the rebars themselves) or at least some of the rebars of the at least one reinforcement system preferably run in the main load direction of the concrete component. As a result, the tensile forces acting on the rebars and/or the at least one reinforcement system can be optimally diverted to the longitudinal extent of the filament array in order to utilize the high tensile strength of the filament array. A further aspect of the invention proposes a method for producing a reinforcing bar according to the invention with at least one group of filaments embedded in a plastic matrix.

In the process, at least one sheet of filaments is first placed in a mold or crimping tool inserted. In addition or as an alternative, the at least one group of filaments can also be guided through a forming or squeezing tool, so that the reinforcing bar can be produced endlessly. The at least one group of filaments is particularly preferably already pre-impregnated with a duroplastic (in particular epoxy resin) or thermoplastic matrix, the group of filaments with the plastic matrix being referred to as a so-called prepreg.

Alternatively, the plastic matrix can also be introduced into the mold separately from the group of filaments. This can be done before or after introducing the filament family into the mold. The plastic matrix can, for example, have a (viscous) liquid consistency, so that the plastic matrix is distributed by itself or by spreading in the mold and/or on the filament bundle.

In a further step, the filaments of the at least one group of filaments present in the plastic matrix are formed in said mold with the application of at least pressure (in the case of a duroplastic plastic matrix) and possibly heat (in particular in the case of a thermoplastic, but possibly also a duroplastic plastic matrix). - Or squeezing tool under formation of in the longitudinal extension of the reinforcing bar spaced apart elevations and in the longitudinal extension of the reinforcing bar spaced indentations solidified. The indentations are formed in such a way that at least two indentations that are spaced apart in said longitudinal extension have a different alignment in the circumferential direction of the reinforcing bar.

Said filaments can also be arranged as alternating elevations and indentations along a line running longitudinally on the rod surface.

In the case of a thermoplastic matrix, the supply of heat causes this matrix to crosslink and solidify, so that the shape and in particular the elevations and indentations of the reinforcing bar are retained. In the case of a duroplastic matrix, crosslinking and curing already take place at room temperature; however, heat can also be introduced to accelerate the curing process.

In an advantageous development of the manufacturing method according to the invention, at least a first and a second filament bundle are brought together in the mold and/or through the mold in such a way that the first and the second filament bundle are arranged parallel to one another at least in sections.

Figur 1

eine Schnittansicht eines Ausschnitts einer allgemeinen Ausführungsform eines Bewehrungsstabs mit Erhebungen und Einbuchtungen;

Figur 2a-2b

ein konkretes erstes Ausführungsbeispiel eines Bewehrungsstabs in zwei zueinander senkrechten Längsschnitten;

Figur 2c-2d

perspektivische Ansichten (nicht transparent, halb-transparent) eines Ausschnitts des Bewehrungsstabs der Figuren 2a-2b;

Figur 2e

eine perspektivische Ansicht eines Ausschnitts eines idealisierten Bewehrungsstabs mit dem grundsätzlich gleichen Aufbau wie in den Figuren 2a-2d;

Figur 2f

eine perspektivische Ansicht eines Ausschnitts einer zweiten Ausführungsform eines Bewehrungsstabs, und

Figur 3

ein Ausführungsbeispiel eines Bewehrungssystems.

Further advantages of the invention are described in the following exemplary embodiments. Show it:

figure 1

a sectional view of a detail of a general embodiment of a reinforcing bar with elevations and indentations;

Figure 2a-2b

a specific first embodiment of a reinforcing bar in two mutually perpendicular longitudinal sections;

Figure 2c-2d

Perspective views (non-transparent, semi-transparent) of a section of the rebar of the Figures 2a-2b ;

Figure 2e

a perspective view of a section of an idealized rebar with basically the same structure as in the Figures 2a-2d ;

Figure 2f

a perspective view of a section of a second embodiment of a reinforcing bar, and

figure 3

an embodiment of a reinforcement system.

figure 1 shows a sectional view of a section of a reinforcing bar 1 for introduction into a concrete matrix in order to reinforce a concrete component. The reinforcing bar 1, which serves to clarify the terminology used here and for general advantageous features of the invention, comprises at least one filament group 2, which is formed from a large number of filaments (not shown here) running largely parallel in the longitudinal extent X a reference number indicated plastic matrix 16 are connected to the reinforcing bar 1. The plastic matrix 16 can be, for example, a duroplastic, a thermoplastic and/or an elastomeric material that holds the filaments together and permanently fixes them for the purpose of forming the reinforcing bar 1 . The number of filaments of the filament sheet 2 can be, for example, in the range of at least 12,000 or even at least 48,000, with a higher number is accompanied by a higher tensile strength of the reinforcing bar 1 .

The at least one family of filaments 2 can advantageously be carbon fiber rovings, glass fiber rovings and/or other high-performance rovings, such as ceramic fiber rovings, quartz fiber rovings, basalt fiber rovings, boron fiber rovings, aramid fiber rovings and/or dyneema fiber rovings, comprise, said rovings comprising the endless fibers or filaments embedded in the plastic matrix. Such fibers or filaments have a high tensile strength with a low weight. For example, the low weight is an advantage over steel rebars, which are significantly heavier (with comparable tensile strength) and prone to rusting.

Due to the orientation of the filament bundles in the longitudinal extent X of the reinforcing bar 1, a tensile force acting on the reinforcing bar 1 in its longitudinal extent X is thus essentially transmitted to the individual filaments. The filaments are therefore essentially responsible for the tensile strength of the reinforcing bar 1.

The reinforcing bar 1 also has a transverse extension Y oriented perpendicularly to the longitudinal extension X. The longitudinal extent X and the transverse extent Y also define a longitudinal direction X and a transverse direction Y of the reinforcing bar 1.

In order to increase the anchoring of the reinforcing bar 1 in the concrete matrix, the reinforcing bar 1 according to the invention has elevations 3 spaced apart from one another in the longitudinal extent X and indentations 4 spaced apart from one another in the longitudinal extent X.

The reinforcing bar 1 can also have several lines along a line L running in the longitudinal extension X of the reinforcing bar 1 on the bar surface have spaced-apart elevations 3 and between the elevations 3 arranged indentations 4. The line L running along the bar surface can follow the elevations 3 and indentations 4 and runs overall in the same direction as the center line M of the reinforcing bar 1.

In particular, when the reinforcing bar 1 is arranged in a concrete component, its concrete matrix completely encloses the reinforcing bar 1 and thus also the elevations 3 and the indentations 4. In particular, the concrete matrix is also arranged in the indentations 4 and thus forms one with the elevations 3 and the indentations 4 positive-locking connection. The hardened concrete matrix interlocks in the indentations 4, so that the reinforcing bar 1 develops a resistance to displacement in relation to the concrete matrix in the direction of the longitudinal extent X. Overall, self-locking of the reinforcing bar 1 according to the invention in the concrete matrix is achieved.

Each two adjacent elevations 3 can have a distance 5 of between 1 mm and 100 mm from one another in the longitudinal extension X. For example, the distance 5 can also be between 5 mm and 50 mm. As a result, grains of gravel arranged in the concrete matrix, for example, can become embedded in the indentations 4, so that these also contribute to the interlocking, i.e. self-locking, of the reinforcing bar 1 in the concrete matrix.

In the according figure 1 shown embodiment, the elevations 3 and the indentations 4 alternate at periodically constant distances 5 from. However, the distance 5 between the elevations 3 does not have to be constant over part or over the entire longitudinal extension X of the reinforcing bar 1 . The reinforcing bar 1 can, for example, also have sections in which the distance 5 between the elevations 3 (or the distance between the indentations 4) is reduced or increased and/or varies, for example.

Furthermore, the elevations 3--seen in plan view of the rebar--have a width 6 and the indentations 4 have a width 7, these widths being measured transversely to the rebar 1 and along a line of the rebar 1. It is advantageous if the width 6 of the elevations 3 is at least 10% greater than the width 7 of the indentations 4, preferably by at least 20%, for example by at least 30%. As a result, excellent interlocking of the reinforcing bar 1 in the surrounding concrete matrix can be achieved. Furthermore, a subset of the elevations 3 can have a different width 6 than the remaining elevations 3 of the reinforcing bar 1.

The elevations 3 and the indentations 4 are preferably based on an uneven density distribution of the filaments in the plastic matrix 16. In the areas of the elevations 3, for example, the filaments of the filament family 2 are arranged more loosely, with the intermediate space formed between them being filled with the plastic matrix 16. On the other hand, in the areas of the indentations 4, the filaments are arranged more densely so that they are closer together and thus take up less space. There is less plastic matrix 16 in areas of indentations 4 than in areas of elevations 3.

the Figures 2a-d show a specific embodiment of the rebar 1 with elevations 3 and indentations 4. The rebar 1 here has a large number of tetrahedra arranged endlessly one behind the other in the longitudinal direction, in which successive tetrahedra each have one longitudinal edge in common and a pattern of two tetrahedra each in the longitudinal extension X of the reinforcing bar 1 is repeated periodically.

The two show more precisely Figures 2a, 2b two longitudinal sections through a corresponding reinforcing bar 1, which are offset by 90° in the circumferential direction from one another, that is to say rotated by 90° about the center line M. If there is an indentation 4 in a transverse direction, there is an elevation 3 in the same longitudinal section of the reinforcing bar 1 in the transverse direction perpendicular thereto. In other words, the contours of the reinforcing bar 1 are identical along two lines running on the bar surface through the elevations 3 and indentations 4 and are offset from one another by 90° in the circumferential direction, but are phase-shifted by 180° in the longitudinal direction of the reinforcing bar 1 (through the two vertical dashed lines indicated).

the Figures 2c, 2d show the same rebar 1 made of tetrahedrons or double wedges lined up next to each other, but in a slightly perspective view. In addition, Figure 2d the course of the rear and lower edges of the tetrahedron, which is actually not visible, is shown in dashed lines for illustration.

Figure 2e shows a perspective view of a detail of a rebar 1, which is an idealized representation of the rebar 1 of Figures 2a-2d is. In the perspective view, the dotted lines are hidden by the reinforcing bar 1. The perspective view according to the Figure 2e and the following Fig. 2f is also to be understood only schematically. Of course, the reinforcing bar 1 has a certain width in the areas of the elevations 3 and indentations 4 shown here, which is given by the diameter of the multiplicity of filaments of the reinforcing bar 1 . Furthermore, of course, there are no sharp angles in the area of the elevations 3 and indentations 4 . Rather, the reinforcing bar 1 has a certain wavy shape (see Fig. Figures 2a-2d ). Furthermore, for the sake of clarity, not all features of this Figure 2e provided with a reference number, but only those features that are useful for further understanding. Furthermore, all are in the coordinate system shown directions X, Y1, Y2 in pairs perpendicular to each other. The same applies to the following perspective views of reinforcing bar 1.

According to the present exemplary embodiment, the indentations 4, 4' and the elevations 3, 3' are formed by means of pinches 19a-19c, which each run perpendicular to the pinch directions E1, E2, E3. For example, areas of the at least one group of filaments 2 that are still unpinched are pinched during the production process by applying a compressive force in the pinching direction E1, E2 or E3. The pinched areas 19a-19c reduce the local diameter in the respective pinching direction E1, E2, E3 in these areas, so that the indentations 4, 4' are formed at these points. The crushed areas 19a-19c along the respective crushing direction E1, E2, E3 have another effect. Since the filaments and the plastic matrix 16 are essentially incompressible, the filaments have yielded laterally at the pinched areas 19a, 19b and 19c in relation to the respective pinching directions E1, E2 and E3. As a result, in the present exemplary embodiment, the elevations 3, 3' are formed perpendicular to the indentations 4, 4'.

According to the present embodiment of the Figure 2e the crushing in the first crushing direction E1 causes a first crushing 19a, which forms the indentation 4 and which in the present case is aligned along the second transverse direction Y2 or in the transverse direction Y2 of the reinforcing bar 1. On the side radially opposite to the first indentation 19a, another second indentation 19b is provided by the application of force in the direction of pinching E2, which forms the indentation 4' and which is also aligned along the second transverse direction Y2 or in the transverse direction Y2 of the reinforcing bar 1. As a result, the indentations 4, 4' or the pinched areas 19a, 19b are arranged on radially opposite sides of the reinforcing bar 1 and run parallel to one another and together in the transverse direction Y2. It is advantageous if the indentations 4, 4' or the constrictions 19a, 19b are pressed symmetrically and thus also equally deep into the filament sheet 2, so that their distance from the center line M is the same.

By pinching in the pinching direction E3, which runs perpendicular to the two pinching directions E1 and E2, an indentation 4 or indentation 19c is obtained, which is aligned along the first transverse direction Y1 or in the transverse direction Y1 of the reinforcing bar 1. The same also applies to the indentation or pinch radially opposite this indentation 4, which is also aligned in the transverse direction Y1.

Consequently, the indentations 4 that follow one another in the longitudinal extent X have a different alignment in the circumferential direction of the reinforcing bar 1, in the present case an alignment that is offset by 90° relative to one another.

In the present case, the constrictions 19a, 19b also form two elevations 3, 3′, which are caused by the lateral deflection of the squeezed filaments. The elevations 3, 3' are spaced apart in the second transverse direction Y2 and are oriented or aligned perpendicular to the two indentations 4, 4'. The elevations 3, 3' and the indentations 4, 4' thus form a cross shape when viewed in the longitudinal extension X, the elevations 3, 3' being arranged along one arm of the cross and the indentations 4, 4' along the associated cross arm.

The pinched areas 19a-19c can be introduced into the reinforcing bar 1, for example, with the aid of pinching edges of a pinching tool. The respective squeezing edge can, for example, be straight, so that when the compressive force is applied in the squeezing direction E1, E2 or E3, they form the pinched areas 19a-19c. By means of the pinch edges can, for example, according to the present embodiment Figure 2e Indentation lines or pinch lines L1, L2 are formed. here the two elevations 3, 3' are arranged at the two ends of the first indentation line L1. The first indentation line L1 is arranged between the two indentations 4, 4'.

Additionally or alternatively, the pinch edges can also be arched, bent and/or wavy, so that correspondingly arched, bent and/or wavy indentation lines or pinch lines L1, L2 can be formed. Additionally or alternatively, at least some of the pinched areas 19a-19c can also be realized by means of a squeezing tool that has a stamp with a diameter that is smaller than the width of the at least one filament bundle (as viewed from above). It is also possible for several such stamps to form the aforesaid squeezing tool.

In a further area of the reinforcing bar 1, a third indentation 4 designed as a pinch 19c is also formed by applying a compressive force in the pinching direction E3, which in addition to the indentation 4 creates two lateral elevations 3. On the rear side of the reinforcing bar 1 in the perspective view, an indentation designed as a pinch is also arranged, which is arranged on the radially opposite side of the third pinch 19c. For the sake of clarity, this pinch and the associated indentation are not provided with a reference number.

In the present case, the indentation lines L1, L2 each run perpendicularly (90°) to the longitudinal extent X of the reinforcing bar and parallel to the first or second transverse direction Y1, Y2. Alternatively, the angle of the indentation lines L1, L2 to the longitudinal extent X can be between 10° and 90°, so that the indentation lines L1, L2 run obliquely to the said longitudinal extent X (not shown).

Preferably, at least some of the indentations 4, 4′ and in this case also the pinched areas 19a-19c form a periodically repeating pattern. In the present case, the first and the second indentation 19a, 19b or the associated indentations 4, 4' with respect to the third indentation 19c or the associated indentation 4 (as well as the concealed indentation on the side radially opposite the third indentation 19c) rotated by 90 ° in the circumferential direction of the reinforcing bar 1. This pattern of four indentations or indentations of two adjacent tetrahedrons T is repeated periodically in the longitudinal extension of the reinforcing bar 1 .

In alternative exemplary embodiments that are not shown here, two indentations 4 that are spaced apart in the longitudinal extent X can have an angular offset in the circumferential direction of between 10° and 170° and not equal to 90°. For example, an indentation 4 is only slightly twisted or offset by an angle of 30° relative to another indentation 4 that is spaced apart in the longitudinal extent X.

According to the present embodiment of the Figure 2e the reinforcing bar 1 has a sequence of tetrahedrons T arranged one behind the other. Only a tetrahedron T of the reinforcing bar 1 is provided with a reference number. The pattern-like, repeating tetrahedron shape is given by the alignment of indentations 4 following one another in the longitudinal extent X of the reinforcing bar 1 with an angular offset of 90° in the circumferential direction. Since the successive indentations 4 are linear, they form the opposite edges of a tetrahedron T. The in Figure 2e The section of the reinforcing bar 1 shown has six tetrahedrons T, which are identical to one another. In this case, three tetrahedra T have an opposite orientation to the other three tetrahedra T, the tetrahedra T having opposite orientations in the longitudinal extension X in an alternating sequence.

The tetrahedron T of the present embodiment according to the Figure 2e are regular tetrahedrons T, where all four faces of each tetrahedron T are equilateral triangles and all six edges of the tetrahedron T are of equal length.

Furthermore, two consecutive indentations 4 have a distance A in the longitudinal extent X from one another. This distance A can be between 1 mm and 50 mm. However, the distance can also be between 5 mm and 30 mm or between 10 mm and 20 mm. The distance between two indentations is preferably 4 15 mm. The distance A corresponds to the height of the tetrahedron T.

Figure 2f shows a perspective view of a section of a further exemplary embodiment of the reinforcing bar 1. The same or similar features to those above in particular Figure 2e are not explained again for the sake of simplicity. The reinforcing bar 1 in turn has a series of a large number of tetrahedrons T, which are oriented alternately in opposite directions. In the present case, the two indentation lines L1 and L2 have the same length. Furthermore, the four edges of each tetrahedron T connecting the two indentation lines L1 and L2 are longer than the two indentation lines L1 and L2. These four edges have the same length as each other. The tetrahedra T are consequently irregular tetrahedra.

In an alternative exemplary embodiment, not shown here, the four edges that connect the two indentation lines L1, L2 to one another can have different lengths.

According to the Figures 2a-2f the indentations 4 which follow one another in said longitudinal extent X are arranged separately from one another. They do not merge into one another and are not arranged helically around the rebar 1 .

figure 3 shows an embodiment of a reinforcement system 17 in the form of a reinforcement mat. The reinforcement system 17 has a multiplicity of reinforcement rods 1 which run parallel and perpendicular to one another and are connected in the form of a lattice by means of coupling elements 18 .

Additionally or alternatively, the reinforcing bars 1 can also run at an angle to one another, for example at an angle of 45° (not shown). The coupling elements 18 can according to the embodiment of figure 3 be formed, for example, as metal and / or plastic wires and / or sewing threads that connect the individual reinforcing bars 1. According to a preferred embodiment, a hot-melt adhesive is used as the coupling element 18, as is shown in 3 is indicated.

A building wall or a building ceiling made of concrete, for example, can be reinforced with the aid of the here two-dimensional reinforcement system 17 .

The present invention is not limited to the illustrated and described embodiments. Modifications within the scope of the patent claims are also possible.

Reference List

1

rebar

2

filament family

3

elevation

4

indentation

5

distance of elevations

6

width of the bumps

7

width of the indentations

16

plastic matrix

17

reinforcement system

18

coupling element

19a

first crush

19b

second crush

19c

third crush

X

Longitudinal extent/longitudinal direction

Y1

first transverse extent/transverse direction

Y2

second transverse extent/transverse direction

M

centerline

L

line along the rod surface

A

Distance between adjacent indentations

B

Broad

E1

first crushing direction

E2

second crushing direction

E3

third crushing direction

L1

first indentation line

L2

second indentation line

T

tetrahedron

Claims (15)

1. A reinforcing bar (1) for introducing into a concrete matrix, having at least one group of filaments (2) running in the length direction (X) thereof and made of a plurality of filaments embedded at least in segments, preferably completely, in a plastic matrix (16), the reinforcing bar (1) comprising protrusions (3) spaced apart from each other in the length direction (X) of the reinforcing bar (1) and indentations (4) spaced apart from each other in the length direction (X) of the reinforcing bar (1),
   the indentations (4) being implemented as compressions (19a-19c) of the at least one group of filaments (2) produced by forming tools, characterized in that the protrusions (3) are formed by filaments deflected laterally by said compression, wherein two or more indentations (4) spaced apart in said length direction (X) have a different orientation in the circumferential direction of the reinforcing bar (1).
2. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that two indentations (4) spaced apart in said length direction (X) have an offset angle to each other in the circumferential direction of the reinforcing bar (1) of greater than 0° and less than 180°, wherein the offset angle in the circumferential direction between indentations (4), particularly in the form of linear indentations (4), is preferably between 10° and 170°, particularly between 45° and 135°, preferably 90°.
3. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that the indentations (4) extend over the entire width of the reinforcing bar (1).
4. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that indentations (4) in succession in said length direction (X) are disposed separated from each other and/or do not transition into each other and/or do not extend all around the circumference of the reinforcing bar (1).
5. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that a pattern of successive indentations (4) repeats periodically along said length direction (X).
6. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that indentation lines (L1, L2) of the indentations (4) comprise an angle of inclination (α) to the length direction (X) between 10° and 90°.
7. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that the indentations (4) are disposed in the length direction (X) spaced apart at a distance (A) between 1 mm and 50 mm, preferably between 5 mm and 30 mm, particularly preferably between 10 and 20 mm, for example 15 mm.
8. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that the at least one group of filaments (2) is made of carbon fiber rovings, glass fiber rovings, and/or other high-performance rovings, preferably having a quantity of filaments of at least 12,000, advantageously of at least 48,000.
9. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that the reinforcing bar (1) comprises a plurality of protrusions (3) spaced apart regularly or irregularly from each other, the highest points thereof relative to each other being disposed along said line (L) running on the bar surface at a distance (5) between 1 mm and 100 mm, particularly preferably between 5 mm and 50 mm.
10. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that the cross-sectional area of the reinforcing bar (1) changes, preferably periodically, along the length (X) thereof.
11. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that said protrusions (3) and indentations (4) are based on a non-uniform density distribution of the filaments in the plastic matrix (16).
12. The reinforcing bar (1) according to at least one of the preceding claims, characterized in that at least a plurality of said protrusions (3) and indentations (4) are implemented as tetrahedrons or wedges, preferably oriented in varying directions, along the length (X) of the reinforcing bar (1).
13. A reinforcing system (17), wherein a plurality of reinforcing bars (1), which are implemented according to any one or more of the preceding claims, are connected by means of coupling elements (18) and thereby preferably reinforcing mats and/or reinforcing bar networks having reinforcing bars (1) offset to each other in the length direction (X) and/or transverse direction (Y) are implemented, the coupling elements (18) preferably comprising metal and/or plastic wires, sewing threads, and/or adhesives, particularly made of a duroplastic, thermoplastic, and/or elastomeric material.
14. A concrete component having a plurality of reinforcing bars (1) and/or at least one reinforcing system (17), each according to any one of the preceding claims, and a concrete matrix enclosing the reinforcing bars (1) and/or the at least one reinforcing system (17), the reinforcing bars (1) and/or the at least one reinforcing system (17) being positively anchored in the concrete matrix in a self-blocking manner, preferably additionally forming a force fit and/or material bond between the concrete matrix and the reinforcing bars (1) and/or the at least one reinforcing system (17), the at least one group of filaments (2) of the reinforcing bars (1) and/or the at least one reinforcing system (17) preferably running in the major loading direction of the concrete component.
15. A method for producing a reinforcing bar (1) according to any one of the claims 1-12 from at least one group of filaments (2) embedded in a plastic matrix (16), the method comprising the steps:

    - placing the at least one group of filaments (2) in a forming tool for producing the protrusions (3) and indentations (4), and/or passing the same through such a forming tool, the at least one group of filaments (2) already being present in a plastic matrix (16) or being introduced into the forming tool before or after the plastic matrix (16),

    - bonding the filaments of the at least one group of filaments (2) by applying at least pressure and optionally also heat in said forming tool, thereby forming protrusions (3) spaced apart from each other in the length direction (X) of the reinforcing bar (1) and indentations (4) spaced apart from each other in the length direction (X) of the reinforcing bar (1), wherein two or more indentations (4) spaced apart in said length direction (X) have a different orientation in the circumferential direction of the reinforcing bar (1).

Images