EP0505351B1 - Tensioning strand for prestressed concrete structures - Google Patents

Abstract

Tensioning strand consisting of a plurality of tensioning elements 1, such as for example rods, cords or wires, which extend parallel to one another and are covered by at least one common plastics sheath 2 preferably made of polyethylene or the like. In order that the tensioning strand requires only a small space in the support structure, the plastics sheath 2 tightly encloses the tensioning elements 1, which are connected tightly in contact with each other in an ordered configuration, the centre points of adjacent tensioning elements 1 lying at the corners of equilateral triangles or quadrangles. The interstices 4, 5 between the tensioning elements 1 can be filled with respect to one another by a permanently flexible compound, the compound also being able to penetrate between the tensioning elements 1 and the plastics sheath 2, so that the tensioning elements 1 can slide in the plastics sheath 2. In the process for manufacturing the tensioning strand, preferably a vacuum calibrator is used after the tensioning elements 1 have been guided in mutual contact through an extruder, or, if necessary, first through the permanently flexible compound. <IMAGE>

Description

The invention relates to a tension bundle for prestressed structures, in particular made of concrete according to the preamble of claim 1, and a method for its manufacture and installation.

US-A-3 646 748 discloses a tension bundle for prestressed structures made of concrete, consisting of several tension elements running in an ordered configuration and mutually touching, which are encased by a common shrunk-on plastic jacket, the tensioning elements being closely enveloped by the plastic jacket and the inner wall of the plastic jacket is tight against the outer tendons. The tension bundle can have any shape. It is provided that a permanently plastic mass fills the gaps and also penetrates between the clamping elements and the plastic jacket. Hiebei only a single clamping bundle is provided, which consists of several wires that are wound in a central wire, which has the disadvantage that only a limited clamping force can be achieved.

A similar tension bundle is also disclosed in US Pat. No. 4,623,504.

In the tension bundle according to EP-A-0 393 013, a plurality of tendons running parallel to one another are surrounded jointly by a plastic jacket. Due to the provided envelopes of the individual tendons themselves, the cross section of the described and illustrated tension bundles is somewhat larger than it should actually be. The enveloping plastic sheath is also further away from the individual tendons than would be necessary. The manufacturing process according to EP-A-0 393 913 comprises passing the tendons through an extruder, but there is no shrinking of the plastic jacket in order to achieve the smallest possible cross-section of the bundle in the end product and yet the mobility of the individual tendons in the bundle relative to that Allow coat.

In the tension bundle according to GB-A-1 394 382, the spaces between the tensioning elements are filled with one another by grease. Here it exists Tension bundles of several wires, which are arranged parallel to each other in a sheath. Wires have the disadvantage that they are relatively stiff and require a large diameter reel to wind up the tendons.

Furthermore, it is known to pull tensioning elements into a prefabricated cladding tube in a disordered manner and to press out the remaining free space with a lubricant, for example grease. However, only 50 to 60% filling of the cross section of the bundle can be achieved with tension bundles produced in this way, so that there is a relatively high space requirement with regard to the load capacity of the tension bundle.

In addition, the center of gravity of the clamping element arrangement does not coincide with the center of gravity of the casing or its geometric axis. In addition, changes occur at each deflection point, i.e. when the sense of curvature changes, the mutual position of the focal points.

For cables in which the individual tensioning elements are not parallel to one another but twisted in the bundle, it has been proposed ("Structural Engineering International", Volum 1, Number 1, February 1991, pp.61,62), the inner spaces between the wires to be filled with an anti-corrosion compound. The inner sheath is built on the wires. When this cable is tensioned, the outer sheath with the cable expands to the same extent. The problem of reducing the frictional forces between the arrangement of the tensioning elements and the jacket is not addressed.

In the prestressing member according to AT-PS 269 439, essentially linearly arranged and mutually parallel sub-elements are provided, which, however, are non-positively and shear-proof connected to each other. These binders, for example a Metal adhesive, fills the spaces between the sub-elements, but there is no plastic sheath that co-surrounds the sub-elements. The problem of the choice of distance between the individual sub-elements is not addressed, and the problem of the frictional forces between the clamping elements and a jacket remains unsolved.

In the construction according to EP-A-0 160 135, the tendons of the bundle cannot move relative to the plastic sheath enveloping them. Rather, for this purpose, a sliding layer must be provided outside of the plastic jacket and, radially thereafter, a jacket again, the tendons, together with the jacket surrounding them, being able to move within the outer jacket. In addition, the outer tendons of the tension bundle described are arranged twisted around a central tendon, so that there are disadvantageous changes in shape, in particular changes in the cross section of the tension bundle, when the pretension changes.

A tendon with twisted sub-elements is also described in WO-A-85/05394, which is not a pure tension bundle, but a Reinforcing element for prestressed concrete structures. This reinforcement element consists of a combination of one or more tendons of conventional reinforcement bars and at least one spiral bar provided between them as a spacer. With this design, the above-mentioned disadvantageous cross-sectional changes of the reinforcement element also occur with changing prestressing, and neither a minimization of the space requirement nor a reduction in the frictional forces between the tensioning elements and a jacket enveloping them is discussed.

The latter also applies to EP-A-0 105 839, in which it is only described that it is known to provide clamping elements with a two-layer plastic covering. This document then goes into more detail on the choice of material for the plastic sheathing, but does not deal with minimizing the space required to reduce the friction between the tensioning elements and the jacket, and maintaining the shape and geometry of the tensioning bundle.

EP-A-0 095 413 only addresses the sub-problem of the sliding ability of the tendons with respect to a cladding tube, which can also be made of plastic. However, the latter document gives no indication of how the problem of reducing the friction can be solved at the same time as minimizing the space requirement and maintaining the shape and geometry of a tendon consisting of several individual tendons.

The object of the present invention is to provide a tensioning bundle which avoids the above-mentioned disadvantages while minimizing the space requirement as much as possible, at the same time reducing the friction and maintaining the shape and geometry of the bundle in any position, and wherein tensioning elements can also be tensioned individually or in groups and can be turned on a reel with a relatively small diameter.

The measure according to the characterizing part of patent claim 1 serves to solve this problem.

Due to the permanently plastic mass between the clamping elements themselves and in particular between the clamping elements and the plastic jacket, the friction is largely reduced, the clamping, also individual and especially the outermost clamping elements, is made easier, all advantages of the compact parallel bundle being retained. The feature of claim 2 can also serve the corrosion protection of the clamping elements. A thickness of one or a few »m at the points of contact between the tensioning elements or these and the plastic jacket is sufficient for the desired smooth tensioning of the elements.

Sliding masses, e.g. environmentally friendly, especially water-compatible fats, preferably based on silicone or mineral oil, or natural products, e.g. rape-based.

The tensioning elements are advantageously held together, as a result of which the geometric configuration of the bundle is even more stable preserved. This also prevents the clamping elements from striking against one another or against the inner wall of the plastic jacket, so that the risk of damage is further reduced.

Claim 4 offers an advantageous variant.

In order to ensure that the tensioning elements in the casing can move as freely as possible, claim 5 serves as a result of this additional feature, on the one hand a better and more precise guidance of the outermost tensioning elements also between any provided enveloping elements and a reduction in the necessary amount of permanently plastic mass.

Of course, the clamping elements can be protected against corrosion individually or in groups, for example by means of a plastic covering or a galvanic coating.

The clamping bundle described is advantageously produced in a method which is carried out according to the preamble of claim 6. Such a method is essentially known from FR-A-2 610 656. The object of the invention is to take measures that during the subsequent cooling and shrinking of the plastic jacket, this leaves the clamping elements sufficient space so that the elements can slide in the jacket. These measures are met by the characterizing part of claim 6.

According to this manufacturing process, the tension bundle is produced in the configuration which has the smallest possible space requirement and by sucking the plastic jacket onto the inner wall of the calibrator it is achieved that the jacket is expanded to such an extent that it only cools in one in the subsequent cooling and associated shrinkage Dimensions become narrower that the internal clamping elements still have enough freedom to slide against the plastic jacket. The jacket must therefore be widened to such an extent that its inner wall does not lie so tightly in the finished clamping bundle in order to prevent the clamping elements from sliding. The exact extent of the expansion required depends on the material of the plastic jacket used, since different plastics can have different shrinkage coefficients. The above mentioned friction or Adhesion coefficient of the plastic material compared to the material of the tensioning elements influences the necessary expansion of the plastic jacket. Materials with a very low coefficient of friction or adhesion can be pressed more firmly against the clamping elements than those with a high coefficient. While slight widening is possible in the former case, in the second case the plastic jacket must be sucked out so far that the tensioning elements are relatively loosely enclosed after the subsequent shrinking of the jacket.

Depending on the area of application for the finished clamping bundle or the desired procedure in relation to a subsequent squeezing of the space between the clamping elements with different substances, it can be provided that the clamping elements are passed through the extruder dry or with a thin layer of a permanently plastic mass .

If the tensioning bundle according to the invention is to be designed in such a way that the spaces between the tensioning elements are to be filled with a permanently plastic mass and this mass is also intended to surround the tensioning elements, according to claims 6 and 7, the manufacturing process.

The measure according to claim 8 serves to facilitate the guiding of the tensioning elements and to be able to include the configuration with the smallest space requirement even when the tensioning bundle is finished.

The tension bundle according to the invention is preferably installed according to claim 9. Then the clamping elements can be anchored according to claim 10 or 11.

The measure according to claim 12 can be provided as one of the last process steps in the installation of the tension bundle according to the invention.

When using a permanently plastic mass, it is possible, as stated, to compress the tension bundle both before and after tensioning, which is why this option is mainly used where the tensioning elements have to be re-tensioned after the first installation, or their pretensioning is reduced if necessary should. The second specified possibility of pressing with a hardening mass will be used in those cases in which the tension bundle is not subjected to any change in the prestressing forces over the entire service life.

The tension bundle according to the invention is advantageously used according to claims 13 and 14.

In the following description, two exemplary embodiments of the tension bundle according to the invention will be described in more detail with reference to the accompanying drawings.

• Fig. 1 das erfindungsgemäße Spannbündel mit im wesentlichen kreisförmigen inneren Querschnitt des Kunststoffmantels,
• Fig. 2 das gleiche Spannbündel der Fig. 1, jedoch mit einem umhüllenden Element,
• Fig. 3 eine Variante, bei welcher der Kunststoffmantel in die äußeren Zwischenräume der Litzen eindringt,
• Fig. 4 ein Spannbündel mit einem umhüllenden Element der Litzen, in einer Ausführung entsprechend der Fig. 3,
• Fig. 5 bis 16 verschiedene Varianten des erfindungsgemäßen Spannbündels mit unterschiedlichen Anzahlen und Anordnungen der einzelnen Litzen,
• Fig. 17 eine Umlenkstelle im Tragwerk mit drei Spannbündeln,
• Fig. 18 einen Schnitt nach der Linie XVIII-XVIII der Fig. 17 und
• Fig. 19 bis 21 drei Varianten der Anordnung von Spannbündeln, z. B. nach den Fig. 9, 12 und 16.

Show

• 1 is the tension bundle according to the invention with a substantially circular inner cross section of the plastic jacket,
• 2 the same tension bundle of FIG. 1, but with an enveloping element,
• 3 shows a variant in which the plastic sheath penetrates into the outer spaces between the strands,
• 4 shows a tension bundle with an enveloping element of the strands, in an embodiment corresponding to FIG. 3,
• 5 to 16 different variants of the tension bundle according to the invention with different numbers and arrangements of the individual strands,
• 17 a deflection point in the structure with three tension bundles,
• Fig. 18 is a section along the line XVIII-XVIII of Fig. 17 and
• 19 to 21 three variants of the arrangement of clamping bundles, for. 9, 12 and 16.

In the drawings, 1 denotes the individual tensioning elements of the tensioning bundle. The individual tensioning elements 1 are constructed from strands. Envelopes of the clamping elements 1 or groups thereof are also possible, in particular made of plastic or by means of galvanic coating, in order to ensure corrosion protection for every individual element or group of elements.

All clamping elements 1 are surrounded by a common plastic jacket 2. This is preferably made of polyethylene or a similar material. In the illustrated exemplary embodiments, the configuration of the tensioning elements 1 is selected such that a ring of six outer tensioning elements is arranged around a central tensioning element. In this case, the centers of three adjacent clamping elements 1 form an equilateral triangle.

For certain areas of application, however, it may also be necessary to provide configurations that deviate from this arrangement, in which the centers of all the clamping elements 1 lie on a straight line or four clamping elements in each case in the corners of a square or a rectangle. For example, only three adjacent tensioning elements 1 could be arranged in such a way that their centers form, for example, an equilateral triangle (FIG. 5). The simplest arrangement results from two clamping elements lying side by side. In this case, the tension bundle forms a flat band (FIG. 6). However, three (FIG. 7), four (FIG. 8) or several clamping elements can also be arranged in a row lying side by side. Furthermore, two or more rows of clamping elements lying one above the other are also conceivable. For example, a clamping bundle is shown in FIG. 9, in which four clamping elements form a square.

In a corresponding manner, however, two rows of three (FIG. 10), two rows of four (FIG. 11) or two rows of any number of adjacent clamping elements can also be arranged one above the other. Of course, arrangements of three (FIG. 12, FIG. 13) or a plurality of rows of clamping elements lying one above the other are also possible. There is in principle no limit to the number of possible clamping elements 1, so that essentially any number of clamping elements in all possible geometric configurations can be combined to form a clamping bundle according to the invention. For example, several concentric rings of clamping elements are also possible. For example, two wreaths as shown in Fig. 14. However, a triangular arrangement, as in FIG. 5, can also be supplemented by a further outer ring of clamping elements, so that, for example, the arrangement shown in FIG. 15 results (in FIGS. 5 to 15 only the schematic arrangement of the clamping elements 1 is shown Shown in the tension bundle without going into the structure according to the invention. Of course, the features according to the invention are the sliding mass penetrating between the casing 2 and the tensioning element 1 or the additional features provided negotiate all these statements). Another variant is shown in FIG. 16.

In any case, the geometry of the tension bundle remains, i.e. the relative position of the centers of gravity of the clamping element arrangement and the sheathing, or the like, even in the case of deflections. receive.

The clamping elements 1 touch each other as shown in Fig. 1, i.e. the tensioning elements 1 are arranged as closely as possible in the tension bundle. The gaps between the clamping elements are filled by the permanently plastic mass mentioned at the beginning.

The inner wall 3 of the plastic jacket 2 is essentially circular in cross-section. It lies tightly against the outer tensioning elements 1. However, this tight contact of the jacket 2 with the tensioning elements 1 occurs only to such an extent that the relative mobility of the tensioning elements 1 relative to the plastic jacket 2, for example in the case of tensioning the tensioning elements, is maintained. The force with which the inner wall 3 of the casing 2 is pressed against the tensioning elements 1 must not exceed the value at which the coefficient of friction or adhesion between the two components 1, 2 becomes so great that no more displacement is possible. To reduce the said coefficient, a permanently plastic mass can of course also be provided, this mass forming at least one film which has penetrated between the outermost elements 1 and the jacket 2 and has a thickness of at least one or less »m. Between each of the two outermost clamping elements 1 there is an intermediate space 5 which, in the case of an essentially circular outer cross section of the clamping elements, has a gusset outline. These gusset-shaped spaces 5 and the inner spaces 4 between the individual tensioning elements 1 can be filled with the previously mentioned permanently plastic mass.

In the case of differently designed tensioning bundles with regard to the outer contour of the individual tensioning elements 1 or their configuration in the tensioning bundle, it can be provided that the plastic jacket 2 only fits tightly on some of the outermost tensioning elements 1. As an example, only one arrangement of tensioning elements is mentioned here, in which a plurality of concentric rings are arranged around a central element, and in which an essentially hexagonal arrangement ultimately results. If the inner wall 3 of the plastic jacket 2 is in the shape of an ice sheet, it will only fit snugly against the six clamping elements 1 which are at the greatest distance from the central element. Even in the case of triangular configurations of the clamping elements 1, this applies analogously to the three outermost clamping elements 1 which form the corners of the triangle.

2 shows a variant of the tensioning bundle according to the invention described above, the tensioning elements 1 now being held by an enveloping element 7 in the closest possible arrangement in which they touch one another. This variant also offers advantages in the manufacture of the tensioning bundle, since the individual tensioning elements 1 already during the passage through the extruder for applying the plastic jacket 2 to the tensioning elements 1 or through the anti-corrosion compound, in order to fill the spaces 4 and 5 with said mass , are kept in the desired configuration. The tensioning elements 1 therefore do not have to be subsequently compressed by additional devices in order to obtain the desired tight arrangement or to press excess lubricant out of the tensioning bundle, but rather the tensioning elements 1 with the mass located thereon can be introduced directly into the extruder.

Another variant is shown in FIG. 3. Here, the inner wall 3 of the plastic jacket 2 also adjoins the outermost clamping elements 1 at any point along the circumference. However, the plastic jacket 2 fills at least part of the mostly gusset-shaped gaps that are delimited by the outermost clamping elements by protrusions 6 at least partially. However, since the tensioning elements 1 lie close to one another, the material of the plastic jacket 2 cannot penetrate between the outermost tensioning elements 1, so that all the interstices 4 within the outermost ring of tensioning elements 1 continue to be filled only by the sliding compound. Of course, an enveloping element 7 can also be provided in this variant, as shown in FIG. 4.

To produce the above-described tension bundle or the above-described embodiments, the procedure can advantageously be such that the tensioning elements 1 are passed through an extruder in which the plastic jacket 2 is applied so as to touch one another. The use of extruders to apply jackets is a common technique. However, in order to achieve or achieve a sufficient degree of freedom for the tensioning elements 1 with respect to the inner wall 3 of the plastic jacket, that the plastic jacket 2 with its inner wall 3 does not lie so tightly against the tensioning elements 1 in order to prevent the relative displacement of these components against one another , the next step in the process is to guide the tension bundle with the still heated plastic jacket into a vacuum calibrator. In this device, the jacket 2 is sucked onto the wall of the calibrator by creating a vacuum, so that during the subsequent cooling and shrinking of the plastic jacket, the clamping elements leave enough space for the elements 1 to slide in the jacket 2.

When carried out by the extruder, the clamping elements can, if desired, be surrounded dry or by means of any application method with a thin layer of a permanently plastic mass. For example, such a mass could be provided by spraying on each individual clamping element or the final configuration of the clamping elements.

According to a modification of the manufacturing method according to the invention, however, it is also possible to proceed in a manner in which the clamping elements are guided in contact with one another through the permanently plastic mass, the mass penetrating into the inner and outer intermediate spaces of the clamping elements 1. Then the clamping elements 1 are passed together with the mass located thereon through an extruder in which the plastic jacket is applied. The gusset-shaped interstices are first filled with the permanently plastic mass, and in the extruder the extrusion of the plastic casing 2 can then be controlled in such a way that either the outer interstices only remain filled with the sliding compound, or that the material of the plastic casing 2 also has at least partial projections 6 forms, which at least partially fills the outer spaces. Of course, this possibility also exists for the method described first.

In the second case, the mass penetrates between the outermost clamping elements 1 and the inner wall 3 of the casing 2, so that the clamping elements 1 are slidable in the casing 2 and are surrounded on the outside by at least one film of the sliding compound.

In order to keep the tensioning elements 1 in a configuration, especially during the manufacture of the tensioning bundle according to the invention, in which the individual elements 1 touch each other, it can advantageously be provided that the tensioning elements 1 already during the passage through the extruder in the first manufacturing process or in second case are held together by the permanently plastic mass by at least one enveloping element 7. For this purpose, for example, a film or a mesh made of plastic or steel mesh can be used, which, however, is also attached during the passage of the mass or the extruder or after the tensioning bundle has passed through the mass.

The given as an example of such an element 7 network has the advantage that it prevents the penetration of the sliding mass in the Spaces between the tensioning elements are not hindered, and even have a certain restraining effect for the portion of the mass which fills the outer spaces 5. As can be seen from Figure 4, the enveloping element 7 in its design as a net-like structure allows the projections 6 of the plastic jacket 2 to penetrate through the element 7 and thereby establish a firm connection between the enveloping element 7 and the jacket 2, while the tensioning elements 1 remain slidable. In this embodiment, the element 7 also takes on the function of a stabilizing “reinforcement” of the plastic jacket 2.

When installing the tensioning bundle, the complete and factory-made, if necessary already cut to length, bundle can be drawn in, whereupon the tensioning elements are tensioned together to the desired value using a tensioning press. The parallel bundle has the additional advantage that the tensioning elements can also be tensioned in groups or individually, because due to the construction according to the invention the tensioning elements 1 are easily movable relative to one another and relative to the plastic jacket 2. The anchoring in anchor bodies is preferably carried out using wedges for each clamping element separately. It is possible to anchor several tension bundles in a common anchor body or in individual anchor bodies.

The tension bundles can also be summarized in different configurations, such as. B. FIGS. 19 to 21 show in which square tension bundles, such as those shown in FIGS. 9, 12 and 16, are selected, the individual bundle being designated by 10.

At the deflection points in the structure, 10 hard intermediate layers, e.g. B. made of sheet metal or the like. In the deflection point shown in FIGS. 17 and 18, 11 denotes a deflection saddle on which three band-shaped clamping bundles 10, each consisting of four clamping elements, rest, between which one hard intermediate layer 12 is arranged. Between the possible deflection points, the tension bundles are preferably combined into a group of bundles touching one another.

Of course, various design changes can be made within the scope of the invention. So there is the possibility to use the tensioning elements dry or to cover them only with a hint of permanently plastic mass, so that the sliding properties of the tensioning elements within the plastic jacket is guaranteed. In the usual way, the space between the tensioning elements or between the tensioning elements and the inner wall of the plastic jacket can be pressed with a hardening mass, preferably cement, after the tensioning elements have been tensioned. In this case, a further change in the pretension is prevented by the hardening of the mass and the firm embedding of the tensioning elements in it. If, on the other hand, it is provided or desired that the pretensioning of the tensioning bundle should also be changed after the first installation and the first clamping, it can be provided as an alternative to the first-mentioned possibility that the tensioning bundle before or after tensioning with a permanently plastic mass, preferably grease, to squeeze.

Claims (14)

1. Tensioning bundle for prestressed structures, in particular made of concrete, the tensioning bundles comprising a plurality of tensioning elements in an ordered configuration and in mutual contact, whose centre-points lie at the corners of equilateral triangles or of rectangles or on a straight line, and which are sheathed by at least one common, shrunk-on plastic sheath (2), preferably of polyethylene, the gaps (4, 5) between the tensioning elements being filled by a permanently flexible compound which has also penetrated between the tensioning elements and the plastic sheath (2), which plastic sheath (2) surrounds the tensioning elements, enclosing them tightly, characterized in that the tensioning elements comprise strands (1) extending parallel to one another.
2. Tensioning bundle according to Claim 1, characterized in that the strands (1) are protected against corrosion individually or in groups by a surface coating, for example by a plastic sheathing or a galvanic coating.
3. Tensioning bundle according to Claim 1, characterized in that the strands (1) are held together by at least one sheathing element (7), for example a film or a net of plastic or steel, within the plastic sheath (2).
4. Tensioning bundle according to Claim 1, characterized in that the plastic sheath (2) at least partially fills at least some of the gaps (5), which are bounded on the outside by the outermost strands (1) and are usually gusset-shaped, by means of projections (6).
5. Tensioning bundle according to Claim 1, characterized in that materials having the lowest possible friction coefficient compared to the material of the tensioning elements (1) are selected for the plastic sheath (2).
6. Method for the manufacture of a tensioning bundle according to Claim 1, the strands (1) being passed in parallel through an extruder in which the plastic sheath (2) is applied, the tensioning bundle subsequently being guided with the still heated plastic sheath into a vacuum calibrator, the plastic sheath (2) being sucked onto the wall of the vacuum calibrator by generating a vacuum, such that, during the subsequent cooling and shrinking of the plastic sheath (2), the latter leaves the strands (1) sufficient room for them to be able to slide in the plastic sheath (2), characterized in that the strands (1) are surrounded by a thin layer of a permanently flexible compound prior to introduction into the extruder.
7. Method according to Claim 6, characterized in that the strands (1) are guided in parallel and in mutual contact through the permanently flexible compound, the latter penetrating into the gaps (4, 5) and surrounding the strands (1), whereupon the latter are passed jointly and together with the permanently flexible compound through the extruder.
8. Method according to one of Claims 6 or 7, characterized in that the strands (1) are surrounded by a sheathing element (7).
9. Method for installing a tensioning bundle according to one of Claims 1 to 5, characterized in that the complete tensioning bundle is drawn into the structure or applied to the latter and the strands (1) are tensioned jointly, possibly in groups or individually.
10. Method according to Claim 9, characterized in that the strands (1) are anchored individually using wedges in anchoring bodies.
11. Method according to Claim 10, characterized in that a plurality of tensioning bundles are anchored in a common anchoring body.
12. Method according to one of Claims 9 to 11, characterized in that the end of the tensioning bundles is compressed before or after tensioning with a permanently flexible compound, preferably with grease or after tensioning with a curing compound, preferably cement.
13. Use of the tensioning bundles according to at least one of Claims 1 to 5 for inner or outer pretensioning arrangements in a structure made of concrete using a plurality of such tensioning bundles between which intermediate layers of hard material are inserted at any deflection points present, the ends of the tensioning bundles being anchored in a common anchoring body or in separate anchoring bodies.
14. Use of tensioning bundles according to Claim 13, characterized in that a plurality of tensioning bundles are combined between the deflection points to form a group of mutually contacting bundles.

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