EP0025856A2 - Device for anchoring the end of at least one rod of fibrous composite material used as a tensioning member in prestressed concrete constructions - Google Patents

Abstract

A device for the end anchoring of rods made of fiber composite material used in prestressed concrete construction is specified, with an anchoring hollow body which is penetrated by one or more rods in the longitudinal direction and can be fixed on the prestressed concrete component and which also contains a clamp body penetrated by rod, on which by means of a clamping device shear forces required for frictionally fixing the rods can be exerted. A longitudinal / lateral force conversion device, which converts tensile forces acting in the longitudinal direction of the rods into lateral forces proportional to them, comprises a lateral force limiting device with which a predeterminable amount of the lateral forces can be set, for which e.g. an upper limit can be specified by a spring-elastic limit value element or a compressible buffer body. By using squeezable clamping bodies, an even distribution of the tendons over their anchoring length is achieved, thus ensuring a safe and yet gentle anchoring of the same. In a special design of the device, blind rods inserted into the anchoring hollow body can be used to set a specific longitudinal / lateral force conversion ratio.

Description

The invention relates to a device for the end anchoring of at least one rod made of fiber composite material used as a tendon in prestressed concrete construction, with an anchoring hollow body which can be fixed on the prestressed concrete component and in which a clamping body which extends over a longitudinal section of the rod and is penetrated by the rod is arranged on the lateral forces acting by means of a clamping device acting at right angles to the longitudinal axis of the rod and imparting a frictional connection between the rod and the clamping body or the anchoring hollow body, the clamping body being part of a longitudinal force / transverse force conversion device with which the device introduced into the device in the longitudinal direction of the rod Forces which are proportional to the transverse forces which impart the frictional connection between the rod and the clamping body can be transformed.

Rods made of fiber composite materials - glass or carbon fibers cast into a resin matrix - have a high tensile strength or breaking strength in the longitudinal direction of the fiber, which is around 1600 N / mm ² for glass fiber composite (GV) rods. Therefore, instead of the usual prestressing steel, they can basically be used as tendons in prestressed concrete construction. However, the problem is the end anchoring of the GV-Spann under high prestress links because their resistance to lateral pressure and shear is significantly lower compared to steel bars. Of the end anchoring devices known in connection with steel rods, therefore, those which can be used in connection with GM tendons are those which have a frictional fixation of the GM tendons in a suitable anchor body, which in turn is supported or anchored on the concrete component in a tensile manner, convey; Such anchoring devices are, for example, wedge anchors and casting anchors with an internally conical anchoring body supported on the concrete component and penetrated in the longitudinal direction by the tendons, which in turn are attached to the anchoring hollow body by means of a generally multi-part in the case of wedge anchoring, in the case of potting anchoring as a one-piece potting cone are set, the transverse pressure of the clamping body and the tendons themselves required for the frictional fixing of the GM tendons being achieved by sufficient displacement of the clamping body in the longitudinal direction of the anchoring.

• die über die Spannglieder in die Endverankerung eingeleitete Zugbeanspruchung, die sich im allgemeinen additiv aus der den Spanngliedern erteilten Vorspannung und dem aus der Belastung des Spannbetonteils resultierenden Lastanteil zusammensetzt, verursacht eine Verschiebung des Klemmkörpers im Verankerungs- Hohlkörper, die ihrerseits zu lastabhängigen Querpressungen der Spannglieder führt. Diese Querpressungen sind im Regelfall sehr hoch und können bei GV-Stäben zu einer entscheidenden Minderung der langzeitig ertragbaren Verankerungskraft führen.

However, the end anchorings of GM tendons achieved with such devices have a number of significant disadvantages in view of the fact that the strength of the GM tendons decreases due to the breaking criteria applicable to them due to transverse and / or longitudinal shear stresses:

• The tensile stress introduced into the end anchorage via the tendons, which is generally additively composed of the prestressing imparted to the tendons and the load component resulting from the load on the prestressed concrete part, causes a displacement of the clamping element in the anchoring hollow body, which in turn leads to load-dependent transverse pressures of the tendons . As a rule, these transverse pressures are very high and can lead to a decisive reduction in the long-term tolerable anchoring force with GM bars.

It is in principle possible to keep such load-dependent transverse pressures within reasonable limits by providing a large anchoring length of the tendons and, within the relevant limit sliding angle, the steepest possible inclination of the conical inner surface of the anchoring hollow body or correspondingly large wedge or cone angles of the clamping bodies ; Such an anchoring device, however, becomes disproportionately bulky, especially if it is designed for a bundle comprising a plurality of tendons, so that its use for slim components becomes problematic. The transverse and shear stress peaks occurring at the beginning of the anchoring section, where the full longitudinal tensile stress is effective, which are correspondingly higher in view of the lower modulus of elasticity of the GM tendons compared to steel rods, are particularly harmful with GM rods. In addition, in the case of potting anchors in which there is a potting cone filling the anchoring hollow body as the clamping body and in which the tendons are embedded, this potting cone no longer resembles the conical inner shape of the anchoring hollow body due to the shrinkage of the potting compound which generally occurs is because there are larger absolute shrinkage amounts at the larger diameter than at the smaller one. As a result, the load-dependent transverse pressures on the tendons in the area of the smaller diameter of the casting cone, i.e. additionally enlarged on the entry side of the tendons.

The object of the invention is therefore to provide a device of the type mentioned at the outset which enables a gentle anchoring of GM tendons and thus a better utilization of the specific tensile strength of such tendons.

This object is achieved in that the longitudinal force / shear force conversion device has a shear force Contains limiting device with which a predeterminable amount of the transverse forces can be set. This setting of the transverse forces in the sense of a limitation to the amount that the cross-pressure-sensitive GM materials can withstand for a long time, but which on the other hand is chosen as high as possible so that one can get by with the shortest possible anchorage lengths, as in a preferred embodiment of the device according to the invention provided, thereby achieved that at least one limit element is provided in the context of the force conversion or limiting device, through which an upper limit of the transverse force can be predetermined, so that the transverse pressure of the tendon or, if necessary, several span members anchored with the device according to the invention, the said barrier cannot exceed.

An anchoring device suitable for this purpose is realized according to one embodiment of the invention in that the force-converting device, as a limit value element, has a tensioning element which can be actuated from the rod exit side of the anchoring hollow body and with which one is directed parallel to the longitudinal direction of the tendon or the hollow body Tension force defined amount is adjustable, the implementation of which results in the transverse forces imparting the frictional fixation of the tendon.

The particular advantage of the device according to the invention is that its tensioning element in the arrangement according to the invention is easily accessible from the outside even when the anchoring head is inserted into the recess provided for receiving it in the concrete, so that the setting of the required clamping force is already sufficient is significantly simplified. A precise setting and distribution of the clamping force is ensured by the force transmission device arranged in the interior of the anchoring head. It is sufficient - in principle at least - if only a single die Power transmission device acting clamping element is provided, so that the work required to set the clamping force is low and otherwise a simple structure of the device is achieved.

A power transmission device provided with wedges according to the invention enables a well-defined setting of the transverse pressure on a relatively small displacement movement of the wedges. The tensioning element can be designed so that a re-tensioning, e.g. done by one or more preloaded Belleville washers.

In the design with mutually braceable wedge plates as a force conversion and introduction device, it is expedient if the hollow body has a right-angled square cross section and flat rod-shaped tendons are provided which are arranged between clamping plates, a plurality of such tendons and clamping plates alternating in a sandwich -like structure between the wedge plate arrangement and one of the outer walls of the hollow body can be arranged. It goes without saying that such sandwich structures can also be provided on both sides of the wedge arrangement.

A design of the device according to the invention is particularly advantageous in which the flat bar-shaped tendons are also enclosed on their longitudinal edges by the clamping plates and thus counteracts a fraying of the tendons on their longitudinal edges.

In the case of the right-angled-quadrangular cross-sectional shape of the hollow body, it is also possible in a simple manner to achieve transverse pressures in two directions perpendicular to one another with the aid of two wedge plate arrangements. It is then also possible to uniformly press tendons with a square cross-section.

In the event that these forces are to be absorbed into the hollow body on the entry side of the tendons, it is sufficient to support the clamping plates on the inside of an abutment plate firmly connected to the hollow body there.

According to a further embodiment of the device according to the invention, the longitudinal force / shear force conversion device comprises a conical sleeve which extends in the longitudinal direction of the anchoring hollow body and can be expanded by driving in a truncated cone-shaped wedge body, and as a tensioning element a longitudinally penetrating the wedge body between the outer base of the wedge body and the end face of the conical sleeve which acts on it and acts on the tie rod. When using this force transmission device, it is possible to fill the interior of the hollow body with a material that can be compressed in the radial direction, in which the tendons are embedded and that has sufficient strength for the force transmission in the longitudinal direction, it then no longer depending on the cross-sectional shape of the tension members arrives. The special design of the power transmission device results, as already mentioned, in radially directed transverse forces and correspondingly opposite reaction forces, so that the tendons are subjected to uniform transverse pressure on all sides, which ensures optimal anchoring.

In a preferred embodiment of the device according to the invention, the clamping body can be expanded radially by axial squeezing ^q and is arranged between a crushing plate on the inlet side and one on the outlet side, of which at least one plate is displaceably guided in the axial direction on an end section of the hollow body and is also defined by means of the clamping element - adjustable clamping force can be clamped against the other or pressed onto the expandable clamping or squeezing body, this body at least from a lower limit value of the prestressing and preferably already in the relaxed state in the area between the squeeze plates and between the tendon and / or others Parts of the clamping device arranged in the interior of the hollow body completely fill the remaining cavity.

With this design of the device according to the invention, which leads to a quasi-hydrostatic and thus particularly uniform distribution of the transverse pressure with a suitable choice of the material for the squeezable part of the clamping body, it is possible, in a distribution that is in principle arbitrary, that the clamping body in Assert in the axial direction, anchor it evenly and securely, whereby a single clamping element can be sufficient, or else two or more clamping elements that can be used in a preferably radially symmetrical arrangement.

If, in a further embodiment of the device according to the invention, the tendons are inserted in slotted clamping sleeves made of steel or another "hard" material, reliable anchoring of the tendons is ensured even if the squeeze body consists of a relatively "soft" material, since then the Clamping sleeves surrounding clamping elements ensure the force input into the hollow body or into the concrete surrounding it.

• 1. Es wird eine sprunghafte Zunahme der Querpressung an der Eintrittsstelle vermieden. Der Maximalwert der Querpressung wird, von der Eintrittsstelle aus gesehen, erst nach einer endlichen Länge erreicht. Durch die solchermaßen über einen, wenn auch relativ kurzen Längenabschnitt der Spannglieder verteilte Zunahme der Querpressung sind die Spannglieder gerade dort, wo ansonsten die maximale Belastung vorhanden wäre, "geschont", was sich günstig auf die erreichbare Zeitstandfestigkeit auswirkt.
• 2. Durch die einseitig zusammenhängenden und solchermaßen zu einem Block zusammengefaßten Klemmhülsen wird die Handhabung der Vorrichtung beim Zusammensetzen ganz wesentlich vereinfacht, insbesondere dann, wenn eine größere Anzahl von Spanngliedern vorgesehen sind.

According to a further embodiment of the device according to the invention, the sectors of the individual clamping sleeves are firmly connected to one another at one end and preferably on the entry side of the tendons. The main advantages are:

• 1. A sudden increase in the transverse pressure at the entry point is avoided. The maximum value of the transverse pressure, as seen from the entry point, is only reached after a finite length. As a result of the increase in transverse pressure distributed over a length section of the tendons, even though it is relatively short, the tendons are "protected" precisely where the maximum load would otherwise be present, which has a favorable effect on the creep rupture strength that can be achieved.
• 2. The one-sided connected and thus combined to form a block, the handling of the device when assembling is considerably simplified, especially when a larger number of tendons are provided.

According to one embodiment of the device according to the invention, the tendons are enclosed by a clamping body, which consists of a material with a sufficiently high strength for power transmission in the longitudinal direction, and the clamping body is enclosed on at least part of its outer surface by the squeezing body which can be expanded by squeezing.

This embodiment includes a design of the clamping body which is particularly suitable for a compact arrangement of a plurality of tendons. The block-shaped clamping body provided here can, depending on the material, be designed as a casting part, for example made of epoxy resin material, which may be reinforced by suitable fillers and / or fibrous materials, but also be made from a metal block, in the ver from the outlet end, preferably at right angles to each other running slots are sawn, which intersect the longitudinal links in the axle transmitter receiving the tension members. Such a clamping body is also suitable in connection with such embodiments of the device according to the invention in which wedge plates or the like which are braced against one another are used as the force transmission device.

In a further embodiment of the invention provided cladding foils for the tendons is reliably avoided that the surface roughness of the tendons, which is necessary with regard to a prestressing of the same in the prestressed bed, when the device according to the invention is used to achieve or maintain the prestressing of the bars , leads to peak loads that could cause the rods to break. The cladding foils are of course only required if hard clamping bodies or clamping sleeves are used. Alternatively, the tendons and / or the clamping sleeves can be provided with flexible coatings.

The device according to the invention is in principle also suitable for prestressing in the prestressing bed, because here too, anchoring of the tension members that is fully effective over a long period of time is required. Furthermore, the device according to the invention is also suitable for the end anchoring of rods, which can be used, for example, for bracing transmission masts, tent roofs and similar building structures.

It goes without saying that instead of the wedge arrangements used in individual embodiments of the device according to the invention in the context of its force transmission device, the squeeze bodies provided in further embodiments and deformable by axial squeezing can also be used.

Starting from a device of the type mentioned at the outset with an internally conical anchoring hollow body, the clear internal cross-section of which narrows towards the entry side of the tendon, and with an inside of the anchoring hollow body which is arranged directly and there against the tendon and which is radially supported on the conical inner lateral surface of the anchoring hollow body Clamping body, which experiences an axial displacement directed towards the prestressed concrete component under the influence of the prestressing impressed on the prestressing element and, as a result of this displacement, transmits the transverse pressure required for its frictionally anchored anchoring, according to a further embodiment of the invention the object stated at the outset is achieved in that that a stop device is provided as the limit element, which the axial displacement of the clamping body with a defined and for the required static friction between the clamping body and de m or the associated cross-tension sufficient for this tendon (s).

This gives at least the following advantages:

By said limitation of the displacement path permitted for the clamping body in the anchoring hollow body, which is expediently taken for safety reasons such that the transverse pressure of the clamping body and the GM tendons which is set is slightly greater than a minimum value which is absolutely necessary for secure anchoring, becomes simple avoided that the full amount of the tensile forces introduced by the tendons is converted into an excess transverse pressure that would only affect the breaking strength of the tendons. - 11 -

Very flat inclinations of the conical inner wall of the anchoring hollow body with respect to its longitudinal axis and correspondingly small wedge or cone angles can be selected for the clamping body, so that the transverse dimensions of the device according to the invention remain inexpensively small even if it is designed for very high clamping forces, which if necessary are entered into the hollow anchoring body using several single tendons. The use of a small inclination angle of approx. 2-5 ⁰ in the inner cone of the anchoring hollow body and correspondingly smaller wedge ratios or cone angles in the range of approx. 1:30 also has the advantage of a well uniform distribution of the transverse pressure over the anchoring length In addition, at small values, this angle can be given or specified very precisely by means of the stop device, because of the associated increase in the displacement of the clamping body relative to the anchoring hollow body, which provides the desired minimum amount of transverse compression of the clamping body and the tendons . check.

In addition, the described disadvantages of the shrinkage of the potting body are practically avoided by the small angle of inclination of the inner cone.

In a further embodiment of the device according to the invention, the anchoring hollow body is closed off at the tendon entry side with a plate, and on the inside of the plate a buffer body is provided, on which the clamping body can be supported in the axial direction. The one permitted by the buffer body and used to achieve the frictional connection Fixation necessary displacement path of the buffer body is here after an experiment measured experience or calculated from the design data of the device and the characteristic material values of the sprag. It goes without saying that the buffer body and the abutment plates of the anchoring hollow body must have aligned through openings for the GM tendons.

The inventive implementation of the buffer body as a rigid foam plate, which can be compressed under the longitudinal tensile force acting on the clamping body by the intended clamping body displacement path, is characterized by particular simplicity. However, it is also possible to design the buffer body as a steel plate which is displaceably guided in a cylindrical end section of the anchoring hollow body and which is supported by a resilient member on the abutment plate which closes the anchoring hollow body on the inlet side and is firmly connected to it.

Of particular advantage is a design of the device according to the invention in which the displacement path of the clamping body enclosing the tendons in the anchoring hollow body can be adjusted to exactly the amount required to achieve the most favorable transverse pressure. For this purpose, a stop plate limiting the displacement can be fixed from the start at a distance from the stop surface of the anchoring hollow body that corresponds to the intended displacement path of the clamping body; However, it is also possible in each individual case to adjust the displacement in a force-dependent manner, by lowering the tensile force on the clamping press by the difference to be absorbed by the anchoring hollow body while the clamping press is still in place and the clamping body is ready for retraction, taking into account the intended displacement of the clamping body, so that the clamping body experiences only this difference in the longitudinal tensile force retraction, after which the stop plate is fixed in its position preventing further displacement of the clamping body.

In a further embodiment of the device according to the invention it is provided that the tension nut of a tie rod is supported on the stop plate via a spring-elastic member, the restoring force of which corresponds to approximately half of its maximum spring travel of the tensile force to be absorbed. Even after the stop plate is fixed in its stop position, the clamping body can still be displaced in the direction of the acting longitudinal tensile force by a piece limited by the remaining spring travel of a partially prestressed spring-elastic element. As a result, a minimum transverse pressure required for fixing the tendons can also be maintained in the clamping body if the clamping body experiences a permanent volume reduction due to subsequent shrinkage or anelastic deformation, which would otherwise lead to a reduction in the transverse pressure. In this embodiment, the device according to the invention is particularly suitable for casting anchors.

In a further, special design of the device according to the invention, which results in a favorably uniform distribution of the transverse pressures resulting in the clamping body over the anchoring length of the tendons, the tendons to be anchored are held in the truncated cone-shaped encapsulating body in these longitudinally penetrating clamping sleeves which can be compressed in the radial direction are supported with radial flange pieces on the outside of a pressure plate which is arranged to be movable in the axial direction and which in turn rests directly on the exit-side base surface of the potting body and covers them except for an edge gap required for their axial displacement.

In this design of the device according to the invention, tensile forces acting on the tendons are entered into the clamping body via the pressure plate arranged on their outlet side, which due to its always present elasticity experiences an axial crushing which leads to a quasi-hydrostatic internal pressure in the clamping body and an even distribution the cross pressure over the anchorage length further favored. By suitable choice of the potting material, i.e. suitable specification of its mechanical properties, the conversion ratio with which load-dependent tensile forces are converted into transverse pressures proportional thereto can be varied within wide limits and set to a desired level. In particular, it can be avoided in this design of the device according to the invention that an edge gap between the casting body and the anchoring hollow body occurs due to a shrinkage of the casting body on the outlet side of the tendons, as a result of which this region would become ineffective for anchoring the tendons.

If, in a further embodiment of the device according to the invention, Klenmi sleeves are provided which have a jacket which is divided by radial longitudinal slots in preferably axially symmetrically arranged sectors and which is block-shaped or tubularly connected at its end section, an abrupt increase in the transverse pressure becomes effective at the entry point avoided. Rather, the maximum value of the transverse pressure, as seen from the point of entry of the tendons into the device, is reached after a finite length. Due to the increase in pressure distributed over a length section of the tendons, even if it is only a short length, the tendons are straight where the known tendon anchorages have the maximum tendon load, better "protected", which has a favorable effect on the creep strength that can be achieved. In addition, especially when a larger number of clamping sleeves are combined in a block connected on the inlet side, the handling of the device during assembly is considerably simplified. An advantageous design of a clamping sleeve body, which is particularly suitable for a crowded central arrangement of the tendons, can be realized in a further embodiment of the device in that the clamping sleeves are combined to form an overall block-shaped clamping sleeve body, which is crossed by longitudinal slots, the longitudinal center planes of which intersect in the axes of the tendons , the flexibility in the transverse direction of the tendons required for the transfer of the transverse pressure is granted.

In a further embodiment of the device according to the invention, it is provided that an effective limitation of the transverse forces which act on the tendons to be anchored is achieved by providing a design of the clamping device or the longitudinal force / lateral force conversion device which is very suitable for the setting or specific choice small implementation ratios allowed.

For this purpose, according to an embodiment of the device according to the invention it is provided that at least a part of the clamping body is designed as a body which can be compressed by the tensile forces acting on the tendons in the axial direction, for example by wedge action, in which in addition to tendons, in which the load in the case of Attack transverse forces converted tensile forces, other supporting bodies or blind rods corresponding to the tendons in terms of their mechanical properties and dimensions can be used and to which to anchor the Tendons can be fixed in an analogous manner in the clamping body.

Advantageous functional properties of the device according to the invention achieved in this way are at least the following:

By appropriately specifying the dimensions and material properties of the squeezable part of the clamping body, the increase in the load-dependent transverse pressure to which the tendons are exposed can be set to a defined value which can be varied within wide limits and thus limited to the extent permissible for the respective use. Furthermore, through the force input provided according to the invention, the tensile forces acting on the tendons _- load-dependent _- tensile forces via the squeeze plate arranged on the outlet side, which is displaceable in the axial direction, are achieved in the simplest way for re-tensioning of the clamping body under all conceivable conditions by specifying the number and dimensions of the additional support bodies, which take up the transverse pressures resulting from the tensile forces acting on the tendons and absorb some of these transverse pressures, the increase in the load-dependent transverse pressure to which the tendons are subjected can be set to a defined value which can be varied within wide limits and thus limit it in a simple way to what is permissible for the respective application.

It is also possible with known wedge or potting anchors to vary the transverse compression / tensile force ratio by suitable choice of the relevant wedge angle, although this variation possibility is limited by the fact that the wedge angle must be chosen to be smaller than the slip limit angle. The consequence of this is that a be minimum shear force / tractive force ratio cannot be undershot. In contrast, the device according to the invention has the advantage that such a limitation does not apply and, if necessary, very small shear force / traction reduction ratios can be achieved.

In a further embodiment of the device according to the invention, the effective shear force / tensile force reduction ratio can be predetermined in a simple manner by the numerical ratio of the tendons anchored in a wedge-body part of the clamping body. It goes without saying that this reduction ratio can also be influenced in the case of a two-part design of the clamping body in that, in the wedge body part of the clamping body, blind rods are used in addition to the tendons via which the effective tensile forces act. It is expedient if a radial or mirror-symmetrical arrangement of the tendons involved in the tractive force entry can be selected when replacing individual tendons with such dummy rods, or if the symmetry of the distribution of these tendons corresponds to the symmetry of the distribution of the tendons as a whole.

According to a further embodiment of the device according to the invention, it is expedient if an odd number of tendons arranged along a common plane and held between the flat wedges of the wedge clamping body part is provided, so that when individual tendons are replaced by blind rods, for example, an arrangement can be realized in which In each case, a dummy rod can be arranged between two tendons involved in the transmission of tensile force in order to achieve the most uniform possible force input into the end anchoring device.

A compensating layer provided according to the invention provides the advantage that a uniform distribution of the transverse pressure of the tendons, which are held between fixed clamping body elements which are movably held in the transverse direction, along the anchoring length of the tendons is also ensured to a sufficient extent if the walls conveying the lateral support of the clamping body a recess provided for this purpose in the concrete component or an anchoring hollow body receiving the clamping body does not extend exactly to the corresponding supporting surfaces of the clamping body.

As a rule, such a compensating layer will only be required if the clamping body is inserted into a recess in the concrete component, the compensating layer then being designed as an inner lining of this recess which compensates in particular for surface roughness and manufacturing tolerances of the recess.

A resilient adhesive layer provided according to the invention, which is embedded in the tendons, has the advantage that peak pressures caused by surface roughness of the tendons themselves and / or the clamping element elements, which could give rise to significantly higher values of the transverse pressure of the tendons, can be largely avoided. Rather, specifically applied surface roughnesses on the clamping element elements can be used to advantage for better adhesion of the tendons in the clamping body and thus as a result for a reduction in the minimum transverse pressure required for the secure fixing of the tendons. The adhesive layer present between the tendons and the clamping body elements, the manufacturing technology as a coating of the tendons itself or as a coating of the clamping body elements should, however, not be too thick, so that not too large displacement paths of the wedge members are required to achieve the minimum transverse pressure mentioned. It is therefore expedient if the layer thickness is only slightly greater than the surface roughness of the tendons or the clamping element elements which can be expressed in terms of diameter or distance difference.

In a further embodiment of the device according to the invention, a defined limitation of the load-dependent contribution to the transverse pressure is achieved by a suitable choice of the numerical ratio between tendons which are anchored in an externally conical, axially displaceable clamping body part and those tendons which are anchored in a central clamping body part, one in the anchoring hollow body forms a fixed sliding core for the outer clamping body part designed as a potting part. In this design, the device according to the invention of a potting-cone anchoring is largely analogous, although the core can also be made of a different material and, if appropriate, can be composed of metal cleat plates mutually supported by the tendons, with gaps remaining between the plates by a suitable sheathing should be covered to prevent penetration of the potting compound into the core clamping body.

According to a further embodiment of the device according to the invention, it is provided that the clamping body is designed as a body consisting of a material that can be expanded by squeezing and completely filling the anchoring cavity, that the at least one tensioning element is inserted in a clamping sleeve which is enclosed by the squeezing body and penetrates it. which with radial flange pieces on the outside of a longitudinally displaceable tendon, apart from a narrow marginal gap, supports the anchoring cavity on the outlet side of the tendon closing squeeze plate, and that a tensioning device is provided with which the clamping body by axially displacing the squeeze plate is used for the frictional fixation of the tendon under initial load required initial crush can be issued.

If, in a further embodiment of the device according to the invention, a cylindrical-pot-shaped anchoring hollow body is provided, which limits the anchoring cavity in the radial and to the entry side of the at least one tendon, which in turn is supported against the tensile forces acting on the tendon on the concrete component, which is fixed on the entry side of the tendon by a fixed is connected to the hollow body jacket, provided with a through opening for the clamping sleeve, the anchoring cavity is much easier to implement with a defined shape and surface quality of its inner walls than if the anchoring cavity is delimited by the concrete component itself.

This applies in particular if, according to a further design of the device, the anchoring hollow body on the outlet side of the tendon is significantly (approx. 1.5 to 3 times) larger over a partial length that corresponds to approximately 1/10 - 1/5 of the total length of the device Has inside diameter, as in its part closed off by the base plate, in such cases a recess of the concrete component receiving the anchoring body can then be used for the formwork of the same have a more favorable, simple shape, wherein between the anchoring hollow body and the walls of the concrete component recess remaining gaps can be pressed after attaching the device in order to hold the anchoring hollow body securely in its desired position.

• Fig. 1 eine speziell zur Endverankerung Flachstab-i.ürmi- ger Spannglieder geeignete erste Ausführungsform einer erfindungsgemäßen Vorrichtung, mit einer mit gegeneinander verspannbaren Keilplatten arbeitenden Kraftübertragungsvorrichtung und an der Austrittsseite der Zugglieder außenseitig abgestützten Klemmplatten, in einem Schnitt längs der vertikalen Längsmittelebene der Vorrichtung,
• Fig. 2 die Vorrichtung gemäß Fig. 1 von der Austrittsseite der Spannglieder.her gesehen,
• Fig. 3 den eintrittsseitigen Endabschnitt einer zur Vorrichtung gemäß Fig. 1 weitgehend analog aufgebauten zweiten Ausführungsform einer erfindungsgemäßen Vorrichtung, mit eintrittsseitiger Abstützung der Klemmplatten, in einer der Fig. 1 entsprechenden, abgebrochenen Schnittdarstellung,
• Fig. 4 eine mit zweiachsiger Eintragung der Querkräfte arbeitende dritte Ausführungsform einer erfindungsgemäßen Vorrichtung, in einer der Fig.2 entsprechenden Darstellung.
• Fig. 5a eine mit radialer Querkrafteintragung arbeitende erfindungsgemäße Vorrichtung mit als Konus/Kegel-Keilanordnung ausgebildeter Kraftübertragungsvorrichtung, in einer der Fig.1 entsprechenden Schnittdarstellung,
• Fig. 5b eine Ansicht der Vorrichtung gemäß Fig. 5a in einer der Fig. 2 entsprechenden Darstellung,
• Fig. 6a eine bevorzugte Ausführungsform einer erfindungsgemäßen Vorrichtung mit einem durch axiale Quetschung radial aufweitbaren Klemmkörper, in einer der Fig. 5a entsprechenden, teilweise abgebrochenen Darstellung, etwa im Maßstab 1:1,
• Fig. 6b eine Ansicht der Vorrichtung gemäß Fig.6a in einer der Fig.5 entsprechenden Darstellung und
• Fig. 7a zwei weitere bevorzugte Gestaltungen mit Quetsch-- 8b körpern zur Kraftübertragung versehener erfindungsgemäßer Vorrichtungen in der Fig. 6a bzw. 6b entsprechenden Darstellungen.
• Fig. 9 eine weitere Ausführungsform einer erfindungsgemäßen Vorrichtung im Längsschnitt, im Maßstab 1:1,5,
• Fig.10 eine weitere Ausführungsform einer erfindungsgemäßen Vorrichtung, in einer der Fig.9 entsprechenden Schnittdarstellung, ebenfalls im Maßstab 1:1,5,
• Fig.11 eine Ansicht einer erfindungsgemäßen Endverankerungsvorrichtung in Richtung des Pfeils 1 der Fig. 12 im Maßstab von ca. 1:2,
• Fig.12 die Verankerungsvorrichtung gemäß Fig.11 im Schnitt längs der Linie II - II, ebenfalls im Maßstab von ca. 1:2,
• Fig.13 eine spezielle Ausführungsform einer erfindungsgemäßen Endverankerungsvorrichtung für rundstabförmige Spannglieder aus Faserverbundstoff, mit einer mit gegeneinander verspannbaren Flachkeilen und Klemmplatten arbeitenden Kraft-Umsetzungseinrichtung, in einem Schnitt längs der Linie I-I der Fig.2,
• Fig.14 die Vorrichtung gemäß Fig.13 von der Austrittsseite der Spannglieder her gesehen,
• Fig.15 eine spezielle Abwandlung der Vorrichtung gemäß den Figuren 13 und 14 in einer der Fig.14 entsprechenden Darstellung und
• Fig.16 eine weitere spezielle Ausführungsform einer erfindungsgemäßen Endverankerungsvorrichtung mit einem insgesamt kegelstumpfförmigen, als Vergußteil ausgebildeten Klemmkörper,
• Fig.13 jeweils im Maßstab von ca. 1:2, - 16
• Fig.17 eine weitere Ausführungsform einer erfindungsgemäßen Endverankerungsvorrichtung in einem teilweise abgebrochenen Längsschnitt und
• Fig.18 eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung, in einer der Fig.17 entsprechenden Darstellung, jeweils im Maßstab von ca.1:1,5 bis 1:2

Further details and features of the invention emerge from the following description of exemplary embodiments with reference to the drawing. Show it:

• 1 shows a first embodiment of a device according to the invention which is particularly suitable for the end anchoring of flat bar-i.turret tendons, with a force transmission device working with wedge plates which can be braced against one another and with clamping plates supported on the outside on the exit side of the tension members, in a section along the vertical longitudinal center plane of the device,
• 2 seen the device of FIG. 1 from the outlet side of the tendons.
• 3 shows the entry-side end section of a second embodiment of a device according to the invention, which is largely analogous to the device according to FIG. 1, with support of the clamping plates on the entry side, in a broken sectional view corresponding to FIG. 1,
• 4 shows a third embodiment of a device according to the invention working with biaxial entry of the transverse forces, in a representation corresponding to FIG. 2.
• 5a shows a device according to the invention working with radial transverse force input with a force transmission device designed as a cone / cone wedge arrangement, in a sectional view corresponding to FIG. 1,
• 5b is a view of the device according to FIG. 5a in a representation corresponding to FIG. 2,
• 6a shows a preferred embodiment of a device according to the invention with a clamping body which can be expanded radially by axial squeezing, in a partially broken-away representation corresponding to FIG. 5a, approximately on a scale of 1: 1,
• 6b shows a view of the device according to FIG. 6a in a representation corresponding to FIG. 5 and
• Fig. 7a two further preferred designs with squeezing 8b bodies for power transmission of devices according to the invention provided in Fig. 6a and 6b corresponding representations.
• 9 shows a further embodiment of a device according to the invention in longitudinal section, on a scale of 1: 1.5,
• 10 shows a further embodiment of a device according to the invention, in a sectional view corresponding to FIG. 9, likewise on a scale of 1: 1.5,
• 11 is a view of an end anchoring device according to the invention in the direction of arrow 1 of FIG. 12 on a scale of approximately 1: 2,
• 12 shows the anchoring device according to FIG. 11 in section along the line II-II, likewise on a scale of approx. 1: 2,
• 13 shows a special embodiment of an end anchoring device according to the invention for round rod-shaped tendons made of fiber composite material, with a force conversion device working with flat wedges and clamping plates that can be braced against one another, in a section along the line II of FIG. 2,
• 14 the device according to FIG. 13 seen from the exit side of the tendons,
• 15 shows a special modification of the device according to FIGS. 13 and 14 in a representation corresponding to FIG. 14 and
• 16 shows a further special embodiment of an end anchoring device according to the invention with an overall frustoconical clamping body designed as a casting,
• Fig. 13 each on a scale of approx. 1: 2, - 16
• 17 shows a further embodiment of an end anchoring device according to the invention in a partially broken longitudinal section and
• 18 shows a further embodiment of the device according to the invention, in a representation corresponding to FIG. 17, in each case on a scale of approximately 1: 1.5 to 1: 2

The anchoring devices shown in FIGS. 1 to 18 are explained below with special reference to their use for permanent end anchoring of tendons made of fiber composite materials in prestressed concrete construction; but they can also, e.g. B. in connection with conventional tensioning presses, can be used as movably arranged drawing heads with which the tendon ends only have to be held over a relatively short period of time in order to set the required prestressing. A person skilled in the art can readily recognize other possible uses in which permanent or only temporary anchoring of tendons is generally required on the basis of the constructive and functional details of the individual exemplary embodiments to be explained.

FIGS. 1 and 2 show an end anchoring device 10 according to the invention for three flat bar-shaped tendons 11-13 made of glass fiber composite material in the special case example shown, which are arranged one above the other with a parallel course at a vertical distance. These penetrate an anchoring hollow body 14 of the device 10 designed as a steel hollow profile with a square 4x4 cm ² cross section in the longitudinal direction thereof.

The hollow body 14 is received by an outwardly open, cylindrical recess 16 of the concrete body 17 and is supported with a flange 18 provided at its outer end on the outer surface 19 of the concrete body 17 surrounding the opening of the recess 16. The cavity remaining between the hollow body 14 and the walls of the recess 16 is pressed with concrete or another suitable casting compound.

The tendons 11-13 are inside the hollow body arranged between the clamping plates 20-23 of steel or aluminum, whose effective thickness, at least in so far as they are disposed between the clamping members 11-13 _J corresponds to the vertical distance and the width thereof is slightly smaller than the inside diameter 14 of the hollow body are a total of four Clamping plates 20-23 are provided which form a sandwich-like stack with the tendons 11-13 in such a way that each tendon is arranged between two clamping plates, this stack being via its lowest clamping plate 20 according to FIG. 2 on the lower cross leg 24 of the hollow body 14 is supported. The clamping plates 20-23 have at their end portions emerging from the hollow body 14 laterally protruding, which cross the vertical profile legs 26 and 27 of the hollow body 14 according to FIG. 2, in cross-section approximately Hanunerkopf-shaped flange pieces 28, which on the outer end faces of the profile legs 26 and 27 lie directly and secure the clamping plates 20-23 against being pulled out of the hollow body 14 in the direction of the tension acting on the tendons 11-13.

Between the uppermost clamping plate 23 according to FIG. 3 and the upper cross leg 29 of the hollow body 14, two wedge plates 30 and 31 are arranged in the arrangement shown in FIGS. 1 and 2, to the details of which express reference is made, between the vertical profile legs 26 and 27 Can be moved in the longitudinal direction of the hollow body 14 and can be braced against one another by means of a tensioning element 32, with which an amount defined in the longitudinal direction of the hollow body is adjustable and can be kept largely constant.

The tensioning element 32 is used as a common one Clamping nut 33 arranged on the outside is designed to form tensionable tie rods, the anchor head 34 of which is supported on the back surface 36 of the one wedge plate 31 arranged in the region of the inner, concrete-side end of the hollow body 14, and the clamping nut 33 of which is directed outward via one or more disc springs 37 on the one facing , on the outlet side of the tendons 11-13 or the clamping plates 20-23 from the hollow body 14 arranged back surface 38 of the other wedge plate, optionally with the interposition of support plates 39 and 40 are supported. The shaft 41 of the tie rod 32, which is designed as a round steel rod, runs in a central channel which is formed by longitudinal grooves in the wedge surfaces 43 and 44 of the wedge plates 30 and 31 abutting one another.

The clamping force exerted by the clamping element 32 in the axial direction, the amount of which can be specified very precisely by the prestressing of the plate springs 37, is transformed by the wedge plates 30 and 31 into a transverse pressure of the clamping plate tendon stack, which is uniform over the area of the tendons 11-13 is distributed. A friction-locking anchoring of the clamping members 11-13 between the clamping plates 20-23, and on this anchoring _l to achieve iohlkörper 14, a clamping length of about 25 cm is required, and a transverse pressure of about 30-35N / mm2, a value , which can be achieved with the clamping element 32 and the wedge plate arrangement 30, 31 acting as a force transmission and conversion device without difficulty. In order to protect the tendons made of fiber composite material against possible unraveling under load and transverse pressure, preferably starting from their longitudinal edges, the tendons 11-13 are fitted very precisely into flat longitudinal grooves 46 of the clamping plates 20-23, so that the tendons 11-13 also on most of their narrow longitudinal surfaces from the clamping plates 20-23 are enclosed. 3 shows a modification of the device 10 according to FIG. 1, in that the anchoring body 14 is closed on its inside, where the tendons 11-13 enter, with a welded-on base plate 47, which lies directly against the concrete body 17, on the inside thereof the clamping plates 20-23 are now supported. The tensile load is entered into the concrete body 17 essentially via the base plate 47, in contrast to the device 10 according to FIG. 1, in which the load is essentially supported via the flange 18. In the design of the device according to FIG. 3, it is accordingly not necessary for the clamping plates to be provided with flange pieces 28 on their outside. In the bottom plate 47 provided through openings 48 are expediently designed so that their clear width and height is slightly larger than the width and thickness of the tendons 11-13 so that they can not be damaged when the clamping plate tendon stack is pressed together. The arrangement of the wedge plates 30 and 31 and the tensioning element 32 can be the same as in the device according to FIG. 1, but it is also possible, as indicated by dashed lines, to support the anchor head 34 of the tensioning element on the outside of the base plate 47 facing the concrete. In this case, either a somewhat greater depth must be provided for the recess in the concrete body, or, as also indicated by dashed lines, an additional, small recess 49 receiving the anchor head 34 must be provided for this.

The inner support of the clamping plates 20-23 explained on the basis of FIG. 3 on a base plate 47 of the hollow body 14 is particularly suitable in connection with the end anchoring device 50 shown in FIG. 4 for anchoring tendons 51 and 52 which have a square cross section of approx. 6x6 mm2. The anchoring hollow body 53 is a rectangular hollow profile with 4 vertical profile legs 54 and 56 and horizontal profile legs 57 and 58 are formed. The tendons 51 and 52 are divided into two groups of 12 tendons each, which in the configuration shown in FIG. 4, to whose details are referred to, between horizontal clamping plates 59-62, upright clamping rods 63 and an upright clamping plate 64 as well as the profile leg 54 opposite this and the horizontal profile legs 57 and 58 of the anchoring hollow body 53 are arranged to produce the necessary for the frictionally anchoring the tendons 51 and 52 Clamping forces are provided with two wedge plate arrangements 66 and 67 and clamping elements 68 and 69 which act on them and can be set to a defined prestress, the design and arrangement of which is completely analogous to that of the wedge plate arrangement 30, 31 and the clamping element 32 according to FIGS. 1 and 2. With one, between the inner horizonta Len clamping plates 60 and 61 supported Keilplsttenanordnung 66, a transverse pressure is achieved in the vertical direction, while with the other, between the vertical clamping plate 64 and the right vertical leg 56 according to Fig.4 attacking wedge plate arrangement 67, a transverse pressure of the tendons 51 and 52 in the horizontal Direction is achieved.

The end anchoring device 70 according to the invention shown in FIGS. 5a and 5b is suitable for anchoring tendons 71 with basically any cross-sectional shape, in particular round rod-shaped tendons, which are preferably grouped in the radial-symmetrical distribution shown about the longitudinal axis 72 of the device 70. The device 70 has a circular-cylindrical, pot-shaped anchoring hollow body 74, which is open on the outlet side of the tendons 71 and closed on the inlet side thereof by a base plate 73, and additionally on its outside Lich has a radial annular flange 76 which is supported on the concrete body 17. A tension rod 77 extending along the central axis 72 is provided as the tensioning element, the design of which is completely analogous to that of the tensioning element 32 according to FIG. 1, but its anchor head 78 is on the outside of the Base plate '/ 3
The force transmission device 78 is designed in such a way that it transforms the axially directed clamping force of the tie rod 77 into radially directed transverse forces. In the arrangement and configuration shown in FIGS. 5a and 5b, it comprises an externally circular-cylindrical, internally conical sleeve 79 and one to the inner cone the sleeve 79 is a complementary elongated circular truncated cone-shaped wedge body 80 which has a longitudinal bore 82 through which the shaft 81 of the tie rod 77 passes. The tension nut 83 of the tie rod 78 is supported - again via plate springs 84 - on the larger base surface 86 of the wedge body 80 Tendons are neatly embedded in a clamp body, designated overall by 87, which, viewed in cross-section, preferably completely fills the interior space remaining between the anchoring hollow body 74 and the conical sleeve 79. In order to increase the expandability required for the transverse pressing of the clamp body 87 and the tendons 71 in FIG Rule made of steel g To ensure the finished cone sleeve 79, the jacket is divided into sectors 89 by radial longitudinal slots 88. If the clamping body 87 is made of a very strong material such as steel or aluminum, this must also be divided by longitudinal slots so that a uniform transverse pressure of the tendons 71 This also applies if the clamping body 87 is made of relatively soft lead or aluminum alloys in order to achieve a good conformity of its clamping surfaces to the tendons 71. A suitable arrangement of such slots is shown in broken lines in FIG. 5b , after which the clamping body 87, viewed in cross section, is divided into an outer, coherent ring region 91 and an inner ring region 92 by circular-arcuate slots 90, which run between the longitudinal bores penetrated by the tension members 71, which in turn is divided by radial slots 93 in the individual tension members 71 assigned sectors 94. However, the clamping body 87 can also be made as a one-piece part from a material that is sufficiently deformable in the radial direction, but still has sufficient strength for the force transmission in the longitudinal direction. A suitable material is, for example, filled with mineral fillers and / or epoxy resin reinforced with steel fibers. The clamping body 87 can then be silvered out as a casting body that may not be produced until the device 70 is used, which is only cast when the anchoring hollow body 74 has already been brought into its end position supported on the concrete 17.

If the clamping body is made of the aforementioned, suitably reinforced epoxy resin material or consists of an elastomer, the compressive strength and shear strength of which are increased by suitable reinforcements or fillers while largely maintaining its deformability, the tendons 71 can be anchored instead of an anchoring. 5a, b, the anchoring device 95 shown in FIGS. 6a and 6b can also be used. This differs from the first-mentioned device 70 in design terms only in that instead of the conical sleeve 79 and the wedge body 80, a crimping plate 97 is provided which can be attached to the clamping body 96 from the outside and is displaceably guided on the anchoring hollow body 74 in the axial direction now supports the clamping nut 83 of the tie rod 78 via the diaphragm spring 84 Suitable material selection of squeezable clamping bodies 96 then takes over in connection with the tie rod 77 both the function of converting the axial clamping or squeezing force of the tie rod 77 into the radially acting transverse forces as well as the frictional connection of the tendons 71 with the anchoring hollow body 74, that is, both the function of Power transmission device as well as the function of the clamping device of the aforementioned embodiments.

A major advantage of the quasi-hydrostatic pressure distribution in the Klenun or squeeze body 96 achieved by the squeezing is to be seen in the fact that - in contrast to the device according to FIGS. 5a, b - no forces act on the tendons 71 which lead to a radial Deflection of the tendons 71 could result.

This also applies to the anchoring device 100 according to the invention shown in FIGS. 7a and 7b, whose essential difference compared to that according to FIGS. 6a, b is that a significantly softer material such as polychloroprene or sulfochlorinated polyethylene or the like is used for the squeeze body 99. can be used, which facilitates both the handling of the device 100 and the precise setting of the transverse pressure required for the frictionally anchoring of the tendons 71. In contrast to the device 95 according to FIGS. 6a, b, the movable squeeze plate 101 is at the inner, entry-side end of the arranged circular cylindrical anchoring hollow body 102 and this at its outer end 'closed by a fixed abutment plate 103, on which the clamping nut 83 of the tie rod 77 is supported via the plate spring arrangement 84. Furthermore, the clamping members 71 are inserted in cylindrical clamping sleeves 104 made of steel or aluminum, which are also provided by of the aligned bores lo6 and 107 of the squeeze plate 101 and the abutment plate 103, respectively.

The clamping sleeves have one at their outlet end. radially protruding anchor flange 108, via which the tensile load is entered into the abutment plate 107 and thus into the anchoring body 102. Thus, the clamping sleeves 104, under the "hydrostatic" pressure of the crushed material 99, apply to the tendons 71 with the necessary transverse pressure and the required transverse pressure 7b, they are divided into sectors 110 by radial longitudinal slots 109 in the manner shown in FIG. 7b. However, it is advantageous if the individual sectors 110 are connected at the extreme end 111 of the clamping sleeves 104 via narrow webs, so that from the entry end of the tendons 71 Seen here, where their full tension is effective, the transverse pressure of the tendons increases gradually and only reaches its full value in the interior of the anchoring hollow body 102.

In the end anchoring device 115 shown in FIGS. 8a and 8b, the squeeze body 116 consists of the same material as in the device 100 according to FIGS. 7a, b. Corresponding to the compact arrangement of a large number of a total of 16 tendons 117 within an approximately square cross-sectional area, however, not individual clamping sleeves are provided, but a compact clamping body 118 surrounding the space between the tendons 117 and these on the outside, which can be made of solid steel in the case example shown - Or aluminum block are made, which is first provided with continuous longitudinal bores for receiving the tendons 117, the diameter of which is slightly larger than the diameter of the presupposed tendons as round rods, in order to avoid the already mentioned gentle load achieve at the entry side of the device 115. Then slots 120 and 121 are sawn into this block from its one end face, which intersect at right angles in the axes of the longitudinal bores 119. The depth of the slots 120 and 121 measured in the longitudinal direction of the clamping block 118 is selected to be approximately 1-2 mm less than the length of the clamping block, so that it remains contiguous on its other end face, whereby the attachment of the clamping block 118 to the tendons 117 is made considerably easier. The device 115 has a circular cylindrical anchoring hollow body 122, which is closed on the entry side of the tendons 117 with a base plate 123. The through holes 126 provided on the base plate 123 for the tendons 117 have a somewhat larger diameter than the tendons themselves. The clamping body 118 is inside of the anchoring hollow body 122 so that it is supported with its coherent end on the inside of the base plate 123 in the axial direction. A squeeze plate 124 guided displaceably at the opposite end of the anchoring hollow body 122 has a central recess adapted to the cross section of the clamping body 118 ng 126, through which the clamping body 118 and the free ends of the tendons exit to the outside. It is connected to a radially projecting flange 128 via a short spacer tube section 127, the length of which corresponds approximately to the maximum squeeze path of the squeeze plate 124. A corresponding radially projecting anchor flange 129 is formed at the inlet-side end of the device 115 by the radially projecting edge of the base plate 123. Two tie rods 130 and 131, which engage between the flanges 128 and 129 and are diametrically opposed to one another outside the anchoring hollow body 122, convey the defined adjustable preload with which the squeeze body 118 in Axial direction is compressed so that the transverse pressure required for the frictional anchoring of the tendons 117 is achieved in the coupling body 118.

As already explained in connection with the device 95 according to FIG. 6a, a suitably reinforced cast body made of metal fiber reinforced epoxy resin or the like can also be used in the device 115 according to FIG is then cast "on site" with the squeeze plate 124 removed, which for this purpose is pushed back somewhat along the tendons 117 in the direction of the drawing head, not shown, which still acts on the tendons 117.

If prefabricated clamping or squeezing bodies are used in connection with the anchoring devices explained in accordance with FIGS. 1-8b, they can be installed in the respectively shown assembly state, in which they are pushed onto the tendons before tensioning, after tensioning the tendons in their final position are pushed into the concrete recesses that receive them, where their tensioning elements are then tensioned.

Further measures or designs of such devices which are advantageous in connection with various of the illustrated embodiments are the following:

In cases in which squeeze bodies made of plychloroprene or similar, relatively soft materials are used, it is advantageous if steel balls are poured into this squeeze body in a tight ball packing, i.e. an arrangement in which a squeeze of the ball cluster embedded in plastic in this way is in itself alone to one In this way, aging effects or temperature influences, which would lead to changes in the transverse pressures generated by the crimping bodies, can be effectively eliminated from the outset. It is furthermore expedient if tendons which have a roughly structured surface roughness and in clamping sleeves or clamping bodies made of very strong material, are provided with a cladding 135 made of a resilient material such as lead or aluminum, which, due to plastic deformation under the applied transverse pressure, enables a uniform filling between the tendons and the gaps of existing gaps.

If, on the other hand, the abutting surfaces of both the tendons and the clamping sleeves or bodies are very smooth and their shape is well matched to one another, it can be advantageous if a sheet of paper or plastic coated with fine-grained corundum split is arranged between these surfaces If the clamping is sufficiently strong, the corundum grains can penetrate the film and penetrate both into the tendons and into the clamping sleeves or clamping bodies surrounding them, which increases the friction between these bodies and achieves better anchoring of the tendons with the specified transverse pressure can.

The device 210 according to the invention shown in FIG. 9, to the details of which reference is expressly made, comprises an externally cylindrical, internally conical anchoring hollow body 213, which is accommodated over a large part of its length by a cylindrical recess 214 in the prestressed concrete component 212 and engages with one at its according to Fig. 9 ring flange 216 arranged on the left end is supported on the outer surface 217 of the prestressed concrete component 212. The tendons 211, for example round GV rods with a diameter of approx. 8 mm, which penetrate the anchoring hollow body 213 in its longitudinal direction, are preferably in a radial-symmetrical grouping about its longitudinal axis 218 arranged at a distance from each other and can be prestressed to the required longitudinal tensile stress by means of a conventional tensioning press, not shown. At its right-hand end according to FIG. 9, at which the tensioning members 211 enter the anchoring hollow body 213, this is with a solid base plate 219 completed, which is provided with passage openings 220 for the tendons 211.

In the interior of the anchoring hollow body 213, which tapers conically from the exit side to the entry side of the tendons 211, the tendons 211 are embedded over the majority of their length in a truncated cone-shaped clamping body 221, which is displaced in the direction of the direction of engagement of the tendons attacking longitudinal tensile forces marked arrow 222 experiences a transverse pressure acting on the tendons 211, the amount of which is proportional to the displacement.

Between the base plate 219 of the anchoring hollow body 213 and the entry-side, smaller end face 223 of the clamping body 221 there is a buffer layer 224 which fills the remaining cavity in the anchoring hollow body 213 and is made of a compressible material such as PVC (polyvinyl chloride) or PS (polystyrene) rigid foam intended.

For the purpose of further explanation, it is assumed without restriction of generality that the clamping body 221 as a casting body is formed, which consists of a mineral filler and / or reinforced with steel fibers epoxy resin. The device 210 described so far can then be used to achieve a stable end anchorage of the GM tendons as follows:

After the anchoring hollow body 213 has been brought into the position shown in FIG. 9 and the required prestress has been impressed on the tendons 211 by means of a tensioning press, not shown, the clamping body 221 is cast, the plate-shaped buffer layer 224 made of rigid foam initially acting as "lost formwork", which is not yet compressed, at least not significantly, under the hydrostatic pressure of the potting compound. During the casting of the clamping body 221, the prestressing exerted on the tendons 211 by means of the clamping press is maintained. As soon as the potting clamping body 221 has hardened, that is hardened by means of the The tension force generated, preferably steadily or in small steps, may be immediately reduced by the full amount. Under the increasing tension on the clamping body of the tendons 211, the clamping body 221 adhering to the clamping body in the direction of arrow 222 is now more and more 'in the anchoring hoop Cooling element 213 is drawn in until the buffer layer 224 supported on the outside on the base plate 219 acting as a stop plate is compressed to such an extent that it in turn acts as a "hard" stop plate and prevents further displacement of the clamping body in the axial direction The course of the displacement of the constantly increasing and transmitted to the tendons 211 transverse pressure of the clamping body 221 reached, the final amount can be specified by a suitable choice of the initial thickness of the buffer layer 224 such that the transverse pressure required for frictionally anchoring the tendons of the clamping body 221 and the tendons 211 itself achieved with certainty, a transverse pressure of the tendons 211 going beyond a safety margin, which would reduce their breaking strength, but is reliably avoided.

As soon as the clamping body 221 has reached the end position shown in dashed lines in FIG. 9 and thus there is no significant displacement of the tendons 211 relative to the prestressed concrete body 212, the prestressing channel 226 and, if appropriate, the recess 214 of the prestressed concrete component 212 receiving the anchoring hollow body 213 can be suitably Potting compound be squeezed out.

Also in the preferred embodiment of an end anchoring device 230 according to the invention for a number of GV tendons 231 shown in FIG. 10, the details of which are expressly referred to again, a gentle anchoring thereof is achieved by limiting the displacement of its clamping body 232 relative to the anchoring hollow body 233 reached.

With regard to the arrangement of the GV tendons 231, the internally conical design of the anchoring hollow body 233, its arrangement in a recess 214 of the prestressed concrete component 212 and its support on its outer surface 217 via an annular flange 216, and with regard to the design of its clamping body 232 as a casting cone with the conical The internal shape of the anchoring hollow body 233 of a complementary truncated cone shape allows the device 230 to be designed completely analogously to the device 210 according to FIG.

As can be seen from FIG. 10, the small body 233 is arranged between an abutment plate 234 on the inlet side and an abutment plate 236 on the outlet side can be connected to one another in a tension-resistant manner by a tie rod 237, which is supported with its head 238 on the outside of the abutment plate 234 and with its clamping nut 239 directly or indirectly on the outside of the stop plate 236. According to FIG. 9, the clamping body 232 along the central longitudinal axis 240 The tie rod 237 passing through the device 230 is dimensioned such that it can withstand the full longitudinal tensile force introduced into the device 230. It should expediently be made of high-strength steel, for example of the grade 8.8.

The abutment plate 234 and the stop plate 236 are provided with aligned openings 241 and 242 for the GV tendons 231, the inside width of which is slightly larger than the diameter of the tendons 231. The diameter of the abutment plate 234 is slightly smaller than the smallest inside diameter of the anchoring hollow body 233 on that section of its length within which the abutment plate 234 must be displaceable. The diameter of the stop plate 236, the maximum axial distance of which from the abutment plate 234 or the exit-side end face 243 of the anchoring hollow body 233 can be adjusted by means of the clamping nut 239, is clear larger than the inner diameter of the anchoring hollow body 233 at its outlet end, so that it limits the retraction movement of the clamping body 232 by its abutment on the end face 243 of the anchoring hollow body 233.

The device 230 described so far can be used as follows to achieve a stable end anchorage of the GM tendons 231:

After the anchoring hollow body 233 is brought into the position shown in FIG. 10 and the tendons by means of 10, the abutment plate 234 is brought into the position shown in dashed lines according to FIG. 10 and is adequately fixed in this position by means of the tie rod 237. Then the clamping body 232 is produced, preferably the whole between the abutment plate 234 and existing cavity is poured out at the outlet end of the anchoring hollow body 233.

A flat-plate-shaped sealing body 246 provided between the abutment plate 234 and the clamping body prevents the casting compound from escaping through the edge gaps between the anchoring hollow body 233 and the abutment plate 234 or between the latter and the tensioning members 231. After the clamping body 232 has hardened, Already described in connection with the device 210 according to FIG. 9, the retraction-displacement movement of the clamping body 232 is initiated by lowering the tensile force generated by means of the tensioning press can be specified in various ways with the device 230:

On the one hand by specifying the effective length of the tie rod 237, the maximum distance which the stop plate 236 can take from the end face 243 is determined by suitable adjustment of the clamping nut 239, and on the other hand by monitoring the preload force, which is reduced continuously or stepwise by means of the press press Locking of the stop plate 236 at a predetermined pressing force. In both cases, the tendons 231 must first be spanned by a predetermined amount by which the displacement Movement of the clamping body 232 to compensate for relaxation.

As indicated in FIG. 10 by a plate spring arrangement 247, the clamping nut 239 can be supported on the stop plate 236 via a spring-elastic element, which is designed in such a way that a restoring force at about half or even a smaller fraction of its maximum spring travel is to be accommodated Tensile force corresponds.

Through this resilient member 247 a displacement "reserve" is achieved, which comes into play when the clamping body 232 experiences a volume loss due to a time-delayed shrinkage process or the like, which, if the connection between the abutment plate 234 and the stop plate 236 rigid would lead to a decrease in the transverse pressure of the clamping body 232 and thus to a reduction in the frictional fixation of the tendons 231.

It is understood that in the case of resilient support of the tie rod 237 on the stop plate 236, the recess 214 of the prestressed concrete component 212 receiving the anchoring hollow body 233 must not be fully pressed with a casting compound in the area adjacent to the abutment plate 234. In order to prevent this, the anchoring hollow body 233 is to be closed at its entry-side end with a base plate 249 provided with narrow through openings 248 for the GM tendons 231 or, for example, to be sealed with a foam layer.

Furthermore, it goes without saying that, in the context of a device according to the invention, instead of clamping bodies designed as potting bodies, clamping bodies made of other materials and slotted in the longitudinal direction can also be used, which, if necessary, the GV tendons only on sector areas of their circumference enclose, and that instead of a single central tie rod, a plurality of tie rods, which may also extend outside the anchoring hollow body, can be provided.

It may also be expedient not to support the anchoring hollow body directly on the prestressed concrete component on the entry side of the tendons, e.g. on a base plate, rather than on an external ring flange.

The end anchoring device 310 according to the invention shown in FIGS. 11 and 12, to the details of which express reference is made, comprises a conical, pot-shaped anchoring hollow body 313, which is accommodated over a large part of its length by a likewise conical recess 314 in the prestressed concrete component 312 and engages with one on it According to the left end of FIG. 12, the annular flange 316 is supported on the outer surface 317 of the prestressed concrete component 312.

The anchoring hollow body 313 is preferably made of steel, and an intermediate space between the anchoring hollow body 313 and the somewhat further recess 314 is filled with grout in the fully assembled state of the device 310. However, the anchoring hollow body 313 can also be an injection-molded plastic part, for example made of polyamide or Polystyrene hard can be formed, which is also used as formwork for the recess 314 of the prestressed concrete component 312.

The tendons 311, for example round glass fiber composite rods with a diameter of approx. 8 mm, which penetrate the anchoring hollow body 313 in its longitudinal direction, are arranged in a preferably radially symmetrical grouping around its longitudinal axis 318 and can not be shown by means of one provided usual tensioning press to be pretensioned to the required longitudinal tension.

At its right end according to FIG. 12, at which the tendons 311 enter the anchoring hollow body 313, the latter is closed with a solid base plate 319, which is provided with through openings 320 for the tendons 311 and clamping sleeves 321 enclosing them Exit side to the entry side of the tendons 311 tapering interior of the anchoring hollow body 313, the tendons 311 or the clamping sleeves 321 are embedded over the major part of their length in a truncated cone-shaped clamping body 322, which is displaced in the direction of the direction of attack of the tendons The arrow 323 acting on the longitudinal tensile forces 311 experiences a transverse pressure which is transmitted via the clamping sleeves 321 to the tendons 311 and the amount of which is proportional to the displacement of the clamping body 322. The clamping body 322 is manufactured from an epoxy resin base or from another suitable one Existing material Casting body formed, which rests under pressure on the entire anchoring length under pressure on the conical inner wall 324 of the anchoring hollow body 313 by axial crushing.

The outlet-side, wide opening of the anchoring hollow body 313 is covered except for a narrow edge gap 326 with a solid pressure plate 328 which bears against the outlet-side base surface 327 of the clamping body 322 and which has narrow passage openings 329 for the tendons surrounding the through-openings 320 of the base plate 319 Is provided clamping sleeves 321, which are supported with radially projecting flange pieces 331 on the outer surface 332 of the pressure plate 328.

In the exemplary embodiment shown, the clamping sleeves 321 are designed as steel or aluminum tubes with a wall thickness of about 2-4 mm. The jacket 333 of these clamping sleeves is in turn formed by radial longitudinal slots 334, which extend from the outlet-side end face at least until approximately the start of the base plate 319 extending end portion 336, divided into sectors that are connected to the tubular end portion 336, which has a length of about 2 cm.

Provided between the base plate 319 of the anchoring hollow body 313 and the entry-side, smaller base surface 337 of the clamping body 322 is a buffer layer 338 which fills the remaining cavity in the anchoring hollow body 313 and is made of a compressible material such as PVC (polyvinyl chloride) or PS (polystyrene) rigid foam.

The device 310 described so far can be used as follows to achieve a stable end anchoring of the GM tendons:

After the anchoring hollow body 313 has been brought into the position shown in FIG. 11 and the prestressing means 311 have been subjected to the required prestressing by means of a prestressing press (not shown), the clamping body 322 is cast, the plate-shaped buffer layer 338 initially acting as "lost formwork", which is under the hydrostatic pressure of the potting compound is not yet compressed, at least not appreciably. During the casting of the clamping body 322, the prestressing exerted on the tendons 311 by means of the clamping press is maintained. As soon as the potting clamping body 322 has hardened, the tensile force generated by the clamping press becomes preferably continuously or in small steps, if necessary, also immediately withdrawn by the full amount. Under the prestressing of the tendons 311, which increasingly acts on the clamping body 322, the clamping body 322 is pressed increasingly in the direction of the arrow 323 into the anchoring hollow body 313 until the buffer layer 338 is compressed so far that it because of its support on the base plate 319 acts as a "hard" stop plate and prevents further displacement of the clamping body in the axial direction. This in turn results in a limitation of the continuously increasing transverse pressure of the clamping elements 321 transmitted to the tendons 311 via the clamping sleeves 321 312 over the clamping members 311 total effective tensile force at a load of prestressed concrete part is kann.Erhöht be clamp body 322 reaches whose for a secure anchoring of the clamping members 311 required _M domestic least amount by appropriate choice of the initial thickness of the buffer layer 338 specified, the Auss because of the Supporting the clamping sleeves 321 on the pressure plate 328 via this is inserted into the clamping body 322, this undergoes, depending on the mechanical properties of the material selected for the clamping body 322, a more or less severe crushing, with which an increase in the transverse pressure in the clamping body 322 is connected, which is distributed very well evenly over the anchoring length of the tendons 311 in the structure shown in FIG.

In the illustrated embodiment according to FIGS. 13 and 14, to the details of which reference is expressly made, the tendons 411 and 412 are in turn formed as approximately 8 mm thick round bars which, with a horizontal or parallel arrangement, are symmetrical with respect to the horizontal longitudinal center plane 414 of the device 410 as a whole five parallel rows of seven tendons 411 and 412 each next to each other or are arranged one above the other, in the central row for a reason to be explained below, in addition to tendons 412 and also blind rods with the tendons 412 of corresponding nature are provided.

The central component of the device 41o, which is generally symmetrical with respect to the horizontal longitudinal center plane 414 as well as with respect to its vertical longitudinal center plane 416, is a stacking arrangement comprising clamping plates 418-425 and flat wedges 426 to 429, shown in FIG 430 designated clamping body is provided, which is received in its position of use shown in Fig. 13 over the major part of its length by a recess 431 of the prestressed concrete component 413 or by an anchoring hollow body 432 inserted therein, and, standing under a sufficient transverse pressure, the frictional anchoring the tendons 411 and 412 mediate.

The clamping body elements 418-429 are expediently placed in their stacked arrangement on the tendons 411 and 412 and, after the tendons, the necessary before the tendons 411 and 412 are brought to the required tension by means of a tensioning press, not shown Tension-preload is impressed, pushed from the outlet side of the tendons into the end position shown in the recess 431 or the anchoring hollow body 432. The clamping plates 418-425, between which the four outer rows of tendons 411 are held and which close The flat wedges 426 and 429 which, according to FIG. 13, emerge on the left-hand side of the tendons 411 and 412 and which taper towards the central flat wedges 427 and 428, between which the middle row of tendons 412 is held, have on their outside the recess 431 arranged end sections laterally projecting flange pieces 433, via which the tendon forces are introduced into an abutment plate 436, which bears against the outer surface 434 of the prestressed concrete component 413 and surrounds the opening of the recess 431, or through which a further axial displacement of these clamping body elements 418-426 and 425-429 Entry side of the tendons 411 and 412, ie towards the concrete part 413, is prevented.

The central flat wedges 427 and 428, between which the tendons 412 of the central row are enclosed, form an axially displaceable wedge body, the wedge angle of which corresponds to the opening angle of the V-shaped gap, which widens towards the exit side of the tendons 412 the inner wedge surfaces 437 and 438 of the outer flat wedges 426 and 429 is limited.

By driving this wedge body 427, 428 into the V-gap 437, 438, the clamping body elements 418-429 and which are supported perpendicularly between the mutually opposite walls 439 and 441 of the recess 431 and the anchoring hollow body 432 with respect to the axes of the tensioning members 411 and 412 compress the tendons 411 and 412 arranged between them until the minimum transverse pressure of these parts 411 and 412 or 418-429 required for anchoring the tendons 411 and 412 securely under service load is reached, after which the tensioning press with which the tendons 411 and 412 were previously kept at the required tension, from which they can be disconnected.

The device 410 explained so far has the following functional properties:

Of the train occurring when the concrete component 413 is loaded Forces that are introduced into the anchoring device 410 via the tendons 411 and 412, an increase in the transverse pressure of the tendons results only from the load-dependent tensile force component that acts on the central tendons 412. With identical design of the tendons 411 and 412 and uniform transverse pressure of the The tendons in the clamping body 430 thus the proportion of the tensile force which is decisive for the increase in the transverse pressure to the tensile force to be absorbed by the anchoring device as a whole relates to the number of central tendons 411 to the total number of tendons 411 and 412. with which an increase in the tensile forces acting on the tendons 411 and 412 causes an increase in the transverse pressure of the tendons 411 and 412, is defined in a defined manner and is kept at a value that is suitable for the long-term load capacity of the tendons 411 and 412 In the specific exemplary embodiment shown, the value of this conversion ratio, if all of the bars arranged between the flat wedges 427 and 428 were to act as tendons 412, would only be 1/5 of the value that is known in the case of known wedge or potting anchors, in which all of the stretches are introduced into the anchoring device Tractive forces make their contribution to the transverse pressure of the tendons, but must be accepted. However, in order to achieve a further reduction in the transverse pressure or transverse force / tensile force ratio required for the wedge angles shown in practice, some of the rods held between the central flat wedges 427 and 428 are For example, the four bars marked by a hatched hatch in FIG. 14 are designed as blind bars and only three bars that act as tendons 412 are provided, whereby the numerical ratio mentioned is reduced to less than 1/10.

In the illustrated embodiment, the clamping body elements 418-429 are preferably made of steel; however, they can also be made of another material that has a strength that is sufficiently high for power transmission in the longitudinal direction. The clamping plates 418-425 and the central flat wedges 427 and 428 are on their sides facing the tendons 411 and 412, respectively, with receiving grooves 442 and 443 for the tendons 411 and 412, which are neatly embedded in these grooves 442 and 443 and are enclosed on most of their circumference by the groove walls, so that between the The tendons 411 and 412 facing sides of the clamping plates 418-421 and 422-425 and the central flat wedges 427 and 428 only have narrow, approx. Now wide edge gaps 444 and 446.

In the illustrated embodiment according to FIGS. 13 and 14, the clamping body 430 overall has an approximately cuboid basic shape with plane-parallel outer surfaces 447 and 448 of the outermost clamping plates 418 and 425, respectively, with which the clamping body 430 is located on the mutually opposite inner walls of the recess 431 It is understood that these inner walls 439 and 441 must also run parallel to one another as well as possible, so that a uniform distribution of the transverse pressure of the tendons 411 and 412 over the anchoring length of the tendons is ensured. if the clamping body 430, as shown in the lower part of FIG. 13, can be inserted into an anchoring hollow body 432, which in turn is inserted into a correspondingly further recess in the concrete component 413, because with such a part, such as a prefabricated steel hollow profile body, the plane parallelism t of the support surfaces 439 and The clear internal dimensions of the anchoring hollow body required for the anchoring position of the clamping body 430 shown can be easily achieved in terms of production technology. No special requirements then have to be made of the clear internal dimensions of the recess 431 into which the anchoring hollow body 432 is inserted, since a between the anchoring hollow body 432 and the longitudinal walls of the recess 431 remaining cavity, into which the tension channel 449 opens at the entry side of the tendons 411 and 412, can be pressed into its position of use after the attachment of the anchoring device 410, so that the device 410 is then securely held in its desired position , even if the longitudinal walls of the recess 431 of the concrete component do not run exactly parallel to one another and / or have considerable surface roughness.

However, if, as shown in the upper part of FIG. 13, the concrete component 413 with its recess 431 itself is to be used as an "anchoring hollow body" for the clamping body 430, then it is advantageous if between at least one of the outer clamping plates 418 and 425 and an approximately 2-4 mm thick compensation layer 450 made of a resilient material, e.g. neoprene, is provided for this opposite support surface 439, so that the parallel position of the clamping plates 418-425 required for an even distribution of the transverse pressure over the anchoring length of the tendons 411 and 412 is automatic and the central flat wedges 427 and 428 can adjust, even if the Ab-. Support surfaces 439 of the concrete component are not exactly flat or do not run exactly parallel to one another. A compensation layer 451 which is equivalent in function to this compensation layer 450 can alternatively also be located between adjacent surfaces of the Clamping plates 419 and 420 or 423 and 424 or, as indicated by dashed lines in FIG. 13, can be provided between one of the inner clamping plates 421 or 422 and the adjacent flat wedge 426 or 429, which delimits the V-shaped gap on one side, in where the central flat wedges 427 and 428 are inserted.

Since production-related surface roughness of the composite material tendons 411 and 412, when they are pressed together between smooth clamping body parts, could locally lead to tip transverse pressures which go beyond the permissible extent, it is advantageous, as shown in FIG. 15, if the tendons 411 and 412 are embedded in a somewhat flexible adhesive layer 452 or 453, which, to compensate for unevenness in the clamping body elements and the tendons, clings to the surface and thus provides a uniform distribution of the transverse pressure over the anchoring length. The material for such an adhesive layer is a plastically deformable material or an elastomer reinforced with metal or glass fiber or with ceramic fillers. The adhesive layer 452 or 453 can either, as shown in the lower part of Fig .1-2mm thick coating of the tendons 411, or, as shown in connection with the central flat wedges 427 and 428 and the clamping plates 418-421 arranged above, be formed as a coating of these clamping body elements, in which case the adhesive layers 453 or 454 each form half shells that enclose the tendons 412 and 411. These coatings 453 and 454 of the clamping body elements can either be designed as relatively thin-walled layers 454 following the contour of receiving grooves 442, or as a comparatively solid layer, possibly sunk in the clamping body elements arranged plates 453, the thickness of which is at least about 1 mm larger than half Diameter of Tendons 411 or 412, which then dig into these adhesive layers when the clamping body 430 is pressed together. It is advantageous if the surfaces of the clamping body elements 418-425 or 427 and 428 adjacent to the adhesive layers 452-454 are roughened to a defined extent, whereby with a given transverse pressure an improved adhesion of the tendons 411 and 412 and the clamping body 430 can be achieved and, as a result, a reduction in the minimum transverse pressure required for their frictional anchoring, which is beneficial for the protection of the tendons 411 and 412, can be achieved Adhesive layers 452-454 also convey the function of the compensation layers 450 and 451.

Also in the design of an end anchoring device 460 according to the invention shown in FIG. 16, the desired limitation of the increase in the transverse pressure of tendons 411 and 412 as a function of tensile forces acting on them is determined by a suitable choice of the numerical ratio of tendons 412, which is frictionally attached to a wedge body clamp body part 461 which can be displaced in the axial direction of the device 460 are achieved to tension members 411 which are held in a frictionally locking manner on a clamp body part 462 which is supported against displacement in the axial direction, so that the device 460 according to FIG. 16 to the device 410 according to FIGS. 15 is completely analogous in this respect. Accordingly, elements of device 410 according to FIGS. 13-15 have functionally identical or analogous functional elements of device 460 according to FIG. 16 with the same reference numerals, and in the following, in order to avoid repetitions, it is essentially only intended to be repeated on d The structural differences of the device 460 compared to the device 410 are discussed.

The device 460 comprises an externally cylindrical, internally conical anchoring hollow body 463, which is received over most of its length by the likewise cylindrical recess 43 of the prestressed concrete component 413 and with an annular flange 464 arranged on its left end according to FIG. 16 on the outer surface 434 The tendons 411 and 412 passing through the anchoring hollow body 463 in the longitudinal direction are in turn arranged in a preferably radially symmetrical grouping around the longitudinal axis 466 of the device 460. At its right-hand end according to FIG. 16, at which the tendons 411 and 412 in When the anchoring hollow body 463 enters, it is closed off with a solid base plate 467, which is provided with through openings 468 for the tendons 411 and 412. Both the wedge body 468, which has the shape of an externally conical, internally circular cylindrical sleeve, as well as that central circular cylindrical sprag part 462 can be used as a Casting parts manufactured in the place of use are formed, which are separated from one another by an approximately 0.5-1 mm thick sliding jacket 469 which is used as "lost formwork" and is preferably made of steel, aluminum or plastic. This sliding jacket 469 is expediently provided by narrow longitudinal slots in jacket sectors subdivided so that it, as far as possible, quantitatively resulting from an axial displacement of the wedge body 461 in the direction of the arrow 470, which impart the transverse pressure required for the frictional anchoring of the tendons 411 and 412 thereof or of the clamping body 430 comprising the wedge body 461 and the partial body 462 transmits.

Between the bottom plate 467 of the anchoring hollow body 463 and the entry-side smaller end face 471 of the wedge body 461 is one when the wedge body 461 is created also used as "lost formwork" buffer layer 472 made of a compressible material such as PVC (polyvinyl chloride) or PS (polystyrene) rigid foam material, which ensures the axial displaceability of the wedge body. This buffer layer 472 can optionally be designed such that it opposes an axial displacement of the wedge body 461 in the direction of the arrow 470 and can thus also counteract an increased transverse pressure of the clamping body 430 or the tendons 411 and 412.

The device 510 according to the invention, shown in FIG. 17, to the details of which is expressly referred to, comprises a cylindrical-pot-shaped anchoring hollow body 513, which is received over the majority of its length by a likewise pot-shaped-cylindrical recess 514 of the prestressed concrete component 512 in FIG whose central floor area opens out through the tendons 511 through the tendons 516 of the prestressed concrete component 512. The anchoring hollow body 513 passed through in the longitudinal direction by the tendons 511 and these clamping sleeves 517 is at its inner end facing the prestressing channel 516, where the tendons 511 in the anchoring device 510 enters, with a bottom plate 519 provided with through openings 518 for the tendons 511 or these enclosing clamping sleeves 517. At its outer end, at which the tendons 511 emerge from the device 510, the anchoring hollow body 513 is with one protrude radially the ring flange 521, with which it is supported on the outer mandrel section 522 of the prestressed concrete component 512 that delimits the outlet-side opening of the recess 514. The outlet-side opening of the anchoring hollow body 513 is, apart from a narrow edge gap 523, from a parallel to the base plate 519, in the longitudinal direction Direction of the tendons 511 slidably at the outer end of the cylindrical shell 524 of the anchoring hollow body 513 supported crush plate 526, which in turn is provided with the through openings 518 of the bottom plate 519 aligned through openings 527 for the clamping sleeves 511 enclosing the tendons 511. The essentially elongated-tubular Clamping sleeves 517 are. provided at its outlet end with flange pieces 528 projecting radially from the sleeve casing, with which they are supported in the illustrated position of use of the device 510 on the outer surface 529 of the squeeze plate 526. In the remaining between the squeeze plate 526 and the base plate 519, from the cylindrical jacket 524 of the Anchoring hollow body 513 is a hollow space 530 made of a material expandable by squeezing such as polychloroprene, sulfochlorinated polyethylene or the like, which displaces the squeeze plate 526 towards the base plate 519 towards axial tensile or prestressing forces in the interior of the anchoring hollow body 5 the proportional "hydrostatic" pressure and thus also into transverse forces directed transversely to the clamping sleeves 517 and tendons 511, which, with sufficient squeezing of the squeezing body 530, is sufficient for the frictional fixing of the tendons 511 Provide transverse pressure of the clamping sleeves 517. In order to set a sufficient transverse pressing of the crimping body 530 or the clamping sleeves 517 and the tendons 511 without additional device (clamping press) for a given service load. 17, a pretensioning device 531 which can be actuated from the outside of the device 510 is provided. This is shown in FIG. 17 by a single one, which extends along the central longitudinal axis 532 of the device 517 and is supported on the outside of the squeeze plate 526 Tension nut 533 represents tensionable tie anchors, the head of which is 534 the opposite outer side 536 of the base plate 519, and the shaft 537 of which passes through mutually aligned bores 538 and 539 of the base plate 519 and the squeeze plate 526, respectively.

The device 510 described so far is as follows; settable:

First of all, the end anchoring device 510 comprising the anchoring hollow body, the crimping body 530, the squeezing plate 529, the clamping sleeves 517 and the tensioning device 531 is attached to the tendons 511, which are preferably arranged radially symmetrically about the central longitudinal axis 532, and if necessary from the start into the illustrated end position of their anchoring hollow body 513 Recess 514. Then the prestressing provided for the prestressing of the concrete component 512 can be impressed on the prestressing members 511 by means of a conventional prestressing press, not shown. Then, after the prestressing device 531 has been actuated, the prestressing press is decoupled, so that the resulting equilibrium position over the squeeze plate 526 the transverse compression of the clamping sleeves 517 and the tendons themselves, which is required for the secure anchoring of the tendons 511, is then achieved. After that, if necessary, even before the tensioning device 531 is actuated, the cavity remaining between the anchoring hollow body 513 and the recess 514 of the prestressed concrete component 512 and that of the tendons enclosing clamping channel 516 with grout or some other suitable mass. In the event of a load, increased tensile forces that are entered into the anchoring device 510 via the clamping sleeves 517 and the squeeze plate 526 lead e.g. u an increase in the transverse pressure, during which the tensile

Force-unit-related increase is determined by the dimensions of the Quetch body and its mechanical properties and can be varied within wide limits by appropriate design specifications of these parameters and thus can also be adjusted to the value most favorable for the respective use case. The embodiment shown in FIG -. Device 540 according to the invention is completely analogous to the device 510 shown in FIG. 17 with regard to its intended use - end anchoring of tendons 511 - and with regard to the principle used to restrict the load / transverse compression ratio. Accordingly, elements of device 510 according to FIG. Analog elements of the device 540 according to FIG. 18 are given the same reference numerals.

The device 540 according to FIG. 18 is particularly suitable for the end anchoring of a bundle of tendons 511, which are grouped in a narrow, preferably axially symmetrical distribution about the central axis 541 of the device 540. They are inserted in an overall block-shaped clamping sleeve body 542 made of steel or aluminum is provided with longitudinal slots which ensure the flexibility in the transverse direction required for the transmission of the transverse pressure to the tendons 511. The slots which are preferably sawn in from the exit-side end face 544 of the clamping sleeve body 543 end in the illustrated embodiment at a distance of a few millimeters from the exit-side end face 546 of the clamping sleeve body, so that the parts of the clamping sleeve body 542 which only abut on sector regions of the tendon lateral surfaces are connected on the entry side of the tendons 511, which can be particularly advantageous for the assembly of the device 540 In accordance with the compact design of the clamping sleeve body 542, the base plate 519 and the squeeze plate 526 each have only one central passage opening 547 550 for the Klermahülsenenkör- 542, which in turn is supported via peripheral radial flange pieces 528 on the outside 529 of the squeeze plate 526. The preferably radially symmetrical with respect to the central axis 541 anchoring hollow body 513 has in an outer cylindrical part 547, in which the squeeze plate 526 is arranged displaceably, a significantly larger diameter than in its inner cylindrical part 548, which is closed off by the base plate 547. Between an annular flange-shaped base plate of the outer cylindrical part 547, which runs parallel to the squeeze plate 526, and the jacket of the inner cylindrical part 548 of the anchoring hollow body 513 in the arrangement shown in FIG. 18, a funnel-shaped intermediate piece 551, the conical inner surface 552 of which, each with a smooth curvature, fits onto the inner surface of the ring flange-shaped base plate 549 or the inner lateral surface 554 of the inner anchoring hollow body section 548 The dimensions of the anchoring hollow body 513 and the clamping sleeve body 542 are selected such that the partial volumes of the squeezing body 530 which are closed in the narrower part 548 and in the further part 547 of the anchoring hollow body 513 are approximately the same size and that between the squeezing plate 526 and the annular bottom flange plate 549 measured depth of the enlarged part 547 is approximately 1/10 to 1/5 of the total length of the device 540. The handling and function of the device 540 are analogous to those according to FIG. 517, with the setting of a minimum transverse compression of the tendons 511; and the clamping sleeve body 542 can be used in the manner shown in FIG. 18 and provided in the extended part 547 of the anchoring hollow body 513 tension anchor 556.

For the assembly of the device 540, it is useful if the clamping sleeve body 542 has a conical outer shape which tapers slightly towards the entry side of the tendons 511, in order to be easier to insert into the squeeze body 530, which is preferably designed as a prefabricated part. If necessary, the squeeze body 530 can also, as indicated by dashed lines, one of the partial layers 557-560 comprehensive layer structure, these sub-layers 557 to 560 have different deformation properties, for example graded degrees of hardness, by their suitable choice a certain transverse compression behavior of the squeeze body 530 can be achieved over the anchoring length of the tendons 511, it being expedient if the hardness of the sub-layers 557 to 560 decreases from the entry side of the tendons 511 to the exit side.

The characteristic advantage of the device 540 according to FIG. 18 is that, with an overall slim and space-saving construction, there is nevertheless a large contact surface of the squeeze plate 526 with the squeeze body 530, with which low values of the conversion ratio can be achieved, with which the tendons can be used attacking tensile forces are converted into proportional transverse pressures.

Claims (45)

1.Device for end anchoring, at least as a tendon in prestressed concrete construction, rod made of fiber composite material, with an anchoring hollow body which can be fixed on the prestressed concrete component and in which a clamping element extending through a length section is arranged and penetrated by the rod, on which by means of a clamping device transverse forces acting at right angles to the longitudinal axis of the rod and imparting a frictional connection between the rod and the clamping body or the anchoring hollow body can be exerted, the clamping body being part of a longitudinal force / transverse force conversion device with which forces introduced into the device in the longitudinal direction of the rod are proportional thereto the transverse forces imparting the frictional connection between the rod and the clamping body can be transformed.
characterized in that the longitudinal / lateral force conversion device comprises a lateral force limiting device with which a predeterminable amount of the lateral forces can be set. 2. Device according to claim 1,
characterized in that at least one limit value element (37; 84; 224; 247; 338; 472;) is provided in the context of the force conversion or limiting device, by means of which an upper limit of the transverse force can be predetermined. 3. Device according to claim 2,
characterized in that the force conversion device (30.31; 66.67; 79.80; 96.97; 99.101; 116.124) acts as a limit element from the rod exit side of the anchoring hollow body (16; 53; 74; 102; 122) of actuatable clamping element (32; 77; 130; 131), with which a defined amount parallel to the longitudinal direction of the tendon (11-13; 51,52; 71; 117) or of the anchoring hollow body can be adjusted, from the implementation of which the the frictional fixation of the tendon mediating transverse forces result. 4. The device according to claim 3,
characterized in that the force conversion device, which transforms the axial clamping force generated by the clamping element (32) into a transverse pressure to be transmitted to the clamping element (11-13), has at least one pair of wedge plates (30, 31), the wedge plates of which by means of the Clamping element (32) can be clamped against each other (Fig.1). 5. The device according to claim 4,
characterized in that the abutting wedge surfaces (43, 44) of the wedge plates (30, 31) are provided with mutually opposite groove-shaped recesses which delimit a channel running in the longitudinal direction of the device (10), in which the shaft (41) of a tie rod runs, which is supported with its anchor head (34) on the back surface (36) of the one wedge plate (31) and can be tensioned by means of a tension nut (33) which is located on the back surface (38) via the spring-elastic tensioning element, e.g. a disc spring arrangement (37) ) supports the other wedge plate (30) (Fig.1). 6. The device according to claim 3, 4 or 5 for at least one flat bar-shaped tendon,
characterized in that the tendon (11-13) is arranged between clamping plates (20-23) which have flat longitudinal grooves (46) whose inside width corresponds to the width of the tendon (11-13), the sum of the groove depths being somewhat smaller is than the thickness of the tendon. , 7. The device according to claim 6,
characterized in that the clamping plates (20-23) on the outlet side of the tendon (11-13) are provided with hammer-head-shaped anchor flange pieces (28) which overlap the outer end edge of the hollow body (14) for the purpose of load transfer into the hollow body (14) (Fig.2). 8. The device according to claim 3,
characterized in that the force transmission device comprises a conical sleeve (79) which extends in the longitudinal direction of the anchoring hollow body (74) and can be expanded by driving in a truncated cone-shaped wedge body (80), and in that the tensioning element is an intermediate one which penetrates the wedge body (80) in the longitudinal direction outer base of the wedge body and the distal end face of the conical sleeve (79) engaging tie rod (77) is provided (Fig.5a). 9. The device according to claim 3,
characterized in that the clamping body (96) is radially expandable by axial squeezing and is arranged between a respective inlet-side squeeze plate (73, 97), of which at least one plate (97) is axially displaceable at an end section of the hollow body (74) guided and by means of the clamping element (77) with defined adjustable Clamping force can be clamped against the other or pressed against the expandable clamping or squeezing body (96), this body at least from a lower limit of the pre-tension and preferably already in the relaxed state in the area between the squeeze plates (73, 97) and between the tendon (71) and / or further parts arranged in the interior of the hollow body. the remaining cavity completely fills up (Fig.6a). 10. The device according to claim 9,
characterized in that the squeeze body (96; 99) and the squeeze plates (73,97; 101,103) are provided with a number of passage channels or inlet and outlet openings (106, 107) for a corresponding number of tendons (71) (Fig .6a, 7a). 11. The device according to claim 10,
characterized in that the squeeze body (96; 99) has a central channel coaxial with bores of the squeeze plates (73,97; 101,103) through which the shaft (81) one with its anchor head on the outlet-side squeeze or. Abutment plate (101 or 73) supporting tie rod (77) passes through, which can be tensioned by means of a clamping nut (83), which rests on a spring-elastic body like a plate spring arrangement (84) in the central region of the outlet-side crushing or abutment plate (97 or 103) and that the passage channels for the tendons are grouped in a radial-symmetrical arrangement around the central anchor channel (FIGS. 6a-7b). 12. The device according to claim 10,
characterized in that the passage channels (119) for a number of tendons (117) are arranged in the central cross-sectional area of the anchoring hollow body (122) near the axis, and in that in radially symmetrical arrangement tensioning elements (130131) are provided which are outside the H hollow body (122 ) run or pass through channels within the squeeze body (116) (Fig, Ba). 13. Device according to one of the preceding claims 9, 10, 11 or 12,
characterized in that the tendons (71) are inserted in the anchoring area in axially supported clamping sleeves (104) made of a material with a strength that is sufficiently high for power transmission in the longitudinal direction, which have longitudinally extending slots (1o9) which axially symmetrically form the sleeve shell divide arranged sectors (110) (Fig. 7a, 7b). 14. The apparatus according to claim 13,
characterized in that the anchoring hollow body (102) is designed as a pot-shaped part, the squeeze plate (103) arranged on the outlet side of the tensioning members (71) is designed as an abutment plate firmly connected to the cylinder jacket, and in that the clamping sleeves (104) are designed by the individual Sheath sectors (110) have radially projecting flange pieces (108) lying on the outside of the abutment plate (103) and that the anchoring hollow body (102) has a radially projecting flange on the outlet side of the tendons (71) (Fig. 7a, 7b). 15. The apparatus according to claim 13,
characterized in that the inlet-side squeeze plate (123) and the anchoring hollow body (122) are firmly connected to one another, and in that the clamping sleeves (118) are supported on this squeeze plate (123) in the axial direction (FIG. 8a). 16. The apparatus of claim 13,
characterized in that at least the sectors (110) of the individual clamping sleeves (104) are firmly connected to one another at one end and preferably on the entry side of the tendons (71) (FIG. 7a). 17. Device according to one of the preceding claims 9, 10, 11 or 12,
characterized in that the tendons (117) are enclosed by a clamping body (118) made of a material with a strength sufficient for the transmission of force in the longitudinal direction, and in that the clamping body (118) on at least a part of its outer surface by the Squeeze expandable squeeze body (116) is enclosed (Fig.8a, 8b). 18, Device according to claim 17,
characterized in that the clamping body (118) is designed as a compact body which consists of the following materials which can be used alternatively or in combination: a. with fillers or fiber or fabric-reinforced plastic such as epoxy resin with mineral. Filler and / or steel fiber reinforcement. b. Plastic with sufficient strength for power transmission in the longitudinal direction c. Alloys based on lead or aluminum, which have a low hardness, d. Steel or aluminum, the body (11_) is provided with a design suitable for transmitting the transverse forces to the tendons (117) at least when using the materials mentioned under c and d through longitudinal slots (120, 121). 19. Device according to one of the preceding claims, characterized in that the squeeze body (96: 99: 110) is constructed on the basis of an elastomeric material such as polychloroprene, sulfochlorinated polyethylene or ethylene-VAC copolymers (FIGS. 6a, 7a, 8a). 20. The apparatus according to claim 19,
characterized in that the elastomeric material with a high degree of filling is filled with metal shot and / or with mineral fillers (Figures 6a, 7a, 8a). 21. The apparatus according to claim 19,
characterized in that the elastomeric material is provided with a reinforcement made of metal foil or metal fiber or metal fabrics. 22. The apparatus according to claim 19 in connection with one of the preceding claims 13, 14, 15 or 16,
characterized in that balls with an abutting arrangement are embedded in the elastomeric material. 23. Device according to one of the preceding claims in conjunction with claim 13 or claim 17, characterized in that the tendons (71; 117) on their sections passing through the clamping body (104; 118) with a jacket made of a flexible material, for example lead or Aluminum or an elastomer reinforced with a fiber or filler reinforcement, which fills a gap between the clamping body and the tendon. 24. Device according to one of the preceding claims, characterized in that between tendons (11-13; 51,52; 71; 117) with a preferably smooth surface and clamping bodies acting on these (20-22; 59-63; 87; 104 ; 118) made of solid material, a thin layer of fine-grained corundum splinters adhering to a thin carrier, preferably applied on one side to it, is provided. 25. The device according to claim 2, with an internally conical anchoring hollow body, the inner cross-section of which narrows towards the entry side of the tendon, and with an inside of the anchoring hollow body which is arranged there and directly adjoins the tendon and rests on the conical inner lateral surface of the anchoring hollow body, the radially supporting clamping body, which, under the influence of the prestress impressed on the tendon, experiences an axial displacement directed towards the prestressed concrete component and, as a result of this displacement, transmits to the tendon the transverse pressure required for its frictionally anchoring, characterized in that a stop device (219, 224 ; 234,236,23Z) is provided, which adjusts the axial displacement of the clamping body (221; 232) to a clamping element (221; 232) and the tendon (er (211; 231) Adequate transverse pressure is limited to the associated dimension. 26. The device according to claim 25,
characterized in that the anchoring hollow body ( ₂₁₃ ) is closed at the tendon entry side with a plate (219), and in that a buffer body is provided on the inside of the plate (219) on which the clamping body (221) can be supported in the axial direction . 27. The apparatus according to claim 26,
characterized in that the buffer body is designed as a hard foam layer (224) which can be compressed under the longitudinal tensile force acting on the clamping body by the provided clamping body displacement path. 28. The device according to claim 25,
characterized in that the clamping body is arranged between an abutment plate (234) on the inlet side, on which it is supported in the axial direction, and an abutment plate (236) on the outlet side, which has aligned through openings (241; 242) for one or more tendons (231 ) and are connected to one another in a tensile manner by at least one tie rod (237) which passes through the clamping body in the axial direction, the stop plates (236.) causing the axial displacement due to their abutment on the outer end face (243) of the anchoring hollow body (233) of the clamping body (232) and the distance between the stop plate (236) and the abutment plate (234) can be set to a defined value. 29. The device according to claim 23,
characterized in that the tension nut (239) of the tie rod (237) is supported on the stop plate (236) via a spring-elastic member (247) whose restoring force corresponds to the tensile force to be absorbed at approximately half its maximum spring travel. 30. The device according to claim 26 with a clamping body designed as a potting body,
characterized in that the tendons (311) to be anchored are held in the frustoconical potting body in these longitudinally penetrating clamping sleeves (321) which can be compressed in the radial direction and which are connected to the outside with radial flange pieces (331) support a pressure plate ( ₃₂₃ ) which is movable in the axial direction and which in turn lies directly on the outlet-side base surface (327) of the casting body (322) and covers it except for an edge gap ( _326. ) required for its axial displacement. 31. The device according to claim 30,
characterized in that the clamping sleeves have a jacket (333) divided by radial longitudinal slots (334) into sectors which are preferably arranged axially symmetrically and which at its end section (336) is of coherent block-shaped or tubular configuration. 32. Apparatus according to claim 30 or claim 31,
characterized in that, in the case of crowded central grouping and the tendons (311), the clamping sleeves are combined to form an overall block-shaped clamping sleeve body which, by means of longitudinal slots, the longitudinal center planes of which intersect in the axes of the tendons, the flexibility in the transverse direction of the tendons required for the transmission of the transverse pressure (311) is granted. 33. Apparatus according to claim 1 for end anchoring at least one rod used as a tendon in prestressed concrete construction made of fiber composite material, with a clamping member enclosing the tendon in the anchoring area, which is located in the radial and axial direction on the inner surfaces of an anchoring hollow body or a suitable recess of the Supported concrete component and at least by axial force can be prestressed to such an extent that it conveys a sufficient transverse pressure for the frictionally anchoring the tendon, the clamping body itself being part of a tensile force / lateral force conversion device which, via the tendon, introduces tensile forces into the force converting device with a specific conversion ratio in proportional lateral forces transformed, from which the transverse pressure of the clamping body and the tendon results, characterized in that at least part of the clamping body (430) as a body (427, 428; 461) which can be compressed by the tensile forces acting on the tendon (412) in the axial direction, e.g. ) is designed in which, in addition to the at least one tendon (412), via which the tensile forces converted into the transverse forces act in the event of a load, further supporting bodies or blind rods corresponding to the mechanical properties and dimensions of the tendon can be used and onto which for anchoring de s tendon (412) can be fixed in an analogous manner in the clamping body. 34. Device according to claim 33,
characterized in that the clamping body (430) is formed at least in two parts and comprises an axially displaceable wedge body part (427, 428; 461) and at least one further clamping body part (418-425; 462) which is one of the displacement of the wedge body part (427, 428; 461) experiences proportional transverse pressure, but in turn against one. Displacement is supported in the axial direction and that further tension members (411) are anchored in this clamping body part (418-425; 462). ! 35. Apparatus according to claim 33 or claim 34, characterized in that the axially movable wedge body part of the clamping body (430) comprises two oppositely arranged flat wedges (427, 428) pointing towards the entry side of the tendons with the wedge-edge end, between the parallel wedge surfaces those tendons (412) are held, on which the tensile forces converted into transverse forces act, and that the other part (418-425) of the clamping body, in which the further tendons (411) are anchored, preferably symmetrically to the axis plane (414) of the between the flat wedges (427,428) held tendons (412) grouped, essentially flat-plate-shaped clamping body elements (418-421,422-425), which limit parallel to the tendon axes clamping gaps (444) in which the further tendons (411) with the from the position of Wedge body part (427, 428) resulting transverse pressure are held, which in each case abuts the one flat wedge (427 or 428) of the wedge body part End clamp body element (426 or 429) is in turn designed as a flat wedge, which forms a wedge pair together with the wedge body flat wedge (427 or 428) (Fig. 13, 14). 36. Device according to one of the preceding claims 33-35, characterized in that between the inner wall of the cavity (431) receiving the clamping body (430) of the concrete component (413) or the anchoring hollow body (432) and the clamping body or between the wedge body part ( 427.428) and the other sprag part (418-425), which is supported in the axial direction, an approx. 2-4mm thick compensation layer (450,451) made of a flexible material, e.g. Polychloroprene, is provided (Fig. 13). 37. Device according to one of the preceding claims 33-36, characterized in that the tendons (411,412) held between the wedge members (427, 428) and / or the further clamping body elements (418-425) in an adhesive layer (452,453, 454 ) made of a resilient material, e.g. lead or an elastomer or synthetic resin mortar reinforced with a fiber or filler reinforcement or combinations of these materials. 38. Device according to claim 37,
characterized in that the surfaces of the clamping body elements (418-425) adjoining the adhesive layer (452, 453, 454) are roughened or have a groove-shaped profile. 39. Device according to claim 34,
characterized in that the clamping body is arranged in an anchoring hollow body (463) which has an inner cone tapering towards the entry side of the tendons (411,412), the clamping body (430) being formed in two parts with a frictionally holding a first group of tendons (411) , cylindrical inner clamping body part (462), which against axial displacement on a bottom plate (467) provided with through openings (468) for the tendons (411,412); is anchored hollow body (463) and with a on the inner clamping body part (462) slidably in the axial direction and on this and on the conical inner surface of the anchoring hollow body (463), frusto-conical outer clamping body part (461) into the second group of tendons (412) is embedded frictionally, and that at least this second clamping body part (461) is designed as a casting part. 40. Device according to claim 39,
characterized in that the inner cylindrical clamping body part (462) is also designed as a casting part which is offset from the outer clamping body part (461) by means of a thin-walled sliding jacket (469). 41. Device according to claim 1, for the end anchoring of at least one rod made of fiber composite material used as a tendon in prestressed concrete construction, with a clamping body enclosing the tendon in the anchoring area, which is located in the axial, ie direction of the tendon longitudinal axis and in the transverse direction to the inner surfaces of one of penetrate the tendon in the longitudinal direction, apart from through-openings for the tendon and an anchoring cavity that encloses this clamping sleeve, and can be pre-tensioned by axial force to such an extent that it provides sufficient transverse pressure for the frictionally anchoring the tendon, the clamping body itself being part of a tensile force / Shear force conversion device, which transforms tensile forces introduced into the device via the tendon with a certain conversion ratio into transverse forces proportional to this, from which a transverse pressure of the clamping body and the tendons s results, characterized in that the clamping body (530) is designed as a body consisting of a material that can be expanded by squeezing and completely filling the anchoring cavity (513), that the at least one tensioning member (511) is enclosed in one of the squeezing bodies (530) and this penetrating clamping sleeve (517; 542) is inserted, which, with radial flange pieces (528) on the outer side (529) of a slidable in the longitudinal direction of the tendon (511), apart from a narrow edge gap (523), the anchoring cavity on the outlet side of the tendon (511) closing squeeze plate (526) is supported, and that a tensioning device (531) is provided, with which the clamping body (530) by axial displacement of the squeeze plate (526) can be given the output pinch required for the frictional fixing of the tension member (511) under working load is. 42. Device according to claim 41,
characterized in that a cylindrical-pot-shaped anchoring hollow body (513) is provided, which limits the anchoring cavity in the radial and to the entry side of the at least one tendon (511) and in turn counteracts the tensile forces on the prestressed concrete component (512) acting on the prestressing member (511), which is closed on the entry side of the tendon (511) by a base plate (519) which is fixedly connected to the hollow body jacket (524; 548) and has a passage opening (518; 547) for the clamping sleeve (517; 542). 43. Device according to claim 42,
characterized in that the anchoring hollow body (513) on the outlet side of the tendon (511) over a partial length which corresponds to approximately 1/10 to 1/5 of the total length of the device (540), clearly (approximately 1.5 to 3 times ) has a larger inner diameter than in its entry-side part (548) which is closed off by the base plate (519). 44..Device according to claim 43,
characterized in that the squeeze body (530) has different mechanical properties, in particular different deformation properties, in layers seen in succession along the longitudinal axis ( ₅₄₁ ) of the device (540). ₄₅ . Device according to one of the preceding claims 42-44, characterized in that the anchoring hollow body (513) is designed as a formwork for the anchoring cavity (514) of the prestressed concrete component ( ₅₁₃ ) plastic injection molded part (for example made of polyamide or hard polystyrene).

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