EP2633137B1 - Anchoring the ends of tension members on reinforced concrete beams - Google Patents

Description

Technical area

The invention relates to reinforced concrete beam according to claim 1, which are equipped with a corresponding device and a method according to claim 7 for the final anchoring of said tension members to reinforced concrete beams.

State of the art

The reinforcement of structures, for example, in the renovation of existing structures, by attaching tension members made of fiber-reinforced plastic ribbon strips, which are glued under tension to the structure is known and has many advantages over the reinforcement of structures by means of steel structures. The introduction of force into the tension members takes place mainly at the ends of the tension member, after which the end anchorage of the tension members on the support structure is given particular importance.

The attachment of an end anchorage to a supporting structure is problematic, in particular in reinforced concrete plants, since the assembly of the final anchorage often takes place by screwing onto the supporting structure. Particularly problematic in this case is the attachment of end anchors on tightly reinforced reinforced concrete girders, in particular on those which also have a strained steel insert. Damage to the steel insert in such carriers by tapping the carrier for insertion of screw dowels can affect the strength of a reinforced concrete beam to a significant extent.

For example, end anchors, which are fastened by dowels to the structure described in WO 2004/038128 A1 and in WO 02/16710 A2 ,

Another end anchoring, which is described for example in DE 199 44 573 A1 , requires the attachment of slots on the surface of the structure.

Also known is the mere sticking of an end anchoring to a structural surface. However, this solution is associated with losses with respect to the load capacity of the end anchorage by the tensile load exerted by the tension member.

In a likewise known method for attaching an end anchorage to a framework made of reinforced concrete without damaging the steel insert, the steel insert is detected in a first step, so that the structure can be drilled past the steel insert. Subsequently, an end anchoring is tailored to the arrangement of the holes and mounted on the structure. Although such a method does not affect the load capacity of the structure, but the tapping of the carrier and the production of the end anchors to match the holes is very expensive.

With regard to the state of the art is still on US 5,479,748 A directed. There, a connector will be described to attach reinforcement cables to support members. US 5,479,748 A discloses a reinforced concrete beam according to the preamble of claim 1 and a method according to the preamble of claim 7.

Presentation of the invention

The object of the present invention is therefore to propose a reinforced concrete beam with at least one device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats, the device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats, without damaging a steel insert, simply attached to the reinforced concrete beam can still be and record a high tensile load.

According to the invention, this object is achieved by a reinforced concrete beam according to claim 1 and by a method according to claim 7.

• die Vorrichtung eine, an der Flanschunterseite horizontal positionierbare, Grundplatte und mindestens ein, entlang mindestens einer Flanschseite vertikal positionierbares, Seitenteil aufweist;
• die Grundplatte und/oder das mindestens eine Seitenteil mindestens ein Befestigungselement für ein Zugglied aufweist; und wobei
• das mindestens eine Seitenteil so eingerichtet ist, dass es, im Bereich der Verjüngung des Flanschs zum Steg hin, einen, gegen den Steg hin gerichteten, Vorsprung aufweist, welcher so angeordnet ist, dass er sich zumindest teilweise auf der Flanschoberseite abstützen kann.

According to the invention, a device for the final anchoring of tension members made of fiber-reinforced plastic flat strip lamellae on reinforced concrete girders, which has a web and a flange with a horizontal flange underside, two flange sides and two, of the Flange sides to the web towards extending, flange tops, having

• the device has a base plate that can be positioned horizontally on the flange underside and at least one side part that can be positioned vertically along at least one flange side;
• the base plate and / or the at least one side part has at least one fastening element for a tension member; and where
• the at least one side part is arranged to have, in the region of the taper of the flange towards the web, a projection directed towards the web, which is arranged so that it can at least partially rest on the flange top side.

The device for the final anchoring of tension members made of fiber-reinforced plastic flat strip lamellae can be easily mounted on a reinforced concrete beam and has many advantages over the end anchorages for tension members on reinforced concrete beams, which are known from the prior art.

Compared to the end anchors, which are screwed to the structural surface, the device has the advantage that it does not require drilling of the structural surface for setting the screw dowel, whereby there is no danger to weaken the structure by damaging the steel core.

Surprisingly, it has been found that the device, in particular by the overlapping of the at least one side part with the projection on the flange top of a reinforced concrete beam and the resulting train under tension of the tension member wedging the device on the carrier, can absorb a very high tensile load. The load capacity of the device according to the invention is comparable to that of bolted end anchors and exceeds the load capacity of only glued end anchors by a multiple.

Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of the dependent claims.

Brief description of the drawings

Reference to the drawings embodiments of the invention will be explained in more detail. Same elements are in the different figures with the provided the same reference numerals. Of course, the invention is not limited to the illustrated and described embodiments.

Figur 1

schematisch einen Querschnitt durch einen Stahlbetonträger;

Figur 2

schematisch einen Querschnitt durch eine Vorrichtung zur Endverankerung von Zuggliedern aus faserverstärkten Kunststoff-Flachbandlamellen;

Figur 3

schematisch einen Querschnitt durch einen Stahlbetonträger mit einer Vorrichtung mit nur einem Seitenteil;

Figur 4

schematisch eine Ansicht auf eine Vorrichtung zur Endverankerung von Zuggliedern;

Figur 5

schematisch einen Querschnitt durch einen Stahlbetonträger und die Montage einer mehrteiligen Vorrichtung zur Endverankerung von Zuggliedern;

Figur 6

schematisch einen Querschnitt durch einen Stahlbetonträger mit einer Vorrichtung mit seitlich liegenden Befestigungselementen für Zugglieder;

Figur 7

schematisch einen Querschnitt durch einen erfindungsgemässen Stahlbetonträger mit dargestelltem Bereich der ausgesparten Vertiefungen;

Figur 8

schematisch einen Querschnitt durch einen erfindungsgemässen Stahlbetonträger mit einer Vorrichtung mit zwei unten liegenden Befestigungselementen für Zugglieder;

Figur 9

schematisch einen Querschnitt durch einen erfindungsgemässen Stahlbetonträger mit einer Vorrichtung mit Seitenteilen in Form von Gewindestangen;

Figur 10

schematisch einen Teillängsschnitt eines erfindungsgemässen Stahlbetonträgers mit einer Vorrichtung und einem angelegten Zugglied;

Figur 11

schematisch eine Ansicht auf eine Vorrichtung mit Verlängerung;

Figur 12

schematisch eine Ansicht auf eine Vorrichtung mit einem hervorragenden Element;

Figur 13

schematisch einen Längsschnitt durch die Vorrichtung aus Figur 13;

Figur 14

schematisch einen Querschnitt durch eine Vorrichtung mit zwei hervorragenden Elementen;

Figur 15

schematisch einen Teillängsschnitt eines erfindungsgemässen Stahlbetonträgers mit einer Vorrichtung mit einem hervorragenden Element und einem angelegten Zugglied;

Figur 16

schematisch einen Teillängsschnitt eines erfindungsgemässen Stahlbetonträgers mit einer Vorrichtung mit Zugelement, Verlängerung und einem angelegten Zugglied;

Figuren 17a bis 17c

schematisch eine Darstellung der Schritte eines erfindungsgemässen Verfahrens zur Endverankerung eines Zugglieds an einem Stahlbetonträger.

Show it:

FIG. 1

schematically a cross section through a reinforced concrete beam;

FIG. 2

schematically shows a cross section through a device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats;

FIG. 3

schematically a cross section through a reinforced concrete beam with a device with only one side part;

FIG. 4

schematically a view of a device for the final anchoring of tension members;

FIG. 5

schematically a cross section through a reinforced concrete beam and the assembly of a multi-part device for the final anchoring of tension members;

FIG. 6

schematically a cross section through a reinforced concrete beam with a device with lateral fastening elements for tension members;

FIG. 7

schematically shows a cross section through an inventive reinforced concrete beam with Pictured area of the recesses recessed;

FIG. 8

schematically a cross section through a reinforced concrete beam according to the invention with a device with two lower fastening elements for tension members;

FIG. 9

schematically a cross section through an inventive reinforced concrete beam with a device with side parts in the form of threaded rods;

FIG. 10

schematically a partial longitudinal section of an inventive reinforced concrete beam with a device and an applied tension member;

FIG. 11

schematically a view of a device with extension;

FIG. 12

schematically a view of a device with a protruding element;

FIG. 13

schematically a longitudinal section through the device FIG. 13 ;

FIG. 14

schematically a cross section through a device with two protruding elements;

FIG. 15

schematically a partial longitudinal section of a reinforced concrete beam according to the invention with a device with a protruding element and an applied tension member;

FIG. 16

schematically a partial longitudinal section of an inventive reinforced concrete beam with a device with tension element, extension and an applied tension member;

FIGS. 17a to 17c

schematically a representation of the steps of an inventive method for the final anchoring of a tension member to a reinforced concrete beam.

In the figures, only the elements essential for the immediate understanding of the invention are shown.

Ways to carry out the invention

FIG. 1 shows a reinforced concrete beam 1, which has a web 2 and a flange 3 with a horizontal flange bottom 4, two flange sides 5 and two, from the flange sides to the web extending, flange tops 6, has. The reinforced concrete beam 1 further comprises a steel insert, consisting for example of a running in the transverse and longitudinal direction, unstressed steel core 7a and a longitudinally strained steel insert 7b. In addition to the significant increase in the tensile strength of reinforced concrete compared to concrete without steel inserts, the strained steel insert additionally increases the cracking moment of a reinforced concrete beam.

FIG. 2 shows a device which, at the flange underside of a reinforced concrete beam 1, as shown in FIG FIG. 1 is described, horizontally positionable, base plate 8 with a fastening element 9 for a tension member and two, along the flange 5 vertically positionable side parts 10 has. Furthermore, the side parts are set up so that, in the region of the taper of the flange towards the web, they each have a projection 11 directed towards the web. These projections are arranged so that they can be supported at least partially on the flange top 6. Furthermore, the device shown with an optional rib 24, which gives the device additional rigidity.

Another embodiment of the device, as it is already mounted on a reinforced concrete beam 1, is in FIG. 3 shown, said device next to the base plate 8 with the fastening element 9 for a tension member, only one side part 10 and correspondingly only one projection 11 has.

The device can be constructed in one or more parts. If the device is one which has two side parts, the device is designed in several parts or it has at least one joint, which makes it possible to bring the base plate, side parts and / or projections on a reinforced concrete beam into the desired position.

For example, the device which is in FIG. 2 is shown to a multi-part device in which the projections 11 are attached by means of screws and nuts each on one of the side parts 10. Such a device is applied from below to the reinforced concrete beam 1 and then secured by means of the projections 11 thereto.

Another multi-part embodiment of the device is for example in FIG. 4 shown. In this case, in addition to the base plate 8, to which the fastening element 9 is for a tension member, and the side parts 10 and the projections 11 are formed as plates which are in contact with the device when the device to the reinforced concrete beam 1 in contact. In the embodiment shown here, the ribs 24 not only have a stiffening function, but also serve to secure the projections 11 to the side parts 10 of the device.

If the device according to the invention does not have a stiffening rib, the projections can be attached directly to the side parts. For this purpose, the side parts preferably protrude over the flange sides In addition, for example, have holes through which pins, screws or the like can be passed for attachment of the projections.

Another multi-part embodiment of the device is for example in FIG. 5 shown. Shown here is a two-part device, as it is about to be applied to a reinforced concrete beam 1, according to the above description. The device shown comprises two base plates 8 with a fastening means 9 for a tension member, each of which has a side part 10 with a projection 11. Opposite one another, they form a device according to the invention. Such an embodiment typically further comprises means by which the two sub-devices can be fastened to each other or the attachment is made by inserting the tension member in the fastening element 9 provided for this purpose.

FIG. 6 shows, for example, a device which is mounted on a reinforced concrete beam 1. In this case, the device has a base plate 8 bearing against the flange underside 4 of a reinforced concrete beam 1 and two side parts 10 extending vertically along the flange sides 5. Furthermore, each of the two side parts has a fastening element 9 for a tension member and a respective projection 11. The projections are arranged so that they are supported on the flange top 6 and thus serve to secure the device to the reinforced concrete beam. Furthermore, the illustrated device is provided with an optional rib 24 for increasing the rigidity.

In order to achieve the most efficient reinforcement of the carrier by applying tension members made of fiber-reinforced plastic flat strip lamellae on reinforced concrete beam, the tension members and correspondingly the fastening means for the tension members are mounted in particular in the lower region of the side parts of the device or on the flange underside.

The device is typically made of metal, a metal alloy or other high strength material. The device preferably consists of steel.

Depending on the dimension of the reinforced concrete beam to be reinforced and depending on the need for reinforcement, the device has one or more fastening elements for tension members. In particular, the device has 1 to 4 fastening elements.

As fastening elements can be used any systems for introducing force into tension members, wherein the fastening element and the tension member which is to be fastened to the fastening element, must be coordinated.

If the fastening element is a clamping device in which the end of the tension member is clamped, for example, between two plates, no changes need to be made to the tension member for fastening.

If the fastener is a slot plate, a chuck is attached to each end of the tension member. The tension member is guided in such a fastener through the slot of the slit plate, so that the clamping head, viewed in the pulling direction of the tension member, is disposed behind the slit plate.

Suitable systems for introducing force into tension members are described, for example, as state of the art in the introduction to the description of the European patent application with the application number EP10173179.2 , Particularly suitable systems for introducing force into tension members are the subject of said European patent application. In particular, the fastening element is a slot plate which is used in conjunction with a tension member with a clamping head. Preferably, the slotted plate in the pulling direction of the tension member with Ridges or the like supported on the base plate or on the side part.

• die Vorrichtung eine, an der Flanschunterseite 4 horizontal verlaufende, Grundplatte 8 und mindestens ein, entlang mindestens einer Flanschseite 5 vertikal verlaufendes, Seitenteil 10 aufweist;
• die Grundplatte und/oder das mindestens eine Seitenteil mindestens ein Befestigungselement 9 für ein Zugglied aufweist; und wobei
• das mindestens eine Seitenteil im Bereich der Verjüngung des Flanschs zum Steg einen, gegen den Steg hin gerichteten, Vorsprung 11 aufweist, welcher sich zumindest teilweise auf der Flanschoberseite 6 abstützt.

Further exemplary embodiments of the device are described below in part in connection with reinforced concrete beams to which they are attached. Reinforced concrete beams with device are the subject of the present invention. The embodiment of the FIG. 1 discloses a reinforced concrete beam, which is not part of the invention. The device is still such as previously described. The embodiment of the FIG. 1 discloses a reinforced concrete beam which comprises a web 2 and a flange 3 with a horizontal flange bottom 4, two flange sides 5 and two flange tops 6 extending from the flange sides towards the web. The reinforced concrete beam 1 comprises at least one device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats, wherein

• the device has a, on the flange bottom 4 horizontally extending, base plate 8 and at least one, along at least one flange 5 vertically extending, side part 10;
• the base plate and / or the at least one side part has at least one fastening element 9 for a tension member; and where
• the at least one side part in the region of the taper of the flange to the web, a, directed against the web towards, projection 11 which is at least partially supported on the flange top 6.

Regardless of the embodiment of the reinforced concrete beam, which has such a device, the device is preferably glued to the reinforced concrete beam. In particular, two-component adhesives based on epoxy resin are used for this purpose, which can be high or low viscosity and possibly filled. For example, suitable adhesives under the trade names Sikadur® are commercially available from Sika Schweiz AG.

By gluing or pouring the gap between the reinforced concrete beam and the device, the base plate 8 is frictionally connected to the flange base 4 for transmitting shear and compressive forces. In order to allow a transmission of compressive forces between the projection 11 and the flange top 6, the device is typically made to fit the dimensions of the flange, this adapted during assembly or a gap between the projection 11 and flange top is filled by pouring or bonding non-positively. If the device is loaded on the fastening element 9 orthogonally to the cross-sectional plane, tangential deformations occur in the direction of stress in the boundary layer between the base plate 8 and the flange underside 4. In frictional, play-free contact between the projection 11 and the flange top 6, this results in a rotation of the entire device to the contact surface between the projection 11 and the flange top 6. In a sufficiently rigidly constructed device results from the rotation orthogonal to the contact surface between the base plate 8 and flange 4 directed pressure force , and a compressive force of the same amount between the projection 11 and the flange top 6. The compressive force in the interface between the base plate 8 and bottom flange 4 leads to a significant increase in the transmittable force in the tangential direction.

Typically, the reinforced concrete beam does not need to be drilled to secure the device. In particular, the web of the reinforced concrete beam is not pierced. According to the invention, the reinforced concrete beam has a recessed recess in the area where the device is applied and at least part of the device is placed in the recessed recess. The recessed recess can be located on the flange underside or on the flange sides. In certain cases, the recessed recess may also extend to the flange tops.

In particular, the recessed recess is located on those sides of the reinforced concrete beam to which the device to be mounted has the at least one fastening element for a tension member.

If the device has a base plate with a fastening element for a tension member, the recessed depression is located on the flange underside. If the device has fastening elements on at least one side part, the recessed recess is located on the at least one flange side on which the side part with the fastening element is applied.

FIG. 7 shows a reinforced concrete support 1 according to the invention, as already described in FIG FIG. 1 has been described, wherein here the areas are shown, over which the recessed recess 12, 13 can extend. Is at the location of the reinforced concrete beam, which has the recessed recess, the application of a device for the final anchorage of tension members made of fiber-reinforced plastic ribbon strips provided, in which the attachment of the tension member to the base plate, the reinforced concrete beam 1 in particular a recessed recess 12 at the Flange bottom 4 on. If the provision of a device is provided in which the attachment of the tension member takes place on a side part 10, then the recessed recess 13 is located in particular on the corresponding flange 5. If both side parts 10 have fastening elements, in particular there is a recessed recess on both sides.

The recessed recess has the advantage that the tension member can be applied without clearance to the reinforced concrete beam. As a result, a possible deflection of the tension member from the device to the surface of the reinforced concrete beam, for example, to the flange bottom, be reduced or eliminated completely. In particular, a recessed recess is also suitable when a preferred system, consisting of slot plate and clamping head, is used to introduce force into the tension member. In this case, the recess, against the pulling direction of the tension member, also extend over the area where the device according to the invention is applied so as to make room for the clamping head.

Another advantage of the recessed recess is the improved transmission of force from the device to the reinforced concrete beam, as the device can be supported at least partially, in the pulling direction of the tension member, against the flank of the recessed groove.

The recessed recess typically extends so far into the reinforced concrete beam that the device for the final anchorage of tension members of fiber reinforced plastic ribbon slats can be placed in the recess so that the applied tension member in the tensioned state with little or no deflection on the surface of the reinforced concrete beam , In particular, the depression extends at most up to the steel insert of the reinforced concrete beam.

FIG. 8 shows, for example, a device which is mounted on a reinforced concrete support 1 according to the invention. The illustrated reinforced concrete beam has a recessed recess on the flange bottom 4 and on both flange sides 5. The dashed line shows the outline of the reinforced concrete beam 1 in the places without recessed recess. The device has a, in the recessed groove on the flange underside of the reinforced concrete beam fitting, base plate 8 with two fastening elements 9 for tension members and two, in the recessed depressions along the flange 5 vertically extending side parts 10, each with a projection 11. The projections are arranged so that they are supported on the flange top 6 and thus serve to secure the device to the reinforced concrete beam. The recessed recess extends into the area of the steel insert 7 of the reinforced concrete beam.

FIG. 9 shows an embodiment of a device which is mounted on a reinforced concrete beam 1 according to the invention. Unlike the device, as in FIG. 8 is shown, here are the side parts 10 formed as threaded rods which connect the base plate 8 and the projections 11 together. Furthermore, it concerns the fastener 9 of in FIG. 9 illustrated device around a clamping device, wherein the end of the tension member is clamped between two plates.

If the side parts are threaded rods, a side part of the device consists in particular of at least two such threaded rods. This improves the stability of the device.

FIG. 10 also shows a device which is mounted on a reinforced concrete beam 1 according to the invention. The illustrated reinforced concrete beam has a recessed recess on the flange bottom 4, wherein the recess extends into the region of the steel insert 7. The device has a, in the recessed recess on the flange underside of the reinforced concrete beam 1 fitting base plate with a fastener 9 for a tension member and along the flange sides vertically extending side parts 10, each with a projection. The projections (not shown) are arranged so that they are supported on the flange top and thus serve to secure the device to the reinforced concrete beam. Further shows FIG. 10 the attached to the device tension member 16 which is mounted by means of clamping head 17 on the fastening element 9. The pulling direction 15 of the tension member 16 is indicated by an arrow.

If the device is mounted on a reinforced concrete beam according to the invention, which is provided with a recessed recess for the base plate, the force applied in the intended direction of pull 15 on the fastening element 9 will not only be due to tangential forces in the interface between base plate 8 and flange bottom 4, but also transmitted by pressure forces between the end face 25 of the base plate and the flank 26 of the recessed recess. The resulting from the application of a force in the intended direction of pull 15 on the fastener 9 rotation of the device generates compressive forces between the base plate 8 and the base 27 of the recess recessed. The compressive force directed orthogonally to the interface between the base plate 8 and the base 27 of the recessed recess results in an increase in the tangential resistance of the interface compared to a connection without compressive force.

Similarly, the forces behave in a device which has at least one fastening element 9 on at least one flange 5 of the reinforced concrete beam.

Another embodiment of the device is for example in FIG. 11 shown, wherein the base plate 8 of this device, compared to those in FIG. 4 , additionally comprises an extension 14 which extends in the intended pulling direction 15 of the tension member.

The resulting from the application of a force by the tension member 16 in the pulling direction 15 on the fastener 9 rotation of the device generated in addition to the compressive forces between the base plate 8 and the base 27 of the recess recessed also compressive forces between the extension 14 and the flange bottom 4. These on the Extension 14 applied to the flange underside, orthogonal to the concrete surface directed pressure force leads to an increase in the compressive strength of the concrete and thus to an increase in compressive forces between the end face 25 of the base plate and edge 26 of the recessed recess force.

An extension, as in FIG. 11 is shown on the base plate of the device, is independent of the embodiment of the device per se preferred. Furthermore, such an extension does not necessarily extend over the flange underside, but is typically mounted where on the one hand the reinforced concrete beam has a recessed recess for receiving the base plate or at least one of the side parts, depending on which of these parts provides a fastener for the tension member is.

Furthermore, the extension, as in FIG. 11 shown, consist of two parts, which are arranged on one side along the tension member. However, the extension may also extend over the area of the tension member between the tension member and the reinforced concrete beam or else such that the tension member is arranged between the extension and the reinforced concrete beam. If the extension between the tension member and reinforced concrete beam, the tension member is typically deflected by the height of the extension to the flange underside of the reinforced concrete beam.

In particular, the device is designed such that the base plate with the fastening element for the tension member and / or the at least one side part with the fastening element for the tension member has an extension which extends in the intended pulling direction of the tension member.

Typically, the extension is formed by the base plate and / or the side part having at least one, at least partially overlapping with the base plate, second plate, the second plate projects beyond the base plate in the intended direction of pull of the tension member.

A preferred embodiment of the device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats on reinforced concrete beams, which have a recessed recess at least on the flange underside, comprises a base plate with at least one, in particular in the direction of the side parts, outstanding element and is for example in the Figures 12 (View) and 13 (cross section) are shown. The base plate 8 of the device shown here has at least one protruding element 28, which is formed at least partially complementary to the recessed recess on the flange underside of the reinforced concrete beam. The protruding element 28 may be formed, for example, as a mandrel, which protrudes only over a part of the width of the reinforced concrete beam in this. In particular, however, the protruding element 28 is formed as a beam which extends over the entire width of the device.

Furthermore, the device may also have a plurality of outstanding elements 28, which are also designed in particular as mandrels or as beams. If the device is one which has a plurality of excellent elements, then they in particular spaced, parallel to each other beams. For example, shows FIG. 14 a device with two beams as outstanding elements 28, which are attached to the base plate 8.

Also in the case of the embodiment described here, in which the base plate has at least one protruding element 28, it is essential that the recessed recess extends maximally to the steel insert of the reinforced concrete beam. Therefore, the maximum height, by which the protruding element can protrude from the base plate, also corresponds to the distance between the flange underside of the reinforced concrete beam and its steel core.

FIG. 15 shows a device which is mounted on a reinforced concrete beam 1 according to the invention, wherein the illustrated reinforced concrete beam has a recessed recess on the flange bottom 4, which extends into the region of the steel insert 7. The recessed recess is typically formed so that it can accommodate the protruding element. Furthermore, the recess shown here, against the pulling direction 15 of the tension member 16, extends over the region on which the device is applied. This facilitates the use of a clamping head 17 for attaching the tension member 16 to the fastening element 9 of the device. Furthermore, the in FIG. 15 shown apparatus at the rear part of the base plate 8, an outstanding element 28 in the form of a bar, which projects into the recessed recess. The dashed lines show the invisible course of the reinforced concrete beam.

The embodiment of the invention in which the base plate has at least one protruding element 28 performs substantially the same function as the base plate and extension embodiment of the invention.

In both embodiments, in addition to the tangential forces in the interface between the base plate 8 and flange bottom 4, compressive forces between the end face 25 of the base plate and the end face of the protruding member 28 and the flank 26 of the recessed groove. Furthermore, that part of the base plate which, viewed in the pulling direction of the tension member, is located in front of the protruding element 28 acts in the same way as an extension of the base plate, in the embodiment without a protruding element.

The previously described embodiment of the invention, in which the base plate has at least one protruding element 28, is preferred because, among other things, it is simple to manufacture and easy to handle when mounted on a reinforced concrete beam.

For example, such a device can be produced by bending a metal plate into a U-profile or by joining several metal plates into a U-profile, for example by screwing, riveting, welding, gluing and the like. In the U-profile, the profile base forms the base plate and the two legs form the side parts. Thereafter, at least one excellent element, in particular a steel beam on the profile base, mounted in the transverse direction to the U-profile or to the longitudinal course of the reinforced concrete beam. In particular, the steel beam, viewed in the pulling direction of the tension member, in the rear region of the U-profile, preferably flush with the base plate mounted.

The in the Figures 10 and 15 shown reinforced concrete beams each have devices for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats, which have no clamping system or tension element for the tension member. Depending on the system which is used to introduce force into the tension member, such devices can be used at both ends of the tension member.

This is for example the case when the tension member is guided and stretched along the reinforced concrete beam and by the fastening elements of the devices at both ends of the tension member and the clamping heads are only after the tensioned tension member, in the pulling direction of the tension member, behind the fasteners, recognized. Also, it does not require a tension member when the fastener itself a clamping device for pinching the tensioned tension member represents. For example, these would be two plates between which the tensioned tension member would be clamped, as in FIG FIG. 9 is shown.

Regardless of the embodiment of the device or the reinforced concrete beam, which has such a device, the device is preferably keyed to the reinforced concrete beam. The wedging comes about in particular by the train, which is exercised by the tension member 16 in the pulling direction 15 on the device state.

In a further embodiment of the present invention, the device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats can be provided with a tension member for tensioning the tension member.

The tension element has the function of tensioning the tension member after it has been attached to the device according to the invention. This is typically done by threaded rods or by hydraulic presses or tractors.

For example, shows FIG. 16 a reinforced concrete beam 1 according to the invention with a device for the final anchoring of tension members made of fiber-reinforced plastic flat strip slats, as described above, wherein the device is equipped with a tension element 18 for tensioning the tension member 16.

The illustrated pulling element 18 comprises, like the device itself, a base plate, side parts and possibly projections. Furthermore, it comprises threaded rods 19, which are connected to the fastening element 9 for the tension member of the device. By tightening the nuts 20 train can be exercised on the fastener 9, whereby the tension member 16 is tensioned. The tension member 18 is connected via legs or plates 21 with the side parts 10 of the device.

In an alternative embodiment, the connection between the tension member 18 and device by means of Legs or plates 21 are dispensed with. Instead, the tension member 18 may be attached to the reinforced concrete beam.

The tension member 18 may be left after the tensioning of the tension member 16 on the reinforced concrete beam, or it may be removed after fixing the clamping head with tensioned tension member again. The clamping head is fixed, for example, by backfilling the area between the device according to the invention and the clamping head. For backfilling are materials based on cement or plastics such as epoxy resins.

1. i) Anlegen einer Vorrichtung an einen Stahlbetonträger 1, wobei
   • die Vorrichtung eine, an der Flanschunterseite 4 horizontal verlaufende, Grundplatte 8 und mindestens ein, entlang mindestens einer Flanschseite 5 vertikal verlaufendes, Seitenteil 10 aufweist;
   • die Grundplatte und/oder das mindestens eine Seitenteil mindestens ein Befestigungselement 9 für ein Zugglied aufweist; und wobei
   • das mindestens eine Seitenteil im Bereich der Verjüngung des Flanschs zum Steg einen, gegen den Steg hin gerichteten, Vorsprung 11 aufweist, welcher sich zumindest teilweise auf der Flanschoberseite 6 abstützt;
2. ii) Anlegen eines Zugglieds an das Befestigungselement 9;
3. iii) Spannen des Zugglieds.

Erfindungsgemäss wird am Stahlbetonträger 1, vor dem Schritt i) des Verfahrens, an mindestens der Stelle, wo die Grundplatte 8 mit dem Befestigungselement 9 für das Zugglied und/oder das Seitenteil 10 mit dem Befestigungselement 9 für ein Zugglied angelegt werden soll, eine Vertiefung 12, 13 ausgespart. Danach erfolgt das Anlegen der Grundplatte 8 mit dem Befestigungselement 9 für ein Zugglied und/oder des Seitenteils 10 mit dem Befestigungselement 9 für ein Zugglied in der ausgesparten Vertiefung.Furthermore, the present invention relates to a method for the final anchoring of tension members made of fiber reinforced plastic ribbon strips on reinforced concrete beams 1, which a web 2 and a flange 3 with a horizontal flange bottom 4, two Flanschseiten 5 and two, from the flange sides to the web extending flange tops 6, comprising the steps

1. i) applying a device to a reinforced concrete beam 1, wherein
   • the device has a, on the flange bottom 4 horizontally extending, base plate 8 and at least one, along at least one flange 5 vertically extending, side part 10;
   • the base plate and / or the at least one side part has at least one fastening element 9 for a tension member; and where
   • the at least one side part in the region of the taper of the flange to the web has a, directed against the web towards, projection 11 which is at least partially supported on the flange top 6;
2. ii) applying a tension member to the fastener 9;
3. iii) tensioning the tension member.

According to the invention, on the reinforced concrete beam 1, before step i) of the method, at least at the point where the base plate 8 is to be applied with the fastening element 9 for the tension member and / or the side part 10 with the fastening element 9 for a tension member Recess 12, 13 recessed. Thereafter, the application of the base plate 8 takes place with the fastening element 9 for a tension member and / or the side part 10 with the fastening element 9 for a tension member in the recessed recess.

When the device is a device having a protruding member, the device is applied to the reinforced concrete beam so that the protruding member protrudes into the recessed groove.

The recessed recess extends maximally to the steel insert of the reinforced concrete beam.

The recess of the recess can be made in any way, while it must be ensured that the steel insert is not damaged in the reinforced concrete beam. For example, the recess is cut out of the concrete or milled out. Preferably, the recess of the recess is made with a high-pressure water jet.

In the Figures 17a, 17b and 17c the main steps of the inventive method are shown.

Figure 17a shows a reinforced concrete beam 1 with steel insert 7, as has been previously described. Shown are the flange bottom 4 and a flange 5. The web of the reinforced concrete beam and the flange tops are not shown. Further shows Figure 17a a high-pressure water jet system 22, by means of which a recess for the device is recessed on the flange underside and on the flange sides of the reinforced concrete beam. Furthermore, a recess for the clamping head is recessed.

FIG. 17b shows the reinforced concrete beam 1 with the recesses 12 recessed on the lower flange side 4 and 13 on the flange sides 5 and further the recess which has been recessed for the clamping head in the recessed recesses 12 and 13, which for the device are provided, an adhesive 23 has been applied for gluing the device to the reinforced concrete beam.

Further shows FIG. 17b a device for the final anchoring of tension members made of fiber-reinforced plastic flat strip lamellae consisting of a base plate 8 with a fastening element 9 for the tension member, two side parts 10, two not yet attached to the side parts projections 11 and an extension 14. The extension is formed in two parts, so that space for the tension member is maintained in the middle.

FIG. 17c shows the reinforced concrete beam 1, to which the device for the final anchoring of tension members made of fiber-reinforced plastic ribbon slats was attached. After positioning the device on the reinforced concrete beam, the projections 11 were attached to the side parts with screws and thus secure the device to the reinforced concrete beam. The glue in FIG. 17b is illustrated, also contributes after its curing to the attachment of the device.

FIG. 17c This is provided at its illustrated end with a clamping head 17, which, viewed in the pulling direction 15 of the tension member, behind the fastening element 9, in this case a slotted plate, is arranged.

By the train, which is exerted by the tension member 16 in the pulling direction 15 on the device, it can lead to a wedging of the device with the reinforced concrete beam. The degree of wedging depends on the geometry of the device and on the method of bonding the device to the reinforced concrete beam. The wedging can have a positive effect on the stability of the device.

The tensioned tension member 16 is finally glued in the tensioned state with the reinforced concrete beam. Suitable adhesives for bonding the tension member to the reinforced concrete beam are in particular two-component adhesives based on epoxy resin, as are commercially available, for example, under the trade names Sikadur® from Sika Schweiz AG.

LIST OF REFERENCE NUMBERS

1

Reinforced concrete beam

2

web

3

flange

4

lower flange

5

flange

6

flange top

7

steel insert

7a

unstressed steel core

7b

strained steel insert

8th

baseplate

9

Fastening element for tension member

10

side panel

11

head Start

12

Recessed recess on the flange underside

13

Recessed recess on the flange side

14

renewal

15

Pull direction of the tension member

16

tension member

17

clamping head

18

tension element

19

threaded rod

20

nut

21

leg

22

High pressure water jet system

23

adhesive

24

rib

25

Face of the base plate

26

Flank of the recessed groove

27

Base of the recessed well

28

excellent element

29

Face of the outstanding element

Claims (10)

1. Reinforced concrete beam, which exhibits a connecting piece (2) and a flange (3) with a horizontal flange underside (4), two flange sides (5) and two flange upper sides (6) running from the flange sides to the connecting piece,
   wherein the reinforced-concrete beam (1) comprises at least one device for anchoring the ends of tension members made of fiber-reinforced plastic flat-strip lamellas, wherein

   - the device exhibits a base plate (8) running horizontally on the flange underside (4) and at least one lateral piece (10) running vertically along at least one flange side (5);

   - the base plate and/or the at least one lateral piece exhibits at least one attachment element (9) for a tension member; and wherein

   - the at least one lateral part in the area where the flange tapers toward the connecting piece, exhibits a protrusion (11) directed toward the connecting piece, which is at least partially braced on the flange upper side (6), characterized in that the reinforced-concrete beam (1), in the area where the device is installed, exhibits a recessed pocket (12, 13) and at least one part of the device is installed in the recessed pocket.
2. Reinforced concrete beam according to claim 1, characterized in that the reinforced concrete beam (1) at least in the area where the base plate (8) with the attachment element (9) for the tension member and/or the side part (10) with the attachment element (9) for a tension member is arranged, exhibits the recessed pocket (12, 13) and the base plate (8) with the attachment element (9) for a tension member and/or the lateral part (10) with the attachment element (9) for a tension member are installed in the pocket.
3. Reinforced concrete beam according to claim 1 or 2, characterized in that the reinforced concrete beam (1) exhibits the recessed pocket (12) on the flange underside (4) and the base plate (8) with the attachment element (9) for a tension member exhibits at least one protruding element (28), with the at least one protruding element (28) extending into the recessed pocket.
4. Reinforced concrete beam according to claim 3, characterized in that the recessed pocket (12) and the projecting element (28) at least in part are designed to be complementary to each other.
5. Reinforced concrete beam according to one of claims 1 to 4, characterized in that the device is adhesively bonded to the reinforced concrete beam (1) .
6. Reinforced concrete beam according to claim 2, characterized in that the device exhibits an extension (14), which extends, in the intended tensile direction (15) of the tension member, over the recessed pocket (12, 13) to the flange underside (4) and/or to the at least one flange side (5) of the reinforced concrete beam.
7. Method for anchoring the ends of tension members made of fiber-reinforced plastic flat-strip lamellas on reinforced-concrete beams (1), which comprise a connecting piece (2) and a flange (3) with a horizontal flange underside (4), two flange sides (5) and two flange upper sides (6) running from the flange sides to the connecting piece, comprising the following steps:

   i) installing a device on a reinforced-concrete beam (1), wherein

   - the device exhibits a base plate (8) running horizontally on the flange underside (4) and at least one lateral part (10) running vertically along at least one flange side (5);

   - the base plate and/or the at least one lateral part exhibits at least one attachment element (9) for a tension member; and wherein

   - the at least one lateral part, in the area of the tapering of the flange to the connecting piece, exhibits a protrusion (11) directed toward the connecting piece, which is braced at least partially on the flange upper side (6);

   ii) installation of a tension member on the attachment element (9);

   iii) placing the tension member under tension, characterized in that on the reinforced concrete beam (1) in the area where the device is to be installed, a pocket (12, 13) is recessed and at least a part of the device is installed in the recessed pocket.
8. Method according to claim 7, characterized in that on the reinforced concrete beam (1), at least in the area where the base plate (8) with the attachment element (9) for the tension member and/or the side part (10) with the attachment element (9) for a tension member is to be installed, the pocket (12, 13) is recessed, and the base plate (8) and/or the lateral part (10) with the attachment element (9) for a tension member is installed in the pocket.
9. Method according to claim 7 or 8, characterized in that on the reinforced concrete beam (1), at least in the place where the base plate (8) with the attachment element (9) for the tension member is situated, at least the recessed pocket (12, 13) exhibits and the base plate (8) with the attachment element (9) for a tension member exhibits at least one protruding element (28) and the device is so constructed that the protruding element (28) extends into the pocket.
10. Method according to one of claims 7 to 9, characterized in that a wedging of the device with the reinforced concrete beam (1) goes hand in hand with placement of tension on the tension member.

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