EP2247827A1

EP2247827A1 - Improved sliding anchor

Info

Publication number: EP2247827A1
Application number: EP08716147A
Authority: EP
Inventors: Michael Meidl; François Charette
Original assignee: Atlas Copco Mai GmbH
Current assignee: Atlas Copco Mai GmbH
Priority date: 2008-02-29
Filing date: 2008-02-29
Publication date: 2010-11-10
Anticipated expiration: 2028-02-29
Also published as: EP2247827B1; ES2371019T3; KR20100134626A; IL207806A0; CL2009000192A1; PE20100133A1; JP4980469B2; MX2010009475A; SI2247827T1; DK2247827T3; CA2715794C; BRPI0822279A2; US20110002745A1; PL2247827T3; AU2008351618A1; CN101970798A; HK1149784A1; CN101970798B; US8465238B2; PT2247827E

Abstract

The invention relates to a sliding bolt (10) for introducing into a bore, having an anchor rod (12), on which is disposed a sliding control element (14) with a through-opening (18), through which the anchor rod (12) extends, wherein the sliding control element (14) comprises a sliding body cage (16) having at least one recess (20) for receiving a sliding body (22) that is in contact with the lateral surface of the anchor rod (12), and having an anchor plate (24), which is intended to lie against a region surrounding the mouth of the bore once the sliding bolt (10) has been introduced into the bore. In contrast to conventional sliding bolts, the anchor plate (24) is in load-transferring connection with the sliding body cage (16), with the result that it is easily possible to provide a device that indicates a sliding path of the sliding bolt that is still available.

Description

Improved slip anchor

The invention relates to a sliding anchor for insertion into a bore, wherein the sliding anchor an anchor rod, on which a sliding control element is arranged with a through hole through which extends the anchor rod, and an anchor plate, which abutment to a surrounding the mouth of the bore area is determined when the sliding anchor has been inserted into the bore, and wherein the sliding control element comprises a sliding body cage with at least one recess for receiving a standing in contact with the lateral surface of the anchor rod slider. Such a sliding anchor is known from WO 2006/034208 Al.

Sliding anchors belong to the group of so-called mountain anchors. Rock anchors are used in mining, tunneling and foundation engineering to stabilize the wall of a tunnel, tunnel or embankment. For this purpose, a hole in the rock is driven from the tunnel or tunnel, the length of which is usually between two and twelve meters. A rock bolt of appropriate length is then inserted into this hole, the end area of which is permanently fastened by means of mortar, special resin adhesives or by mechanical spreading in the hole. On the protruding out of the bore end of the anchor usually an anchor plate is inserted, which is clamped with a nut against the wall of the tunnel or tunnel. In this way, loads acting in the area of the tunnel wall or tunnel wall can be introduced into deeper rock layers. In other words, with the help of such rock anchors wall-remote rock layers are used for load transfer in order to minimize the risk of collapse of the tunnel or tunnel.

Conventional rock anchors can transmit a maximum load corresponding to their constructive design and, if this load is exceeded (so-called.

Breaking load). In order to avoid such, for example, caused by rock shifts total failure of a set rock anchor as possible, so-called sliding anchors have been developed that give defined defined when exceeding a predetermined load, ie can increase their length within certain limits, acting on a rock tension to a level which can still be transferred from the anchor. Such sliding anchors have a structurally predetermined sliding distance when exceeding the predetermined load can be passed through, ie the total length of the sliding anchor can extend through the defined yielding at elevated load by a maximum of this sliding distance. It is desirable to be able to determine quickly and unambiguously by a visual inspection of the sliding anchor, whether a certain sliding anchor has yielded already defined, ie his sliding is already partially or completely used up, because from this information can be drawn conclusions about occurred rock movements and for others can better plan the timing at which a set slip anchor may need to be replaced or supplemented by other rock anchors. If, in fact, the sliding section of the sliding anchor is completely used up, further increases occur

Rock movements, the sliding anchor can fail after exceeding its breaking load.

The invention has set itself the task of providing a sliding anchor, which offers better structural conditions for the installation of a device that indicates a still available sliding distance in a fast and secure detectable manner.

Based on the above-mentioned, known sliding anchor this object is achieved in that the anchor plate is in force-transmitting connection with the Gleitkörperkäfig of the sliding control. In other words, the armature plate is interlocked with the Gleitkörperkäfig for transmission of particular tensile and compressive forces, so that when exceeding the predetermined load of the Gleitankers the sliding control slips over the anchor rod, whereas in the known embodiment, the sliding control remained stationary and the Anchor rod slid through the sliding control when the predetermined load was exceeded. In the conventional, known sliding anchor the anchor plate, which is supported from the outside against the rock wall to be secured, firmly connected to the anchor rod. If it comes by rock movements to a pressure on the anchor plate, which exceeds the predetermined load of the sliding anchor, the anchoring rod connected to the anchor plate slips through the slide control to the outside to give defined by the thus obtained extension of the sliding anchor the load defined. From the outside, however, such an extension of the sliding anchor, ie the successively taking into account the rock movements consumption of the available sliding section, not readily apparent. Only if, for example, a wire has been installed when setting the gliding anchor can a statement be obtained as to whether rock movements have occurred and which part of the slide has been consumed as a result already.

In the sliding anchor according to the invention, however, the anchor plate is in kraft tragber- 5 bearing connection with the Gleitkörperkäfig, so that when rock movements occur and the resulting pressure on the anchor plate, the sliding control slips over the anchor rod when the predetermined load of the sliding anchor is exceeded. By contrast, the anchor rod remains stationary and its free end situated in the region of the bore mouth slips into the sliding anchor during the sliding process. In this way, it is easily possible to determine whether a particular slip anchor has already passed slip conditions and which measure of its sliding distance has already been used up.

According to one embodiment of the sliding anchor according to the invention the Gleitkör- is i5 perkäfig part of a mounting adapter, which serves for fixing the anchor plate against the region of the rock wall, which surrounds the bore mouth. In this embodiment, the Gleitkörperkäfig and thus the entire sliding control is relatively close to or even in the bore mouth. Preferably, in such an embodiment, a protective tube surrounding the anchor rod concentrically extends from the anchor plate into the bore to protect the anchor rod, in particular from crushing by shifting rock plates. The protective tube may extend into the region of the bore-side end of the sliding anchor and is preferably made of metal, in particular steel, or plastic. 5

Preferably, the anchor rod protrudes through the anchor plate and the mounting adapter through out of the hole. If the length of the section of the anchor rod protruding from the bore is known, later changes occurring due to rock movements can easily be verified on the basis of the then shortening section. In order to facilitate the detection of such changes, the protruding from the bore portion of the anchor rod is preferably provided with one or more markings, by means of which a still available sliding can be visually detected. For example, the section of the anchor rod projecting out of the bore can be provided with an equal pitch in the manner of a meter bar, so that the sliding section already consumed in the course of rock movements can be read off directly. In a modified embodiment, the markings are color markings, wherein preferably one of the anchor plate next region of the anchor rod green, an axially adjacent thereto yellow area and a subsequent, the free end of the anchor rod comprehensive area is marked in red. When setting the sliding anchor, this is set so that all three color-coded areas of the anchor rod are visible from the outside. During operation, the green area can then "disappear" due to rock movements, ie move into the sliding anchor, then the yellow area and finally the red area. As long as the green area or part of it is still visible from the outside, this indicates that everything is fine. If only the yellow area (or a part of it) and the red area are visible from the glide anchor, this indicates that this gliding anchor can be observed more intensely, as obviously more rock movements take place. If only the red area sticks out of the glide anchor, this indicates that the situation is starting to get critical and that it is necessary to think about replacing the glide anchor soon or setting additional glide anchors.

In another embodiment of the sliding anchor according to the invention, a protective tube concentrically surrounding the anchor rod extends from the anchor plate in the direction of the bore-side end of the anchor rod (ie inwardly into the bore) and is fixed at one end to the slider cage and at its other end to the anchor plate , The protective tube thus serves to transmit power between the anchor plate and the Gleitkörperkäfig. In principle, all types of connection which ensure the transmission of force between the interconnected parts are suitable for fixing the protective tube to the sliding body cage or to the anchor plate. For example, one end of the protective tube may be welded to the sliding body cage. But it can also be screwed or jammed with the Gleitkörperkäfig. An embodiment in which the protective tube integrally connects to the Gleitkörperkäfig is also possible. To fix the protective tube to the anchor plate may serve a mounting adapter, which is screwed onto the free end of the protective tube. Other types of connection known to a person skilled in the art are also possible.

If a mounting adapter is used for fixing the free end of the protective tube to the anchor plate, then this preferably has a coaxial with the anchor rod through-hole, through which the anchor rod can extend. Preferably, then a stop element is mounted on the free end of the anchor rod or in the region thereof, whose diameter is greater than the diameter of the passage opening. In this way, the sliding control Do not slide down from the anchor rod. For example, the stopper is screwed onto the end portion of the anchor rod or otherwise secured nut. If the stop element strikes the sliding control element, a further defined yielding of the sliding anchor is no longer possible. The sliding anchor can then be charged to its resulting from the structural design breaking load and will fail after exceeding the same, for example, then the anchor rod will tear.

In an initial state of the sliding anchor, the stop element is preferably located in the through-hole of the mounting adapter. In an advantageous embodiment, the outer-side end face of the stop element in the initial state of the sliding anchor terminates flush with an outer edge of the mounting adapter surrounding the end face. If rock movements occur which lead to an extension of the sliding anchor, the stop element moves into the sliding anchor, more precisely into the passage recess, which is clearly visible from the outside.

According to one embodiment of the previously discussed embodiment, the anchor rod or an extension of the same out of the mounting adapter and is preferably provided with one or more markings, which is still a

Specify available sliding distance. These markings can be made as stated above in connection with the first embodiment. Alternatively, in the region of the free end of the anchor rod, a sliding link detection element may be fastened, in particular a band, a wire, a thread or the like. In a change in length of the sliding anchor as a result of sliding of the sliding control element, the sliding distance detection element is then drawn into the sliding anchor accordingly, so that the already used sliding distance can be easily determined by a comparison with the originally outstanding length of the Gleitstreckenerfassungselements.

In the aforementioned embodiments in which a force-transmitting protective tube extends between the anchor plate and the Gleitkörperkäfig, another protective tube may be provided which extends from the sliding control into the region of the bore-side end of the anchor rod and surrounds the anchor rod concentrically. As in the former embodiment, this protective tube serves to protect the anchor rod, in particular against crushing by shifting rock slabs, and is preferably made of metal, in particular steel, or plastic.

In slidable anchors of the type mentioned, it is also desirable that the force at which the slip anchor defines yielding, can be adjusted as accurately as possible and fluctuates as little as possible during the yielding to allow on the one hand a precise structural design of the rock anchor and on the other to be able to realize as good as possible predictable behavior during operation. Also, the so-called breakaway force, so the force from which exceeds the sliding anchors defines yielding, be repeatable, so that the load of the sliding anchor during different, temporally spaced phases of such a defined yielding does not change uncontrollably.

To achieve this, in each of the aforementioned embodiments, each recess for receiving a slider in Gleitkörperkäfig preferably arranged tangentially to the lateral surface of the anchor rod, and further protrudes the Mantelhüllfläche each recess a predefined measure in the free cross section of the through hole, and finally fills each slider the cross section the recess assigned to him. The term "tangential to the lateral surface of the anchor rod" in the present case means no exact tangentiality in the mathematical sense, in which the mantle envelope surface of the recess would affect only the lateral surface of the anchor rod, but there is a substantially tangential arrangement of the specific recesses for receiving sliding bodies The lateral surface of the anchor rod is meant in which the central longitudinal axis of each recess is skewed to the central longitudinal axis of the anchor rod, wherein in a projection of the central longitudinal axis of the anchor rod and the central longitudinal axis of any recess for receiving a slider, these two axes may be orthogonal to each other, but need not. The central longitudinal axis of a recess for receiving a slider can therefore lie in a plane which intersects the central longitudinal axis of the anchor rod at right angles (then the axes in question in the projection described are orthogonal to each other), but it can also in one to the central longitudinal axis of the tie rod sloping plane lie.

Such an embodiment of a sliding anchor according to the invention has a number of advantages. By the Mantelhüllfläche each provided for receiving a slider recess in Gleitkörperkäfig a predefined dimension in the free cross section of the passage opening of the sliding control protrudes, with the help of this Maßes the clamping force with which the slider or hold the extending through the passage opening anchor rod, are preset very accurately. Furthermore, this once set clamping force after a single startup process can be achieved with repeated accuracy, because each slider fills to the usual tolerances the cross section of its associated recess, so that the predefined measure with which each slider in the free cross section of the through hole projects, does not change during operation of the sliding anchor, in particular not even if it comes in operation to several time-separate sliding phases of the sliding control. Finally, the power transmission between the optionally sliding sliding control element and the anchor rod is advantageously solved, since due to the cross section of the recesses filling sliding body to no material deformation on the sliders and the Gleitkörperkäfig, but only on the anchor rod. The prerequisite for this is, of course, that - as already cited in the prior art - the material hardness of the slider is greater than that of the anchor rod.

Other influencing factors with which the clamping or breakout force can be influenced are the shape of the sliding body and the sliding body cage, the number of sliding bodies, the nature of their surface in contact with the anchor rod, the material pairings between the sliding body and the tie rod and between sliding body and sliding body cage, as well as the shape and type of the surface of the anchor rod.

In principle, the sliding anchor according to the invention already works with a recess and a sliding body arranged therein. Preferably, however, a plurality of recesses are arranged in the sliding body cage, which are advantageously distributed around the circumference of the anchor rod around, in particular evenly distributed around the circumference. By means of a plurality of recesses and according to a plurality of sliding body, the desired breakaway force can be set even more precisely, also can be realized with multiple recesses and sliding bodies arranged therein in a simple way higher clamping or breakaway forces. A uniform distribution of the recesses and sliding bodies around the circumference of the anchor rod distributes the loads acting on the anchor rod more uniformly.

Each of the plurality of recesses may be arranged in the sliding body cage at a different level, ie in a respective separate cross-sectional plane of the sliding body cage. To achieve a more compact design of the sliding control However, preferably a plurality of recesses are arranged in a cross-sectional plane of the Gleitkörperkäfigs. The number of recesses possible in a cross-sectional plane depends on the dimension of the recesses and the dimension of the sliding body cage. In one embodiment of a sliding anchor according to the invention

5, three recesses are arranged in a cross-sectional plane, but it may also be more than three such recesses in a larger sized sliding anchor with a correspondingly larger sliding control. Furthermore, it is also preferable to arrange a plurality of recesses in groups in various cross-sectional planes of the slider cage, also from the viewpoint of achieving a compact construction and uniform load distribution. Such a configuration is preferably selected when the spatial relationships do not allow an arrangement of the desired number of recesses in a cross-sectional plane. For example, in another embodiment of the sliding anchor according to the invention, in each case three recesses are arranged in two different cross-sectional segments of the sliding body cage. The recesses of the different cross-sectional planes are advantageously angularly offset from one another in such a way that the sliding bodies arranged in the recesses of one cross-sectional plane contact other regions of the lateral surface of the anchor rod than the sliding bodies present in the or the other cross-sectional planes.

20

In the context of the present invention, the shape of the sliding body used can be chosen almost arbitrarily. For example, the sliders may be spherical or may have a tapered outer shape, e.g. tapered roller-shaped. According to a preferred embodiment, the sliders have a circular 5-cylindrical shape, so are roll-shaped. Furthermore, the lateral surface of each

Sliding body be cambered, ie bulged outwards, for example in the manner of a wine barrel. Also prismatic sliding body are possible. It is understood that the shape of the recesses must be adapted to the sliding bodies used at least to the extent that each slider is received in its recess substantially free of play o. In general, the shape of the recess will correspond to the shape of the slider used, ie a circular cylindrical slider will be arranged in a circular cylindrical recess, a conical slider in a conical recess, etc., but this match is not mandatory. In preferred embodiments of sliding anchors according to the invention, a mixing and anchoring element is fastened to the bore-side end of the anchor rod. When adhesive resins are applied to two-component tenbasis be used, the two components are usually introduced in the form of adhesive cartridges in the bore, in which the two components are housed, for example, in two mutually concentric chambers separated from each other. When setting the anchor, the mixing and anchoring element then first destroys the chambers formed, for example, from a plastic film, and a simultaneous or subsequent turning of the anchor rod then leads to intimate mixing of the two components, which subsequently cure rapidly to form the finished adhesive resin.

In preferred embodiments of the sliding anchor according to the invention, the mounting adapter is formed at its free end for coupling with a mounting device which rotates the mounting adapter and thus the Gleitkörperkäfig, the anchor rod and the mixing and anchoring element during insertion of the sliding anchor into the bore. In such embodiments, the attachment of the mounting adapter to the slider cage and to the anchor plate must be designed so that rotational forces can be transmitted.

A preferred embodiment of a sliding anchor according to the invention is explained in more detail below with reference to the accompanying schematic figures. It shows:

1 shows a longitudinal section through a preferred embodiment of a sliding anchor according to the invention according to a first embodiment,

2 shows a first embodiment of a sliding body cage, as used in a sliding control element of a sliding anchor according to the invention,

3 shows the section III-III of Figure 2,

Figure 4 shows a second embodiment of a Gleitkörperkäfigs, as in the

Sliding control of the sliding anchor shown in Figure 1 is used,

5 shows the section V-V of Figure 4,

FIG. 6 shows the section VI-VI from FIG. 4, 7 shows a view corresponding to FIG. 5, but with sliding bodies inserted into the sliding body cage, FIG.

8 shows a view corresponding to FIG. 6, likewise with sliding bodies inserted into the sliding body cage, and FIG

Figure 9 is a plan view of a preferred embodiment of a sliding anchor according to the invention according to a second embodiment.

Shown in Figure 1 is a slip anchor, generally designated 10, which is provided for insertion into a rock hole, not shown, for example, to stabilize the wall of a tunnel or tunnel. The central element of this sliding anchor 10 is an anchor rod 12, which represents the load-bearing component of the sliding anchor 10 and whose length determines the length of the sliding anchor 10. In the illustrated embodiment, the anchor rod 12 is a solid, continuous steel rod with a circular cross-section and a diameter of 12 mm and a smooth lateral surface whose length is here two meters. However, depending on the desired load transfer capability, the diameter of the anchor rod 12 may be less than or greater than 12 mm, and also its length may be shorter or longer than previously specified, depending on the conditions of use. Also, the lateral surface of the anchor rod 12 does not have to be smooth, but can be roughened, grooved, etc., for example. Although anchor rods of circular cross-section are preferred, the invention is not limited thereto, the cross-section of the anchor rod may for example be square, polygonal, etc.

On a portion of the anchor rod 12, which is provided for introduction into the rock hole, not shown, a sliding control element 14 is arranged, the basic structure of which better apparent from Figures 2 and 3. The sliding control member 14 serves to allow a limited Relatiwerschiebung between the anchor rod 12 and the sliding control member 14, so that the sliding anchor 10 occurring after its setting rock shifts can better cope and not prematurely failed.

The sliding control element 14 has a hollow cylindrical Gleitkörperkäfig 16 with a central, axially extending through hole 18 (see Fig. 2), which is slightly stepped in the example shown and extending through the assembled state of the sliding anchor 10 of the anchor rod 12. As can be seen from the section shown in FIG. 3, three recesses 20 are formed uniformly around the circumference of the sliding body cage 16 in the form of circular cylindrical bores which are arranged in such a way that their jacket surface projects slightly into the free cross section of the through opening 18. In other words, a measure X, which defines the distance between the center M of the through-hole 18 and the central longitudinal axis of each recess 20, is slightly smaller than the sum of the radius R of the through-hole 18 and the radius r of the recess 20.

10

The recesses 20 are arranged substantially tangentially to the lateral surface of the anchor rod 12, that is, their central longitudinal axes are skewed to the central longitudinal axis of the through hole 18 and are orthogonal to a projection containing the central longitudinal axis of the through hole 18 and the central longitudinal axis of each of a recess 20 Central longitudinal axis of the passage opening 18. The three recesses 20 are thus arranged in one and the same cross-sectional plane of the Gleitkörperkäfigs 16. An angle M ⁰ is 30 ° in the embodiment shown.

FIGS. 4 to 6 show a second exemplary embodiment of a sliding body cage 16 'whose basic construction corresponds to the sliding body cage 16. In contrast to the sliding body cage 16, however, the sliding body cage 16 'has two superposed planes, each with three recesses 20, wherein the recesses 20 of one cross-sectional plane are offset from the recesses 20 of the other cross-sectional plane in the circumferential direction so that all six recesses 20 are evenly distributed around the circumference of the Gleitkörperkäfigs 16 'together.

Each recess 20 is provided for receiving a here circular cylindrical slider 22o whose outer diameter matches up to usual tolerances with the diameter of the recess 20, so that completely fills the cross section of the recess 20. FIGS. 7 and 8 show views corresponding to FIGS. 5 and 6, in which a sliding body 22 designed as described above is arranged in each recess 20. As can be seen in particular from FIG. 7, due to the described arrangement of the recesses 20, each sliding body 22 projects with its lateral surface into the cross section of the passage opening 18. In this way, the anchor rod 12, whose outer diameter almost corresponds to the diameter of the passage opening 18, held by the sliding bodies 22 by clamping.

Returning to FIG. 1, the further structure of the sliding anchor 10 will now be explained.

In order to allow the sliding anchor 10 to exert a stabilizing effect on a tunnel or tunnel wall, a load-transmitting armature plate 24 is provided, which is placed on the bore-input-side end of the anchor rod 12. The anchor plate 24, which is also usually made of steel and is generally square, but may also have a different shape, has in the middle a through hole through which a first protective tube 26 extends. The inner diameter of the protective tube 26 is greater than the outer diameter of the anchor rod 12, so that the protective tube 26 can surround the anchor rod 12 concentrically. In the exemplary embodiment shown, the protective tube 26 has substantially the same outer diameter as the sliding body cage 16, so that a uniform surface simplifying insertion into the bore results, but the outer diameter of the protective tube 26 can also be greater or smaller than the outer diameter of the sliding body cage 16.

At its free, protruding from the anchor plate 24 end of the protective tube 26 is provided with an external thread on which a mounting adapter 28 is screwed, which secures the protective tube 26 to the anchor plate 24. The mounting adapter 28 here has the shape of a hexagon nut, but can also be configured differently.

The first protective tube 26, which is fixed to the anchor plate 24 by means of the mounting adapter 28 designed as a hexagon nut, extends from the anchor plate 24 to the sliding body cage 16 (or 16 '), to which it is mounted in a force-transmitting manner. Such a force-transmitting attachment can be done for example by welding to the Gleitkörperkäfig 16, just as well, the inner end of the protective tube 26 but also have an internal thread which is screwed onto a matching, the Gleitkörperkäfig 16 existing external thread. According to a variant, not shown, the Gleitkörperkäfig 16 and the first protective tube 26 may also be integrally formed with each other. The first protective tube 26, which preferably consists of steel or plastic, thus provides a force transmitting connection between the Gleitkörperkäfig 16 (or 16 ') and the anchor plate 24 ago.

At the free end of the anchor rod 12 projecting from the anchor plate 24, a cylindrical stop member 30 is fixed, the outer diameter is selected so that it is smaller than the inner diameter of the first protective tube 26 so that the stop member 30 fits into the protective tube 26, and on the other hand larger than the diameter of the passage opening 18 in the sliding body cage 16 or 16 '. In the embodiment shown in Figure 1, the free end of the anchor rod 12 has an external thread on which the stop element 30 is screwed by means of a matching internal thread formed in it. Further, in the illustrated embodiment, an outer end surface 32 of the stopper member 30 is flush with a peripheral edge 34 of the mounting adapter 28 surrounding this end surface when the slide anchor 10 is set (i.e., in an initial state of the slide anchor).

The tip of the slide anchor 10 forms a mixing and anchoring element 36 with a plurality of mixing blades 38 fastened to the bore-side end of the anchor rod 12, which firstly serves for the use of conventional two-component adhesives used for setting rock bolts, which are inserted into the bore before setting an anchor. to mix intimately with each other. For this purpose, the anchor rod 12 is rotated after insertion into the bore, whereby the mixing element 36 is rotated. On the other hand, the mixing and anchoring element 36 is based on the curing of the adhesive or mortar on the latter from, in order to prevent in this way pulling out of the armature 10 from the bore.

In the exemplary embodiment shown, a second protective tube 40, which can be made of metal or plastic, extends from the sliding control element 14 to the mixing element 36. This second protective tube 40 holds the mass (mortar, adhesive) away from the surface of the anchor rod 12. with which the sliding anchor 10 is permanently anchored in the bore, not shown, and protects the other the anchor rod 12 against unwanted clamping or crushing loads that arise, for example, due to shifting rock plates and the anchor rod 12 can overload locally. The outer diameter of the second, the anchor rod 12 concentrically surrounding the protective tube 40 is here selected smaller than the outer diameter of the first protective tube 26, so that from the introduced into the bore adhesive or mortar, which upon insertion of the armature 10 in the Bore is displaced by the mixing and anchoring element 36 in a desired manner at least partially in an area behind the element 36, a substantially hollow cylindrical adhesive or mortar plug can form, the element 36 facing end face is as large as possible to a good load-bearing Support for 5 to provide the element 36. However, the outer diameter of the second protective tube 40 may be selected to be larger than illustrated, depending on the intended use of the sliding anchor 10.

FIG. 9 shows a second exemplary embodiment of a sliding anchor 10 in which the sliding control element 14, more precisely its sliding body cage 16 (or 16 '), is directly connected to the mounting adapter 28. The sliding control element 14 is therefore not relatively deep in the bore, in which the sliding anchor 10 is introduced in this embodiment, but in the region of the bore mouth. The passage recess in the armature plate 24 accordingly has a diameter which corresponds to the outer diameter of the sliding body cage 16 or 16 'except for customary tolerances. The first protective tube 26 is omitted in this embodiment or is present in any case in a greatly shortened form. Instead of a short first protective tube 26 and the mounting adapter 28 may have a short neck which connects to the Gleitkörperkäfig 16 or 16 ', or may be integral with the Gleitk body cage executed.

In the second embodiment, an end portion of the anchor rod 12 protrudes through the mounting adapter 28 to the outside and is provided with color markers, whose function will be explained later in more detail. A first, the assembly-5 adapter 28 adjacent portion 42 of the protruding end portion is colored green here, an adjoining second region 44 yellow and a free end of the anchor rod 12 comprehensive third region 46 red. Instead of the color markings, other markings may be provided, for example uniform graduation marks in the manner of a meter rule or the like. The remaining structure of the sliding o anchor 10 according to the second embodiment corresponds largely to that of the first embodiment, however, the stop member 30 is missing. Such can be attached to the free end of the protruding end portion of the anchor rod 12. 5 The function of the sliding anchor 10 will now be explained in more detail. After forming a mating bore, the slip anchor 10 is inserted into the bore and anchored there by means of mortars or adhesives known to those skilled in the art. alternatives tiv is the use of expandable elements for anchoring possible and known, for example, of expansion sleeves. The sliding anchor 10 shown is held in particular by a plug in the bore, which is formed by a material displacement of the adhesive or mortar used behind the mixing and anchoring element 36, ie on the side of the wellbore and after curing of the material pulling out of the anchor 10th prevented from the bore. After placing the anchor plate 24 and tightening the same by means of the mounting adapter 28, the sliding anchor 10 can then fulfill its load-bearing, stabilizing function.

About the slider 22, a clamping action is exerted on the anchor rod 12 and thus set a so-called breakaway force, which can transmit the sliding anchor 10 in the axial direction, without causing a relative movement between the anchor rod 12 and the sliding control 14. However, if this breakaway force is exceeded because, for example, due to rock movements or displacements of the armature plate 24 acting pressure is always greater, the sliding control member 14 can slide over the anchor rod 12 and thus by increasing the effective length of the sliding anchor 10 the compressive forces so far give in until they are again below the design breakaway force. Such a shift can of course take place in several sections and will only ever take place until the axial force acting on the sliding anchor 10 has dropped below the breakaway force again.

In the case of the first exemplary embodiment of the sliding anchor 10 shown in FIG. 1, the length, by which the sliding anchor 10 can yield to a maximum extent, is defined by the axial distance between the stop element 30 and the sliding body cage 16 or 16 '. If the sliding anchor of FIG. 1 yields due to increased load, the sliding body cage 16 or 16 'slips toward the stop element 30. If the sliding body cage 16 or 16 'abuts against the stop element 30, a further extension of the sliding anchor 10 is no longer possible. During the sliding operation, the stop element 30 moves from its first flush with the mounting adapter 28 position into the first protective tube 26 into it, which at a glance makes it possible to determine how far the sliding anchor has already yielded.

In the illustrated in Figure 9 second embodiment of the sliding anchor 10, the already used slide can be even easier "read", because the color marked areas 42, 44 and 46 disappear in a sliding of the armature 10 successively in the bore and it is only the protruding from the mounting adapter 28 part of the end portion to see. If, for example, the green area 42 has already completely disappeared, it can immediately be recognized from the yellow zone 44 which still protrudes that a considerable amount is already present

Rock movement must have taken place. This applies analogously if only the red region 46 can be recognized, which indicates that the sliding anchor 10 will soon have reached the limit of its lubricity.

Of course, the first embodiment shown in Figure 1 can be modified so that an end portion of the anchor rod 12 protrudes from the bore.

Claims

claims

A slide anchor (10) for insertion into a bore, comprising an anchor rod (12) on which is disposed a slide control member (14) having a through hole (18) through which the anchor rod (12) extends, the slide control member (14 ) comprises a Gleitkörperkäfig (16; 16 ') with at least one recess (20) for receiving a in contact with the lateral surface of the anchor rod (12) stationary slider (22), and an anchor plate (24) for abutment with the mouth of the

Bore surrounding area is determined when the sliding anchor (10) has been introduced into the bore, characterized in that the anchor plate (24) in force-transmitting connection with the Gleitkörperkäfig (16; 16 ') is.

2. Sliding anchor according to claim 1, characterized in that the Gleitkörperkäfig (16; 16 ') is part of a mounting adapter (28), which serves for fixing the anchor plate (24) against the area surrounding the mouth of the bore.

3. Sliding anchor according to claim 1 or 2, characterized in that the anchor rod (12) protrudes through the anchor plate (24) through out of the bore.

4. Sliding anchor according to claim 3, characterized in that the projecting out of the bore portion of the anchor rod (12) is provided with one or more markings indicating a still available slide.

5. Sliding anchor according to claim 4, characterized in that the markings are color markings, wherein one of the anchor plate (24) next region (42) of the anchor rod (12) green, an axially adjoining region (44) yellow and a subsequent, the free end of the anchor rod comprehensive area (46) is marked in red.

6. Sliding anchor according to claim 1, characterized in that a the anchor rod (12) concentrically surrounding Protective tube (26) extends from the anchor plate (24) towards the bore-side end of the anchor rod (12), one end of the protective tube (26) fixed to the slider cage (16; 16 ') and the other end to the anchor plate (24) is.

5 7. Sliding anchor according to claim 6, characterized in that the protective tube (26) by means of a mounting adapter (28) which is screwed onto the free end of the protective tube (26), on the anchor plate (24) is fixed.

Lo sliding anchor according to claim 6 or 7, characterized in that the mounting adapter (28) has a coaxial with the anchor rod (12) arranged Durchgangsausnehmung, and that on the free end of the anchor rod (12) or in the area thereof a stop element (30) is fixed, whose diameter is larger than the diameter of the through hole (18) i5 and which is in an initial state of the sliding anchor in the through-hole.

9. Sliding anchor according to claim 8, characterized in that an outer end face (32) of the stop element 20 (30) in the initial state of the sliding anchor is flush with an end face (32) surrounding the outer edge (34) of the mounting adapter (28).

10. Sliding anchor according to claim 8, characterized in that the anchor rod (12) or an extension of the same 5 protrudes from the mounting adapter (28) and is preferably provided there with one or more markings indicating a still available sliding section.

11. Sliding anchor according to claim 10, characterized in that the markings are color markings, wherein one of the anchor plate (24) next region of the anchor rod (12) or its extension green, an axially adjacent thereto yellow area and a subsequent, the free End of the anchor rod or its extension is marked in red area. 5

12. Sliding anchor according to one of claims 6 to 9, characterized in that a Gleitstreckenerfassungselement in the region of free end of the anchor rod (12) is fixed, in particular a band, a wire, a thread or the like.

13. Sliding anchor according to one of claims 2 to 5 or 7 to 12,

5 characterized in that at the bore-side end of the anchor rod (12) a mixing and anchoring element (36) is fixed and that the mounting adapter (28) is formed at its free end for coupling with a mounting device, the mounting adapter (28) and thus the sliding body cage (16; 16 '), the anchor rod (12) and the mixing and anchoring element (36) rotates during insertion of the lo sliding anchor in the bore.

14. Sliding anchor according to one of the preceding claims, characterized in that

- Each recess (20) for receiving a slider (22) in the Gleitkörperkäfig i5 (16; 16 ') is arranged tangentially to the lateral surface of the anchor rod (12),

- The Mantelhüllfläche each recess (20) projects a predefined measure in the free cross section of the through hole (18), and

- Each slider (22) fills the cross section of the associated recess (20).

20

15. Sliding anchor according to one of the preceding claims, characterized in that in the Gleitkörperkäfig (16; 16 ') a plurality of recesses (20) around the circumference of the anchor rod (12) around are arranged in particular evenly distributed. 5

16. Sliding anchor according to claim 15, characterized in that a plurality of recesses (20) in a cross-sectional plane of the Gleitkörperkäfigs (16) are arranged. 0

17. Sliding anchor according to one of claims 15 or 16, characterized in that the plurality of recesses (20) in groups in different cross-sectional planes of the Gleitkörperkäfigs (16 ¹ ) are arranged.

18. Sliding anchor according to one of the preceding claims, 5 characterized in that each sliding body (22) is conical, in particular conical roller-shaped.

19. Sliding anchor according to one of the preceding claims, characterized in that the lateral surface of each slider (22) is cambered.

20. Sliding anchor according to one of claims 1 to 17, characterized in that each sliding body (22) is cylindrical, in particular roll-shaped.