Geotechnical anchor with swelling body, anchoring system and production of the anchoring system

Abstract

A geotechnical anchor (4) for anchoring components (2) in the soil or rock (3) is proposed. The task is to propose a geotechnical anchor with a significantly improved environmental footprint, particularly with regard to a reduction in CO2 emissions.The problem is solved with a geotechnical anchor comprising at least one tension element (7) with an axial orientation, at least two plate elements (9) fixed at intervals in the axial orientation on the at least one tension element, which extend around the tension element, and at least one hydrophilic swelling body (5) between the plate elements, wherein the at least one swelling body extends around the at least one tension element, completely fills the space between the plate elements and has solid contact with all the respective bounding plate elements, and the at least one swelling body consists of or comprises at least one element of swelling material.

Description

[0001] The invention relates to a geotechnical anchor with at least one swelling body as a force introduction body for anchoring tensile components in the earth or rock according to the first patent claim. Furthermore, the invention relates to an anchor system with the geotechnical anchor and the production of this anchor system according to claims 14 and 15, respectively.

[0002] Geotechnical anchors and anchor systems of the type mentioned above are used for the back-anchoring of geotechnical structures or for the introduction of tensile forces into the subsoil. They are used to fix, anchor, or secure structures or components (e.g., retaining walls, excavation bases or supports, but also permanent structures such as anchor walls, retaining walls, rock supports, bridge bearings, slope stabilization, tunnel linings, dams, piers, cable car anchors, fixations against uplift and underwater currents, etc.) to a geological subsoil such as the aforementioned soil or bedrock. They comprise, on the one hand, an anchorage in the aforementioned subsoil and, on the other hand, a tension element connected to the anchorage extending from the subsoil, with which the aforementioned structure or component can be connected to the anchorage on or above the subsoil.Preferably, the tension element is subjected to a tensile stress which is transferred from the anchorage into the subsoil.

[0003] This tensile stress is transferred via the tension element to the structure (or component) to be anchored, serving to connect and fix it in a predetermined position relative to the substructure. Tensile elements are typically formed by rod elements or cable elements, e.g., strands, preferably made of steel.

[0004] Conventional geotechnical anchors and anchor systems are usually designed as so-called grouted anchors, where anchoring is ensured by a grout body.

[0005] The three main components of a grout anchor are the aforementioned tension element, the anchor head, and the cement-based grout body as anchorage and force introduction body, with the tension element connecting the grout body to the anchor head. After the cement-bound grout body has hardened, tensile forces can be introduced into the subsoil. The free anchor length of the tension element determines the length of the grout anchor and thus the area and depth of force introduction in the ground. The tensile forces are introduced into the subsoil via shear stresses in the area of ​​the grout body (anchorage). The axial course of the shear stress transfer via the grout body differs depending on the anchor system (e.g. composite anchor, pressure pipe anchor, temporary or permanent anchor). Furthermore, grout anchors must be designed to ensure anchorage in the subsoil with sufficient safety over their entire service life.The load-bearing behavior of the anchors can be tested using tensile tests.

[0006] After the borehole has been created (with or without support), the tension element, usually made of steel or GRP, is inserted. The grout body is then constructed. The borehole is grouted with cement paste (cementitious material, cement, or concrete), and the casing, if present, is pulled. The free anchor length around the tension element between the anchor head and the grout body is created by flushing out excess cement paste. This ensures that no shear force is transferred in the area of ​​the tension element. Once the grout body has hardened, the system is load-bearing. To activate its load-bearing capacity, the tension element is prestressed via the anchor head.

[0007] A disadvantage of conventional anchor systems with grouted anchors is the high demand for cement, the production of which releases correspondingly high emissions of greenhouse gases such as CO2. CO2 is produced by the burning of cement clinker, a process in which CO2 is driven off the starting material calcium carbonate using energy. The high cement consumption is one of the reasons why the construction industry is one of the industries with the highest CO2 emissions (estimated at between 25% and 40%). For example, even in a 2 km long tunnel construction site using the open cut method, up to 5,000 anchor systems are installed. Assuming a grouting length of 5 m in the borehole, this results in a required volume of approx. 0.16 m3 of cement-based grouting material per anchor system. For the construction project described, the cement suspension requirement therefore amounts to 800 m3. This corresponds approximately to a cement requirement of 500 t.

[0008] The installation of anchors with grouted anchors also requires a relatively large amount of component setup on site, since in addition to the creation of the anchor borehole, anchor grouting work must also be carried out.

[0009] Based on this, there is a Object of the invention to propose a geotechnical anchor with a significantly improved environmental balance, particularly with regard to a reduction in CO2 emissions, which in particular does not require the use of cement-containing materials in the anchoring process.

[0010] A further object of the invention is to propose a geotechnical anchor and an anchor system which can be applied on site at the borehole with the least possible handling effort.

[0011] A further object of the invention is to propose a method for producing an anchor system with the lowest possible probability of error.

[0012] The problem is solved with a geotechnical anchor, an anchor system, and a method for producing the anchor system having the features of claims 1, 14, and 15, respectively. These dependent claims reflect advantageous embodiments and refinements of this solution.

[0013] To solve the task, a geotechnical anchorfor anchoring components in the earth and / or rock. This comprises at least one, preferably one tension element with an axial alignment, at least two plate elements fixed on the tension element at a distance from one another in the axial alignment, which extend around the at least one tension element, and at least one swelling body between the plate elements as a force introduction body between the anchor and the earth and / or rock. The at least one swelling body extends around the at least one tension element, specifically between two plate elements. The space between the plate elements is completely filled by at least one swelling body, i.e. optionally also by a serial arrangement of several swelling bodies; the swelling body or bodies have solid contact with all of the respectively delimiting plate elements.

[0014] The expansion elements themselves are preferably industrially prefabricated prefabricated elements with customizable dimensions and / or material properties (especially swelling capacity, rheological properties, shear strength, water permeability, stiffness), which are fixed to at least one of the tension elements, either individually or in series, with identical or different material properties, depending on the application requirements. Uniform dimensions advantageously simplify the setup effort (modularization, modular system) for flexible production of the proposed geotechnical anchor depending on the application. Within this framework, customizable dimensions of the anchor tension elements and expansion elements are also proposed, the dimensions and diameters of which are based on common or established borehole sizes.

[0015] A tension element is preferably formed, at least in sections, by a rectilinear tension rod or a rectilinear tension profile (e.g., a hollow profile such as tubes, star or double-T profiles, preferably point-symmetrical about an axially oriented axis of symmetry). In the area of ​​the plate elements, this has a thread, shoulders, or bayonet lock for receiving and axially fixing the plate elements. Preferably, the at least two plate elements fixed to the tension element in the axial alignment extend orthogonally to the axial alignment.

[0016] Alternative designs of the tension element consist of wire strands, one or more wire ropes, bundles of bars (multi-bar anchors) or profiles.

[0017] A basic design of the geotechnical anchor comprises a swelling body which is axially limited on both sides by a plate element on a tension element.

[0018] One embodiment, however, provides for at least two expansion bodies arranged axially in series on the tension element. They form a series of expansion bodies, each of which is axially terminated by a plate element. In the following, the embodiments and configurations of a expansion body (stated in the singular) generally also refer, without further reference, to multiple expansion bodies in the anchor or to the individual expansion bodies in a series of expansion bodies.

[0019] The preferred embodiment provides at least partially axially fixed plate elements as intermediate elements between the swelling bodies.

[0020] A further embodiment provides two spaced-apart plate elements between each swelling body, which are preferably fixed to a tension element to space the swelling bodies apart. The geotechnical anchor thus allows for more than one continuous anchoring area; existing cavities in the anchoring area that would not contribute to anchoring could thus be bridged.

[0021] Another embodiment envisions the use of several tension elements arranged in parallel but axially displaceable relative to one another. Each of these tension elements leads to a source body or group of source bodies that are framed and fixed to them at least axially by plate elements. This allows several areas in the borehole to be independently provided for force introduction and to be individually controlled via one of the tension elements.

[0022] The cross-section of a swelling body and the plate elements is preferably identical within the usual manufacturing tolerances; the plate elements and the at least one swelling body of a geotechnical anchor have a common cross-section around the tension element when viewed in axial alignment. Plate elements and swelling bodies also preferably extend rotationally symmetrically around the tension element to which they are fixed.

[0023] A preferred design for the panel elements is to be water-permeable (e.g., open-pored) or water-conducting (e.g., via water channels or pipes). This allows additional water access through the panel elements to the adjacent spring bodies, which in turn can be used to control the swelling process.

[0024] Within the scope of the application, the proposed swelling bodies are characterized by their hydrophilicity and their ability to increase their volume upon absorption of water. The swelling body(ies) consists of or comprises a swelling material, preferably consisting of the clay mineral montmorillonite with the chemical composition (Na,Ca) 0.3 (Al,Mg) 2 Si 4 O 10 (OH) 2 ·nH 2 O or with significant components of montmorillonite such as bentonite. If this volumetric deformation is impeded, e.g., by walls in a borehole, a so-called swelling pressure builds up in these areas.

[0025] Consequently, a preferential use of a natural clay compact as a swelling body is proposed as a structural element for the introduction of force into the subsoil, whereby the technical use of the swelling capacity of a swellable material in the swelling body is an essential feature.

[0026] Alternative designs include swelling bodies made of wood or swelling polymers.

[0027] In an optional embodiment, each swelling body either consists of at least one element made of swellable material or comprises one of these elements. This also includes additional elements made of non-swellable materials.

[0028] The proposed swelling body overcomes the problem of increased CO2 emissions by significantly reducing the amount of cement clinker required for the production of geotechnical anchors. By using a natural and swellable material, preferably clay, cement production for the anchoring is no longer required, thus significantly reducing CO2 emissions during anchoring. Furthermore, natural clay minerals remain in the soil or bedrock when the anchor is removed or dismantled, which is advantageous.

[0029] A particular advantage of the proposed expansion bodies is that they are preferably integrated into the geotechnical anchor as components during its manufacture or assembly. The expansion bodies can be mass-produced, for example, as prefabricated components formed into a final contour, preferably with a predeterminable expansion state (moisture level), dimensions, and / or tolerance ranges.

[0030] In this context, industrial pre-assembly of geotechnical anchors with uniform diameters (or cross-sections) is proposed away from the application site, preferably in a dry assembly hall, which then only need to be inserted on site into boreholes in the ground with an adapted diameter (anchor diameter plus a fit). The manufacture and pre-assembly of the anchors is advantageously possible in a controllable or adjustable atmosphere, i.e. with a pre-determined temperature and humidity. Furthermore, the anchor can be packaged in this atmosphere and thus transported to the application site in a protected manner. Unpacking preferably takes place immediately before application, thus keeping the time interval during which the geotechnical anchor with the swelling bodies comes into contact with the possibly humid atmosphere present at the borehole before insertion into a borehole as short as possible.Furthermore, prefabrication of the swelling bodies as prefabricated compacts and their pre-assembly into a geotechnical anchor results in a significant reduction in construction time and reduced noise and dust emissions.

[0031] Preferably, the at least one swelling body is unencapsulated, at least externally unencapsulated, as part of the geotechnical anchor. It is thus accessible to groundwater or moisture, thus allowing for swelling. Unencapsulated in this context does not exclude components adjacent to the swelling body, thus locally encapsulating it, in particular the aforementioned plate and tension elements.

[0032] If, as part of an optional design, at least one swelling body is expressly unencapsulated only radially outward (i.e., encapsulated or covered on the outer surface, but encapsulated or covered in the other areas), the access and entry of moisture occurs only selectively through the unencapsulated areas, i.e., swelling initially occurs only locally in these areas. However, disruption or cracking caused by the swelling facilitates or accelerates the penetration or infiltration of moisture into the volume of the swelling body, which then swells with a time delay.

[0033] However, in order to reduce or eliminate the risk of undesired deformation of the swelling bodies due to moisture prior to anchor production and / or application, a preferred embodiment proposes at least temporary encasing or encapsulation of the swelling body prior to application of the geotechnical anchor in a borehole, e.g. in soil or rock, to form an anchor system.

[0034] In a first preferred embodiment, the sheathing or encapsulation of a swelling body is provided by a water-impermeable and preferably also water-resistant film, e.g. made of plastic, which is inserted into the geotechnical anchor together with the swelling body and is only opened when the anchor is positioned in the borehole and is preferably removed, e.g. pulled off, entirely or at least in those areas of the swelling body facing outwards and / or towards a water supply. The film can be removed from the anchor in the borehole, for example, by a pull rope, which is preferably attached to the film at a weak point and allows the film to be torn open at this point.

[0035] In a further preferred embodiment, the encapsulation or encapsulation of a swelling body is realized by a continuous, but water-soluble or swelling-retardant coating made of a water-soluble plastic such as polyvinyl alcohol or sugar. The coating preferably dissolves in the borehole in the prevailing humidity there, thus only allowing the swelling body to access moisture with a delay. As long as the layer remains continuous due to dissolution, it represents a barrier to water or moisture.

[0036] Preferably, the swelling body, in a dry state—i.e., after production and before the initial absorption of water or moisture thereafter—and the plate elements together have a cylindrical shape, with the two round boundary surfaces of the shape being formed by two plate elements. When the anchor is inserted into a borehole as a cavity, the resulting cylindrical outer surface forms the counter surface to the generally cylindrical borehole inner wall. This enables a uniform and rotationally symmetrical radially outward-directed swelling capacity until the radially limiting borehole inner wall is reached.By axially limiting the swelling bodies by the plate elements, they are axially limited in their expansion, thus also generating an axial swelling pressure, which in turn causes the volume increase due to swelling to be redirected radially outward and the maximum possible radial expansion to be advantageously increased. The swelling bodies and plate elements are arranged around the tension element, which also determines the spacing of the plate elements around the swelling bodies. Together with the tension element, they preferably completely fill the cylindrical shape, which in turn significantly reduces the undesirable absorption of portions of the aforementioned volume increase due to swelling into potentially remaining cavities in the cylindrical shape.

[0037] A preferred embodiment of the geotechnical anchor provides a water supply line on or into the at least one swelling body, so that swelling is not initiated solely by ambient humidity. Within this context, the tension element is integrated as a further preferred embodiment. Either the supply line is integrated into the tension element, for example, as a separate and removable component (e.g., a hose), or the tension element itself is designed as a hollow profile that serves as a water supply line and has water-permeable walls (perforations, through openings, open porosity) in the area of ​​the at least one swelling body.Both of these designs are suitable for supplying water directly into the interior of the spring body. The introduction of water causes internal swelling and the tearing of still-dry peripheral areas, with the resulting cracks allowing water to enter the entire spring body volume in a very short time. This design is therefore suitable for anchor systems that require rapid application and load-bearing capacity, for example, for securing against incipient earth movements (slope stabilization, debris avalanches, flood protection, etc.). Furthermore, this design enables the anchor system to be used in earth and rock foundations without sufficient groundwater access and / or insufficient permeability of the subsoil from the outside to the spring body.

[0038] The solution to the task also includes a Anchor systemwith the aforementioned geotechnical anchor with a swelling body as previously proposed. The anchor system also includes a cavity (with at least one access opening for inserting the anchor) in the soil or rock, into which the geotechnical anchor with the swelling body is inserted. The swelling body is hydrophilic and experiences an increase in volume with the addition of water to the cavity. The anchoring, and thus the anchor system, is created when the swollen swelling body touches the walls in the cavity and, upon further water absorption, has built up a swelling pressure in the aforementioned manner.

[0039] The cavity is preferably formed by a borehole into which the geotechnical anchor with the expansion body is inserted. It is particularly advantageous if the cross-section of the expansion body (and preferably also of the plate elements) corresponds at most to that of the borehole, within the usual manufacturing tolerances, with the cross-sections being equal and round in axial alignment.

[0040] In principle, the anchor system is suitable for anchoring in bedrock (rock anchor, borehole predominantly in solid rock) and in subsoil (ground anchor, borehole predominantly in loose rock). In both cases, at least one swelling body of the geotechnical anchor swells radially outward against the inner wall of the cavity, whereby the resulting surface pressure between the swollen swelling body and the cavity is capable of transferring axial shear stresses from the anchor to the bedrock or subsoil.

[0041] The state of the art continues to distinguish between a temporary anchor (anchoring period of less than approximately two years) and a permanent anchor (anchoring period of more than approximately two years), which are characterized in particular by improved long-term corrosion protection.

[0042] Another embodiment of the anchor system is a so-called soil nailing system. A soil nail can also be composed of the aforementioned expanding elements. In contrast to the anchor system shown, a soil nailing system eliminates the free steel length. The shear force transmission must be ensured across the entire nail length.

[0043] One design for the expansion body is to be dimensioned so that it only needs to expand partially to completely fill the cavity to be filled, since expansion pressure only develops when the cavity is filled. Furthermore, any unswollen material should remain in the expansion body for the entire service life of the anchor. This provides additional safety reserves in the anchor system if necessary.

[0044] Furthermore, the solution to the task also includes a Production of the aforementioned anchor system. It includes the following procedural steps: Provision of an aforementioned geotechnical anchor, as proposed to achieve the object, preferably with a cylindrical outer surface of at least the swelling body. Preferably, the anchor does not have any extremities projecting outwards beyond the outer surface. The provided geotechnical anchor is preferably industrially prefabricated, i.e. it does not have to be assembled on site at the borehole, which in turn not only reduces the manufacturing tolerances, but also advantageously considerably expands the possibilities for quality control. In particular, industrial production enables the production of the hydrophilic swelling bodies and their integration into a geotechnical anchor in an adjustable and reproducible atmosphere and environment with considerably smaller manufacturing tolerances. Provision or creation of a cavity in an earth or rock base, preferably as a borehole with a round cross-section.Insertion of the geotechnical anchor into the cavity, whereby the swelling body is enclosed within the cavity. Exposure to moisture or water of the swelling body causes the swelling body to swell up to the inner wall of the cavity and / or into the surrounding soil or bedrock. The swelling body is preferably dimensioned such that, when exposed to moisture, it only needs to swell partially to completely fill the surrounding borehole volume. In particular, in the event of possible ground movement around the borehole or in the surrounding soil and the associated expansions or changes in the borehole volume, such a swelling reserve can be filled by subsequent further swelling.

[0045] In the proposed geotechnical anchor and anchor system, the swelling body assumes essential functions of the cement-based grout body of a conventional anchor system. The cylindrically manufactured swelling body preferably consists of a naturally occurring and swellable clay mineral (preferably consisting of or containing montmorillonite). Instead of a cement grout body, the tensioning of the tension element in the subsoil or soil is achieved by the swelling of the swelling body and the associated outward pressure development. The swelling is activated by the contact of the aforementioned clay mineral in the swelling body with water. The required water can be provided, for example, by adjacent groundwater, slope water, or additional water.

[0046] In summary, a conventional cement-bonded grout body of an anchor is essentially replaced by a prefabricated expansion body made of swellable material (e.g., a highly compacted mineral mixture). Contact of the swellable material with water causes an increase in volume (swelling process). The soil and / or rock at the borehole prevents this free increase in volume, resulting in the buildup of swelling pressure. This pressure in the area of ​​the expansion body leads to a tension effect with the surrounding soil and / or rock, whereby tensile forces are transferred from the tension element into the soil and / or rock.The water required for expansion can reach the expansion body either through existing water in the soil and / or bedrock or through active water supply. The main advantage of the expansion anchor compared to conventional anchor systems is the elimination of cement and the associated significant reduction in CO2 emissions. In addition, lower noise levels during installation, reduced site setup requirements, and a shortened construction time can be expected. The use of prefabricated expansion bodies also makes anchor systems with variable load introduction lengths possible.

[0047] The use of one or more of the described expansion bodies in a proposed geotechnical anchor or anchor system is also proposed. The expansion body enables the anchor to be anchored in the soil or earth without cement. At the same time, its use also significantly reduces the requirements, effort, and setup times at the borehole on site in the aforementioned manner. This not only reduces CO2 emissions but also shortens construction times and minimizes costs.

[0048] The invention is explained in more detail with reference to the following exemplary embodiments, the following figures, and the descriptions. All features and their combinations are not limited to these exemplary embodiments and their configurations. Rather, they should be considered representative of other possible configurations that are not explicitly shown as exemplary embodiments. They show: Fig.1a schematic sectional view of an anchor system with a geotechnical anchor with its basic components for anchoring components in the soil or rock, Fig.2a and b schematic sectional views of further embodiments with several swelling bodies on a tension element, Fig.3 a schematic sectional view of another embodiment of an anchor system with a geotechnical anchor according to Fig.1 , but additionally with a water supply line into the source body, Fig.4 a schematic sectional view of another embodiment of an anchor system for anchoring in a borehole with a subsoil discontinuity and two swelling body rows (serial arrangement of swelling bodies in the anchor), which are connected to the same tension element, Fig.5a schematic sectional view of another embodiment of an anchor system with a geotechnical anchor with two tension elements, each with a row of swelling bodies, Fig.6a to c three steps of manufacturing an anchor system according to Fig.1 in schematic sectional views.

[0049] An anchor system 1 for anchoring components 2 in the earth or rock 3 as proposed includes a geotechnical anchor 4 with a source body 5 in a borehole 6 as a cavity in the earth or rock 3 - cf. Fig.1 . The swelling body itself is hydrophilic and, during anchoring, is in a partially or completely swollen state due to the supply of water; it consists of or comprises at least one element made of a swellable material.

[0050] The geotechnical anchor 4 has a tension element7 with an axial alignment in the borehole 6 It connects the anchoring between the source body 5 and surrounding soil and rock 2 in the borehole with the component to be anchored 2 at the borehole opening 8. On the tension element, the Fig.1 The embodiment shown has two plate elements fixed on the tension element in axial alignment 9, which extend around the tension element, as well as the said hydrophilic swelling body 5 between the plate elements. The swelling body extends around the tension element, completely filling the space between the plate elements and thereby maintaining solid contact with all the respective bordering plate elements 9This limits the swelling body axially during swelling by the rigidly spaced plate elements, and directs the swelling radially outward. The axial length of the swelling body forms the load introduction length of the geotechnical anchor in the borehole.

[0051] Fig.2a and b represent further embodiments of a geotechnical anchor with multiple expansion bodies on a tension element. The expansion bodies can optionally be separated from each other using plate elements.

[0052] Fig.2a shows a design that differs from the one in Fig.1 shown design only in that one source body is formed by a series of source bodies 10, ie several serial around the tension element 6 arranged and directly adjacent source bodies 5 The swelling body array is axially supported on both sides by two plate elements 9completed. Such a design particularly favors the use of standard elements as expansion bodies, but also their flexible adaptation to a specific anchoring task and environment simply by adding, removing, or replacing expansion bodies. Furthermore, this design also enables the use of different expansion bodies in a single expansion body array. The axial length of the expansion body array forms the load introduction length of the geotechnical anchor in the borehole.

[0053] Fig.2b shows a design that differs from the one in Fig.2a shown design in that additionally between the axially arranged swelling bodies 5 one plate element each 9 as an intermediate element 11This not only prevents direct contact between adjacent swelling bodies, but also additionally guides the swelling in a radial direction against the borehole's inner wall. The axial length of the swelling bodies, including the intermediate elements, forms the load introduction length of the geotechnical anchor in the borehole.

[0054] Fig.3 shows an example of an anchor system with a geotechnical anchor according to Fig.1 , but additionally with a water supply line 12 from a schematically shown water source 13 into the borehole and along the tension element into the source body. A separate water supply line is shown, running parallel to the tension element. 12, through the proximal plate element 9 through into the source body. The outlet 14In the illustrated embodiment, it is located in the form of a pipe end in the source body at a point inside the source body. Alternative outlets provide for several water outlets, for example via - not in Fig.3 shown - several discrete lateral outlet openings or an open porosity in the water supply line section in the source body (advantage: larger source body area can be watered simultaneously). Also not in Fig.3 Explicitly shown are designs in which the water supply line is integrated in the tension element (advantage: better line routing) and / or the tension element comprises a hollow profile as a water supply line (advantage: no separate line, but also not removable from the anchor system).

[0055] Fig.4 represents another embodiment of an anchor system with a geotechnical anchor, which is particularly suitable for anchoring in a borehole 6with a subsoil discontinuity 15 Subsoil discontinuity in this context is cracks or material transitions in the soil and rock 3, the borehole 6 There will be a two- or multi-division of the load introduction length, with the subsoil discontinuities falling on the interruptions of the load introduction length. A serial arrangement of source bodies shown in Fig. 3a and b 5 and these delimiting plate elements 9 including optional intermediate elements 11 is divided into several source body arrays in this embodiment.

[0056] Fig.5 shows schematically another embodiment of an anchor system with a geotechnical anchor with two tension elements 16, 17, each with its own row of source bodies 5 and panel elements 9 The tension element 17is preferably axially displaceable in the arrangement on the tension element 16 guided, preferably to avoid jamming during swelling in at least one passage opening, preferably in a pipe inserted therein.

[0057] Fig.6a to c represents three steps of manufacturing an anchor system as an example. Fig.1 . After the provision of a geotechnical anchor, the next step is the provision or creation of a borehole 6 as a cavity in a soil or rock 3 -

[0058] Fig.6a . This is followed by the installation of the geotechnical anchor 4 into the borehole, whereby at least the not yet swollen swelling body 5 from the borehole wall forming a clearance fit 18 is enclosed - Fig.6b .The swelling body is then exposed to moisture or water, causing it to swell up to the inner wall of the borehole and / or into the surrounding soil or rock. This creates a load introduction area. 19 by pressure between the borehole inner wall and the source body - Fig.6c . This creates a shear connection that can be further reinforced, for example, by means of mechanical barbs in the swelling body. List of reference symbols:

[0059] 1Anchor system 2Component 3Soil or bedrock 4Geotechnical anchor 5Source body 6Borehole 7Tension element 8Borehole opening 9Plate element 10Source body array 11Intermediate element 12Water supply line 13Water source 14Outlet 15Subsoil discontinuity 16First tension element 17Second tension element 18Clearance fit 19Load introduction area

Claims

1. Geotechnical anchor (4) for anchoring components (2) in the earth or rock (3), comprising a) At least one tension element (7, 16, 17) with an axial alignment, b) at least two plate elements fixed on the at least one tension element in the axial alignment at a distance (9), which extend around the tension element, and c) at least one hydrophilic swelling body (5) between the plate elements, wherein d) the at least one swelling body extends around the at least one tension element, completely fills the space between the plate elements and thereby has solid contact with all respectively delimiting plate elements and e) the at least one swelling body, which consists of at least one element made of swellable material or comprises such elements.

2. Geotechnical anchor (4) according to claim 1, characterized in that at least one tension element (7, 16, 17)at least partially formed by a straight tension rod or a straight tension profile, which in the area of ​​the plate elements (9) has a thread, steps or bayonet lock for its reception and axial fixation.

3. Geotechnical anchor (4) according to claim 1 or 2, characterized in that the plate elements (9) and source bodies (5) extend rotationally symmetrically around the at least one tension element.

4. Geotechnical anchor (4) according to one of the preceding claims, characterized in that the plate elements (9) and at least one source body (5) viewed in axial alignment have a common cross-section around the at least one tension element.

5. Geotechnical anchor (4) according to one of the preceding claims, characterized in that the source body (5) in a dry state and the plate elements (9)together have a cylindrical shape and completely fill this together with the at least one tension element, wherein the two round boundary surfaces of the shape are formed by two plate elements.

6. Geotechnical anchor (4) according to one of the preceding claims, characterized in that at least one source body (5) or consists of or contains swellable material, preferably the clay mineral montmorillonite and / or is unencapsulated to the outside and thus accessible to groundwater or moisture.

7. Geotechnical anchor (4) according to one of the preceding claims, characterized in that at least one of the source bodies (5) a water-soluble or swelling-retardant coating made of a water-soluble substance, preferably plastic or sugar.

8. Geotechnical anchor (4) according to one of the preceding claims, characterized in that a water supply line (12)on or in the at least one source body, wherein the water supply line (12) preferably is integrated into the at least one tension element or the at least one tension element comprises a hollow profile as a water supply line.

9. Geotechnical anchor (4) according to one of the preceding claims, characterized in that the plate elements (9) have water-permeable or water-conducting properties.

10. Geotechnical anchor (4) according to one of the preceding claims, characterized in that at least two source bodies (5) are arranged axially serially on the at least one tension element and form a swelling body array (10) form, wherein preferably the at least two swelling bodies (5) are formed by shaped bodies with different material properties and / or uniform dimensions.

11. Geotechnical anchor (4) according to claim 9 or 10, characterized in thatbetween two source bodies (4) a plate element (9) or two plate elements spaced apart from one another are provided, wherein the plate elements are preferably fixed axially to the tension element between two swelling bodies.

12. Geotechnical anchor (4) according to one of the preceding claims, characterized in that two or more tension elements (16, 17) which are arranged parallel to each other but axially displaceable against each other, with at least one swelling body being attached to each of these tension elements (5) or a source body array (10), are fixed axially framed by plate elements.

13. Geotechnical anchor (4) according to claim 12, characterized in that at least one of the tension elements (16, 17) in at least one axial passage opening or a pipe inserted therein through the swelling body or the swelling body arrangement on at least one other of the tension elements.

14. Anchor system (1), comprising a geotechnical anchor (4) with at least one source body (5) according to one of the preceding claims in a cavity (6) in a soil or rock (3), characterized in that the swelling body is hydrophilic and is in a partially or completely swollen state due to the addition of water.

15. Manufacturing an anchor system (1) according to claim 14, comprising the following method steps: a) providing a geotechnical anchor (4) according to one of claims 1 to 19, b) providing or creating a cavity (6) in a soil or rock (3), c) Insertion of the geotechnical anchor into the cavity, whereby at least one swelling body (5)is enclosed by the cavity and d) subjecting the at least one swelling body to moisture or water, whereby the swelling body swells up to the inner wall of the cavity and / or into the surrounding earth or rock.

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