Application method of novel yielding anchor rod

Abstract

The invention discloses an application method of a novel yielding anchor rod. The application method comprises the following steps that the yielding anchor rod is manufactured; the yielding anchor rod comprises an outer sleeve and an inner sleeve; the inner sleeve is arranged in the outer sleeve; a lug boss is arranged on the outer wall surface of the inner sleeve; a first opening is formed in the wall face of the outer sleeve, and the protruding part is arranged in the first opening in a penetrating mode. The axial length of the first opening is larger than the axial length of the outer wall face, provided with the protruding part, of the inner sleeve. Drilling and cleaning the interior of a hole; a cement cartridge is mounted at the tail end of the outer sleeve; pushing the yielding anchor rod into the drill hole until the yielding anchor rod reaches a designed position; a grouting pipe is inserted from the inner sleeve for grouting, and the protruding part is jacked into the surrounding rock for anchoring through grouting pressure; a connecting mechanism is installed at the head end of the outer sleeve, and the yielding anchor rod is fixed to surrounding rock. According to the application method of the novel yielding anchor rod, prestress and anchoring performance are provided, the yielding anchor rod can slide to yield, and pressure is released in time.

Description

Technical Field

[0001] The present invention relates to the field of anchor support technology, and in particular to an application method of a novel pressure-yielding anchor. Background Art

[0002] When constructing tunnels in high-stress areas, large deformation of the surrounding rock will cause the anchor rods to bear excessive deformation pressure, greatly increasing the risk of anchor rod failure. The most effective solution at present is that the anchor rods must have the corresponding deformation capacity to deform synchronously with the surrounding rock while maintaining high resistance, thereby releasing part of the deformation pressure of the surrounding rock. Therefore, the strength of the anchor rod, its own resistance and its "pressure relief" functionality are extremely important for controlling large deformation surrounding rocks.

[0003] "Pressure yielding" means using appropriate support measures to allow the surrounding rock to shrink to a certain extent, while keeping the anchor rod itself from being severely damaged, so as to release some energy and improve the stability and safety of the support structure. However, traditional anchor rods are usually designed to have high rigidity and strength to ensure that they can be firmly anchored in the rock and soil. However, this high-strength design makes it difficult for the anchor rod to produce sufficient deformation to absorb and release energy when subjected to large tensile forces, causing the anchor rod itself to fail, thereby limiting its ability to continuously suppress surrounding rock deformation and release surrounding rock energy, bringing great safety risks and economic challenges to construction. Therefore, there is an urgent need for an anchor rod with certain anchoring resistance and sliding pressure yielding characteristics to solve the current problem of support failure caused by surrounding rock extrusion deformation as soon as possible. Summary of the invention

[0004] In view of the deficiencies in the prior art, one purpose of this specification is to provide an application method of a new type of pressure-releasing anchor rod, which not only provides prestressing and anchoring performance, but also allows the pressure-releasing anchor rod to slide and release pressure in time.

[0005] To achieve the above purpose, the present specification provides a novel application method of a pressure-yielding anchor rod, comprising the following steps:

[0006] A yield anchor is manufactured; the yield anchor comprises an outer sleeve and an inner sleeve; the inner sleeve is arranged in the outer sleeve; a protrusion is arranged on the outer wall of the inner sleeve; a first opening is arranged on the wall of the outer sleeve, and the protrusion is passed through the first opening; the axial length of the first opening is greater than the axial length of the outer wall of the inner sleeve on which the protrusion is arranged;

[0007] Drilling and cleaning holes;

[0008] Installing a cement roll at the rear end of the outer sleeve;

[0009] Pushing the yield anchor rod into the borehole until it reaches the designed position;

[0010] Inserting a grouting pipe from the inner sleeve to perform grouting, and pushing the raised portion into the surrounding rock for anchoring by the grouting pressure;

[0011] A connecting mechanism is installed at the head end of the outer sleeve to fix the pressure anchor rod to the surrounding rock.

[0012] As a preferred embodiment, in the step of making the yield anchor rod, the resistance calculation formula of the yield anchor rod is:

[0013]

[0014] Among them, F k is the resistance of the yield anchor; τ is the shear strength of the surrounding rock; L c is the length of the protrusion; μ is the friction coefficient between the protrusion and the surrounding rock; σ s is the compressive strength of the surrounding rock; d c is the diameter of the protrusion.

[0015] As a preferred embodiment, in the step of manufacturing the yield anchor, the inner sleeve includes two semicircular steel pipes of the same size, and the protrusions are welded on the outer wall surfaces of the semicircular steel pipes.

[0016] As a preferred implementation, in the step of manufacturing the yield anchor rod, the number of the protrusions provided on each of the semicircular steel pipes is 2 to 5.

[0017] As a preferred embodiment, in the step of manufacturing the yield anchor rod, the protrusion is provided in a cylindrical shape and extends radially, and the end of the protrusion is conical.

[0018] As a preferred embodiment, in the step of manufacturing the yield anchor rod, the outer sleeve is configured to be in the shape of a round tube, and the outer wall of the outer sleeve is covered with threads.

[0019] As a preferred embodiment, in the step of manufacturing the yield anchor rod, the first opening is arranged at the center of the outer sleeve along the axial direction; and the circumferential dimension of the first opening is equal to the circumferential dimension of the protrusion.

[0020] As a preferred embodiment, in the step of inserting the grouting pipe from the inner sleeve for grouting, the calculation formula of the grouting pressure is:

[0021]

[0022] Among them, F c is the force of the protrusion inserting into the surrounding rock, σ s is the compressive strength of the surrounding rock; d cis the diameter of the protrusion; z is the grouting pressure; k is the adjustment coefficient, which is related to the length of the protrusion and the integrity of the surrounding rock, and is 1.5 to 2; L n is the length of the inner sleeve; B n is the width of the inner sleeve.

[0023] As a preferred embodiment, the connecting mechanism includes bolts, pads and nuts; the pads are provided with a second opening for the head end of the outer sleeve to pass through; the step of installing the connecting mechanism at the head end of the outer sleeve includes: first fixing the pad to the surrounding rock through the bolts, and then installing the nut on the head end of the outer sleeve passing through the second opening.

[0024] As a preferred embodiment, the interior of the nut is hollow to accommodate part of the inner sleeve.

[0025] Beneficial effects:

[0026] The application method of the new type of pressure-yielding anchor provided in the present embodiment is characterized in that the outer wall surface of the inner sleeve is provided with a protrusion, thereby expanding the anchoring area; the wall surface of the outer sleeve is provided with a first opening for the protrusion to pass through, and the axial length of the first opening is set to be greater than the axial length of the outer wall surface provided with the protrusion, so that when the surrounding rock is deformed, the inner sleeve can slide in the outer sleeve within a certain range, releasing part of the deformation pressure of the surrounding rock and reducing the stress on the support structure, thereby solving the problem that when the rock and soil body is subjected to greater pressure, the traditional anchor rod may be damaged or fail due to the inability to release the pressure in time.

[0027] In addition, a cement roll is installed at the tail end of the outer sleeve. Puncturing the cement roll can allow the cement to flow out and solidify quickly, which can enhance the anchoring performance of the anchor rod.

[0028] In addition, the grouting pipe is inserted from the inner sleeve for grouting, the inner sleeve is expanded by the grouting pressure, and the raised part is inserted into the surrounding rock for anchoring to realize the resistance of the anchor rod; the pressure release is realized by the displacement of the inner and outer sleeves, which not only has prestressing and anchoring performance, but also can slide to release pressure and release pressure in time.

[0029] With reference to the following description and the accompanying drawings, the specific embodiments of the present invention are disclosed in detail, indicating the manner in which the principles of the present invention can be adopted. It should be understood that the embodiments of the present invention are not limited in scope thereby.

[0030] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0031] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps or components. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying creative labor.

[0033] Figure 1 A flowchart of the steps of a method for applying a novel pressure-yielding anchor provided in this embodiment;

[0034] Figure 2 for Figure 1 A schematic diagram of the structure of the yield anchor produced in step S10;

[0035] Figure 3 Figure 2 Schematic diagram of the structure of the inner sleeve.

[0036] Description of reference numerals:

[0037] 1. pad; 11. second opening; 2. bolt; 3. nut; 4. outer sleeve; 41. first opening; 5. inner sleeve; 51. semicircular steel pipe; 52. raised portion; 6. cement roll. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0039] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be another element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be another element centered thereon at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0041] See also Figure 1 The present application provides a novel application method of a yield anchor rod, comprising the following steps:

[0042] Step S10: making a yield anchor rod.

[0043] The pressure anchor rod comprises an outer sleeve 4 and an inner sleeve 5. The inner sleeve 5 is arranged in the outer sleeve 4. A protrusion 52 is arranged on the outer wall of the inner sleeve 5. A first opening 41 is arranged on the wall of the outer sleeve 4, and the protrusion 52 is passed through the first opening 41. The axial length of the first opening 41 is greater than the axial length of the outer wall of the inner sleeve 5 on which the protrusion 52 is arranged.

[0044] Step S20: drilling a hole and cleaning the inside of the hole.

[0045] Step S30: installing the cement medicine roll 6 at the rear end of the outer sleeve 4.

[0046] Step S40: Push the yield anchor rod into the borehole until it reaches the designed position.

[0047] Step S50: inserting a grouting pipe from the inner sleeve 5 to perform grouting, and pushing the raised portion 52 into the surrounding rock for anchoring by the grouting pressure.

[0048] Step S60: installing a connection mechanism at the head end of the outer sleeve 4 to fix the pressure anchor rod to the surrounding rock.

[0049] The application method of the new type of pressure-yielding anchor provided in the present embodiment is that the pressure-yielding anchor is provided with a protrusion 52 on the outer wall surface of the inner sleeve 5, thereby expanding the anchoring area; the wall surface of the outer sleeve 4 is provided with a first opening 41 for the protrusion 52 to pass through, and the axial length of the first opening 41 is set to be greater than the axial length of the outer wall surface with the protrusion 52, so that when the surrounding rock is deformed, the inner sleeve 5 can slide in the outer sleeve 4 within a certain range, releasing part of the deformation pressure of the surrounding rock and reducing the stress on the support structure, thereby solving the problem that when the rock and soil body is subjected to greater pressure, the traditional anchor may be damaged or fail due to the inability to release the pressure in time.

[0050] Also, a cement medicine roll 6 is installed at the tail end of the outer sleeve 4. Puncturing the cement medicine roll 6 can make cement flow out and solidify quickly, thereby strengthening the anchoring performance of the anchor rod.

[0051] In addition, a grouting pipe is inserted from the inner sleeve 5 for grouting, the inner sleeve 5 is stretched open by the grouting pressure, and the raised portion 52 is inserted into the surrounding rock for anchoring to achieve anchor resistance; pressure relief is achieved by shifting the inner and outer sleeves 4, thereby not only having prestressing and anchoring properties, but also being able to slide and relieve pressure to release pressure in time.

[0052] In this embodiment, in the step of making the yield anchor (i.e., step S10), the resistance calculation formula of the yield anchor is:

[0053]

[0054] Among them, F k is the resistance of the yield anchor; τ is the shear strength of the surrounding rock; L c is the length of the protrusion 52; μ is the friction coefficient between the protrusion 52 and the surrounding rock; σ s is the compressive strength of the surrounding rock; d c is the diameter of the protrusion 52 .

[0055] Therefore, the resistance of the anchor rod can be calculated by the shear strength of the surrounding rock, the compressive strength of the surrounding rock, the size and number of the protrusions 52, and the friction between the surrounding rock and the protrusions 52, so as to determine the size and number of the protrusions 52 and the relevant parameters of the yield anchor rod to make the yield anchor rod. Specifically, the resistance of the yield anchor rod can be determined according to the on-site deformation suppression requirements, and then the relevant parameters of the yield anchor rod can be determined to make the yield anchor rod meet the requirements and exert the anchoring performance and sliding yield performance accordingly.

[0056] Specifically, in step S10, Figure 2 and Figure 3 As shown, the inner sleeve 5 includes two semicircular steel pipes 51 of the same size, and the protrusion 52 is welded on the outer wall surface of the semicircular steel pipe 51. The two semicircular steel pipes 51 are used for high-pressure grouting. Through high-pressure grouting, the two semicircular steel pipes 51 are separated, and the protrusion 52 can be pushed out from the first opening 41 of the outer sleeve 4, so that the protrusion 52 is inserted into the surrounding rock. Correspondingly, there are two first openings 41 on the outer sleeve 4, and the two first openings 41 are arranged opposite to each other.

[0057] In step S10, the number of the protrusions 52 provided on each of the semicircular steel tubes 51 is preferably 2 to 5. The multiple protrusions 52 are evenly spaced and aligned in the axial direction. The circumferential dimension of the first opening 41 is set equal to the circumferential dimension of the protrusions 52, so that the inner sleeve 5 can only move axially relative to the outer sleeve 4, and cannot move circumferentially. Alternatively, the circumferential dimension of the first opening 41 is slightly larger than the circumferential dimension of the protrusions 52, so that the circumferential movement of the inner sleeve 5 relative to the outer sleeve 4 can be ignored.

[0058] Preferably, the protrusion 52 is cylindrical and extends radially, and can be pushed out from the first outlet after high-pressure grouting in the inner sleeve 5 and inserted into the surrounding rock to enhance the anchoring performance of the anchor rod. Figure 3 As shown, the end of the protrusion 52 is conical, which is convenient for inserting into the surrounding rock. In this specification, the length of the protrusion 52 is the length of the protrusion 52 along the radial direction, and the diameter of the protrusion 52 is the diameter of the cylindrical protrusion 52.

[0059] like Figure 2 As shown, the outer sleeve 4 is provided in a round tube shape, and the outer wall of the outer sleeve 4 is covered with threads, which can enhance the anchoring performance of the anchor rod. The first opening 41 is preferably located at the center of the outer sleeve 4 along the axial direction.

[0060] In this embodiment, in the step of inserting the grouting pipe from the inner sleeve 5 for grouting (i.e., step S50), the calculation formula of the grouting pressure is:

[0061]

[0062] Among them, F c is the force of the protrusion 52 inserting into the surrounding rock, σ s is the compressive strength of the surrounding rock; d c P is the diameter of the protrusion 52; z is the grouting pressure; k is the adjustment coefficient, which is related to the length of the protrusion 52 and the integrity of the surrounding rock, and is 1.5 to 2; L n B is the length of the inner sleeve 5; n is the width of the inner sleeve 5.

[0063] That is, the pressure required for the protrusion 52 to be inserted into the surrounding rock can be calculated by the surrounding rock compressive strength, the size and number of the protrusions 52, and the size of the inner sleeve 5, so as to determine the grouting pressure in the anchor pipe. In order to improve the construction efficiency, the calculation process of the grouting pressure can also be carried out in step S10, and grouting can be carried out according to the calculation result of the grouting pressure in step S50. This solution can calculate the size of the yield anchor and the grouting pressure according to the field parameters such as the surrounding rock strength and the surrounding rock pressure, so that the yield anchor meets the design requirements and exerts the anchoring performance and the sliding yield performance accordingly.

[0064] like Figure 2As shown, the connection mechanism includes a bolt 2, a pad 1 and a nut 3. The pad 1 is provided with a second opening 11 for the head end of the outer sleeve 4 to pass through. After the grouting is completed, step S60 is performed. The step S60 includes: firstly fixing the pad 1 to the lining or surrounding rock through the bolt 2, and then installing the nut 3 to the head end of the outer sleeve 4 passing through the second opening 11. The nut 3 can seal the head end of the outer sleeve 4 to prevent the inner sleeve 5 from moving out with excess mortar.

[0065] Specifically, the nut 3 is hollow inside to accommodate part of the inner sleeve 5, so as to facilitate the inner sleeve 5 to slide inside the outer sleeve 4 and release the pressure in time.

[0066] In step S20, a corresponding drilling device may be used to perform a drilling operation, and the hole may be cleaned after drilling. In step S40, the yield anchor may be slowly pushed into the borehole manually or mechanically. In step S60, the yield anchor may be fixed to the surrounding rock or lining, and the yield anchor may be achieved by deforming the inner sleeve 5 of the yield anchor and the surrounding rock or lining together.

[0067] It should be noted that, in the description of this specification, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of this specification, unless otherwise specified, the meaning of "plurality" is two or more.

[0068] Any numerical value cited herein includes all values ​​of lower and upper values ​​that increase by one unit from the lower limit to the upper limit, and there is at least a two-unit interval between any lower value and any higher value. For example, if the value of the quantity of a component or a process variable (such as temperature, pressure, time, etc.) is stated to be from 1 to 90, preferably from 20 to 80, and more preferably from 30 to 70, the purpose is to illustrate that values ​​such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 are also explicitly listed in the specification. For values ​​less than 1, one unit is appropriately considered to be 0.0001, 0.001, 0.01, 0.1. These are merely examples that are intended to be clearly expressed, and it can be considered that all possible combinations of numerical values ​​listed between the lowest value and the highest value are clearly stated in the specification in a similar manner.

[0069] Unless otherwise indicated, all ranges include the endpoints and all numbers between the endpoints. "About" or "approximately" used with a range applies to both endpoints of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30", including at least the specified endpoints.

[0070] All articles and references disclosed, including patent applications and publications, are incorporated herein by reference for all purposes. The term "consisting essentially of..." to describe a combination should include the identified elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe a combination of elements, ingredients, parts or steps herein also contemplates embodiments that consist essentially of these elements, ingredients, parts or steps. By using the term "may", it is intended to indicate that any attribute described that "may" include is optional.

[0071] Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "an" used to describe an element, ingredient, part or step is not intended to exclude other elements, ingredients, parts or steps.

[0072] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but should be determined with reference to the appended claims and the full scope of equivalents possessed by such claims. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to be a waiver of the subject matter, nor should it be considered that the inventors did not consider the subject matter to be part of the disclosed inventive subject matter.

Claims

1. A new type of pressure anchor application method, characterized in that: The following steps are involved: A yield anchor is manufactured; the yield anchor comprises an outer sleeve and an inner sleeve; the inner sleeve is arranged in the outer sleeve; a protrusion is arranged on the outer wall of the inner sleeve; a first opening is arranged on the wall of the outer sleeve, and the protrusion is passed through the first opening; the axial length of the first opening is greater than the axial length of the outer wall of the inner sleeve on which the protrusion is arranged; Drilling and cleaning holes; Installing a cement roll at the rear end of the outer sleeve; Pushing the yield anchor rod into the borehole until it reaches the designed position; Inserting a grouting pipe from the inner sleeve to perform grouting, and pushing the raised portion into the surrounding rock for anchoring by the grouting pressure; A connecting mechanism is installed at the head end of the outer sleeve to fix the pressure anchor rod to the surrounding rock.

2. The application method of the new pressure-yielding anchor rod according to claim 1 is characterized in that: In the step of making the yield anchor rod, the resistance calculation formula of the yield anchor rod is: Among them, F k is the resistance of the yield anchor; τ is the shear strength of the surrounding rock; L c is the length of the protrusion; μ is the friction coefficient between the protrusion and the surrounding rock; σ s is the compressive strength of the surrounding rock; d c is the diameter of the protrusion.

3. The application method of the new pressure-yielding anchor rod according to claim 1 is characterized in that: In the step of making the yield anchor rod, the inner sleeve includes two semicircular steel pipes of the same size, and the protrusions are welded on the outer wall surfaces of the semicircular steel pipes.

4. The application method of the new pressure-yielding anchor rod according to claim 3 is characterized in that: In the step of making the yield anchor rod, the number of the protrusions arranged on each of the semicircular steel pipes is 2 to 5.

5. The application method of the new pressure-yielding anchor rod according to claim 4 is characterized in that: In the step of manufacturing the yield anchor rod, the protrusion is arranged to be cylindrical and extend radially, and the end of the protrusion is conical.

6. The application method of the new pressure-yielding anchor rod according to claim 1 is characterized in that: In the step of manufacturing the yield anchor rod, the outer sleeve is arranged to be in the shape of a round tube, and the outer wall of the outer sleeve is covered with threads.

7. The application method of the new pressure-yielding anchor rod according to claim 6 is characterized in that: In the step of manufacturing the yield anchor, the first opening is arranged at the center of the outer sleeve along the axial direction; and the circumferential dimension of the first opening is equal to the circumferential dimension of the protrusion.

8. The application method of the new pressure-yielding anchor rod according to claim 1 is characterized in that: In the step of inserting the grouting pipe from the inner sleeve for grouting, the calculation formula of the grouting pressure is: Among them, F c is the force of the protrusion inserting into the surrounding rock, σ s is the compressive strength of the surrounding rock; d c is the diameter of the protrusion; z is the grouting pressure; k is the adjustment coefficient, which is related to the length of the protrusion and the integrity of the surrounding rock, and is 1.5 to 2; L n is the length of the inner sleeve; B n is the width of the inner sleeve.

9. The application method of the new pressure-yielding anchor rod according to claim 1 is characterized in that: The connecting mechanism includes bolts, a pad and a nut; the pad is provided with a second opening for the head end of the outer sleeve to pass through; the step of installing the connecting mechanism at the head end of the outer sleeve includes: first fixing the pad to the surrounding rock through the bolts, and then installing the nut on the head end of the outer sleeve passing through the second opening.

10. The application method of the new pressure-yielding anchor rod according to claim 9 is characterized in that: The nut is arranged to be hollow inside so as to accommodate part of the inner sleeve.

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