Progressive expansion anchor rod suitable for hard rock stratum and construction method of progressive expansion anchor rod

Abstract

The invention relates to the technical field of building construction, in particular to a progressive expansion anchor rod suitable for a hard rock stratum and a construction method of the progressive expansion anchor rod. The device comprises an anchor rod and a sleeve expansion body barb, a main body of the sleeve is of a cylindrical structure with a certain length, and a plurality of control clamping holes are formed in the wall of the sleeve in the length direction of the sleeve. An internal thread is processed on the inner wall of the sleeve; the expanding body barb is inserted into the control clamping hole; an external thread matched with the internal thread of the sleeve for use is processed on the outer wall of the anchor rod; and the anchor rod is inserted into the sleeve and is fastened and screwed through threads, and the barb of the expansion body is extruded outwards. According to the technical scheme, the problem that in the prior art, a resin anchoring anchor rod is insufficient in bonding strength is solved; a mechanical expansion anchor rod is complex in structure and difficult to install, and the anchoring force cannot be gradually enhanced; the disposable expansion design of the expansion anchor rod cannot adapt to the stress redistribution process of the rock mass, and particularly, the problems that the anchoring force is attenuated due to creep deformation of the rock mass in a deep high ground stress environment and the like are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and in particular to a progressively expanded anchor rod suitable for hard rock formations and a construction method thereof. Background Art

[0002] As mining depths continue to increase, complex geological conditions such as high ground stress and rock fragmentation have placed higher demands on tunnel support technology. In hard rock formations, traditional anchor support faces prominent problems such as insufficient anchoring force and easy failure. Although the resin anchor bolts that are currently widely used can provide a high initial anchoring force, they often have insufficient bonding strength in hard rock due to the smooth borehole wall, and the grouting process is easily affected by rock cracks; and although mechanically expanded anchor bolts can increase bearing capacity by expanding the diameter of the end, they generally have complex structures, difficult installation, and inability to achieve gradual increase in anchoring force. In addition, existing expanded anchor bolts mostly use a one-time expansion design, which cannot adapt to the rock stress redistribution process, especially in deep high-ground stress environments, the anchoring force is easily attenuated due to rock creep.

[0003] In view of the problems existing in the above-mentioned prior art, it is very necessary to research and design a new type of progressively expanded anchor rod suitable for hard rock formations and a construction method thereof, so as to overcome the problems existing in the prior art. Summary of the Invention

[0004] According to the above-mentioned prior art, the resin anchor bolts proposed have insufficient bonding strength; the mechanically expanded anchor bolts have complex structures, are difficult to install, and cannot achieve a gradual increase in anchoring force; the one-time expansion design of the expanded anchor bolt cannot adapt to the rock stress redistribution process, especially in deep high-stress environments, which is prone to rock creep leading to attenuation of anchoring force and other technical problems. Therefore, a progressively expanded anchor bolt suitable for hard rock formations and its construction method are provided. The present invention mainly achieves a graded increase in resistance during the screwing-in process of the anchor bolt through the synergistic effect of the threaded sleeve and the inverted conical expanded inner rod. With each additional screwing-in area, the expanded barb forms a new bite point with the rock mass, causing the anchoring force to increase in a step-by-step manner. It breaks through the industry problem of "high initial strength but poor sustained stability" in hard rock anchoring, and the anchoring force can be adjusted at any time according to the screwing-in depth, providing an innovative solution for surrounding rock control in deep mining, tunnel engineering and other fields, with significant technical and economic advantages.

[0005] The technical means adopted in the present invention are as follows:

[0006] A progressively expanded anchor rod suitable for hard rock formations comprises: an anchor rod, a sleeve expanded body barb;

[0007] Furthermore, the main body of the sleeve is a cylindrical structure with a certain length, and a plurality of control holes are provided on the cylindrical wall along the length direction thereof;

[0008] Furthermore, an internal thread is processed on the inner wall of the sleeve;

[0009] Further, the expanded body barb is inserted into the control card hole;

[0010] Furthermore, an external thread is machined on the outer wall of the anchor rod to cooperate with the internal thread of the sleeve;

[0011] Furthermore, the anchor rod is inserted into the sleeve and screwed together through threaded fastening, and the expanded body barb is pressed outward.

[0012] Furthermore, an internal thread for screwing with the anchor rod is processed inside the smooth section of the sleeve in the middle of the sleeve;

[0013] Furthermore, the length of the internal thread of the sleeve needs to be greater than the external thread processed on the outer wall of the anchor rod so that it can effectively bear the force when rotating inward, and avoid the internal thread of the sleeve being too short to rotate the anchor rod inward.

[0014] Furthermore, the front end of the sleeve is processed with a sleeve anti-slip section composed of a plurality of spikes.

[0015] Further, the expanded barb includes a barb body;

[0016] Furthermore, a barb force-bearing tip is processed on the outer side of the upper portion of the barb body.

[0017] Furthermore, the outer portion of the expanded body barb is adapted to the inner hole size of the control card hole and has a certain contact force to prevent the expanded body barb from falling off when assembled in the control card hole.

[0018] Furthermore, the rod body of the anchor rod is composed of a rear anchor rod smooth section and a front vertebral driving section;

[0019] Furthermore, a plurality of vertebrae connected in sequence are processed on the vertebral driving section;

[0020] Furthermore, the rear portion of the conical body is processed with a rod thread section for threaded connection with the sleeve;

[0021] Furthermore, after the anchor rod is screwed into the sleeve, the vertebral body driving section gradually pushes the expanded body barb outward.

[0022] Furthermore, the rear end of the anchor rod is processed with an anchor rod thread section for assembling the anchor stiffening plate and the high-strength anchor nut.

[0023] Furthermore, the construction method of the progressively expanded anchor bolt suitable for hard rock formations includes the following steps:

[0024] Step 1: Insert the anchor rod into the sleeve and gradually screw it into the anti-slip section of the sleeve. A certain size should be reserved between the front end of the anchor rod and the anti-slip section of the sleeve to facilitate further screwing of the anchor rod.

[0025] Step 2: Place the barb body of the expanded barb into the control hole of the sleeve, with the tip of the barb facing upwards;

[0026] Step 3: Drill an anchor hole in the rock mass using drilling equipment. The size of the anchor hole must be consistent with the size of the sleeve.

[0027] Step 4: Insert the sleeve equipped with the anchor rod and the expanded barb into the anchor hole as a whole, so that the anti-slip section of the sleeve is in close contact with the bottom foundation of the anchor hole to ensure anti-slip during rotation. Then screw the anchor rod in further. At this time, the conical driving section will push the expanded barb outward and rotate it slightly, so that it is embedded in the surrounding rock. As the anchor rod is screwed in deeper, the anchoring force increases.

[0028] Step 5: Put the anchor plate over the anchor thread section and tighten it with high-strength anchor nuts to ensure overall force.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. The progressively enlarged anchor bolt and its construction method, suitable for hard rock formations, provided by the present invention, adopt a self-locking enlarged barb structure, achieving high-strength anchoring without injecting mortar, effectively avoiding the slurry loss problem in hard rock during traditional grouting processes, and making the construction process more environmentally friendly.

[0031] 2. The progressively expanded anchor bolt and its construction method provided by the present invention are suitable for hard rock formations. All components of the anchor bolt can be standardized and processed in the factory. Only simple assembly is required on site, eliminating the complex on-site welding and grouting processes required for traditional anchor bolts, thereby greatly improving construction efficiency.

[0032] 3. The progressively enlarged anchor bolt and its construction method, suitable for hard rock formations, provided by the present invention, utilize a unique thread-barb collaborative design to gradually increase resistance when the bolt is screwed in, forming multiple anchoring points. This ensures high anchoring force while requiring a lower drill hole diameter, reducing the difficulty of drilling.

[0033] 4. The progressively expanding anchor rod and its construction method provided by the present invention are suitable for hard rock formations. In response to stress relaxation or creep deformation of rock and soil, the anchor rod depth can be adjusted by screwing it in a second time, and the bite action of the barb can be reactivated to achieve long-term stable control of the anchoring force and extend the support life.

[0034] In summary, the application of the technical solution of the present invention solves the problems of insufficient bonding strength of resin anchor rods in the prior art; the mechanically expanded anchor rod has a complex structure, is difficult to install, and cannot achieve gradual enhancement of the anchoring force; the one-time expansion design of the expanded anchor rod cannot adapt to the rock stress redistribution process, and is particularly prone to attenuation of the anchoring force due to rock creep in deep and high ground stress environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0036] Figure 1 This is a schematic diagram of the structure of the present invention placed inside the anchor hole;

[0037] Figure 2 It is a schematic diagram of the structure of the present invention;

[0038] Figure 3 This is a schematic diagram of the anchor rod structure of the present invention;

[0039] Figure 4 This is a schematic structural diagram of the anchor rod vertebral driving section of the present invention;

[0040] Figure 5 This is a schematic diagram of the sleeve structure of the present invention;

[0041] Figure 6 Schematic diagram of the internal structure of the sleeve of the present invention;

[0042] Figure 7 This is a schematic diagram of the expanded barb structure of the present invention;

[0043] Figure 8 This is a schematic diagram of the structure of the anchor stiffening plate of the present invention;

[0044] Figure 9 This is a schematic diagram of the structure of the high-strength anchor nut of the present invention.

[0045] In the figure: 1, anchor rod 101, anchor rod smooth section 102, vertebral drive section 103, rod body threaded section 104, anchor rod threaded section 2, sleeve 201, sleeve smooth section 202, control clamping hole 203, sleeve anti-slip section 3, anchor stiffening plate 4, high-strength anchor nut 5, expanded body hook 501, hook body 502, and hook force-bearing tip. DETAILED DESCRIPTION

[0046] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0049] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0050] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0051] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0052] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0053] like Figure 1-6 As shown, the present invention provides a progressively expanding anchor rod suitable for hard rock formations, comprising: an anchor rod 1, a sleeve 2, and an expanding barb 5; the main body of the sleeve 2 is a cylindrical structure with a certain length, and a plurality of control clamping holes 202 are provided on the cylindrical wall along its length direction; an internal thread is processed on the inner wall of the sleeve 2; the expanding barb 5 is inserted into the control clamping hole 202; an external thread is processed on the outer wall of the anchor rod 1 for use with the internal thread of the sleeve 2; the anchor rod 1 is inserted into the sleeve 2 and screwed together by thread tightening, and the expanding barb 5 is squeezed outward.

[0054] like Figure 5-6 As shown, the interior of the sleeve smooth section 201 in the middle of the sleeve 2 is processed with an internal thread for screwing with the anchor rod 1;

[0055] like Figure 5-6 As shown, the length of the internal thread of the sleeve 2 needs to be greater than the external thread processed on the outer wall of the anchor rod 1 so that it can effectively bear the force when rotating inward, and avoid the internal thread of the sleeve 2 being too short to rotate the anchor rod 1 inward.

[0056] like Figure 5-6 As shown, the front end of the sleeve 2 is processed with a sleeve anti-slip section 203 composed of a plurality of spikes.

[0057] like Figure 7 As shown, the expanded barb 5 includes a barb body 501 ; a barb force-bearing tip 502 is processed on the outer side of the upper portion of the barb body 501 .

[0058] like Figure 1As shown, the outer portion of the expanded body barb 5 is adapted to the inner hole size of the control card hole 202 and has a certain contact force to prevent the expanded body barb 5 from falling off when assembled in the control card hole 202.

[0059] like Figure 1-6 As shown, the rod body of the anchor rod 1 is composed of a smooth anchor rod section 101 at the rear and a vertebral driving section 102 at the front; a plurality of vertebral bodies connected in sequence are processed on the vertebral driving section 102; a rod threaded section 103 for threaded connection with the sleeve 2 is processed at the rear of the cone; after the anchor rod 1 is screwed together with the sleeve 2, the vertebral driving section 102 gradually pushes the expanded body barb 5 outward.

[0060] like Figure 2-3 As shown, the rear end of the anchor rod 1 is processed with an anchor rod thread section 104 for assembling the anchor stiffening plate 3 and the high-strength anchor nut 4.

[0061] The construction method of the progressively enlarged anchor bolt suitable for hard rock formations includes the following steps:

[0062] Step 1: Insert the anchor rod 1 into the sleeve 2 and gradually screw it into the sleeve anti-slip section 203; a certain size should be reserved between the front end of the anchor rod 1 and the sleeve anti-slip section 203 to facilitate further screwing of the anchor rod 1 later;

[0063] Step 2: Place the barb body 501 of the expanded barb 5 into the control clamping hole 202 of the sleeve 2, with the barb force-bearing tip 502 facing upwards;

[0064] Step 3: Drill an anchor hole 7 in the rock mass using a drilling device. The size of the anchor hole 7 must be consistent with the size of the sleeve 2.

[0065] Step 4: Insert the sleeve 2 equipped with the anchor rod 1 and the expanded barb 5 into the anchor hole 7 as a whole, so that the sleeve anti-slip section 203 is in close contact with the bottom foundation of the anchor hole 7 to ensure anti-slip during rotation, and further screw in the anchor rod 1. At this time, the conical driving section 102 will push the expanded barb 5 outward and rotate it slightly, so that it is embedded in the surrounding rock. As the anchor rod 1 is screwed in deeper, the anchoring force is enhanced.

[0066] Step 5: Put the anchor plate 3 on the anchor thread section 104 and tighten it with the high-strength anchor nut 4 to ensure the overall force.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A progressively expanded anchor suitable for hard rock formations, characterized by: The progressively expanded anchor rod suitable for hard rock formations comprises: an anchor rod (1), a sleeve (2) and an expanded barb (5); The main body of the sleeve (2) is a cylindrical structure with a certain length, and a plurality of control holes (202) are provided on the wall of the sleeve along the length direction; The inner wall of the sleeve (2) is processed with an internal thread; The enlarged barb (5) is inserted into the control clamp hole (202); The outer wall of the anchor rod (1) is processed with an external thread that cooperates with the internal thread of the sleeve (2); The anchor rod (1) is inserted into the sleeve (2) and screwed together by screw thread, and the expanded barb (5) is pressed outward.

2. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The interior of the sleeve smooth section (201) in the middle of the sleeve (2) is processed with an internal thread for screwing with the anchor rod (1).

3. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The length of the internal thread of the sleeve (2) must be greater than the external thread processed on the outer wall of the anchor rod (1) so that it can effectively bear the force when rotating inward, and avoid the internal thread of the sleeve (2) being too short to rotate the anchor rod (1) inward.

4. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The front end of the sleeve (2) is processed with a sleeve anti-slip section (203) consisting of a plurality of spikes.

5. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The enlarged barb (5) comprises a barb body (501); The outer side of the upper portion of the barb body (501) is processed with a barb force-bearing tip (502).

6. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The outer portion of the expanded body barb (5) is adapted to the inner hole size of the control card hole (202) and has a certain contact force to prevent the expanded body barb (5) from falling off when assembled in the control card hole (202).

7. The progressively expanded anchor bolt suitable for hard rock formations according to claim 1, characterized in that: The rod body of the anchor rod (1) is composed of a rear anchor rod smooth section (101) and a front vertebral driving section (102); The vertebral driving section (102) is processed with a plurality of vertebral bodies connected in sequence; The rear portion of the conical body is processed with a rod thread section (103) for threaded connection with the sleeve (2); After the anchor rod (1) and the sleeve (2) are screwed together, the vertebral body driving section (102) gradually pushes the body expansion barb (5) outward.

8. The progressively expanded anchor bolt suitable for hard rock formations according to claim 7, characterized in that: The rear end of the anchor rod (1) is processed with an anchor rod thread section (104) for assembling an anchor stiffening plate (3) and a high-strength anchor nut (4).

9. A construction method for a progressively enlarged anchor bolt suitable for hard rock formations, characterized by: The construction method comprises the following steps: Step 1: Insert the anchor rod (1) into the sleeve (2) and gradually screw it into the sleeve anti-slip section (203); a certain size is required to be reserved between the front end of the anchor rod (1) and the sleeve anti-slip section (203) so that the anchor rod (1) can be screwed in later; Step 2: Place the barb body (501) of the expanded barb (5) into the control clamping hole (202) of the sleeve (2), with the barb force-bearing tip (502) facing upwards; Step 3: Drill an anchor hole (7) in the rock mass using a drilling device. The size of the anchor hole (7) must be consistent with the size of the sleeve (2); Step 4: Insert the sleeve (2) equipped with the anchor rod (1) and the expanded body barb (5) into the anchor hole (7) as a whole, so that the sleeve anti-slip section (203) is in close contact with the bottom foundation of the anchor hole (7) to ensure anti-slip during rotation, and further screw in the anchor rod (1). At this time, the conical driving section (102) will push the expanded body barb (5) to move outward and rotate slightly, so that it is embedded in the surrounding rock. As the anchor rod (1) is screwed into the depth, the anchoring force is enhanced; Step 5: Put the anchor plate (3) on the anchor thread section (104) and tighten it with the high-strength anchor nut (4) to ensure the overall force.

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