Gob-side entry retaining gangue retaining support composite anchor rod
By employing a composite structure of slotted and embedded anchor bolts in the goaf-side roadway of a coal mine, and utilizing the fit between the inverted wedge and the wedge block, the radial support force and axial friction force are enhanced, forming a double-layer rock-blocking structure. This solves the problem of poor support effect in existing technologies and achieves higher rock-blocking capacity and roadway stability.
Patent Information
- Application Number
- CN202520074734.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2035-01-14
AI Technical Summary
Existing slotted anchor bolts are easily affected by the intrusion of gangue in coal mine goaf-side roadways, resulting in poor support effect, difficulty in adapting to complex and variable surrounding rock stress environment, and easy pull-out, insufficient radial support force and axial friction force.
A composite structure of slotted pipe anchors and embedded anchors is adopted. The inverted wedges of the embedded anchors fit with the wedge blocks to enhance radial support and axial friction, forming a double-layer retaining structure. The support performance is improved through the cooperation of the wedge blocks and inverted wedges.
It significantly improves the stability and rock-blocking capacity of the retaining wall in the goaf roadway, enhances the support effect, effectively resists the deformation of the surrounding rock, forms a double-layer rock-blocking defense line, and improves the safety and stability of the goaf roadway.
Smart Images
Figure CN223634736U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of coal mine roadway supporting device, and concretely relates to a composite anchor rod for gob-side entry retaining and gangue retaining. BACKGROUND
[0002] In the process of coal mining, gob-side entry retaining technology is of great significance for improving the coal recovery rate and reducing the amount of roadway excavation engineering. For relatively thin coal seams, in the gob-side entry retaining operation, the side of the gob-side entry retaining is the entity coal to be mined, and the other side is the broken gangue in the goaf. The gangue near the gob-side entry retaining in the goaf is reinforced by anchor rods and supported by single props as a retaining wall for gob-side entry retaining. The gob-side entry retaining wall bears the lateral pressure of the gangue in the other areas of the goaf that are not reinforced. Therefore, the anchor rod support for the gob-side entry retaining wall is a key link in gob-side entry retaining, and it is of great significance to the stability of the gob-side entry retaining and the safety of the operating personnel.
[0003] The gob-side entry retaining wall of the above form is usually supported by a pipe slot anchor rod. The pipe slot anchor rod is a hollow pipe body with a slot arranged along the axial direction. The diameter of the pipe body is slightly larger than the drilling hole for installing the anchor rod. After the pipe slot anchor rod is installed in the drilling hole, the pipe slot is contracted and pressed against the hole wall. However, on the one hand, since the pipe slot anchor rod has a pipe slot, gangue may enter the pipe body, affecting the support work of the pipe body and safety. On the other hand, the surrounding of the pipe slot anchor rod is gangue. The deformation and movement of the gangue easily lead to an increase in the hole diameter, resulting in the easy pulling out of the retaining ring of the pipe slot anchor rod, insufficient radial support force, and insufficient axial friction force. It is difficult to adapt to the complex and variable stress environment of the surrounding rock of the gob-side entry retaining, resulting in poor gangue retaining effect. SUMMARY
[0004] To solve the above technical problems, the utility model provides a composite anchor rod for gob-side entry retaining and gangue retaining, which comprises a pipe slot anchor rod and an embedded anchor rod. The pipe slot anchor rod comprises a pipe slot anchor rod steel pipe. A pipe slot is arranged along the axial direction of the pipe slot anchor rod steel pipe. A wedge block is arranged on the inner wall of the pipe slot anchor rod steel pipe near the top end. The inner diameter of the wedge block gradually decreases from the top to the bottom. The embedded anchor rod comprises an embedded anchor rod body. A thread is arranged on the outer periphery of the embedded anchor rod body. A reverse wedge is fixed on the top end of the embedded anchor rod body. The reverse wedge is seated in the wedge block. The anchor rod body is located in the pipe slot anchor rod steel pipe. The bottom end of the anchor rod body protrudes out of the bottom end of the pipe slot anchor rod steel pipe. An embedded anchor rod tray is first sleeved on the bottom end of the pipe slot anchor rod steel pipe, and then an embedded anchor rod nut is connected to the thread.
[0005] Preferably, the pipe slot anchor rod steel pipe is a circular pipe.
[0006] Preferably, a pipe slot anchor rod tray is sleeved on the bottom end of the pipe slot anchor rod steel pipe.
[0007] Preferably, a pipe slot anchor rod iron ring is further sleeved on the bottom end of the pipe slot anchor rod steel pipe outside the pipe slot anchor rod tray.
[0008] Preferably, the inverted wedge gradually decreases in diameter from top to bottom, forming a structure matching the inner diameter of the wedge block.
[0009] Preferably, the anchor rod body is coaxially arranged with the tubular slotted anchor rod steel pipe.
[0010] The utility model has the advantages that the gob-side entry retaining and supporting composite anchor rod of the utility model is formed by a tubular slotted anchor rod and an embedded anchor rod, especially the combination of the inverted wedge at the top of the embedded anchor rod and the wedge block in the tubular slotted anchor rod can significantly improve the radial supporting force and the axial friction force of the tubular slotted anchor rod steel pipe, that is, the supporting performance of the tubular slotted anchor rod steel pipe can be significantly improved, the stability of the gob-side entry retaining wall can be effectively enhanced, and the gob retaining capacity of the gob-side entry retaining wall can be improved. BRIEF DESCRIPTION OF DRAWINGS
[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description, and obviously, the drawings in the following description are only some embodiments described in the present application, and for those skilled in the art, other drawings can also be obtained according to these drawings without creating any creative labor.
[0012] Fig. 1 It is a whole structure schematic view of the gob-side entry retaining and supporting composite anchor rod of the utility model.
[0013] Fig. 2 It is an installation structure schematic view of the gob-side entry retaining and supporting composite anchor rod of the utility model.
[0014] In the figure, alpha is the wedge angle of the wedge block, 1 is the tubular slotted anchor rod steel pipe, 2 is the inverted wedge, 3 is the wedge block, 4 is the embedded anchor rod body, 5 is the tubular slotted anchor rod tray, 6 is the tubular slotted anchor rod iron ring, 7 is the embedded anchor rod tray, 8 is the embedded anchor rod nut, 9 is the drill hole, and 10 is the tubular slotted anchor rod pipe joint. DETAILED DESCRIPTION
[0015] The technical solutions of the utility model will be described clearly and completely in combination with specific embodiments and drawings. In the shown embodiments, the direction indications, i.e. up, down, left, right, front and back, are relative, and are used to explain that the structures of different components in the present application are relative. When the components are in the positions shown in the drawings, these indications are appropriate. However, if the positions of the components change, it is considered that these indications will also change accordingly.
[0016] As Figs. 1-2As shown, this utility model proposes a composite anchor bolt for goaf retention and rockfill support, comprising a slotted anchor bolt and an embedded anchor bolt. The slotted anchor bolt includes a circular slotted anchor bolt steel pipe 1, with a slot 10 cut along its axial direction. A slotted anchor bolt tray 5 and a slotted anchor bolt iron ring 6 are sequentially fitted onto the bottom end of the slotted anchor bolt steel pipe 1. A wedge block 3 is internally connected to the inner wall of the slotted anchor bolt steel pipe 1 near the top, and the wedge block 3 is fixedly connected to the slotted anchor bolt steel pipe 1. The inner diameter of the wedge block 3 gradually decreases from top to bottom, forming a wedge angle of size α. The embedded anchor bolt... The system includes an embedded anchor rod body 4, which has threads on its outer circumference and a wedge 2 fixed at its top. The outer diameter of the wedge 2 gradually decreases from top to bottom, forming a structure that matches the inner diameter of the wedge block 3, so that the wedge 2 sits inside the wedge block 3. The anchor rod body 4 is centrally arranged inside the slotted anchor steel pipe 1, that is, it is arranged coaxially with the slotted anchor steel pipe 1. The bottom end of the anchor rod body 4 protrudes beyond the bottom end of the slotted anchor steel pipe 1. An embedded anchor rod tray 7 is first sleeved on it, and then an embedded anchor rod nut 8 is threaded on it. That is, the embedded anchor rod tray 7 is located outside the slotted anchor iron ring 6.
[0017] The installation method and working mechanism of the composite anchor bolt for goaf retention and rock retaining support of this utility model are as follows:
[0018] like Figs. 1-2 As shown, a borehole 9 adapted to the composite anchor bolt of this utility model is drilled in the retaining wall of the goaf-side roadway. The diameter and length of the borehole 9 are slightly smaller than the diameter of the slotted anchor bolt steel pipe 1. Fig. 2 In this diagram, the diameter of borehole 9 is larger than that of the slotted anchor pipe 1 (this is merely to illustrate the installation method of the composite anchor in borehole 9 of the gob-side retaining wall for ease of understanding). The assembled composite anchor is inserted into borehole 9. The portion of the bottom end protruding from borehole 9 is fitted with a slotted anchor tray 5 and a slotted anchor ring 6. An embedded anchor tray 7 is located at the bottom end of both the slotted anchor pipe 1 and the slotted anchor ring 6. Tightening the nut 8 secures the embedded anchor tray 7, which in turn also fixes the slotted anchor tray 5, the slotted anchor ring 6, and the slotted anchor pipe 1. After insertion into borehole 9, the slotted anchor pipe 1 automatically contracts and compresses the borehole wall, immediately applying radial pressure along its entire length. This places the gob-side retaining wall in a triaxial stress state, stabilizing it and preventing the obstruction of debris. When gangue approaches the goaf, the broken gangue is embedded in the slotted bolt 10, and together with the larger outer diameter of the slotted bolt steel pipe 1, it forms the first line of defense against gangue; while the inverted wedge 2 and wedge block 3 further block large pieces of gangue, building the second line of defense against gangue.
[0019] When the tool rotates the embedded anchor rod nut 8 to further apply the pulling force, the embedded anchor rod body 4 pulls the inverted wedge 2 to displace relative to the wedge block 3, increases the engagement degree of the inverted wedge 2 and the wedge block 3, the wedge block 3 expands along the radial direction to press the tubular slot type anchor rod steel pipe 1 to apply the radial support force to the tubular slot type anchor rod, improves the axial friction force, that is, increases the radial support force and the axial friction force of the tubular slot type anchor rod to the gangue, greatly improves the anchoring bearing capacity of the whole composite anchor rod, and effectively resists the deformation of the surrounding rock. In addition, when the embedded anchor rod nut 8 is further pulled, the embedded anchor rod tray 7 and the tubular slot type anchor rod tray 5 can effectively extrude the gangue, thereby improving the anchoring effect and the gangue supporting capacity of the whole composite anchor rod of the utility model.
[0020] It should be understood that, although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be combined appropriately to form other embodiments that those skilled in the art can understand.
[0021] The series of detailed descriptions listed above are only specific descriptions of the feasible embodiments of the utility model, and they are not used to limit the protection scope of the utility model, and any equivalent embodiments or changes made without departing from the spirit of the utility model art should be included in the protection scope of the utility model.
Claims
1. A composite roof support anchor for gob-side entry retaining and rock blocking, characterized in that, The anchor rod comprises a pipe slot anchor rod and an embedded anchor rod, the pipe slot anchor rod comprises a pipe slot anchor rod pipe, the pipe slot anchor rod pipe is provided with a pipe slot along an axial direction of the pipe slot anchor rod pipe, a wedge block is arranged on an inner wall of the pipe slot anchor rod pipe close to a top end side, and an inner diameter of the wedge block gradually decreases from top to bottom; the embedded anchor rod comprises an embedded anchor rod body, a thread is arranged on an outer periphery of the embedded anchor rod body, and an inverted wedge is fixed on a top end of the embedded anchor rod body and is arranged in the wedge block; the anchor rod body is arranged in the pipe slot anchor rod pipe, a bottom end of the anchor rod body is exposed outside a bottom end of the pipe slot anchor rod pipe, an embedded anchor rod tray is first sleeved on the bottom end of the anchor rod body, and then an embedded anchor rod nut is threadedly connected to the embedded anchor rod tray.
2. The composite roof support anchor according to claim 1, wherein, The pipe slot anchor rod pipe is a circular pipe.
3. The composite roof support anchor according to claim 1, wherein, The pipe slot anchor rod pipe is provided with a pipe slot anchor rod tray on a bottom end of the pipe slot anchor rod pipe.
4. The composite roof support bolt of claim 3, wherein, An iron ring of the pipe slot anchor rod is further sleeved on the bottom end of the pipe slot anchor rod pipe outside the pipe slot anchor rod tray.
5. The composite roof support bolt according to any one of claims 1 to 4, wherein the bolt is a gob-side entry retaining and supporting composite bolt. The inverted wedge gradually decreases in an outer diameter from top to bottom, and forms a structure matched with the inner diameter of the wedge block.
6. The composite roof support bolt of claim 5, wherein, The anchor rod body and the pipe slot anchor rod pipe are coaxially arranged.