Composite grouting anchor rod capable of preventing impact damage, construction method and application of composite grouting anchor rod in rock burst prevention

Abstract

The invention relates to an anti-impact-damage composite grouting anchor rod, a construction method and application of the anti-impact-damage composite grouting anchor rod to rockburst prevention, the grouting anchor rod comprises an anchor rod body with a center channel and a spacer arranged in the center channel of the anchor rod body, and the end portion of the first end of the anchor rod body is sleeved with an expansion sleeve; the periphery of the expansion sleeve is expanded when the anchor rod is tightly ejected relative to the expansion sleeve, a plurality of through holes are formed in the position, between the first end and the partition plate, of the anchor rod, a limiting groove is formed in the position, close to the partition plate, in the anchor rod, an anchor connector is arranged in the limiting groove in a bearing mode, the anchor connector is connected with a prestressed pipe, and the right end of the prestressed pipe penetrates out of the second end of the anchor rod. A thread and a nut connected with the thread are arranged at the right end of the prestressed pipe, a resisting disc is connected between the nut and the second end of the anchor rod in an abutting mode, and a conveying pipe capable of penetrating through the spacer is arranged in a center hole of the prestressed pipe. The grouting anchor rod not only can resist tensile failure, but also can prevent shear failure, and the adaptability of anchor rod construction to complex geological environments is improved.

Description

Technical field: The invention relates to a composite grouting anchor rod resistant to impact damage, a construction method and an application of the composite grouting anchor rod in preventing rock burst. Background technology: Tunnel surrounding rock support technology is one of the key technologies to ensure safe and efficient mining in mines. Traditional support methods mainly include wooden supports, steel supports, anchor support, shotcrete support, etc. These methods have been widely used in the past few decades and have achieved certain results. However, in the face of complex and changeable underground conditions, especially when encountering high ground stress areas and mining-affected areas, the limitations of traditional methods have gradually emerged. They are often difficult to adapt to the strong deformation of rocks and the influence of dynamic loads, which can easily cause failure and damage of support structures. In order to overcome these problems, researchers have begun to explore more scientific and efficient new support technologies in recent years. For example, the development of technologies such as retractable supports, high-strength shotcrete, and prestressed anchor cables has greatly improved the overall stability and bearing capacity of the support system.

[0003] Anchor rods are a basic component of underground engineering and slope support systems. Their main function is to reinforce the surrounding rock of tunnels or other underground spaces and use the strength of the surrounding rock to achieve support. Anchor rods are not only widely used in mine tunnels, but also used for the main reinforcement of engineering structures such as slopes, tunnels, and dams. With the complexity of engineering geological conditions, traditional anchor rods can no longer meet the needs of actual construction. Liu Sihui et al. proposed a splitting grouting anchor rod and its construction method (application number: CN202410085675.4). Through a splitting grouting anchor rod, including a hollow anchor rod, a centering rod, an anchor cable, a grouting pipe, a connecting sleeve and an anchor head, the problems existing in certain technologies were solved. Peng Jun et al. proposed an internal expansion grouting anchor rod and its support method for tunnel surrounding rock support (application number: CN202410058358.3), which mainly consists of a rod body, an anchor rod head, a fixing structure, a grouting structure, an exhaust pipe and a sensor structure. Although the introduction of these anchor rods solves the technical problems to a certain extent, the comprehensiveness of the anchor rods is relatively simple and their adaptability to complex conditions is poor. Summary of the invention: In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a composite grouting anchor rod and a construction method that are resistant to impact damage. The composite grouting anchor rod that is resistant to impact damage can resist tensile damage as well as shear damage, thereby improving the adaptability of anchor rod construction to complex geological environments.

[0005] The composite grouting anchor rod of the present invention is characterized in that it includes an anchor rod with a central channel and a spacer arranged in the central channel of the anchor rod, the first end portion of the anchor rod is sleeved with an expansion sleeve, and the outer periphery of the expansion sleeve expands when the anchor rod is tightened relative to the expansion sleeve, a plurality of through holes are arranged on the anchor rod at a position between the first end and the spacer, a limiting groove is provided in the anchor rod near the spacer, an anchor joint is accommodated in the limiting groove, the anchor joint is connected to a prestressed tube with a right end passing through the second end of the anchor rod, the right end of the prestressed tube is provided with a thread and a nut connected to the thread, a stop plate is abutted between the nut and the second end of the anchor rod, and a feed pipe capable of passing through the spacer is provided in the center hole of the prestressed tube.

[0006] Preferably, the limiting groove is in a cone shape, and the anchor joint is also in a cone shape matching the cone.

[0007] Preferably, the above-mentioned spacer is a spacer, and the spacer is fixed at one-third to one-half of the central channel of the anchor rod.

[0008] Preferably, the inner wall of the expansion sleeve is conical, the first end of the anchor rod is also conical, the large end of the cone faces the second end of the anchor rod, and a plurality of slots are arranged in the circumferential direction on the side of the expansion sleeve facing the second end of the anchor rod.

[0009] Preferably, the anchor joint is coaxially arranged with the prestressed pipe and fixed by threaded connection or welding.

[0010] Preferably, the above-mentioned limiting groove is formed by a conical bucket fixed in the central channel of the anchor rod, the large end of the conical bucket is welded to the inner wall of the central channel of the anchor rod, and the small end of the conical bucket is welded to a sleeve, and the center of the sleeve is used to pass the prestressed tube.

[0011] Preferably, the above-mentioned anchor rod is separated into two pipe rods at the position where the spacer is installed, and the two pipe rods are fixed by threaded connection at one end close to each other. The spacer is pressed on the bottom of the threaded groove of the first pipe rod and on the end face of the second pipe rod, and the conical bucket is welded and fixed in the central channel close to the end face of the second pipe rod.

[0012] Preferably, the feed pipe is a plastic pipe, a first end of which passes through the spacer and a second end of which passes through the right end of the prestressed pipe.

[0013] Preferably, the outer periphery of the anchor rod is provided with a constant resistance sleeve made of NPR material or exotic metal material, and the constant resistance sleeve is provided with groove joints evenly distributed circumferentially at both end sides, and the grooves at both ends are staggered in the circumferential direction.

[0014] The construction method of the composite grouting anchor rod that is resistant to impact damage of the present invention comprises the following steps: firstly, a hole is drilled on the rock, an expansion sleeve is put on the anchor rod and then inserted into the drill hole; during the insertion process, due to the force applied to the anchor rod, the expansion sleeve expands to be fastened to the drill hole; then, the nut is rotated to make the anchor joint approach the second end of the anchor rod, so as to further pre-tighten the anchor joint to the limiting groove and the anchor rod; then, concrete slurry is poured into the central channel of the anchor rod through the feed pipe, and the slurry overflows from the through hole into the drill hole; and the anchor rod is fixed after the slurry solidifies.

[0015] The application of the impact-resistant composite grouting anchor rod in preventing rock bursts is characterized by: (1) Applying prestress to the anchor rod: after the anchor rod 2 and the expansion sleeve 4 are placed in the borehole, the feed pipe 11 is passed through the retaining plate 10 and the prestressing pipe 8, and the nut is rotated to apply prestress; (2) High-pressure water injection: high-pressure water is injected along the right end of the conveying pipe 11. The high-pressure water is injected into the high-stress rock mass through the through hole 5. The liquid pressure is used to open and expand the cracks in the rock. By controlling the formation and expansion of the cracks, the purpose of releasing the ground stress is achieved; (3) To release stress in high-risk rock mass, a constant injection pressure must be maintained after high-pressure water is injected; (4) Pumping out pressure. After the high-pressure water has fully exerted its effect and caused the rock mass to fracture, use a pumping device to completely drain the fissure water injected into the rock mass. Grouting reinforcement, after completing the pumping and pressure relief, concrete slurry is injected into the feed pipe through the right end port of the feed pipe 11; with the injection and penetration of the slurry, the slurry gradually fills the cracks and voids in the rock mass, forming an anchoring integrated structure with the anchor rod.

[0016] The main innovations of the present invention are: 1. Energy-absorbing support method: The support system of the present invention can absorb and disperse the energy generated by impact ground pressure instead of just bearing it.

[0017] 2. Research on anti-impact mechanism: The anchor device of the present invention allows tensile and shear deformation to occur instantaneously, which greatly improves the single fixing defect of traditional anchors and can effectively prevent or reduce the impact of impact ground pressure.

[0018] 3. Composite performance application: The present invention combines initial anchoring with later grouting, which can realize the combination of in-situ modification technology and energy-absorbing support method, greatly improve the stability of the rock mass, and help to improve the mechanical properties of the in-situ rock mass, creating a more stable and safe tunnel environment for the rock mass to be supported.

[0019] 4. Coping with extreme conditions: In environments where impact ground pressure is frequent or particularly strong, traditional support methods are difficult to cope with. The material of the anchor rod described in the present invention (NPR material / exotic metal material) can adapt to extreme geological conditions, including but not limited to temperature, earthquake, blasting disturbance, rock burst, landslide, etc. Description of the drawings: Figure 1 It is a schematic diagram of the main structure of an embodiment of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the expansion sleeve of the present invention; Figure 3 It is a schematic diagram of the three-dimensional structure of the constant resistance sleeve of the present invention; Figure 4 is a schematic diagram of the main structure of another embodiment of the present invention; Figure 5 , 6 yes Figure 4 A partial view of the . Specific implementation method: The impact-resistant composite grouting anchor of the present invention comprises an anchor 2 having a central channel 1 and a spacer 3 arranged in the central channel of the anchor. The spacer can be a spacer fixed at one-third to one-half of the central channel of the anchor. The spacer can be fixed in the central channel by glue, etc., or another method of fixing can be provided later.

[0022] The first end of the anchor rod 2 is sleeved with an expansion sleeve 4. When the anchor rod is pressed against the expansion sleeve, the outer circumference of the expansion sleeve expands. Specifically, the inner circumferential wall of the expansion sleeve 4 is conical, and the first end of the anchor rod is also conical (the first end face of the anchor rod is closed). The large ends of the cones are all facing the second end of the anchor rod, and a plurality of grooves 12 are evenly distributed in the circumferential direction of the expansion sleeve on the side facing the second end of the anchor rod. When the anchor rod is pressed against the expansion sleeve, the outer circumference of the expansion sleeve is easily expanded due to the provision of the grooves 12. When the expansion sleeve 4 and the anchor rod 2 are inserted into the hole drilled in the rock, as the second end of the anchor rod 2 is knocked, the anchor rod 2, the expansion sleeve 4 and the drilled hole can be more tightly clamped.

[0023] A plurality of through holes 5 are arranged on the anchor rod 2 between the first end and the partition plate, and the through holes 5 are used to pass concrete slurry, water, etc. from the central channel.

[0024] A limiting groove 6 is provided in the anchor rod near the partition. The limiting groove is conical. An anchor joint 7 is placed in the limiting groove. The anchor joint is also conical in shape to match the cone.

[0025] The anchor joint 7 is connected to a prestressed tube 8, the right end of which passes through the second end of the anchor rod. The anchor joint is coaxially arranged with the prestressed tube and is fixed by threaded connection or welding. The limiting groove 6 is formed by a conical bucket 17 fixed in the central channel of the anchor rod. The large end of the conical bucket is welded to the inner wall of the central channel of the anchor rod, and the small end of the conical bucket is welded to a sleeve 16, and the center of the sleeve is used to pass the prestressed tube 8.

[0026] The right end of the prestressed pipe 8 is provided with a thread and a nut 9 connected to the thread, and a baffle 10 is abutted between the nut 9 and the second end of the anchor rod 2. When the nut is tightened, the prestressed pipe 8 is tightened between the anchor joint 7 and the baffle 10. A feed pipe 11 that can pass through the spacer is provided in the center hole of the prestressed pipe. The feed pipe can be a plastic pipe, a first end of which passes through the spacer, and a second end of which passes through the right end of the prestressed pipe. Concrete slurry or water is introduced into the right end of the feed pipe 11, and the left end of the feed pipe 11 passes through the spacer 3. After the concrete slurry or water is introduced, it overflows from the through hole 5.

[0027] In one embodiment, the anchor rod 2 is separated into two pipe rods at the position where the spacer is installed. The two pipe rods are fixed by threaded connection at one end close to each other. The spacer is pressed at the bottom of the threaded groove 13 of the first pipe rod and at the end face of the second pipe rod. That is, the spacer is first abutted against the end face of the second pipe rod, and then the two pipe rods are screwed together, thereby realizing the tightening and fixation of the two pipe rods and the fixation of the spacer. The large end of the conical bucket 17 is welded and fixed in the central channel close to the end face of the second pipe rod.

[0028] The anchor rod 2 is divided into two pipe rods at the location where the spacer is installed, which not only facilitates the installation of the spacer, but also facilitates the welding and fixing of the large end of the conical bucket 17 in the central channel close to the end face of the second pipe rod.

[0029] The outer periphery of the above-mentioned anchor rod is provided with a constant resistance sleeve 14 made of NPR material or exotic metal material, and the constant resistance sleeve is evenly distributed with groove joints 15 on both ends of the circumference, and the grooves at both ends are staggered in the circumferential direction. The inner circumferential wall of the constant resistance sleeve 14 and the outer circumferential wall of the anchor rod can also be a conical matching connection like the inner circumferential wall of the expansion sleeve 4 and the outer circumferential wall of the anchor rod 2.

[0030] In addition, the composite grouting anchor rod of the present invention can also be used in the construction of preventing rock burst: As a geological disaster phenomenon, rockbursts pose a serious threat to mine safety due to their suddenness and destructiveness. In deep mining activities, due to the concentrated release of ground stress, rocks are ejected instantly, which not only endangers the lives of miners, but also may cause equipment damage and production interruptions, resulting in huge economic losses; therefore, the importance of rockburst control cannot be ignored. Effective control measures can significantly reduce the frequency and intensity of rockbursts, provide miners with a safe working environment, and ensure the smooth mining of mineral resources. In addition, with the deepening of resource development, rockburst problems have become increasingly prominent, and strengthening rockburst control has become the key to improving the economic benefits of mines and achieving sustainable development.

[0031] As an advanced geological engineering technology, hydraulic fracturing has demonstrated unique effectiveness in preventing rock bursts. This method uses high-pressure water flow to pre-crack rocks to reduce the rigidity of the rock mass and release internal stress, thereby effectively reducing the possibility of rock bursts. In high-risk areas such as deep mining, hydraulic fracturing can improve the stress state of rocks and make them develop in a direction that is conducive to stability. Specifically, it controls the generation and expansion of cracks, disperses stress concentration areas, and reduces the risk of rock bursts caused by excessive stress concentration.

[0032] The composite grouting anchor rod of the present invention can achieve the effect of rock burst control through the construction method of "one-step water injection and two-step grouting". The specific construction steps are as follows: (5) Apply prestress to the anchor rod. After the anchor rod 2 and the expansion sleeve 4 are placed in the borehole, the feed pipe 11 is passed through the retaining plate 10 and the prestressing pipe 8, and the nut is rotated to apply prestress. Generally speaking, the selection of the anchor rod preload should follow certain principles, such as the surrounding rock does not have obvious delamination, sliding and tensile stress. It is usually recommended that the anchor rod preload be about 30% of the yield load of the anchor rod body. (6) High-pressure water injection: high-pressure water is injected along the grouting port (the right end port of the feed pipe 11). The high-pressure water is injected into the high-stress rock mass through the through hole 5, and the liquid pressure is used to open and expand the cracks in the rock. By controlling the formation and expansion of the cracks, the purpose of releasing the ground stress is achieved; (7) Stress release of high-risk rock mass. After high-pressure water is injected, a constant water injection pressure must be maintained. The maintenance time is determined according to the rock mass conditions. Generally speaking, the greater the rock burst tendency, the longer the stable water injection time is maintained. During the fracture process, the water pressure will exceed the tensile strength of the rock, causing the rock to break. (8) Pumping out pressure. After the high-pressure water has fully exerted its effect and caused the rock mass to rupture, a pumping device (water pump) is used to completely drain out the fissure water injected into the rock mass. This pumping process not only helps to further reduce the internal stress of the rock mass, but also forms a fissure development zone around the anchor rod, creating favorable conditions for the grouting of the anchor rod. By pumping out pressure, the stress state of the rock mass can be effectively adjusted and improved, providing a guarantee for the stability of the rock mass. At the same time, this method also helps to improve the permeability of the rock mass, providing convenience for possible drainage, thereby reducing the risk of rock burst caused by water pressure to a certain extent.

[0033] (9) Grouting reinforcement: To further enhance the anchor reinforcement effect, after pumping out the pressure, a slurry (concrete slurry) with a specific ratio is injected into the feed pipe through the grouting port. As the slurry is injected and penetrates, it gradually fills the cracks and voids in the rock mass, forming an integrated anchoring structure with the anchor.

[0034] The above-mentioned "one-step water injection and two-step grouting" of the present invention is a construction plan based on areas where rock bursts frequently occur. When installing anchor rods, the anchor rod body collides with the surrounding rock mass, causing a plastic zone to be generated in the rock mass around the anchor rod, accompanied by the distribution of microcracks; when encountering a high stress concentration area, the crack expansion range is wider, which provides a good foundation for improving the penetration of high-pressure water; the rock burst prevention and control mechanism described in the present invention has two aspects: one is that the anchor rod body collides with the surrounding rock mass, causing a plastic zone to be generated in the rock mass around the anchor rod, and the anchor rod drilling provides a stress release space for the high stress area of ​​rock burst; the second is that the injection pressure of high-pressure water further expands the distribution space of the liquid, expands the rock burst prevention and control area, and improves the rock burst prevention and control effect; the third is that pumping water to unload pressure provides a buffer space for the rock mass, so as to reduce the rigidity of the rock mass and release internal stress, thereby effectively reducing the possibility of rock burst.

[0035] The above-mentioned constant resistance sleeve 14 adopts NPR material or exotic metal material. NPR material is a new type of metamaterial with special mechanical properties. It exhibits unique physical properties, that is, when subjected to uniaxial tension or compression, it does not undergo lateral contraction according to the conventional Poisson's ratio effect, but produces lateral expansion. The purpose of using NPR material in the present invention is to prevent diametrical contraction, withstand certain deformation, and provide constant resistance; exotic metal material is a kind of material with unconventional physical properties. They exhibit different behaviors from traditional metals in terms of electron transport, magnetism and superconductivity, and achieve both the ultra-high flexibility of polymer materials and the ultra-high strength of ultra-high strength steel, while being able to remain unchanged in a wide temperature range of -80°C to +80°C.

[0036] The production of each component of the present invention: (1) preparing a constant resistance sleeve, wherein the constant resistance sleeve is prepared using NPR material / exotic metal material, and both sides of the constant resistance sleeve are pre-cut to form a groove joint 15, so that the diameter length of both sides of the constant resistance sleeve is slightly larger than the original diameter; (2) Preparation of an anchor rod structure, wherein the anchor rod structure includes: a rod body, a stop plate, a prestressed nut, a spacer, a feed pipe, a prestressed pipe, an expansion sleeve, and a constant resistance sleeve.

[0037] A. The rod body is divided into two parts by a spacer. The distance between the spacer and the end of the anchor rod is 1 / 3 to 1 / 2 of the length of the anchor rod. A small hole is preset in the middle of the spacer for the grouting pipe (feeding pipe) to pass through to achieve the grouting effect.

[0038] B. A small hole with a circular center is preset in the middle of the retaining plate, and the thickness of the retaining plate is 3-5 cm. During construction, the retaining plate is placed between the rod body and the nut to apply prestress to the anchor rod.

[0039] C. The nut is connected to the retaining plate and is used to apply prestress to the anchor rod. The prestress is applied to the anchor rod by tightening the nut.

[0040] (3) Before anchor construction, an expansion sleeve is placed at the end of the anchor. The diameter of one side of the expansion sleeve remains unchanged, and the pipe seam is pre-cut on the other side so that the diameter of the cut side is slightly larger than that of the uncut side.

[0041] (4) The anchor rod body is placed in the reinforced rock mass. When the end of the anchor rod is squeezed by the expansion sleeve, the end and the rock mass form an extrusion stress, achieving a preliminary anchoring effect.

[0042] (5) After the anchor rod body is anchored, the constant resistance deformation sleeve is placed along the rod body at the fixed position of the constant resistance sleeve to allow for subsequent constant resistance deformation.

[0043] (6) The retaining plate and nut provide prestressing. The retaining plate is inserted into the prestressing tube to contact the rod body, and the nut is rotated to apply prestressing to further enhance the anchoring effect.

[0044] (7) Grouting is carried out along the grouting port into the feed pipe to form an integrated anchoring structure.

[0045] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A composite grouting anchor rod resistant to impact damage, characterized in that: It includes an anchor rod with a central channel and a partition arranged in the central channel of the anchor rod, the first end portion of the anchor rod is sleeved with an expansion sleeve, and the outer periphery of the expansion sleeve expands when the anchor rod is pressed against the expansion sleeve, and a plurality of through holes are arranged on the anchor rod at a position between the first end and the partition, and a limiting groove is provided in the anchor rod near the partition, and an anchor joint is accommodated in the limiting groove, and the anchor joint is connected to a prestressed tube with a right end passing through the second end of the anchor rod, the right end of the prestressed tube is provided with a thread and a nut connected to the thread, a stop plate is abutted between the nut and the second end of the anchor rod, and a feed pipe that can pass through the partition is provided in the central hole of the prestressed tube.

2. The impact-resistant composite grouting anchor according to claim 1 is characterized in that: The limiting groove is in a cone shape, and the anchor joint is also in a cone shape matching the cone.

3. The impact-resistant composite grouting anchor according to claim 1 is characterized in that: The spacer is a spacer, which is fixed at one-third to one-half of the central channel of the anchor rod.

4. The impact-resistant composite grouting anchor according to claim 1, 2 or 3, characterized in that: The inner wall of the expansion sleeve is conical, the first end of the anchor rod is also conical, the large end of the cone faces the second end of the anchor rod, and a plurality of slots are arranged in the circumferential direction on the side of the expansion sleeve facing the second end of the anchor rod.

5. The impact-resistant composite grouting anchor according to claim 4 is characterized in that: The anchor joint is coaxially arranged with the prestressed pipe and is fixed by threaded connection or welding.

6. The impact-resistant composite grouting anchor according to claim 1, characterized in that: The limiting groove is formed by a conical bucket fixed in the central channel of the anchor rod, the large end of the conical bucket is welded to the inner wall of the central channel of the anchor rod, and the small end of the conical bucket is welded to a sleeve, and the center of the sleeve is used to pass the prestressed pipe.

7. The impact-resistant composite grouting anchor according to claim 6 is characterized in that: The anchor rod is divided into two pipe rods at the position where the spacer is installed. The two pipe rods are fixed by threaded connection at one end close to each other. The spacer is pressed on the bottom of the threaded groove of the first pipe rod and on the end face of the second pipe rod. The conical bucket is welded and fixed in the central channel close to the end face of the second pipe rod.

8. The impact-resistant composite grouting anchor according to claim 7, characterized in that: The material delivery pipe is a plastic pipe, a first end of which passes through the spacer, and a second end of which passes through the right end of the prestressed pipe.

9. A construction method of a composite grouting anchor rod resistant to impact damage as claimed in any one of claims 1 to 8, characterized in that: First, drill a hole in the rock, put the expansion sleeve on the anchor rod and then insert it into the drill hole. During the insertion process, the force applied to the anchor rod causes the expansion sleeve to expand and be fastened to the drill hole. Then, rotate the nut to make the anchor joint approach the second end of the anchor rod, so as to further pre-tighten the anchor joint to the limiting groove and the anchor rod. Then, pour concrete slurry into the central channel of the anchor rod through the feed pipe. The slurry overflows from the through hole into the drill hole. After the slurry solidifies, the anchor rod is fixed.

10. An application of the impact-resistant composite grouting anchor rod according to any one of claims 1 to 8 in preventing rock bursts, characterized in that: Apply prestress to the anchor rod. After the anchor rod 2 and the expansion sleeve 4 are placed in the borehole, the conveying pipe 11 is passed through the retaining plate 10 and the prestressing pipe 8, and the nut is rotated to apply prestress. High-pressure water injection: high-pressure water is injected along the right end of the conveying pipe 11, and the high-pressure water is injected into the high-stress rock mass through the through hole 5, and the liquid pressure is used to open and expand the cracks in the rock, and the purpose of releasing the ground stress is achieved by controlling the formation and expansion of the cracks; High-risk rock mass stress release, after high-pressure water injection, constant water injection pressure must be maintained; Pumping to relieve pressure, after the high-pressure water has fully exerted its effect and caused the rock mass to fracture, use the pumping device to completely drain the fissure water injected into the rock mass; Grouting reinforcement, after completing the pumping and pressure relief, concrete slurry is injected into the feed pipe through the right end port of the feed pipe 11; with the injection and penetration of the slurry, the slurry gradually fills the cracks and voids in the rock mass, forming an anchoring integrated structure with the anchor rod.

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