Device and method for repairing surrounding rock of soft rock water-containing roadway

Abstract

The invention relates to the technical field of soft rock roadway repairing, in particular to a soft rock water-containing roadway surrounding rock repairing device and method.The method comprises the following steps that a roadway is shaped, brushing and expanding treatment is conducted on an unstable roadway, and a regular new section is formed; constructing a hydrophobic diversion system, wherein the hydrophobic diversion system comprises deep hydrophobic holes and a surface water diversion grid; anchoring support and grouting reinforcement are conducted, anchor holes are drilled, anchor rods are anchored in the anchor holes so as to support the surrounding rock of the roadway, and pressurized grouting is conducted on the anchor holes where the anchor rods are anchored so that the surrounding rock can form a bearing reinforcing ring and an annular water-resisting layer; and performing dynamic reinforcement, monitoring the repaired roadway, identifying a key area with stress concentration and abnormal deformation based on the deformation condition of the roadway, and performing reinforcement support on the key area. According to the scheme, the weakening effect of water on soft rock and erosion of water on a support body are eliminated in a mode of combining anchoring support, grouting reinforcement of surrounding rock, formation of a water-resisting layer, deep dewatering and shallow water guide, and the stability of a roadway is effectively controlled.

Description

Technical Field

[0001] This invention relates to the field of soft rock tunnel repair technology, specifically to a device and method for repairing the surrounding rock of a soft rock water-bearing tunnel. Background Technology

[0002] As coal mines move into deeper levels, deep mining is subject to the negative geological environment of "three highs and one disturbance"—high stress, high temperature, high gas, and strong disturbance—compared to shallow mines, increasing the difficulty of roadway support. Water-bearing roadways are becoming increasingly common in deep mines. Due to the complex interaction mechanism between groundwater and rock mass, the deformation and failure mechanism of water-bearing roadways is far more complex than that of ordinary roadways. This is because, under the long-term erosion of water, and with the presence of components such as kaolinite, the rock mass is prone to expansion, softening, and disintegration, leading to a decrease in the strength of the surrounding rock. Existing technologies, such as conventional anchor bolt support, cannot form a water-resistant layer or guide the flow of water in the surrounding rock. This results in residual water pressure and seepage continuously weakening the surrounding rock. Furthermore, traditional rigid supports are difficult to adapt to the large deformation characteristics of soft rock and are easily crushed. Additionally, there are problems such as poor anchoring force of anchoring agents and easy corrosion of metal support bodies such as anchor bolts and cables, requiring repeated roadway repairs and failing to fundamentally solve the problem of supporting water-bearing roadways in soft rock. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a device and method for repairing the surrounding rock of soft rock water-bearing tunnels, which solves the problem mentioned in the background art that the existing traditional anchoring support cannot effectively solve the problem of the continuous weakening of the surrounding rock by residual water pressure and seepage, the poor anchoring force, and the easy corrosion of metal support bodies such as anchor bolts and anchor cables, which makes the tunnels need to be repaired repeatedly, and cannot solve the problem of support for soft rock water-bearing tunnels.

[0004] To solve the above-mentioned technical problems, the first aspect of the present invention provides a method for repairing the surrounding rock of a water-bearing soft rock tunnel, comprising the following steps: Step S10: Roadway shaping. The unstable roadway is brushed and widened to thoroughly clean up the broken surrounding rock and failed support components around the roadway, forming a regular new cross-section. Step S20: Construct a drainage system, including deep drainage holes and surface drainage grids. The deep drainage holes guide deep water to the drainage ditch in the tunnel, and the surface drainage grids are used to guide seepage water from the shallow surrounding rock to the drainage ditch in the tunnel.

[0005] Step S30: Perform anchoring support and grouting reinforcement. Design several anchoring points and drill anchor holes in the direction of the surrounding rock deep in the roadway. Anchor the constant resistance and pressure relief anchor rod in the anchor hole to support the surrounding rock of the roadway. Then, pressurize and grout the anchor hole where the constant resistance and pressure relief anchor rod is anchored to fully anchor the constant resistance and pressure relief anchor rod. Under pressure, the grout penetrates into the fissures of the surrounding rock mass, cementing the broken soft rock into a whole and forming an annular water-proof layer with load-bearing reinforcement and water-proofing functions. Step S40: Perform dynamic reinforcement, monitor the repaired roadway, identify key areas of stress concentration and abnormal deformation based on the roadway deformation, and reinforce and support these key areas.

[0006] Furthermore, in step S10, an early-strength concrete layer is sprayed onto the roadway wall after brushing and widening to form an initial spray layer.

[0007] Furthermore, in step S20, the deep drainage holes are drilled at an angle at the bottom of both sides of the roadway, and the surface water guiding grid includes a water guiding groove distributed in a mesh pattern recessed on the surface of the initial sprayed layer and a permeable pipe set in the water guiding groove. The deep drainage holes and the permeable pipe in the water guiding groove guide the surrounding rock water to the drainage ditch on the roadway surface.

[0008] Furthermore, in step S30, after drilling anchor holes according to the designed spacing, the medicated anchoring agent is placed into the anchor holes, and the medicated anchoring agent is pushed to the bottom of the anchor holes through the anchor rod. Then, the anchor hole drilling machine rotates and stirs the medicated anchoring agent through the anchor rod to achieve end anchoring of the anchor rod.

[0009] Furthermore, in step S40, the reinforcement support includes deep and shallow hole coupled grouting and steel mesh shotcrete support, wherein shallow hole grouting is used to seal the internal fissures of shallow surrounding rock and consolidate the annular water-proof layer, deep hole grouting is used to reinforce the deep fracture zone, expand the load-bearing structure and block the water source, and steel mesh shotcrete is used to seal the surrounding rock and maintain the integrity of the broken surrounding rock mass on the surface of the roadway.

[0010] In another aspect, the present invention provides a device for repairing the surrounding rock of a water-bearing soft rock tunnel, comprising an anchor rod, a grouting pipe, a constant resistance pressure-relief mechanism sleeved on the anchor rod, and an anchoring assembly. One end of the anchor rod is located inside the anchor hole, and the other end of the anchor rod extends outside the anchor hole. The anchor rod outside the anchor hole is provided with external threads. The anchoring assembly includes a tray and a locking nut. The tray is located at the opening of the anchor hole and is pressed against the tunnel wall. The constant resistance pressure-relief mechanism includes a constant resistance sleeve, a pressure-relief seat, and a pressure-relief ring coaxially arranged with the anchor rod. The constant resistance sleeve is a circular cylinder with one open end, disposed inside the anchor hole, with the open end facing the tunnel direction. There is a gap between the outer wall of the constant resistance sleeve and the inner wall of the anchor hole. The inner wall of the constant resistance sleeve is provided with internal threads. There is a gap between the anchor rod and the inner wall of the constant resistance sleeve. The tray is provided with a second through hole that mates with the constant resistance sleeve. The open end of the constant resistance sleeve is inserted into the second through hole and is sealed and fixedly connected to it. The pressure relief seat is located outside the anchor hole. The pressure relief seat is a frustum-shaped body that is sleeved on the anchor rod and slidably connected to it. The small end of the pressure relief seat faces the depth of the anchor hole. The outer diameter of the large end of the pressure relief seat is smaller than the inner diameter of the constant resistance sleeve. The pressure relief ring is a ring-shaped body made of plastic metal. The outer diameter of the pressure relief ring is larger than the inner diameter of the constant resistance sleeve. The pressure relief ring is sleeved on the conical surface of the pressure relief seat and is fixedly connected to it. The locking nut is located on the anchor rod near the roadway side of the pressure relief seat and is threadedly connected to it. The inner end of the grouting pipe extends into the bottom of the anchor hole along the gap between the constant resistance sleeve and the inner wall of the anchor hole. The outer end of the grouting pipe passes through the tray and extends out of the anchor hole.

[0011] Furthermore, the anchor bolt includes a steel strand located in the anchor hole and a cylindrical body coaxially and fixedly connected to the steel strand. One end of the steel strand located in the anchor hole is a compression anchoring end. The end of the cylindrical body near the steel strand is set as a cylindrical section, and the end of the cylindrical body away from the steel strand is set as an external threaded section. The outer diameter of the locking nut is smaller than the outer diameter of the pressure relief seat, and the locking nut is threadedly engaged with the external threaded section.

[0012] Furthermore, the closed end of the constant resistance sleeve is provided with a through hole for the anchor rod to pass through, and the outer wall of the closed end of the constant resistance sleeve is provided with an elastic sealing cup for preventing slurry from entering the inner cavity of the constant resistance sleeve. One end of the elastic sealing cup is sealed and fixedly connected to the outer wall of the closed end of the constant resistance sleeve, and the other end of the elastic sealing cup is sleeved on the outside of the anchor rod. The outer wall of the constant resistance sleeve is provided with a groove for increasing the friction between the constant resistance sleeve and the solidified slurry.

[0013] Furthermore, a sealing gasket is provided between the tray and the wall of the tunnel, and the grouting pipe is sealed to the tray.

[0014] Furthermore, the hardness of the materials used to prepare the constant resistance sleeve and the pressure relief seat is higher than the hardness of the materials used to prepare the pressure relief ring.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: 1. In this scheme, by combining anchoring support, grouting to strengthen the surrounding rock, forming a water-proof layer, deep drainage and shallow water conduction, the surrounding rock is strengthened and the water in the surrounding rock is actively drained and passively blocked, which fundamentally eliminates the weakening effect of water on soft rock and the erosion of the support, and effectively controls the stability of the roadway.

[0016] 2. In this solution, the durability and reliability of the repair effect are significantly improved through subsequent monitoring and dynamic reinforcement.

[0017] 3. This solution strengthens the anchoring force and increases the support capacity of the anchor by installing flexible anchors with pressure-yielding characteristics and grouting the entire length of the anchors. Grouting also enhances the bearing capacity of the surrounding rock and avoids brittle failure of the support structure.

[0018] 4. In this scheme, the deformation energy of the surrounding rock is continuously dissipated through the plastic deformation of the constant resistance pressure relief mechanism. When the shallow surrounding rock near the roadway moves towards the roadway and deforms, the constant resistance pressure relief mechanism protects the anchor rod from damage to the overall structure of the anchor rod through plastic deformation. The anchor rod still has the load-bearing capacity and continues to provide support.

[0019] 5. In this solution, the anchor rod is protected by grout, which can effectively prevent the exposed rod from being damaged by corrosion.

[0020] 6. The anchor bolts in this scheme are mainly made of steel stranded rope, and their length is not limited, making them convenient for storage and construction in tunnels. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of the application and are used to explain the application, but do not constitute an undue limitation of the application. In the drawings: Figure 1 This is a schematic diagram of the repaired tunnel structure.

[0022] Figure 2 This is a schematic diagram of the structure of the soft rock water-bearing roadway surrounding rock repair device of the present invention when the roadway has not deformed.

[0023] Figure 3 This is a schematic diagram of the structure of the soft rock water-bearing roadway surrounding rock repair device of the present invention when the roadway deforms.

[0024] The meanings of the labels in the attached diagram are as follows: Tunnel-10; Deep drainage hole-101; Drainage ditch-102; Initial shotcrete layer-103; Annular waterproof layer -20; Anchor hole -30; Anchor bolt - 40; Steel strand - 401; Cylindrical section - 4021; External thread section - 4022; Tray - 41; Through hole two - 411; Locking nut - 42; Constant resistance sleeve - 431; Groove - 4311; Through hole one - 4312; Pressure relief seat - 432; Pressure relief ring - 433; Elastic sealing cup - 44; Grouting pipe-50. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0027] In one specific implementation plan, combined with Figure 1 As shown, the present invention provides a method for repairing a soft rock water-bearing tunnel 10, comprising the following steps: Step S10: Roadway shaping. The unstable roadway 10 is brushed and widened to thoroughly clean the broken surrounding rock and failed support components around the roadway 10, forming a regular new cross-section. Step S20: Construct a drainage system, including deep drainage holes 101 and surface drainage grid. The deep drainage holes 101 guide deep water to the drainage ditch 102 in the tunnel 10, and the surface drainage grid is used to guide seepage water from the shallow surrounding rock to the drainage ditch 102 in the tunnel 10.

[0028] Step S30: Perform anchoring support and grouting reinforcement. Design several anchoring points and drill anchor holes 30 at the anchoring points towards the surrounding rock deep in the tunnel 10. Anchor the constant resistance and pressure relief anchor rod 40 to the anchor hole 30 to support the surrounding rock of the tunnel 10. Then, pressurize and grout the anchor hole 30 where the constant resistance and pressure relief anchor rod 40 is anchored to fully anchor the constant resistance and pressure relief anchor rod 40. Under pressure, the grout penetrates into the fissures of the surrounding rock mass, cementing the broken soft rock into a whole to form an annular water-proof layer 20 with load-bearing reinforcement and water-proofing functions. Step S40: Perform dynamic reinforcement. Monitor the repaired roadway 10. Based on the deformation of roadway 10, identify key areas of stress concentration and abnormal deformation, and reinforce and support these key areas.

[0029] In step S10, an early-strength concrete layer is sprayed onto the wall of the 10 tunnel after it has been brushed and shaped to form an initial spray layer 103.

[0030] In step S20, the deep drainage holes 101 are drilled at an angle at the bottom of both sides of the tunnel 10. The surface water guiding grid includes a water guiding groove distributed in a mesh pattern recessed on the surface of the initial sprayed layer 103 and a permeable pipe set in the water guiding groove. The deep drainage holes 101 and the permeable pipe in the water guiding groove guide the surrounding rock water to the drainage ditch 102 on the ground of the tunnel 10.

[0031] In step S30, after drilling anchor holes 30 according to the designed spacing, the medicated anchoring agent is placed into the anchor holes 30. The medicated anchoring agent is pushed to the bottom of the anchor holes 30 through the anchor rod 40. Then, the end of the anchor rod 40 is anchored by rotating and stirring the medicated anchoring agent through the anchor hole 30 drilling machine.

[0032] In step S40, the reinforcement support includes deep and shallow hole coupled grouting and steel mesh shotcrete support. The shallow hole grouting is used to seal the internal cracks of the shallow surrounding rock and consolidate the annular water-proof layer 20. The deep hole grouting is used to reinforce the deep fracture zone, expand the load-bearing structure and block the water source. The steel mesh shotcrete is used to seal the surrounding rock and maintain the integrity of the broken surrounding rock mass on the surface of the roadway 10.

[0033] In a specific implementation plan, such as Figures 2-3 As shown, this invention provides a device for repairing surrounding rock in soft rock aquifer tunnels, including an anchor rod 40, a grouting pipe 50, a constant resistance pressure-relieving mechanism sleeved on the anchor rod 40, and an anchoring assembly. One end of the anchor rod 40 is located inside the anchor hole 30, and the other end of the anchor rod 40 extends outside the anchor hole 30. The anchor rod 40 outside the anchor hole 30 is provided with external threads. Specifically, the anchor rod 40 includes a steel strand 401 located inside the anchor hole 30 and a cylindrical body coaxially and fixedly connected to the steel strand 401. The end of the steel strand 401 located inside the anchor hole 30 is a compression anchoring end. The end of the cylindrical body near the steel strand 401 is set as a smooth cylindrical section 4021, and the end of the cylindrical body away from the steel strand 401 is set as an externally threaded section 4022. The steel strand 401 and the cylindrical body can be fixedly connected together by hot forging. Due to the special structure of this embodiment, the anchor rod 40 can be pre-prepared in the factory according to the designed depth of the anchor hole 30.

[0034] The anchoring assembly includes a tray 41 and a locking nut 42. The tray 41 is located at the opening of the anchor hole 30 and is pressed against the wall of the tunnel 10. An annular sealing gasket is provided between the tray 41 and the wall of the tunnel 10 to prevent the grout in the anchor hole 30 from overflowing.

[0035] The constant resistance relief mechanism includes a constant resistance sleeve 431, a relief seat 432, and a relief ring 433 coaxially arranged with the anchor bolt 40. The constant resistance sleeve 431 is a cylindrical body with one open end disposed in the anchor hole 30, with the open end of the constant resistance sleeve 431 facing the roadway 10. There is a gap between the outer wall of the constant resistance sleeve 431 and the inner wall of the anchor hole 30. The inner wall of the constant resistance sleeve 431 is provided with internal threads. The closed end of the constant resistance sleeve 431 is provided with a through hole 4312 for the cylindrical section 4021 of the anchor bolt 40 to pass through. The outer wall of the closed end of the constant resistance sleeve 431 is provided with an elastic sealing cup for preventing slurry from entering the inner cavity of the constant resistance sleeve 431. The elastic sealing cup is coaxially arranged with the through hole 4312. One end of the elastic sealing cup is sealed and fixedly connected to the outer wall of the closed end of the constant resistance sleeve 431, and the other end of the elastic sealing cup is fitted tightly onto the outer wall of the cylindrical section 4021. The outer wall of the constant resistance sleeve 431 is provided with a groove 4311 for increasing the friction between the constant resistance sleeve 431 and the solidified slurry. The tray 41 is provided with a through hole 411 that cooperates with the constant resistance sleeve 431. The open end of the constant resistance sleeve 431 is inserted into the through hole 411 and sealed and fixedly connected to the through hole 411. Specifically, the constant resistance sleeve 431 and the tray 41 can be fixedly connected by welding. There is a gap between the cylindrical section 4021 of the anchor rod 40 and the inner wall of the constant resistance sleeve 431.

[0036] The pressure relief seat 432 is disposed outside the anchor hole 30. The pressure relief seat 432 is a frustum-shaped body that is sleeved on the cylindrical body of the anchor rod 40 and slidably connected to the cylindrical body. The small end of the pressure relief seat 432 faces the depth of the anchor hole 30. The outer diameter of the large end of the pressure relief seat 432 is smaller than the inner diameter of the constant resistance sleeve 431. The gap between the outer wall of the large end of the pressure relief seat 432 and the inner wall of the constant resistance sleeve 431 is set to be 2 to 8 mm. The locking nut 42 is located on the external thread section 4022 of the pressure relief seat 432 near the roadway 10 and is threadedly connected to the external thread section 4022. The outer diameter of the locking nut 42 is smaller than the outer diameter of the pressure relief seat 432. The pressure relief ring 433 is a ring-shaped body made of ductile metal. The outer diameter of the pressure relief ring 433 is larger than the inner diameter of the constant resistance sleeve 431. The pressure relief ring 433 is sleeved on the conical surface of the pressure relief seat 432 and fixedly connected to the pressure relief seat 432. Specifically, the hardness of the materials used to make the constant resistance sleeve 431 and the pressure relief seat 432 is higher than the hardness of the materials used to make the pressure relief ring 433. Preferably, the pressure relief ring 433 is made of brass, such as H62 or H68. Brass has good plasticity and ductility, which is beneficial for providing stable deformation resistance. The constant resistance sleeve 431 and the pressure relief seat 432 are made of 45 steel. To prevent the pressure relief ring 433 from being sheared by the inner edge of the opening end of the constant resistance sleeve 431, the inner edge of the opening end of the constant resistance sleeve 431 is set as an arc chamfer.

[0037] The inner end of the grouting pipe 50 extends into the bottom of the anchor hole 30 along the gap between the constant resistance sleeve 431 and the inner wall of the anchor hole 30. The outer end of the grouting pipe 50 passes through the tray 41 and extends out of the anchor hole 30. The grouting pipe 50 is sealed to the tray 41. After the grouting of the anchor hole 30 is completed, the grouting pipe 50 remains inside the anchor hole 30.

[0038] In use, the device first places the cartridge-type anchoring agent into the anchor hole 30. The anchor rod 40 pushes the cartridge-type anchoring agent to the bottom of the anchor hole 30. Then, the anchor hole 30 drilling machine rotates and stirs the anchor rod 40 to anchor the end of the anchor rod 40. After the anchor rod 40 is anchored to the anchor hole 30, the constant resistance sleeve 431, the pressure relief seat 432, and the locking nut 42 are sequentially placed on the cylindrical body. The anchor rod 40 is pulled by the pulling equipment to bring it into a pre-tightened state and reach the preset pre-tightening force. The locking nut 42 is turned by the torque wrench to make the pressure relief ring 433 on the pressure relief seat 432 press against the open end of the constant resistance sleeve 431, so that the pre-tightening force of the anchor rod 40 acts on the tray 41. According to the design, under the set pre-tightening force, the pressure relief ring 433 will not be squeezed and deformed. The grouting pipe 50 is passed through the tray 41 and inserted into the bottom of the anchor hole 30. The grouting pipe 50 and the tray 41 are sealed with sealant. Then, the grouting machine is used to pressurize and grout into the anchor hole 30 through the grouting pipe 50. After the grouting is completed, the grouting pipe 50 remains in the anchor hole 30.

[0039] When the shallow surrounding rock of tunnel 10 deforms and moves in the direction of tunnel 10, such as Figure 3 As shown, the constant resistance sleeve 431 moves towards the roadway 10 along with the shallow surrounding rock, causing the pressure seat 432 to move towards the depth of the anchor hole 30 relative to the constant resistance sleeve 431. This gradually reduces the gap between the conical surface of the pressure seat 432 and the inner wall of the constant resistance sleeve 431, causing the pressure ring 433 to deform. The internal thread on the inner wall of the constant resistance tube prevents the pressure ring 433 from sliding relative to the inner wall of the constant resistance tube. Therefore, the plastic deformation of the pressure ring 433 results in a constant resistance to the anchor rod 40. Because the pressure and constant resistance are provided, the anchor rod 40 will not be forcibly broken when the surrounding rock moves and deforms, and it will continue to provide support to the surrounding rock of the roadway 10.

[0040] The above are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics in the solutions is not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A soft rock water-containing roadway surrounding rock repairing method, characterized in that, Includes the following steps: Step S10: Roadway shaping. The unstable roadway is brushed and widened to thoroughly clean up the broken surrounding rock and failed support components around the roadway, forming a regular new cross-section. Step S20: Construct a drainage system, including deep drainage holes and surface drainage grids. The deep drainage holes guide deep water to the drainage ditch in the tunnel, and the surface drainage grids are used to guide seepage water from the shallow surrounding rock to the drainage ditch in the tunnel. Step S30: Perform anchoring support and grouting reinforcement. Design several anchoring points and drill anchor holes in the direction of the surrounding rock deep in the roadway. Anchor the constant resistance and pressure relief anchor rod in the anchor hole to support the surrounding rock of the roadway. Then, pressurize and grout the anchor hole where the constant resistance and pressure relief anchor rod is anchored to fully anchor the constant resistance and pressure relief anchor rod. Under pressure, the grout penetrates into the fissures of the surrounding rock mass, cementing the broken soft rock into a whole and forming an annular water-proof layer with load-bearing reinforcement and water-proofing functions. Step S40: Perform dynamic reinforcement, monitor the repaired roadway, identify key areas of stress concentration and abnormal deformation based on the roadway deformation, and reinforce and support these key areas.

2. The soft rock water-containing roadway surrounding rock repairing method according to claim 1, characterized in that: Step S10 also includes spraying a layer of early-strength concrete onto the roadway wall after it has been brushed and shaped to form an initial spray layer.

3. The method for repairing surrounding rock in soft rock water-bearing tunnels according to claim 1, characterized in that: In step S20, the deep drainage holes are drilled at an angle at the bottom of both sides of the tunnel, and the surface water guiding grid includes water guiding channels that are recessed on the surface of the initial sprayed layer and distributed in a mesh pattern, and water permeable pipes are set in the water guiding channels.

4. The method for repairing surrounding rock in soft rock water-bearing tunnels according to claim 1, characterized in that: In step S30, after drilling anchor holes according to the designed spacing, the medicated anchoring agent is placed into the anchor holes. The medicated anchoring agent is pushed to the bottom of the anchor holes through the anchor rod. Then, the anchor hole drilling machine rotates and stirs the medicated anchoring agent through the anchor rod to achieve end anchoring of the anchor rod.

5. The method for repairing surrounding rock in soft rock water-bearing tunnels according to claim 1, characterized in that: In step S40, the reinforcement support includes deep and shallow hole coupled grouting and steel mesh shotcrete support. The shallow hole grouting is used to seal the internal cracks of the shallow surrounding rock and consolidate the annular water-proof layer. The deep hole grouting is used to reinforce the deep fracture zone, expand the load-bearing structure and block the water source. The steel mesh shotcrete is used to seal the surrounding rock and maintain the integrity of the broken surrounding rock mass on the surface of the roadway.

6. A device for repairing surrounding rock in soft rock water-bearing tunnels, comprising anchor bolts, characterized in that: It also includes a grouting pipe, a constant resistance relief mechanism fitted onto the anchor rod, and an anchoring assembly. One end of the anchor rod is located inside the anchor hole, and the other end extends out of the anchor hole. The anchor rod outside the anchor hole has external threads. The anchoring assembly includes a tray and a locking nut. The tray is located at the opening of the anchor hole and is pressed against the roadway wall. The constant resistance relief mechanism includes a constant resistance sleeve, a relief seat, and a relief ring coaxially arranged with the anchor rod. The constant resistance sleeve is a cylindrical body with one open end, set inside the anchor hole, with the open end of the constant resistance sleeve facing the roadway direction. There is a gap between the outer wall of the constant resistance sleeve and the inner wall of the anchor hole. The inner wall of the constant resistance sleeve has internal threads. There is a gap between the anchor rod and the inner wall of the constant resistance sleeve. The tray is provided with a through-hole that mates with the constant resistance sleeve. Hole 2: The open end of the constant resistance sleeve is inserted into the through hole 2 and sealed and fixedly connected to it. The pressure relief seat is set outside the anchor hole. The pressure relief seat is a truncated cone body that is sleeved on the outside of the anchor rod and slidably connected to the anchor rod. The small end of the pressure relief seat faces the depth of the anchor hole. The outer diameter of the large end of the pressure relief seat is smaller than the inner diameter of the constant resistance sleeve. The pressure relief ring is a ring-shaped body made of plastic metal. The outer diameter of the pressure relief ring is larger than the inner diameter of the constant resistance sleeve. The pressure relief ring is sleeved on the conical surface of the pressure relief seat and fixedly connected to it. The locking nut is located on the anchor rod near the roadway side of the pressure relief seat and is threadedly connected to the anchor rod. The inner end of the grouting pipe extends into the bottom of the anchor hole along the gap between the constant resistance sleeve and the inner wall of the anchor hole. The outer end of the grouting pipe passes through the tray and extends out of the anchor hole.

7. The soft rock aquifer roadway surrounding rock repair device according to claim 6, characterized in that: The anchor bolt includes a steel strand located in the anchor hole and a cylindrical body coaxially and fixedly connected to the steel strand. One end of the steel strand located in the anchor hole is a compression anchoring end. The end of the cylindrical body close to the steel strand is a cylindrical section, and the end of the cylindrical body away from the steel strand is an external threaded section. The outer diameter of the locking nut is smaller than the outer diameter of the pressure relief seat, and the locking nut is threadedly engaged with the external threaded section.

8. The soft rock water-bearing tunnel surrounding rock repair device according to claim 6, characterized in that: The closed end of the constant resistance sleeve is provided with a through hole for the anchor rod to pass through. The outer wall of the closed end of the constant resistance sleeve is provided with an elastic sealing cup to prevent slurry from entering the inner cavity of the constant resistance sleeve. One end of the elastic sealing cup is sealed and fixedly connected to the outer wall of the closed end of the constant resistance sleeve, and the other end of the elastic sealing cup is sleeved on the outside of the anchor rod. The outer wall of the constant resistance sleeve is provided with a groove to increase the friction between the constant resistance sleeve and the solidified slurry.

9. The soft rock water-bearing tunnel surrounding rock repair device according to claim 6, characterized in that: A sealing gasket is provided between the tray and the wall of the tunnel, and the grouting pipe is sealed to the tray.

10. The soft rock water-bearing tunnel surrounding rock repair device according to claim 6, characterized in that: The hardness of the materials used to prepare the constant resistance sleeve and the pressure relief seat is higher than that of the materials used to prepare the pressure relief ring.

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