Targeted filling anti-slurry-leakage grouting anchor rod and construction method

Abstract

The invention belongs to the technical field of geotechnical engineering reinforcement, and discloses a targeted filling anti-slurry-leakage grouting anchor rod and a construction method.The targeted filling anti-slurry-leakage grouting anchor rod comprises a grouting anchor rod body, and the grouting anchor rod body is inserted into the anchor rod body; the periphery of the grouting anchor rod is fixedly connected with a first release structure and a second release structure, the first release structure is arranged close to the grouting end of the grouting anchor rod, and the second release structure is arranged on the side, away from the grouting end, of the first release structure. The first release structure is filled with a plurality of fiber chains, one end of each fiber chain is fixedly connected with the grouting anchor rod, the other end of each fiber chain is a movable end, and the fiber chains are connected with a plurality of blocking particles which expand when meeting water. The second release structure is also filled with a plurality of blocking particles, the first release structure and the second release structure both adopt water-soluble films, and the thickness of the first release structure is smaller than that of the second release structure. According to the method, the situation that the grouting pipeline is blocked due to early expansion of the blocking particles can be avoided, the blocking particles are effectively stopped in communicated fractures, and the stability and reliability of blocking are improved.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering reinforcement technology, specifically relating to a targeted filling anti-grouting anchor bolt and its construction method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Grouting anchors are generally used in geotechnical engineering reinforcement construction scenarios. The anchor is inserted into the borehole of the soil and rock mass, and reinforcement grout is injected into the anchor to fill and reinforce the borehole and surrounding cracks in the soil and rock mass.

[0004] Grouting anchors present the following technical challenges in fractured strata or highly permeable soil layers: While physical grout-stopping structures (such as orifice caps, rubber plugs, and quick-setting cement plugs) can seal the grouting orifice and prevent grout leakage, they cannot effectively fill fractures within the borehole that connect to the surrounding rock excavation face. In such cases, grout will flow out from these fractures, resulting in "grout leakage," a problem particularly severe in fractured rock masses, fractured strata, highly permeable strata, or fault zones. When leakage occurs, a large amount of grout is lost to the outside, preventing the grouting pressure from being increased and maintained, hindering the delivery of sufficient grout to the target grouting area, and preventing the filling and reinforcement of deep fractures.

[0005] To address the aforementioned technical problems, existing technology discloses a two-component grouting system, including a main grout supply pipeline and a sealing material supply pipeline. One end of the main grout supply pipeline is the main grout inlet, and the other end is the two-component grout outlet. The two-component grout outlet is connected to the grouting anchor. The sealing material expands upon contact with cement-based grout or pore water, forming a flexible and deformable filler in the borehole opening and rock fissures to seal the fissures.

[0006] The above solution has the following drawbacks: Although the above-mentioned scheme avoids premature expansion of the sealing material by controlling the distance of the mixing points, the sealing material is exposed to the grout immediately after mixing. If the grouting process is delayed or the flow rate changes, the sealing material may still absorb water and expand in the pipeline or anchor, causing the risk of blockage and affecting the continuity of grouting and construction safety. In addition, the sealing material is distributed with the flow of grout. After entering the crack, the sealing body formed by the expansion of the sealing material cannot be stopped under the pressure of subsequent grouting, resulting in poor crack sealing effect. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide a targeted filling anti-grout leakage grouting anchor bolt and construction method, which can solve the technical problems in the prior art where the sealing material enters the anchor bolt hole along with the grout, which poses a risk of clogging the anchor bolt or the sealing body in the crack is squeezed by the subsequent grouting pressure and cannot effectively seal the crack.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: In one aspect, a targeted filling anti-grouting anchor bolt is provided, including a grouting anchor bolt inserted into an anchor bolt hole; The outer periphery of the grouting anchor is fixedly connected to a first release structure and a second release structure. The first release structure is located near the grouting end of the grouting anchor, and the second release structure is located on the side of the first release structure away from the grouting end. The first release structure is filled with several fiber chains. One end of the fiber chain is fixedly connected to the grouting anchor, and the other end is a movable end. Several sealing particles are connected to the fiber chain. The sealing particles expand when they come into contact with water. The second release structure is also filled with several blocking particles. Both the first and second release structures use water-soluble membranes, and the thickness of the first release structure is less than that of the second release structure.

[0009] Preferably, the sealing particles expand under the immersion of the grouting fluid to form expanded particles, which seal the connecting cracks. The expanded particles combine with the grouting fluid to form the grouting body and the grouting anchor rod to form the anchor body.

[0010] Preferably, the fiber chain is spirally coiled inside the first release structure, and the sealing particles are fixedly connected to the fiber chain.

[0011] Preferably, the fiber chain is made of polyester or polypropylene fiber, which has the characteristics of being flexible in a wet state and alkali resistant, and is compatible with the cement-based alkaline grouting environment.

[0012] Preferably, the fiber chain is composed of fiber filaments, wherein the diameter of a single fiber filament is 300-500µm, the diameter of the fiber chain ranges from 0.3 to 1.5mm, and the length ranges from 500 to 900mm.

[0013] Preferably, two grout outlet holes are provided on the grouting anchor rod. The grout outlet holes are located on the side of the second release structure away from the grouting end, and the two grout outlet holes are staggered in the axial direction.

[0014] Preferably, a grout stop plug is fitted around the outer periphery of the grouting anchor bolt extending from the anchor bolt hole. The grout stop plug is made of conical rubber or polyurethane elastomer.

[0015] Preferably, the grout-stopping plug is located on the side away from the anchor bolt hole, and a washer and nut are fitted on the grouting anchor bolt; wherein the grouting anchor bolt extends out of the anchor bolt hole and has external threads, which are threaded to the nut; the diameter of the tail end of the grout-stopping plug and the outer diameter of the washer are both larger than the diameter of the anchor bolt hole.

[0016] Preferably, the grouting anchor is connected to the grouting pipe, and one end of the grouting pipe is threaded to the grouting joint. The outer diameter of the grouting pipe is the same as the outer diameter of the grouting anchor. After the grouting pipe and the grouting anchor are aligned, the grouting joint is threaded to the grouting pipe and the grouting anchor.

[0017] Secondly, a construction method for a targeted filling anti-grout leakage anchor bolt, as described above, is provided, with specific steps including: Drill and clean the anchor bolt holes, and install the grouting anchor bolts with the first and second release structures in the anchor bolt holes; fit the grout stop plug, gasket, and nut on the grouting anchor bolts, and connect the grouting pipes; Grouting fluid is injected into the grouting anchor. The grouting fluid first dissolves the first release structure to release the fiber chain. The fiber chain carries the sealing particles and flows into the connecting crack with the grouting fluid and stops. The sealing particles expand to form a preliminary physical barrier. As grout is continuously injected, the second release structure dissolves and releases a large number of sealing particles. These sealing particles expand and fill the connecting cracks as the grout continues to flow into them, forming a complete physical barrier.

[0018] Compared with the prior art, the advantages and positive effects of this invention are: This invention involves installing a first release structure and a second release structure on the outer periphery of a grouting anchor. The first release structure is filled with a fiber chain containing sealing particles, with one end of the fiber chain connected to the grouting anchor. The second release structure is filled with a large number of sealing particles. During grouting, the first release structure dissolves first. The fiber chain and sealing particles are carried by the grouting fluid and flow towards the connecting fractures, achieving a targeted response to the connecting fractures inside the anchor hole and sealing them. This solves the problem of grouting fluid escaping from the connecting fractures inside the anchor hole during grouting in complex geological conditions such as fractured rock layers and high water pressure formations. Simultaneously, the sealing particles, arranged on the outer periphery of the grouting anchor, prevent premature expansion and blockage of the grouting pipeline. Furthermore, the fiber chain effectively stops the sealing particles within the connecting fractures, working in conjunction with the sealing particles of the second release structure to seal the connecting fractures, improving the stability and reliability of the sealing and enhancing the functionality of the grouting anchor in complex geological environments. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1 This is a schematic diagram of the grouting anchor bolt in Embodiment 1 or Embodiment 2 of the present invention when it is not grouted; Figure 2 This is a schematic diagram of the dissolution of the first release structure during grouting of the grouting anchor bolt in Embodiment 1 or Embodiment 2 of the present invention; Figure 3 This is a schematic diagram showing the dissolution of the second release structure during grouting of the grouting anchor bolt in Embodiment 1 or Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the grouting anchor bolt when grouting is completed in Embodiment 1 or Embodiment 2 of the present invention; In the picture: 1. Grouting anchor; 2. Grouting channel; 3. Grouting pipe; 4. Grout outlet hole; 5. First release structure; 51. Fiber chain; 52. Sealing particles; 6. Second release structure; 7. Connecting fissure; 8. Grout stop plug; 9. Gasket; 10. Nut; 11. Grouting joint; 12. Anchoring agent; 13. Surrounding rock; 14. Anchor bolt hole; 15. Expansion particles. Detailed Implementation

[0021] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, 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.

[0022] The present invention will now be described in detail with reference to the accompanying drawings.

[0023] Example 1 This embodiment discloses a targeted filling anti-grout leakage grouting anchor bolt, such as... Figure 1 As shown, it includes a grouting anchor rod 1, which is inserted into an anchor hole 14 pre-drilled in the surrounding rock 13. The grouting anchor rod 1 has a hollow structure, and the inside of the grouting anchor rod 1 is a grouting channel 2. One end of the grouting anchor rod 1 is the grouting end, and the other end is the sealing end. The grouting end is used to connect to external grouting equipment. The grouting liquid flows in from the grouting end of the grouting anchor rod 1, flows out from the grout outlet after passing through the grouting channel 2, and fills the anchor hole 14.

[0024] Understandably, after the grouting fluid flows out of the grout outlet hole on the grouting anchor rod 1 and fills the anchor rod hole 14, it penetrates into the surrounding rock 13 under pressure to reinforce it.

[0025] In practical applications, the surrounding rock 13 around the anchor bolt hole 14 has a connecting fissure 7 that communicates with the excavation face. When the grouting fluid flows from the grouting anchor 1 into the anchor bolt hole 14, the grouting fluid flows out from the connecting fissure 7, which will cause grout leakage and waste of grouting fluid. At the same time, the pressure in the anchor bolt hole 14 will never rise, and the grouting fluid will not be able to be squeezed and penetrate into the surrounding rock 13.

[0026] In this embodiment, a graded release structure is fixedly connected to the outer periphery of the grouting anchor 1. The graded release structure includes a first release structure 5 and a second release structure 6, wherein the first release structure 5 is disposed near the grouting end, and the second release structure 6 is disposed on the side of the first release structure 5 away from the grouting end. Figure 1 As shown, the first release structure 5 is filled with several fiber chains 51. One end of each fiber chain 51 is fixedly connected to the outer wall of the grouting anchor 1, and the other end is a movable end. Several sealing particles 52 are connected to the fiber chains 51. The second release structure 6 is also filled with several sealing particles 52. In this embodiment, both the first release structure 5 and the second release structure 6 are water-soluble membranes, and the thickness of the first release structure is less than the thickness of the second release structure.

[0027] It should be noted that the sealing particles 52 have the property of expanding upon contact with water.

[0028] It should be noted that the staged release structure refers to a component that releases the sealing material in stages during the grouting process. In this embodiment, the first release structure and the second release structure are made by using a water-soluble film, and the thickness of the first release structure is smaller than that of the second release structure. This achieves the effect that during the grouting process, as the grouting fluid washes over the material, the first release structure dissolves and releases first, and the second release structure dissolves and releases later.

[0029] In this embodiment, water-soluble films of different thicknesses can be used to make the thickness of the first release structure smaller than that of the second release structure. The water-soluble film can be a polyvinyl alcohol water-soluble film or a starch-based water-soluble film, and the dissolution time can be controlled by adjusting the film thickness.

[0030] In some implementations, the dissolution time can be changed by altering the material composition. For example, changing the alcohol content in the polyvinyl alcohol aqueous film can change the dissolution time of the polyvinyl alcohol aqueous film.

[0031] In this embodiment, as Figure 2 As shown, the first release structure 5 dissolves first, releasing the fiber chain 51. The grout flows toward the connecting fissure 7, carrying the movable end of the fiber chain 51 to flow toward the connecting fissure 7 as well. The movable end of the fiber chain 51 enters from the entrance of the connecting fissure 7. During this process, the sealing particles 52 on the fiber chain 51 expand under the soaking of the grout to form expanded particles 15, which initially seal the entrance of the connecting fissure 7.

[0032] It is understandable that, such as Figure 3As shown, the second release structure 6 dissolves after a set time interval (e.g., the thickness of the second release structure is twice the thickness of the first release structure), releasing more sealing particles 52 inside. These particles continue to flow towards the connecting crack 7 under the influence of the grouting fluid. Similarly, the sealing particles 52 expand under the immersion of the grouting fluid to form expanded particles 15, which re-seal the entrance to the connecting crack 7, forming a complete physical barrier and thus achieving a complete filling effect.

[0033] like Figure 4 As shown, after grouting is completed, the expanding particles 15 combine with the grouting fluid to form the grouting body and the grouting anchor rod to form the anchor body.

[0034] It is also understandable that the fiber chain 51 and the sealing particles 52, carried by the grouting fluid, flow towards the connecting fissure 7, enabling a targeted response to the connecting fissure 7 inside the anchor bolt hole 14. One end of the fiber chain 51 is fixed, allowing the movable end to enter the connecting fissure 7 without being washed away. The sealing particles 52 on the fiber chain 51 expand, forming a preliminary seal at the entrance of the connecting fissure 7, thereby intercepting subsequent sealing particles 52. This allows the remaining sealing particles 52 to continue expanding and bonding at the entrance of the connecting fissure 7, ultimately sealing the connecting fissure 7.

[0035] In this embodiment, the water-soluble membranes of the first release structure 5 and the second release structure 6 are polyvinyl alcohol water-soluble membranes, wherein the thickness of the water-soluble membrane of the first release structure 5 is 1.5 mm and the thickness of the water-soluble membrane of the second release structure 6 is 3 mm.

[0036] It is understandable that the staged release of the first release structure 5 and the second release structure 6, combined with the water-swelling properties of the sealing particles 52 and their tendency to flow with the grouting fluid towards the connecting fractures 7, can target and seal the connecting fractures 7, solving the problem of grouting fluid escaping from the connecting fractures 7 inside the anchor bolt hole during grouting under complex geological conditions such as fractured rock layers and high water pressure strata. Simultaneously, in this embodiment, the sealing particles 52 are arranged on the outer periphery of the grouting anchor bolt 1 to prevent premature expansion of the sealing particles 52 that could cause blockage of the grouting pipeline. Furthermore, the fiber chain 51 effectively stops the sealing particles 52 within the connecting fractures 7, improving the stability and reliability of the sealing and enhancing the functionality of the grouting anchor bolt 1 in complex geological environments.

[0037] like Figure 1 As shown, in this embodiment, the fiber chain 51 is spirally coiled inside the first release structure 5. This structural design is to ensure that the fiber chain 51 is sufficiently long after release, such as... Figure 2 As shown, the fiber chain 51 can flow with the grout to the entrance of the connecting fissure 7, ensuring that the fiber chain 51 can extend into the connecting fissure 7 and preventing the sealing range from being limited due to insufficient length.

[0038] It should be noted that after the grouting fluid washes and dissolves the first release structure 5, the grouting fluid will generate drag force (viscous resistance) and pressure on the fiber chain 51. Since the fiber chain 51 is initially spirally coiled, the scouring force of the grouting fluid will cause the fiber chain 51 to gradually unfold and elongate. The movable end of the fiber chain 51 can respond to the flow direction of the grouting fluid and flow towards the entrance of the connecting fissure 7. At the same time, the sealing particles 52 on the fiber chain 51 expand upon encountering the grouting fluid, forming expanded particles 15. With the other end of the fiber chain 51 fixedly connected to the grouting anchor 1, the expanded sealing particles 52 remain stationary at the entrance of the connecting fissure 7, achieving initial sealing.

[0039] In this embodiment, the fiber chain 51 is made of polyester or polypropylene fiber, which has the characteristics of being flexible in wet conditions and alkali resistant. It is compatible with the cement-based alkaline grouting environment, has strong chemical stability, and avoids breakage or strength loss caused by the increase of environmental pH value. At the same time, it also avoids the fiber chain 51 from being insufficiently flexible and having reduced strength in the cement-based alkaline grouting environment, which would prevent it from reliably carrying the sealing particles 52 with the grouting fluid to the inlet of the connecting crack 7.

[0040] Understandably, the achievement of wet flexibility depends on hydrophilic modification, which allows the fiber chain 51 to naturally stretch out without becoming stiff after being soaked in the grouting liquid, making it easy to dynamically adjust its shape according to the flow direction of the grouting liquid.

[0041] In this embodiment, the fiber chain 51 is composed of fiber filaments, wherein the diameter of a single fiber filament is 300–500 µm, the diameter of the fiber chain 51 ranges from 0.3–1.5 mm, and the length ranges from 500–900 mm. By setting the diameter range of the fiber chain 51, it is ensured that the fiber chain 51 has both flexibility and tensile strength under the impact of the grouting fluid, avoiding breakage caused by an excessively small diameter, and avoiding increased rigidity of the fiber chain 51 due to an excessively large diameter, which would prevent it from flowing with the grouting fluid into the entrance of the connecting fissure 7. The length range of the fiber chain 51 is set to adapt to the size distribution of the entrance of the connecting fissure 7, avoiding the fiber chain 51 being too short to enter the entrance of the connecting fissure 7, and avoiding the fiber chain 51 being too long to cause entanglement and blockage, which would also prevent it from entering the entrance of the connecting fissure 7.

[0042] In this embodiment, the sealing particles 52 are fixedly connected to the fiber chain 51 by adhesive bonding, ensuring that the sealing particles 52 remain fixed when the grout flows and washes away, preventing them from being washed away and falling off, thus preventing them from being unable to seal the entrance of the connecting crack 7.

[0043] In this embodiment, the fiber chain 51 is made of polyester fiber and is spirally wound inside the first release structure 5 of the grouting anchor bolt; a number of sealing particles 52 are connected to the fiber chain 51 by adhesive bonding. When grouting begins, the water-soluble film of the first release structure 5 dissolves, the fiber chain 51 is released and extends and flows with the grouting fluid, and enters the entrance of the connecting fissure 7. The sealing particles 52 at the entrance of the connecting fissure 7 expand and achieve targeted sealing at the entrance of the connecting fissure 7.

[0044] like Figures 1 to 4 As shown, in this embodiment, two grout outlet holes 4 are opened on the side of the graded release structure away from the grouting end for the grouting fluid to flow out. The grout outlet holes 4 are staggered in the axial direction of the side wall of the grouting anchor rod 1 to reduce the single-point impact pressure and avoid the concentrated arrangement or single-direction design of the grout outlet holes, which would cause the grouting fluid to generate local high pressure impact on the outer wall of the anchor rod. At the same time, it can also release the grouting fluid from different heights and directions to prevent the grout from continuously impacting a single area and forming a uniform pressure field.

[0045] In this embodiment, the diameter of the grout outlet 4 is 6 mm, which can be formed by drilling, stamping, or casting. This size balances the grouting flow rate and fluid dynamics characteristics, avoiding the problems of easy clogging with small orifices and high impact with large orifices. It is suitable for complex scenarios such as fractured rock formations and high water pressure formations, improving construction efficiency.

[0046] like Figures 1 to 4 As shown, in this embodiment, the grouting end of the grouting anchor rod 1 extends out of the opening of the anchor rod hole 14. A grout stop plug 8 is sleeved on the outer periphery of the grouting anchor rod 1 extending out of the anchor rod hole 14. The grout stop plug 8 is located on the side of the first release structure 5 away from the second release structure 6, and the grout stop plug 8 is located at the junction of the grouting anchor rod 1 and the opening of the anchor rod hole 14. It is used to seal the anchor rod hole 14, so that the inside of the anchor rod hole 14 is sealed, forcing the grouting liquid to penetrate into the surrounding rock 13 inside the anchor rod hole 14.

[0047] In this embodiment, the grout stopper 8 is made of conical rubber or polyurethane elastomer, which uses elastic restoring force to fit tightly against the hole wall of the anchor bolt hole 14 to achieve a one-way sealing function and ensure that the anchor bolt hole 14 is closed.

[0048] In practical applications, the grout stop plug 8 may shift or loosen under grouting pressure due to the lack of a reliable clamping and fixing mechanism, resulting in poor sealing of the anchor bolt hole 14. This causes the grout to overflow from the anchor bolt hole 14, affecting the establishment and maintenance of grouting pressure, and thus reducing the reinforcement effect and construction efficiency.

[0049] In this embodiment, the distance between the first release structure 5 and the grout stopper 8 is 110-500 mm, and the distance between the second release structure 6 and the grout stopper 8 is 650-900 mm, ensuring that the sealing particles 52 have sufficient deployment distance and spatial distribution capability in the flow path to adapt to the scale inhomogeneity of the connecting cracks or pore structures.

[0050] like Figures 1 to 4 As shown, on the side of the grout-stopping plug 8 away from the anchor bolt hole 14, a washer 9 and a nut 10 are also fitted onto the grouting anchor bolt 1; wherein, an external thread is formed on the outer periphery of the grouting anchor bolt 1 extending out of the anchor bolt hole 14, and the nut 10 is threadedly connected to the grouting anchor bolt 1. It can be understood that by tightening the nut 10, the washer 9 is pressed, so that the washer 9 applies pressure toward the grout-stopping plug 8 to seal the opening of the anchor bolt hole 14.

[0051] It is also understandable that the diameter of the tail end of the grout stop plug 8 and the outer diameter of the gasket 9 are both larger than the diameter of the anchor bolt hole 14. When the nut 10 is tightened, the gasket 9 can evenly distribute the load and prevent the grout stop plug 8 from deforming or breaking due to local stress concentration. At the same time, it ensures that the grout stop plug 8 is firmly sealed at the opening of the anchor bolt hole 14, effectively blocking the grout backflow path.

[0052] like Figures 1 to 4 As shown, the grouting end of the grouting anchor rod 1 is connected to the grouting pipe 3. One end of the grouting pipe 3 is threaded to the grouting connector 11. The outer diameter of the grouting pipe 3 is the same as the outer diameter of the grouting anchor rod 1. The grouting pipe 3 is aligned with the axis of the grouting anchor rod 1. The grouting connector 11 is moved toward the grouting anchor rod 1. The grouting pipe 3 and the grouting anchor rod 1 are connected as one unit. The other end of the grouting pipe 3 is connected to the grouting equipment (such as a grouting pump).

[0053] Understandably, the grouting joint 11 is made of high-strength and corrosion-resistant alloy steel or nylon-reinforced composite material, possessing good impact resistance and wear resistance. The grouting end of the grouting anchor 1 is connected and sealed to the grouting pipe 3 through the grouting joint 11 to prevent the grouting fluid from leaking from the connection under grouting pressure, thus avoiding material waste, making it difficult to establish and maintain stable grouting pressure, and affecting the overall reinforcement effect and construction efficiency.

[0054] like Figures 1 to 4 As shown, the other end of the grouting anchor rod 1 is the sealing end, and the outer periphery of the sealing end is coated with anchoring agent 12 for connection with the anchor rod hole 14. The anchoring agent 12 can be epoxy resin-based or cement-based anchoring agent, the purpose of which is to enhance the interfacial bonding force between the sealing end of the grouting anchor rod 1 and the surrounding rock 13 through chemical bonding.

[0055] In this embodiment, the grouting fluid uses cement-based grouting material, and the sealing particles 52 include modified bentonite, superabsorbent polymer (SAP), mineral micropowder and cellulose composite material, and quartz sand inert aggregate. Modified bentonite, as the main expanding substrate, possesses natural expansibility and good interfacial compatibility; the superabsorbent polymer (SAP) can improve the reaction rate and expansion ratio; the mineral micropowder and cellulose composite material can enhance adhesion and anti-dispersion properties, and after expansion, it can form a three-dimensional support structure, improving the overall sealing strength. The quartz sand inert aggregate provides skeletal support for the sealing particles, enhancing the material's shear, compressive, and rheological resistance.

[0056] In this embodiment, the sealing particles 52 have a particle size range of 0.3 mm to 2.5 mm. The sealing particles 52 contain 10% to 30% by mass of quartz sand particles with a particle size of 0.1 mm to 1.0 mm, forming an inter-particle support framework. After contact with the grouting fluid, the sealing particles 52 expand within 30 to 90 seconds, with a volume expansion ratio of 500% to 1000% of the original volume. After expansion, they form a flexible, structurally stable, and insoluble filler that can seal the connecting cracks 7. The sealing particles 52 can exist stably in an alkaline grouting environment with a pH of 10 to 12 without degradation, and possess resistance to water seepage, shearing, and chemical erosion.

[0057] Example 2 This embodiment discloses a construction method for a targeted filling anti-grout leakage grouting anchor bolt, which applies a targeted filling anti-grout leakage grouting anchor bolt disclosed in Embodiment 1. The specific steps include: Drill anchor bolt holes 14 and clean the holes. Install the grouting anchor bolt 1 with the staged release structure in the anchor bolt holes 14. A grout stop plug 8, a gasket 9, and a nut 10 are fitted onto the grouting end of the grouting anchor rod 1 to ensure axial positioning and end sealing of the grouting anchor rod 1, and a grouting pipe 3 is connected to the grouting end. Grouting fluid is injected into the grouting anchor through the grouting pipe 3. The grouting fluid first dissolves the water-soluble film of the first release structure 5 to release the fiber chain 51. The fiber chain 51 carries the sealing particles 52, which flow into the connecting crack 7 with the grouting fluid and stop there. The sealing particles 52 expand to form a preliminary physical barrier. As the grouting fluid is continuously injected, the water-soluble film of the second release structure 6 dissolves, a large number of sealing particles 52 are released, and as the grouting fluid continues to flow into the connecting crack 7, they further expand and fill, forming a complete physical barrier; after sealing the connecting crack 7, the pressure in the anchor bolt hole 14 rises and tends to stabilize, the grouting fluid fills the unsaturated area, and the sealing particles 52 and the grouting fluid harden together to form an integral anchor body.

[0058] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A run-off-preventing grouting anchor rod of targeted filling, characterized in that, The grouting anchor rod is inserted in the anchor rod; The outer periphery of the grouting anchor rod is fixedly connected with a first release structure and a second release structure, the first release structure is arranged close to the grouting end of the grouting anchor rod, and the second release structure is arranged on the side of the first release structure away from the grouting end; The first release structure is filled with a plurality of fiber chains, one end of the fiber chain is fixedly connected with the grouting anchor rod, the other end is a movable end, a plurality of blocking particles are connected on the fiber chain, and the blocking particles swell when meeting water; The second release structure is also filled with a plurality of blocking particles, the first release structure and the second release structure are both made of water-soluble film, and the thickness of the first release structure is less than that of the second release structure.

2. A target filled anti-run slurry anchor according to claim 1, wherein, The blocking particles swell to form swelling particles under the soaking of the grouting liquid, the swelling particles block the connected fissures, the swelling particles and the grouting body formed by the grouting liquid and the grouting anchor rod are combined to form an anchoring body.

3. A target filled anti-run slurry anchor according to claim 1, wherein, The fiber chain is spirally coiled in the inside of the first release structure, and the blocking particles are fixedly connected with the fiber chain.

4. A target filled anti-run slurry anchor according to claim 1, wherein, The fiber chain is made of polyester or polypropylene fiber, has the characteristics of flexibility in a wet state and alkali resistance, and is compatible with the cement-based alkali grouting environment.

5. A target filled anti-run slurry anchor according to claim 1, wherein, The fiber chain is composed of fiber filaments, wherein the diameter of a single fiber filament is 300-500 µm, the diameter of the fiber chain ranges from 0.3 to 1.5 mm, and the length of the fiber chain ranges from 500 to 900 mm.

6. A target filled anti-run slurry anchor according to claim 1, wherein, Two grouting holes are arranged on the grouting anchor rod, the grouting holes are arranged on the side of the second release structure away from the grouting end, and the two grouting holes are staggered in the axial direction.

7. A target filled anti-run slurry anchor according to claim 1, wherein, A stopper is arranged on the outer periphery of the grouting anchor rod extending out of the anchor hole, and the stopper is made of a conical rubber or a polyurethane elastomer.

8. A target filled anti-run slurry anchor according to claim 7, wherein, A gasket and a nut are arranged on the grouting anchor rod away from the anchor hole, the outer periphery of the grouting anchor rod extending out of the anchor hole is provided with external threads, and the external threads are threadedly connected with the nut; the diameter of the tail end of the stopper and the outer diameter of the gasket are both greater than the diameter of the anchor hole.

9. A target filled anti-run slurry anchor according to claim 1, wherein, The grouting anchor rod is connected with a grouting pipe, one end of the grouting pipe is threadedly connected with a grouting connector, the outer diameter of the grouting pipe is consistent with the outer diameter of the grouting anchor rod, the grouting connector is threadedly connected with the grouting pipe and the grouting anchor rod after the grouting pipe and the grouting anchor rod are aligned in the axial direction.

10. A method of construction of a target-filled anti-run grouting anchor rod according to any one of claims 1-9, characterized in that, The specific steps include: The anchor hole is drilled and cleaned, the grouting anchor rod provided with the first release structure and the second release structure is installed in the anchor hole, and the stopper, the gasket, the nut, and the grouting pipe are arranged on the grouting anchor rod; The grouting liquid is injected into the grouting anchor rod, the grouting liquid first dissolves the first release structure to release the fiber chain, the fiber chain carries the blocking particles, and the blocking particles flow into the connected fissures with the grouting liquid and stagnate, and the blocking particles swell to form a preliminary physical barrier; The grouting liquid is continuously injected, the second release structure dissolves to release a large number of blocking particles, the blocking particles continue to flow into the connected fissures with the grouting liquid and further swell and fill to form a complete physical barrier.

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