Anti-slurry running grouting anchor rod and construction method thereof

Abstract

This invention belongs to the field of geotechnical engineering reinforcement technology, and discloses a grouting anchor rod and its construction method for preventing grout leakage. The invention includes a grouting anchor rod inserted into an anchor rod hole, with a grout outlet hole at the top; a rubber sleeve fixedly connected to the tail end of the grouting anchor rod, located between the grout outlet hole and the connecting fissure within the anchor rod hole; several T-shaped pressure tongue springs uniformly connected circumferentially to the grouting anchor rod inside the rubber sleeve, each T-shaped pressure tongue spring including a horizontal spring, a vertical spring fixedly connected to the center of the horizontal spring, and the tail end of the vertical spring fixedly connected to the outer wall of the grouting anchor rod and covered by the rubber sleeve; the horizontal springs of adjacent T-shaped pressure tongue springs are pressed together in a clockwise or counterclockwise circular shape, compressing the horizontal springs towards the grouting anchor rod; the pressed horizontal springs are bonded together by a water-soluble film; the elasticity of the T-shaped pressure tongue springs is greater than the shrinkage performance of the rubber sleeve. This invention can prevent the anchor rod hole opening from being crushed due to excessive pressure, and the connecting fissure provides reinforcement.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering reinforcement technology, specifically relating to a grouting anchor rod and construction method for preventing grout leakage. 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 widely used in geotechnical engineering reinforcement construction. During construction, the grouting anchor is inserted into the anchor hole of the rock mass, and then reinforcement grout is injected into the anchor to reinforce the anchor hole and surrounding cracks.

[0004] Grouting anchors present the following technical problems in fractured strata or highly permeable soil layers: When drilling anchor holes in rock masses, due to the inherent characteristics of the rock mass or drilling vibrations, interconnected fractures may appear near the anchor hole opening. During subsequent grouting construction, even if a grouting plug is installed at the tail end of the grouting anchor to seal it, grout will still flow into the interconnected fractures, causing grout leakage. This results in insufficient grouting pressure in the anchor hole, and the pressure input by the grouting pump cannot be effectively transmitted to the grouting area, making it difficult to establish and maintain the grouting pressure at the design value for a long period of time. Consequently, it affects the diffusion of grout into the deeper parts of the surrounding rock and fails to effectively fill the internal fractures of the anchor hole.

[0005] The prior art discloses a self-drilling grouting anchor bolt with grout stop plug suitable for soft rock formations, including a hollow grouting anchor bolt body and an expansion rubber grout stop pipe installed at the tail of the grouting anchor bolt body. The grouting anchor bolt body works with a drill bit to drill the anchor bolt into the rock formation, and then the expansion rubber grout stop pipe expands to plug the borehole and ensure grouting pressure.

[0006] The above method involves installing an expansion rubber grout stop pipe at the tail of the grouting anchor bolt, first using the expansion rubber grout stop pipe to plug the borehole before grouting. This method has the following drawbacks: The expansion rubber grout-stopping pipe in the above scheme expands before grouting and continues to expand during the grouting process. This may crush the opening of the anchor bolt hole, causing the opening of the anchor bolt hole to enlarge and making it impossible to seal the opening of the anchor bolt hole, thus turning it into a "waste hole". Furthermore, in the above scheme, the opening is sealed and grouting is performed after the expansion rubber grout-stopping pipe expands, without grouting and reinforcing the cracks at the opening. During the continuous pressurized grouting process, the opening may also break. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide a grouting anchor rod and construction method for preventing grout leakage, which can solve the technical problem in the prior art where installing an expansion rubber grout stop tube at the tail of the grouting anchor rod causes the expansion rubber grout stop tube to expand before grouting, resulting in the anchor rod hole opening breaking and ineffective grouting.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: Firstly, a grouting anchor bolt for preventing grout leakage is provided, comprising: Grouting anchors are inserted into anchor holes, and grout outlet holes are opened at the top of the grouting anchors. The rubber sleeve is fixedly connected to the grouting anchor rod at its tail end. The rubber sleeve is located between the grout outlet hole and the connecting fissure inside the anchor rod hole. T-shaped depressor springs, several T-shaped depressor springs are evenly connected to the grouting anchor rod along the circumference inside the rubber sleeve. The T-shaped depressor spring includes a horizontal spring, a vertical spring is fixedly connected to the center of the horizontal spring, and the tail end of the vertical spring is fixedly connected to the outer wall of the grouting anchor rod and is covered by the rubber sleeve. The horizontal spring pieces of adjacent T-shaped depressor spring pieces are pressed together in a clockwise or counterclockwise manner to form a ring, so that the vertical spring pieces are in a compressed state facing the grouting anchor; the horizontal spring pieces pressed together are covered and bonded by a water-soluble film. The elasticity of the T-shaped tongue depressor is greater than the shrinkage performance of the rubber sleeve.

[0009] Preferably, a grout stop plug is fitted onto the grouting anchor at the anchor hole opening, and the top of the grout stop plug covers the bottom outside of the rubber sleeve.

[0010] Preferably, the grout stopper is made of frustoconical rubber or polyurethane elastomer.

[0011] Preferably, the grouting anchor rod has an external thread extending from the outer periphery of the anchor rod hole, and a washer and nut are fitted on the grouting anchor rod. The nut is connected to the external thread on the outer periphery of the grouting anchor rod, and the outer diameter of the washer is larger than the diameter of the grout stop plug.

[0012] Preferably, the length of the rubber sleeve is 400-500mm, and the bottom quarter section of the rubber sleeve is bonded and fixed to the grouting anchor rod; the connection point between the T-shaped pressure tongue spring and the grouting anchor rod is located above the connection point between the rubber sleeve and the grouting anchor rod.

[0013] Preferably, the tail end of the grouting anchor is connected to a grouting pipe, one end of the grouting pipe is connected to a grouting joint via an external thread, the outer diameter of the grouting pipe is the same as the outer diameter of the grouting anchor, the grouting joint is threadedly connected to the grouting pipe and the grouting anchor, and the other end of the grouting pipe is connected to grouting equipment.

[0014] Preferably, an anchoring agent is applied to the outer periphery of the end of the grouting anchor rod away from the grouting pipe.

[0015] Preferably, multiple grout outlets are opened on the side of the rubber sleeve away from the anchor bolt hole, and each channel includes multiple grout outlets evenly arranged along the circumference of the grouting anchor bolt.

[0016] Secondly, a construction method for the aforementioned grouting anchor bolt to prevent grout leakage is provided, the specific steps of which include: T-shaped pressure tongue springs are fixedly connected to the grouting anchor rod. The horizontal springs of the T-shaped pressure tongue springs are pressed into a ring shape and covered and adhered by a water-soluble film. Then, a rubber sleeve is fitted on the outside of the T-shaped pressure tongue springs, and the bottom of the rubber sleeve is fixedly connected to the grouting anchor rod. Then, a grout stop plug is fitted on the outside of the bottom of the rubber sleeve. Drill and clean the anchor bolt holes. Place the grouting anchor bolt, equipped with a T-shaped pressure tongue spring, rubber sleeve, and grout stop plug, into the anchor bolt hole. Install the gasket and nut on the grouting anchor bolt, then connect the grouting pipe and inject grout into the grouting anchor bolt.

[0017] Preferably, during grouting, after the grouting pressure rises and stabilizes at the set pressure, the pressure is slowly increased to the set permeation pressure to allow the grout to permeate into the rock mass around the anchor bolt hole. When the pressure stabilizes at the set permeation pressure and the flow rate stabilizes at the set flow rate for a set time, the grouting is stopped.

[0018] Compared with the prior art, the advantages and positive effects of this invention are: This invention connects a rubber sleeve to a grouting anchor rod. The rubber sleeve is located between the grout outlet and the connecting fissure of the anchor rod hole. Inside the rubber sleeve, several T-shaped pressure tongue springs are evenly connected to the grouting anchor rod. The horizontal springs of the T-shaped pressure tongue springs are pressed into a ring shape and covered and adhered by a water-soluble film, so that the vertical springs of the T-shaped pressure tongue springs are in a compressed state facing the grouting anchor rod, and the elasticity of the T-shaped pressure tongue springs is greater than the shrinkage performance of the rubber sleeve. During grouting, when the grout flows through the rubber sleeve and into the connecting fissure, it wets the horizontal springs inside the rubber sleeve, causing the water-soluble film to dissolve. At the same time, the horizontal springs spring open, and the vertical springs push the rubber sleeve outward and against the inner wall of the anchor rod hole, preventing the grout from continuing to flow into the connecting fissure. The sealing process of this invention is triggered naturally by the flow of grout, which opens the rubber sleeve using a T-shaped pressure tongue spring. This effectively prevents grout leakage and avoids the rubber sleeve directly pressing on the opening of the anchor bolt hole, thus preventing the hole from being crushed due to excessive pressure. Furthermore, after the rubber sleeve blocks the channel through which the grout flows to the connecting fracture, a portion of the grout can remain within the connecting fracture and eventually solidify, reinforcing the fracture and improving the reliability of geotechnical engineering reinforcement. 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 an axial cross-sectional view of a grouting anchor bolt for preventing grout leakage in Embodiment 1 or Embodiment 2 of the present invention when it is not grouted; Figure 2 This is from Embodiment 1 or Embodiment 2 of the present invention. Figure 1 Cross-sectional view of AA; Figure 3This is an axial cross-sectional view of a grouting anchor bolt for preventing grout leakage according to Embodiment 1 or Embodiment 2 of the present invention, taken immediately after grouting. Figure 4 This is from Embodiment 1 or Embodiment 2 of the present invention. Figure 3 Cross-sectional view of BB; Figure 5 This is an axial cross-sectional view of a grouting anchor rod for preventing grout leakage according to Embodiment 1 or Embodiment 2 of the present invention when grouting is completed; Figure 6 This is a three-dimensional view of the slurry stop plug of Embodiment 1 or Embodiment 2 of the present invention; In the picture: 1. Grouting anchor; 11. Grout outlet hole; 12. Anchoring agent; 2. Anchor hole; 21. Connecting fissure; 3. Rubber sleeve; 4. T-shaped pressure tongue spring; 41. Horizontal spring; 42. Vertical spring; 43. Water-soluble film; 5. Grout stop plug; 6. Gasket; 7. Nut; 8. Grouting pipe; 9. Grouting joint. 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 grouting anchor bolt for preventing grout leakage, such as... Figure 1 , Figure 3 , Figure 5 As shown, the system includes a grouting anchor rod 1, which is inserted into an anchor hole 2 drilled in the rock mass; a rubber sleeve 3 is connected to the grouting anchor rod 1, and the tail end of the rubber sleeve 3 (facing the opening of the anchor hole 2) is fixedly connected to the grouting anchor rod 1; along the circumference of the grouting anchor rod 1, several T-shaped pressure tongue springs 4 are evenly connected to the grouting anchor rod 1 inside the rubber sleeve 3. Figure 2 , Figure 4 As shown, the T-shaped tongue depressor 4 includes a horizontal spring 41, with a vertical spring 42 fixedly connected to the center of the horizontal spring 41, as shown. Figure 1 As shown, the other end of the vertical spring piece 42 is fixedly connected to the outer wall of the grouting anchor rod 1 and is covered by the rubber sleeve 3.

[0024] In this embodiment, the T-shaped tongue depressor 4 is made of a metal spring sheet, and the horizontal spring sheet 41 and the vertical spring sheet 42 are integrally manufactured.

[0025] like Figure 2 , Figure 4As shown, the horizontal spring pieces 41 of adjacent T-shaped depressor spring pieces 4 are pressed together in a clockwise or counterclockwise manner to form a ring, so that the vertical spring pieces 42 of the T-shaped depressor spring pieces are in a compressed state towards the grouting anchor rod 1. In this embodiment, the horizontal spring pieces 41 of the T-shaped depressor spring pieces 4 facing clockwise are pressed onto the horizontal spring pieces 41 of the next T-shaped depressor spring pieces 4 facing counterclockwise. In this embodiment, the horizontal spring pieces 41 pressed together are covered and bonded by a water-soluble film 43, and the rubber sleeve 3 covers the outside of the ring-shaped horizontal spring pieces 41. It can be understood that under the constraint of the water-soluble film 43, the horizontal spring pieces 41 of the T-shaped depressor spring pieces 4 cannot pop out in a direction away from the grouting anchor rod 1, so that the vertical spring pieces 42 of the T-shaped depressor spring pieces 4 are always in a compressed state.

[0026] In this embodiment, there are eight T-shaped depressor springs 4, evenly arranged around the circumference of the grouting anchor 1, with the transverse springs 41 of the eight T-shaped depressor springs 4 forming a circle. In this embodiment, the rubber sleeve 3 is made of an elastic material, such as natural rubber or nitrile rubber, and is formed by a vulcanization process. The water-soluble film is a thin film material that dissolves in water and is used to temporarily fix the transverse springs 41, ensuring that the T-shaped depressor springs 4 dissolve and release in time when in contact with the grout to open the rubber sleeve 3.

[0027] It should be noted that the elasticity of the T-shaped depressor spring 4 is greater than the shrinkage performance of the rubber sleeve 3, such as... Figure 4 As shown, when the horizontal spring 41 is unrestrained, the vertical spring 42 pops out in a direction away from the grouting anchor 1, which will cause the top of the rubber sleeve 3 to open in a direction away from the grouting anchor 1, thereby opening the top of the rubber sleeve 3 and pressing it against the inner wall of the anchor hole 2.

[0028] like Figure 1 , Figure 3 , Figure 5 As shown, a grout outlet hole 11 is opened at the top of the grouting anchor bolt 1 for grouting into the anchor bolt hole 2. A rubber sleeve 3 is located between the grout outlet hole 11 and the connecting fissure 21, that is, the rubber sleeve 3 is positioned on the side of the connecting fissure 21 at the opening of the anchor bolt hole 2 facing the grout outlet hole 11. It can be understood that, as... Figure 3 As shown, when the grout flows to the connecting crack 21 at the opening of the anchor bolt hole 2, the grout flows through the rubber sleeve 3 and wets the horizontal elastic pieces 41 inside the rubber sleeve 3. This causes the water-soluble film 43 between the horizontal elastic pieces 41 to dissolve. Then, as the horizontal elastic pieces 41 spring open, the vertical elastic pieces 42 also lose their restraint, pushing against the top of the rubber sleeve 3 outwards and against the inner wall of the anchor bolt hole 2. Figure 5 As shown, when the grout continues to flow towards the opening of the anchor bolt hole 2, it will enter the inside of the rubber sleeve 3, and together with the T-shaped pressure tongue spring 4, it will hold the rubber sleeve 3 together (as shown). Figure 5As shown, the rubber sleeve 3 is completely attached to the hole wall of the anchor bolt hole 2 and continues to be spread out. Because the bottom end of the rubber sleeve 3 is fixedly connected to the grouting anchor bolt 1, the grout continues to flow into the connecting crack 21.

[0029] It should be noted that the rubber sleeve 3 is located between the grout outlet 11 and the connecting fissure 21. During this process, the rubber sleeve 3, in conjunction with the T-shaped pressure tongue spring 4, can block the channel of grout flowing to the connecting fissure 21, effectively preventing grout leakage. Furthermore, the sealing process in this embodiment is naturally triggered by the flow of grout, and the rubber sleeve 3 does not directly compress the opening of the anchor bolt hole 2. Compared to the grout-stopping device in the prior art that expands in advance and continuously squeezes the opening, this embodiment can avoid the anchor bolt hole 2 opening being crushed due to excessive pressure. In addition, the grout can also flow through the connecting fissure 21. After the rubber sleeve 3 blocks the channel of grout flowing to the connecting fissure 21, the grout can stay in the connecting fissure 21 and eventually solidify, thus reinforcing the connecting fissure 21.

[0030] In practical applications, the bottom of the rubber sleeve 3 is only fixedly connected to the grouting anchor 1 (e.g., bonded). Under grouting pressure, the rubber sleeve 3 may shift towards the opening of the anchor hole 2, causing the opening to bear concentrated stress and break, resulting in grouting failure and the formation of a waste hole. Therefore, as... Figure 1 , Figure 3 , Figure 5 As shown, in this embodiment, a grout stop plug 5 is installed on the grouting anchor 1 at the opening of the anchor hole 2, and the top of the grout stop plug 5 covers the bottom outside of the rubber sleeve 3.

[0031] Understandably, the grout stopper 5 is a sealing element installed at the opening of the anchor bolt hole 2. The diameter of the tail end of the grout stopper 5 is larger than the diameter of the anchor bolt hole 2, which can seal the anchor bolt hole 2 and allow the grout to penetrate into the rock mass around the anchor bolt hole 2.

[0032] In this embodiment, the top of the grout stop plug 5 covers the bottom outer circumference of the rubber sleeve 3, providing support and load-bearing for the rubber sleeve 3; this prevents the rubber sleeve 3 from deforming towards the orifice under the thrust of the grout. In this embodiment, the top of the grout stop plug 5 can be tightly fitted to the bottom outer circumference of the rubber sleeve 3 by interference fit or hot melt bonding, thereby providing stable support for the rubber sleeve 3.

[0033] like Figure 1 , Figure 6As shown, the grout stop plug 5 is made of frustoconical rubber or polyurethane elastomer. It is understood that the frustoconical design allows the grout stop plug 5 to undergo uniform radial expansion deformation under axial pressure, thereby fitting tightly against the opening of the anchor bolt hole 2 and sealing it. Furthermore, in this embodiment, the frustoconical rubber or polyurethane elastomer used in the grout stop plug 5 can also guide stress dispersion through changes in geometry and elastomer, enabling gradual deformation and sealing under grouting pressure, thus avoiding localized stress concentration.

[0034] More specifically, this embodiment uses a frustoconical rubber or polyurethane elastomer plug 5 to achieve a synergistic response between the material and the structure under grouting pressure. The frustoconical structure causes the plug 5 to gradually expand along the contour of the anchor hole under axial pressure, forming a smooth sealing interface from the inside out. The flexibility of the molecular chains of the rubber or polyurethane elastomer ensures that the energy is evenly distributed during the expansion process, providing sufficient radial support to seal the anchor hole 2, and controlling the pressure acting on the hole wall within the range of rock compressive strength, preventing the hole opening from breaking, causing grouting failure and forming a waste hole.

[0035] In this embodiment, the inner diameter of the grout stop plug 5 is adapted to the outer diameter of the grouting anchor rod 1. During installation, the grout stop plug 5 is sleeved on the outer periphery of the grouting anchor rod 1 and sleeved on the bottom outer periphery of the rubber sleeve 3 and interference-fitted with the rubber sleeve 3.

[0036] In practical applications, if the outer side of the grout stop plug 5 lacks a reliable external fixing structure, it is prone to axial displacement under the action of grouting pressure, which leads to the failure of the hole sealing of the anchor bolt hole 2 and causes grout leakage. At the same time, the unstable movement of the grout stop plug 5 may aggravate the risk of rock mass fracture at the hole opening, making it impossible to maintain the stability of grouting pressure and affecting the fracture reinforcement effect.

[0037] In this embodiment, an external thread is provided on the outer periphery of the grouting anchor 1 extending out of the anchor hole 2, such as... Figure 1 , Figure 3 , Figure 5 As shown, on the side of the grout-stopping plug 5 away from the anchor bolt hole 2, a washer 6 and a nut 7 are fitted onto the grouting anchor bolt 1, so that the nut 7 is connected to the external thread on the outer circumference of the grouting anchor bolt 1. At the same time, the inner diameter of the washer 6 is equal to the outer diameter of the grouting anchor bolt 1, and the outer diameter of the washer 6 is larger than the diameter of the grout-stopping plug 5. During installation, the grout-stopping plug 5 is first fitted onto the grouting anchor bolt 1. After the grouting anchor bolt 1 is inserted into the anchor bolt hole 2, the grout-stopping plug 5 is inserted into the opening of the anchor bolt hole 2. Then, the washer 6 and the nut 7 are sequentially fitted onto the grouting anchor bolt 1. By rotating the nut 7, a pre-tightening force is applied, so that the grout-stopping plug 5 fits tightly against the rock mass outside the opening of the anchor bolt hole 2.

[0038] Understandably, tightening the nut 7 onto the grout stop plug 5 applies a preload to the grout stop plug 5, ensuring it adheres tightly to the inner wall of the anchor bolt hole 2. The nut 7 not only provides stable axial support for the grout stop plug 5 but also applies a controllable preload to stabilize its position. The external thread of the grouting anchor bolt 1 and the nut 7 form an adjustable axial constraint, firmly pressing the grout stop plug 5 against the borehole opening and preventing the grouting pressure from pushing the grout stop plug out of the hole.

[0039] Furthermore, the outer diameter of the washer 6 is larger than the diameter of the grout stopper 5, which increases the support area. When tightening the nut 7, the washer 6 can evenly distribute the load, preventing the grout stopper 5 from deforming or breaking due to localized stress concentration. In this embodiment, the washer 6 and the nut 7 are fixing components used to provide axial restraint, and can be implemented by combining a standard flat washer made of metal with a hexagonal nut.

[0040] It should be noted that in practical applications, due to the dimensional inhomogeneity of rock mass fissures or pores, the length of the rubber sleeve 3 needs to be coordinated and matched with the size of the anchor hole 2 to avoid insufficient sealing range or excessive extension, resulting in incomplete fissure sealing or material redundancy, which would affect the reliability of grouting reinforcement.

[0041] In this embodiment, the length of the rubber sleeve 3 ranges from 400 to 500 mm, which is 2 to 2.5 times the diameter of the anchor hole 2. This size design is to ensure that the coverage area of ​​the rubber sleeve 3 can adapt to rock fracture areas of different depths and scales, avoiding sealing failure or material redundancy problems caused by length mismatch. This ensures that the rubber sleeve 3, under geological conditions with uneven scales, will not be too short to cover deep fractures, nor too long to cause material waste or hinder the opening action of the spring clips, thereby improving the reliability and efficiency of grouting reinforcement.

[0042] In addition, in this embodiment, the bottom quarter section of the rubber sleeve 3 is bonded and fixed to the grouting anchor 1 to ensure a stable connection with the grouting anchor 1 and to prevent the rubber sleeve 3 from separating from the grouting anchor 1 during the process of increasing pressure; the connection point between the T-shaped pressure tongue spring 4 and the grouting anchor 1 is located above the connection point between the rubber sleeve 3 and the grouting anchor 1 (in the direction close to the grout outlet 11).

[0043] In this embodiment, as Figure 1 , Figure 3 , Figure 5 As shown, the tail end of the grouting anchor rod 1 is connected to the grouting pipe 8. One end of the grouting pipe 8 is threaded to the grouting connector 9. The outer diameter of the grouting pipe 8 is the same as the outer diameter of the grouting anchor rod 1. After the grouting pipe 8 is aligned with the axis of the grouting anchor rod 1, the grouting connector 9 is moved toward the grouting anchor rod 1. The grouting connector 9 is threaded to the grouting pipe 8 and the grouting anchor rod 1. The other end of the grouting pipe 8 is connected to the grouting equipment (such as a grouting pump).

[0044] In this embodiment, the grouting pipe 8 is threaded to the grouting connector 9 at one end. This means the grouting connector 9 is threaded onto the external thread on the outer circumference of the end of the grouting pipe 8. When the grouting connector 9 is tightened toward the external thread of the grouting anchor rod 1, the grouting anchor rod 1 and the grouting pipe 8 can be connected together, providing reliable mechanical fixation and sealing performance to prevent loosening. The outer diameter of the grouting pipe 8 is the same as the outer diameter of the grouting anchor rod 1 to eliminate steps or gaps at the connection interface and avoid grout leakage paths due to dimensional differences.

[0045] It should also be noted that the grouting joint 9 is made of high-strength and corrosion-resistant alloy steel or nylon-reinforced composite material, which has good impact resistance and wear resistance. The grouting anchor 1 and the grouting pipe 8 are connected and sealed through the grouting joint 9 to prevent grout from leaking from the connection under grouting pressure, which would cause material waste, make it difficult to establish and maintain stable grouting pressure, and affect the overall reinforcement effect and construction efficiency.

[0046] like Figure 1 , Figure 3 , Figure 5 As shown, an anchoring agent 12 is applied to the outer periphery of the end of the grouting anchor rod 1 furthest from the grouting pipe 8 for connection with the anchor rod hole 2. The anchoring agent 12 can be an epoxy resin-based or cement-based anchoring agent, the purpose of which is to enhance the interfacial bonding force between the grouting anchor rod 1 and the surrounding rock through chemical bonding.

[0047] like Figure 1 , Figure 3 , Figure 5 As shown, multiple grout outlet holes 11 are opened on the side of the rubber sleeve 3 away from the anchor hole 2 (two in this embodiment). Each outlet hole 11 includes multiple grout outlet holes 11 evenly arranged around the circumference of the grouting anchor 1. Grout flows out from the grout outlet holes 11 and fills the anchor hole 2. It should be noted that the grout outlet holes 11 of adjacent outlet holes are staggered axially on the side wall of the grouting anchor 1, which can reduce the single-point impact pressure. In addition, the multiple grout outlet holes 11 are evenly and staggeredly distributed along the axial direction of the side wall of the grouting anchor rod 1, which can avoid uneven distribution of grout or blockage of local grout outlet holes 11, thereby affecting the accuracy of the dissolution triggering time of the water-soluble film 43, reducing the sealing efficiency of the connected crack 21, and even aggravating the risk of grout leakage. The multiple grout outlet holes 11 are evenly and staggeredly distributed along the axial direction of the side wall of the grouting anchor rod 1, which can release grout from different heights and directions, promote the grout to flow out in a dispersed manner, avoid concentrated flushing along the same radial plane, and ensure that the dissolution process of the water-soluble film is uniformly spread in the circumferential direction.

[0048] In this embodiment, the diameter of the grout outlet 11 is 8 mm, which can be formed by drilling, stamping, or casting. This size balances the grouting flow rate and hydrodynamic 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.

[0049] In this embodiment, the water-soluble film 43 is used to coat the transverse elastic pieces 41 of adjacent T-shaped tongue depressors 4. Specifically, the water-soluble film 43 is a water-soluble PVA film, heat-sealed into a flat capsule shape, and coats the transverse elastic pieces 41 of adjacent T-shaped tongue depressors 4. Specifically, the water-soluble film 43 has a thickness of 60 μm, a length and width of 20 mm × 10 mm, a single capsule weight of 1.0 ± 0.05 g, and a bulk density of 0.85 g / cm³. -3 .

[0050] It should be noted that water-soluble PVA film is a soluble film material based on polyvinyl alcohol. It is prepared by using PVA materials with different molecular weights or modification processes to adapt to the dissolution rate requirements under different environments. The flat capsule is a flat capsule-shaped encapsulation structure formed by a heat-sealing process, and its size design is adapted to the transverse spring layout of the T-shaped depressor.

[0051] Example 2 This embodiment discloses a construction method for a grouting anchor to prevent grout leakage, which applies a grouting anchor to prevent grout leakage disclosed in Embodiment 1. The specific steps include: A T-shaped pressure tongue spring 4 is fixedly connected (e.g., welded) in the circumferential direction of the grouting anchor rod 1. The transverse spring 41 of the T-shaped pressure tongue spring 4 is pressed into a ring shape and covered and adhered by a water-soluble film 43. Then, a rubber sleeve 3 is fitted on the outside of the T-shaped pressure tongue spring 4, and the bottom of the rubber sleeve 3 is fixedly connected to the grouting anchor rod 1. Then, a grout stop plug 5 is fitted on the outside of the bottom of the rubber sleeve 3. Drill anchor bolt hole 2 and clean the hole. Place grouting anchor bolt 1, which is equipped with T-type pressure tongue spring 4, rubber sleeve 3 and grout stop plug 5, into anchor bolt hole 2. Install gasket 6 and nut 7 on grouting anchor bolt 1 and connect grouting pipe 8. Grout is injected into the grouting anchor 1. The grout dissolves the water-soluble film 43, releasing the horizontal elastic piece 41 and the vertical elastic piece 42, which open the top of the rubber sleeve 3 and press against the hole wall of the anchor hole 2, blocking the grout from flowing to the connecting crack 21. This completes the sealing while avoiding crushing the opening of the anchor hole 2. At the same time, it allows part of the grout to stay in the connecting crack 21, thus reinforcing the connecting crack.

[0052] In practical applications, to avoid excessive pressure during grouting leading to severe pressure on the borehole opening, the grouting pressure is increased only after it rises and stabilizes at the set pressure (1.5 MPa in this embodiment). Specifically, during initial grouting, the grout flows out from the outlet hole 11, filling the anchor bolt hole 2 and slowly flowing towards the connecting fissure 21. After the grout soaks the rubber sleeve 3 and dissolves the water-soluble film 43, the rubber sleeve 3, under the elastic force of the T-shaped pressure tongue and the filling effect of the grout, seals the grout channel of the connecting fissure 21. Afterward, the pressure of the anchor bolt hole 2 stabilizes. When the pressure rises to 1.5 MPa, the pressure is slowly increased to the set permeation pressure (4 MPa in this embodiment) to allow the grout to permeate into the rock mass surrounding the anchor bolt hole 2. When the pressure stabilizes at the set permeation pressure and the flow rate stabilizes at the set flow rate (e.g., 0.5 L / min) for a set time (e.g., 3 min), it indicates that stable grouting has been completed in the anchor bolt hole 2, and the grouting is then stopped.

[0053] Understandably, by setting an initial pressure stabilization, excessive grouting pressure is avoided to prevent the orifice from being crushed. After stabilization, the pressure is slowly increased to the set permeation pressure. During this process, the grout in the connecting fracture 21 gradually solidifies and reinforces the connecting fracture 21, ensuring the stability of the orifice.

[0054] In some implementations, a quick-setting grout is used to accelerate the process of reinforcing the connected cracks 21.

[0055] 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 grout running preventing grouting anchor rod, characterized by, include: Grouting anchor rod, wherein the grouting anchor rod is inserted into the anchor rod hole and the top of the grouting anchor rod has a grout outlet hole; A rubber sleeve, the tail end of which is fixedly connected to the grouting anchor rod, and the rubber sleeve is located between the grout outlet hole and the connecting fissure in the anchor rod hole; T-shaped depressor springs, several of the T-shaped depressor springs are evenly connected to the grouting anchor rod in the circumferential direction inside the rubber sleeve. The T-shaped depressor springs include a horizontal spring, a vertical spring is fixedly connected to the center of the horizontal spring, and the tail end of the vertical spring is fixedly connected to the outer wall of the grouting anchor rod and is covered by the rubber sleeve. The horizontal spring pieces of adjacent T-shaped depressor spring pieces are pressed together in a clockwise or counterclockwise manner to form a ring shape, so that the vertical spring pieces are in a compressed state facing the grouting anchor rod; the horizontal spring pieces pressed together are covered and bonded by a water-soluble film. The elastic force of the T-shaped tongue depressor is greater than the shrinkage performance of the rubber sleeve.

2. A grout-loss-preventing grouting anchor rod according to claim 1, characterized in that A grout stopper is fitted onto the grouting anchor at the opening of the anchor hole, and the top of the grout stopper covers the bottom outside of the rubber sleeve.

3. A grout-loss-preventing grouting anchor rod as claimed in claim 2, characterized in that The grout stopper is made of frustoconical rubber or polyurethane elastomer.

4. A grouting anchor bolt for preventing grout leakage as described in claim 3, characterized in that, The grouting anchor rod extends out of the anchor rod hole and has an external thread. A washer and a nut are fitted on the grouting anchor rod. The nut is connected to the external thread on the outer periphery of the grouting anchor rod. The outer diameter of the washer is larger than the diameter of the grout stop plug.

5. A grouting anchor bolt for preventing grout leakage as described in claim 1, characterized in that, The length of the rubber sleeve ranges from 400 to 500 mm, and the bottom quarter section of the rubber sleeve is bonded and fixed to the grouting anchor rod; the connection point between the T-shaped pressure tongue spring and the grouting anchor rod is located above the connection point between the rubber sleeve and the grouting anchor rod.

6. The grouting anchor bolt for preventing grout leakage as described in claim 1, characterized in that, The tail end of the grouting anchor is connected to the grouting pipe, and the outer circumference of one end of the grouting pipe is connected to the grouting joint. The outer diameter of the grouting pipe is the same as the outer diameter of the grouting anchor. The grouting joint is threadedly connected to the grouting pipe and the grouting anchor. The other end of the grouting pipe is connected to the grouting equipment.

7. A grouting anchor bolt for preventing grout leakage as described in claim 1, characterized in that, An anchoring agent is applied to the outer periphery of the end of the grouting anchor rod away from the grouting pipe.

8. A grouting anchor bolt for preventing grout leakage as described in claim 1, characterized in that, The grout outlet holes are opened in multiple channels on the side of the rubber sleeve away from the anchor bolt hole, and each channel includes multiple grout outlet holes evenly arranged along the circumference of the grouting anchor bolt.

9. A construction method for a grouting anchor bolt for preventing grout leakage as described in any one of claims 1-8, characterized in that, The specific steps include: T-shaped pressure tongue springs are fixedly connected to the grouting anchor rod. The horizontal springs of the T-shaped pressure tongue springs are pressed into a ring shape and covered and adhered by a water-soluble film. Then, a rubber sleeve is fitted on the outside of the T-shaped pressure tongue springs, and the bottom of the rubber sleeve is fixedly connected to the grouting anchor rod. Then, a grout stop plug is fitted on the outside of the bottom of the rubber sleeve. Drill and clean the anchor bolt holes. Place the grouting anchor bolt, equipped with a T-shaped pressure tongue spring, rubber sleeve, and grout stop plug, into the anchor bolt hole. Install the gasket and nut on the grouting anchor bolt, then connect the grouting pipe and inject grout into the grouting anchor bolt.

10. The construction method of a grouting anchor bolt for preventing grout leakage as described in claim 9, characterized in that, During grouting, once the grouting pressure rises and stabilizes at the set pressure, the pressure is slowly increased to the set permeation pressure to allow the grout to permeate into the rock mass around the anchor bolt hole. When the pressure stabilizes at the set permeation pressure and the flow rate stabilizes at the set flow rate for the set time, the grouting is stopped.

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