Soft rock anchor cable anchoring structure and soft rock anchor cable anchoring method

Abstract

The present invention relates to the technical field of coal mine tunnel support, and in particular to a soft rock anchor cable anchoring structure and a soft rock anchor cable anchoring method. The soft rock anchor cable anchoring structure comprises: an anchor cable drilling hole, which is a straight hole constructed in soft surrounding rock; a hollow anchor cable, which is provided with a grouting hole along its axial direction, and the head end of the hollow anchor cable is connected to a grouting pump for outputting an anchoring agent; a hole sealer, which is provided on the hollow anchor cable, and when the hollow anchor cable is deeply inserted into the anchor cable drilling hole, the hole sealer is used to interference fit between the outer surface of the hollow anchor cable and the inner wall of the anchor cable drilling hole. This scheme is used to solve the defect of insufficient anchoring force of the anchor cable in the prior art, and realize the anchoring effect of the improved anchor cable in the soft and broken rock layer.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine tunnel support, and in particular to a soft rock anchor cable anchoring structure and a soft rock anchor cable anchoring method. Background Art

[0002] The support effect of coal mine tunnels is directly related to personnel safety and production efficiency.

[0003] The soft rock tunnel support technology mainly adopts anchor cable support and bolt cable support. However, the traditional anchor cable support and bolt cable support scheme has the problem of insufficient anchoring force. The rock layer of the anchor cable drilling hole is weak and broken, resulting in the anchoring force of the resin anchor cable in some mines being only 100kN, which is far lower than the maximum breaking force of the anchor cable, and cannot exert the high strength and high stiffness performance that the support material should have, resulting in poor support effect.

[0004] In order to effectively solve the problem of soft rock tunnel support, improve the support effect of anchor cable and anchor rod, and break through the limitations of existing technology, it is urgent to explore solutions to improve the anchoring force of anchor cables. Summary of the invention

[0005] The present invention provides a soft rock anchor cable anchoring structure and a soft rock anchor cable anchoring method, which are used to solve the defect of insufficient anchor cable anchoring force in the prior art, improve the anchoring effect of the anchor cable in the soft and broken rock layer, ensure that the high strength and high stiffness performance of the support structure can be fully utilized, thereby ensuring the safe, efficient and green mining of coal mine tunnels.

[0006] The present invention provides a soft rock anchor cable anchoring structure, comprising: an anchor cable drill hole, which is a straight hole constructed in soft surrounding rock; a hollow anchor cable, wherein the hollow anchor cable is provided with grouting holes along its axial direction, and the head end of the hollow anchor cable is connected to a grouting pump for outputting an anchoring agent; a hole sealer, which is arranged on the hollow anchor cable, and when the hollow anchor cable penetrates into the anchor cable drill hole, the hole sealer is used for interference fit between the outer surface of the hollow anchor cable and the inner wall of the anchor cable drill hole.

[0007] According to one embodiment of the present invention, the sealer has an expansion structure; the sealer is connected to a resin tube and is connected to an injection and pressure device through the resin tube; the injection and pressure device is used to inject water or gas into the expansion structure of the sealer through the resin tube.

[0008] According to one embodiment of the present invention, the sealer is converted into an expanded state after water or gas is injected; in the expanded state, the pressure in the expanded structure of the sealer is 1 MPa to 3 MPa.

[0009] According to one embodiment of the present invention, when the hollow anchor cable penetrates into the anchor cable borehole, the distance between the installation position of the hole sealer on the hollow anchor cable and the end of the hollow anchor cable is less than or equal to the distance between the installation position and the orifice of the anchor cable borehole.

[0010] According to one embodiment of the present invention, the depth of the anchor cable drilling hole is at least 200mm to 300mm less than the length of the hollow anchor cable; and / or the diameter of the anchor cable drilling hole is 32mm, and the diameter of the hollow anchor cable is smaller than the diameter of the anchor cable drilling hole.

[0011] The present invention also provides a soft rock anchor cable anchoring method, which is used to operate the soft rock anchor cable anchoring structure of the above-mentioned embodiment to perform support operations in soft rock tunnels; the method comprises: constructing an anchor cable borehole on the wall of the soft rock tunnel; deeply inserting a hollow anchor cable equipped with a sealer into the anchor cable borehole; fixing the hollow anchor cable to the inner wall of the anchor cable borehole through the sealer; and pumping an anchoring agent into the anchor cable borehole through the hollow anchor cable.

[0012] According to one embodiment of the present invention, the step of constructing an anchor cable drilling hole on the wall of a soft rock tunnel includes: measuring and determining the length of the hollow anchor cable; determining the depth of the anchor cable drilling hole according to the length of the hollow anchor cable, the depth being 200 mm to 300 mm less than the length of the hollow anchor cable; and constructing a straight anchor cable drilling hole with a diameter of 32 mm on the wall of the soft rock tunnel according to the determined depth.

[0013] According to one embodiment of the present invention, the step of inserting the hollow anchor cable equipped with a hole sealer deep into the anchor cable borehole includes: installing the hole sealer with an expansion structure at a position 2m away from the end of the hollow anchor cable; pushing the hollow anchor cable equipped with the hole sealer in a non-expanded state to the bottom of the anchor cable borehole along the axial direction of the anchor cable borehole.

[0014] According to one embodiment of the present invention, the step of fixing the hollow anchor cable to the inner wall of the anchor cable borehole through the hole sealer includes: using a resin tube connected to the hole sealer, using high-pressure water or gas to expand the expansion structure of the hole sealer to a pressure of 1-3MPa, so that the hole sealer fits tightly to the inner wall of the anchor cable borehole; closing the resin tube to maintain the expansion state of the hole sealer.

[0015] According to one embodiment of the present invention, the step of pumping anchoring agent into the anchor cable borehole includes: connecting the hollow anchor cable to a grouting pump; mixing two-component anchoring agents in a predetermined proportion, and pumping the anchoring agent to the bottom of the anchor cable borehole through the grouting hole of the hollow anchor cable; controlling the injection pressure, and stopping the injection when the injection pressure reaches a set pressure value; after the anchoring agent is completely cured, tensioning the hollow anchor cable, applying a pre-tightening force, and completing the soft rock tunnel support operation.

[0016] The soft rock anchor cable anchoring structure and the soft rock anchor cable anchoring method provided by the invention are suitable for anchor cable support and anchor rod cable support in soft surrounding rock tunnels in coal mines, especially for surrounding rocks with poor anchorability.

[0017] The combination of hollow anchor cables and hole sealers effectively solves the problem of insufficient anchoring force of traditional anchor cables in soft and broken rock formations. The hollow anchor cables in this structure are designed with grouting holes, allowing the anchoring agent to be directly injected into the rock space around the borehole, ensuring that the anchoring agent can be fully filled and solidified in the rock cracks and holes, enhancing the mechanical interlocking effect between the anchor cable and the surrounding rock, and having a certain bonding force, which can bond the anchor cable body to the anchored coal rock. This greatly improves the anchoring strength.

[0018] In addition, the design of the sealer ensures a tight interference fit between the hollow anchor cable and the inner wall of the anchor cable borehole, which not only prevents the loss of the anchoring agent, but also plays a role of prestressing, so that the anchoring agent can exert greater pressure on the surrounding rock during the solidification process, further improving the support and anchoring effect. Through this method, effective reinforcement of soft rock tunnels can be achieved, the deformation amount and duration of the tunnel can be reduced, the renovation frequency can be reduced, and ultimately the safety and efficiency of coal mining can be guaranteed. This solution provides a more reliable technical means to solve the support problem of soft rock tunnels under complex geological conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a comparative schematic diagram of the anchor cable drilling hole and the hollow anchor cable of the soft rock anchor cable anchoring structure provided by the present invention.

[0021] Figure 2 It is a structural schematic diagram of a hollow anchor cable and a hole sealer of a soft rock anchor cable anchoring structure provided by the present invention.

[0022] Figure 3It is a schematic diagram of the installation structure of the soft rock anchor cable anchoring structure provided by the present invention.

[0023] Figure 4 It is a structural schematic diagram of the soft rock anchor cable anchoring structure provided by the present invention in the state of injected anchoring agent.

[0024] Figure 5 It is a schematic flow chart of the soft rock anchor cable anchoring method provided by the present invention.

[0025] Reference numerals: 10. Soft rock tunnel wall; 11. Anchor cable drilling hole; 20. Hollow anchor cable; 21. Grouting hole; 22. Sealer; 23. Resin tube; 24. Anchoring agent. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. It should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0028] The support of soft rock tunnels faces many challenges, especially those under complex and difficult conditions. The commonly used anchor cables with a diameter of more than 20 mm, such as anchor cables with a diameter of 21.8 mm, have a breaking load of up to 582 kN. However, in actual applications, the anchoring force of anchor cables in soft rock tunnels is often only between 100 kN and 200 kN, which means that the anchor cable strength is only utilized by 17% to 34%, which seriously affects the support effect. In order to improve the anchoring force, the current practice is to use grouting anchoring in the anchoring section, but this leads to low anchoring efficiency, cumbersome process flow and increased costs, and it cannot be tensioned in time, which is not conducive to the control of initial surrounding rock deformation. In addition, as the core component of tunnel support, the construction efficiency of anchor cables directly affects the tunnel excavation speed, thereby restricting the mining and excavation of mines. Therefore, it is an urgent need to solve the anchoring force problem of anchor cables while realizing the rapid construction of high prestressed and high anchoring force anchor cables.

[0029] The patent of the present invention proposes a soft rock anchoring scheme for the above-mentioned problems, which aims to overcome the influence of loose and broken anchor cable drilling holes. It is suitable for anchor cable support and anchor rod cable support in soft surrounding rock tunnels in coal mines, especially in surrounding rock environments with poor anchorability, and can effectively improve the overall performance and safety of the support system. This scheme installs a sealer at a certain distance from the end of the hollow anchor cable, and uses the hollow tube of the anchor cable to directly pump a two-component anchoring agent into the bottom of the borehole. The anchoring agent has an appropriate viscosity and is not easy to penetrate into the surrounding rock, forming an effective extrusion pressure between the hollow anchor cable and the borehole wall. Among them, the bonding force and extrusion force of the two-component anchoring agent work together to significantly improve the anchoring force of the anchor cable.

[0030] Combine the following Figures 1 to 5 The specific implementation methods of the soft rock anchor cable anchoring structure and the soft rock anchor cable anchoring method of the present invention are described.

[0031] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the present invention provides a soft rock anchor cable anchoring structure, comprising: an anchor cable borehole 11, a straight hole constructed in soft surrounding rock; a hollow anchor cable 20, the hollow anchor cable 20 is provided with a grouting hole 21 along its axial direction, and the head end of the hollow anchor cable 20 is connected to a grouting pump for outputting an anchoring agent 24; a sealer 22, which is arranged on the hollow anchor cable 20, and when the hollow anchor cable 20 penetrates into the anchor cable borehole 11, the sealer 22 is used to interference fit between the outer surface of the hollow anchor cable 20 and the inner wall of the anchor cable borehole 11.

[0032] Specifically, this soft rock anchor cable anchoring structure is designed by designing the hollow anchor cable 20 to have an internal channel, so that the anchoring agent 24 can be directly injected into the bottom of the anchor cable borehole 11 from the ground or the underground workstation through a grouting pump. The grouting hole 21 on the hollow anchor cable 20 allows the anchoring agent 24 to evenly penetrate and fill the gap between the anchor cable and the borehole wall under pressure, and fill any possible tiny cracks or voids. The sealer 22 is located at a specific position of the hollow anchor cable 20 (such as 2 meters away from the end), which not only plays a role in fixing the hollow anchor cable 20, but also ensures that the anchoring agent 24 will not be easily lost, and the anchoring agent 24 is confined to an effective area for solidification. This design increases the contact area and bonding strength between the anchoring agent 24 and the surrounding rock, thereby enhancing the anchoring force of the anchor cable, while reducing the waste of the anchoring agent 24 that may occur in traditional methods.

[0033] In addition, in order to further improve the support effect and construction efficiency, the present invention preferably uses a high-performance, fast-hardening two-component anchor 24 to shorten the curing time of the anchor 24, so that the anchor cable can reach the working prestressed state faster, which is conducive to timely control of surrounding rock deformation. In addition, an automated control system can be introduced to monitor and adjust parameters during the grouting process, such as pressure, flow, etc., to ensure that the anchor 24 is evenly distributed and optimize the anchoring effect. For more complex geological conditions, a monitoring component can also be integrated on the hollow anchor cable 20 to provide real-time feedback on the stress condition of the anchor cable so that appropriate maintenance measures can be taken.

[0034] According to a soft rock anchor cable anchoring structure of the present invention, the sealer 22 has an expansion structure; the sealer 22 is connected to a resin tube 23, and is connected to an injection and pressure device through the resin tube 23; the injection and pressure device is used to inject water or gas into the expansion structure of the sealer 22 through the resin tube 23. Specifically, the sealer 22 can form a tight interference fit with the inner wall of the borehole after the hollow anchor cable 20 penetrates into the anchor cable borehole 11 through the expansion mechanism. The sealer 22 is connected to a resin tube 23, and is connected to the injection and pressure device through the resin tube 23; the injection and pressure device is used to inject water or gas into the expansion structure of the sealer 22 through the resin tube 23 to achieve expansion.

[0035] When the injection and pressure device starts working, water or gas is injected into the expansion structure of the sealer 22 through the resin tube 23. As water or gas is injected, the expansion structure of the sealer 22 gradually expands, forcing the outer surface of the sealer 22 to be close to the inner wall of the anchor cable borehole 11, thereby forming a strong mechanical locking effect. The expansion and locking process not only effectively prevents the loss of the anchor 24 before solidification, but also provides additional pressure for the anchor 24, helping it to better fill the tiny cracks in the surrounding rock and enhance the bonding force between the anchor 24 and the surrounding rock. In addition, due to the close combination of the sealer 22 with the inner wall of the borehole after expansion, the shear resistance and overall stability of the entire support system are also improved.

[0036] According to a soft rock anchor cable anchoring structure of the present invention, the sealer 22 is converted into an expanded state after water or gas is injected; in the expanded state, the pressure in the expanded structure of the sealer 22 is 1MPa to 3MPa. Specifically, when water or gas is injected into the expanded structure of the sealer 22, the pressure gradually increases until it reaches and is maintained between 1MPa and 3MPa. This preferred pressure range is intended to ensure that the sealer 22 can effectively expand and form a tight interference fit with the inner wall of the anchor cable borehole 11, while avoiding damage to the sealer 22 or the borehole due to excessive pressure.

[0037] According to a soft rock anchor cable anchoring structure of the present invention, when the hollow anchor cable 20 penetrates into the anchor cable borehole 11, the distance between the installation position of the hole sealer 22 on the hollow anchor cable 20 and the end of the hollow anchor cable 20 is less than or equal to the distance between the installation position and the orifice of the anchor cable borehole 11. Specifically, when the hollow anchor cable 20 penetrates into the anchor cable borehole 11, the distance between the installation position of the hole sealer 22 on the hollow anchor cable 20 and the end of the hollow anchor cable 20 is less than or equal to the distance between the installation position and the orifice of the anchor cable borehole 11. The hole sealer 22 is located near the end of the hollow anchor cable 20, and can form an effective barrier when injecting the anchoring agent 24 to prevent the anchoring agent 24 from flowing downward and flowing out of the borehole. Since the hole sealer 22 is relatively far from the orifice, this allows the operator to perform grouting and other operations in a relatively safe position, reducing the risk of working directly near the orifice. At the same time, the reasonable position setting of the hole sealer 22 simplifies the construction process, reduces the construction difficulty, and improves work efficiency.

[0038] According to a soft rock anchor cable anchoring structure of the present invention, the depth of the anchor cable borehole 11 is at least 200mm to 300mm less than the length of the hollow anchor cable 20, ensuring that when the hollow anchor cable 20 touches the bottom, part of the hollow anchor cable 20 remains outside the hole. This part of the exposed hollow anchor cable 20 is convenient for connecting a grouting pump and other equipment, simplifying construction operations and improving efficiency. On the other hand, the diameter of the anchor cable borehole 11 is preferably 32mm, and the diameter of the hollow anchor cable 20 is smaller than the diameter of the anchor cable borehole 11. The hollow anchor cable 20 with a smaller diameter can be more easily inserted into the anchor cable borehole 11 with a larger diameter. The standard 32mm drilling diameter is suitable for the construction requirements of most soft rock tunnels, and also leaves room for the possible adjustment of the anchor cable diameter under special geological conditions, thereby increasing the application flexibility of the anchoring structure.

[0039] The soft rock anchor cable anchoring method provided by the present invention is described below. The soft rock anchor cable anchoring method described below and the soft rock anchor cable anchoring structure described above can be referred to each other.

[0040] like Figure 5As shown, the present invention also provides a soft rock anchor cable anchoring method, which is used to operate the soft rock anchor cable anchoring structure of the above embodiment to perform support operations in soft rock tunnels. The method includes the following steps: Step 110, construct anchor cable borehole 11 on the soft rock tunnel wall 10. Specifically, use appropriate drilling equipment to drill a hole of appropriate diameter (such as 32 mm) at a predetermined position according to design requirements, and set the depth to be slightly smaller than (usually 200 mm to 300 mm shorter) the length of the hollow anchor cable 20 to ensure that a sufficient portion of the hollow anchor cable 20 remains outside the hole after installation.

[0041] Step 120, insert the hollow anchor cable 20 with the hole sealer 22 installed deep into the anchor cable borehole 11. Specifically, the hollow anchor cable 20 with the pre-installed hole sealer 22 is inserted into the borehole until the bottom of the anchor cable contacts the bottom of the borehole, while ensuring that a section of the top of the hollow anchor cable 20 is left outside the borehole for subsequent connection of the grouting pump.

[0042] Step 130, the hollow anchor cable 20 is fixed to the inner wall of the anchor cable borehole 11 by the hole sealer 22. Specifically, the hole sealer 22 is located between the anchor cable and the borehole. When pressure is injected, the hole sealer 22 expands and fits tightly to the inner wall of the borehole, thereby achieving a firm fixation between the anchor cable and the borehole and preventing the anchoring agent 24 from overflowing from the hole.

[0043] Step 140, pumping anchoring agent 24 into anchor cable borehole 11 through hollow anchor cable 20. Specifically, using a grouting pump connected to the top of hollow anchor cable 20, the anchoring agent 24 is pumped into the borehole through the hollow anchor cable 20 until the entire borehole space is filled and the anchor cable is wrapped to achieve the best anchoring effect. After the anchoring agent 24 is cured, it can greatly enhance the bonding force between the anchor cable and the surrounding rocks, ensuring the stability and safety of the soft rock tunnel.

[0044] Further, according to a soft rock anchor cable anchoring method of the present invention, the steps of constructing an anchor cable borehole 11 on a soft rock tunnel wall 10 include: Step 111, measure and determine the length of the hollow anchor cable 20. Specifically, use a measuring tool (such as a tape measure or a laser rangefinder) to accurately measure the actual length of the hollow anchor cable 20, and record the data to ensure the accuracy of subsequent operations.

[0045] Step 112, determine the depth of the anchor cable drilling hole 11 according to the length of the hollow anchor cable 20, which is 200mm to 300mm less than the length of the hollow anchor cable 20. Specifically, based on the measured length of the hollow anchor cable 20, 200mm to 300mm is subtracted to calculate the target depth of the anchor cable drilling hole 11, ensuring that after the hollow anchor cable 20 is fully inserted, part of it is still retained outside the hole, which is convenient for connecting equipment such as a grouting pump, and at the same time provides sufficient expansion space for the hole sealer 22.

[0046] Step 113, according to the determined depth, construct a straight anchor cable drill hole 11 with a diameter of 32 mm on the soft rock tunnel wall 10. Specifically, use professional drilling equipment suitable for soft rock conditions, according to the pre-calculated depth and the preferred 32 mm diameter standard, accurately construct the straight anchor cable drill hole 11 on the soft rock tunnel wall 10. During the drilling process, the drill bit needs to be kept perpendicular to the tunnel wall to ensure that the drilling quality meets the design requirements, so as to smoothly insert the hollow anchor cable 20 and achieve a good anchoring effect.

[0047] Further, according to a soft rock anchor cable anchoring method of the present invention, the step of inserting the hollow anchor cable 20 equipped with the hole sealer 22 deep into the anchor cable borehole 11 includes: Step 121, install the hole sealer 22 with expansion structure at a position 2m away from the end of the hollow anchor cable 20. Specifically, the position 2m away from the end of the hollow anchor cable 20 can be marked on the hollow anchor cable 20, and then the hole sealer 22 can be accurately installed at this mark. Ensure that the hole sealer 22 is firmly connected to the hollow anchor cable 20, and check whether the resin tube 23 is correctly connected to the injection and pressure device, so that water or gas can be smoothly injected to expand the hole sealer 22 later.

[0048] Step 122, along the axial direction of the anchor cable borehole 11, push the hollow anchor cable 20 equipped with the hole sealer 22 in a non-expanded state to the bottom of the anchor cable borehole 11. Specifically, the operator needs to push the hollow anchor cable 20 along the axial direction of the anchor cable borehole 11 to ensure that the hole sealer 22 and the anchor cable smoothly enter the borehole until the end of the hollow anchor cable 20 touches the bottom of the borehole. During this process, the straightness of the hollow anchor cable 20 should be maintained to avoid twisting or bending to prevent the hole sealer 22 from being caused unnecessary friction or damage by the inner wall of the borehole. In addition, attention should be paid to moderate force when pushing to ensure that the hole sealer 22 is in a non-expanded state until it reaches the predetermined position.

[0049] Further, according to a soft rock anchoring method of the present invention, the step of fixing the hollow anchor 20 to the inner wall of the anchor borehole 11 through the hole sealer 22 includes: Step 131, through the resin tube 23 connected to the sealer 22, use high-pressure water or gas to expand the expansion structure of the sealer 22 to a pressure of 1-3MPa, so that the sealer 22 fits tightly against the inner wall of the anchor cable borehole 11. Specifically, the operator starts the injection pressure device, injects high-pressure water or gas into the expansion structure of the sealer 22 through the resin tube 23, and gradually increases the pressure until it reaches and stabilizes between 1-3MPa. This pressure range ensures that the sealer 22 can fully expand and form an interference fit with the inner wall of the borehole, providing a strong mechanical locking effect, while avoiding damage to the sealer 22 or the borehole due to excessive pressure. During this process, the pressure gauge needs to be closely monitored to ensure that the pressure value is accurate.

[0050] Step 132, seal the resin tube 23 to maintain the expansion state of the hole sealer 22. Specifically, after confirming that the hole sealer 22 has successfully expanded and is tightly attached to the inner wall of the borehole, immediately close the valve or other control device on the resin tube 23 to cut off the water or gas supply, thereby locking the expansion state of the hole sealer 22. To ensure that this state is maintained for a long time, the interface of the resin tube 23 can be reinforced with sealing materials to prevent leakage, so as to ensure that the hole sealer 22 always maintains effective expansion and fixing during the entire support period.

[0051] Further, according to a soft rock anchoring method of the present invention, the step of pumping an anchoring agent 24 into the anchor borehole 11 includes: Step 141, connect the hollow anchor cable 20 to the grouting pump. Specifically, use a special connector to firmly connect the top of the hollow anchor cable 20 to the grouting pump, and ensure that the connection is well sealed to prevent leakage during the grouting process. Check all connection parts and prepare to start the grouting operation after confirming that they are correct.

[0052] Step 142, mix the two-component anchor 24 according to a predetermined ratio, and pump the anchor 24 to the bottom of the anchor borehole 11 through the grouting hole 21 of the hollow anchor 20. Specifically, the two-component anchor 24 is accurately mixed according to the optimal ratio determined by the experiment. Start the grouting pump, and evenly inject the mixed anchor 24 into the bottom of the anchor borehole 11 through the grouting hole 21 inside the hollow anchor 20 until the entire borehole space is filled. This process needs to maintain continuity and stability to ensure that the anchor 24 fully fills and wraps the hollow anchor 20.

[0053] Step 143, control the grouting pressure, and stop grouting when the grouting pressure reaches the set pressure value. Specifically, the grouting pressure is continuously monitored during the grouting process, and a safe and effective pressure range is usually set. When the pressure gauge shows that the preset value is reached, the grouting is immediately stopped to ensure that the anchor 24 can fully fill all gaps in the borehole under appropriate pressure.

[0054] Step 144: After the anchoring agent 24 is completely cured, the hollow anchor cable 20 is tensioned and preloaded to complete the soft rock tunnel support operation. Specifically, after waiting for the anchoring agent 24 to be completely cured, a tensioning device is used to apply a predetermined preload to the hollow anchor cable 20 to establish an initial stress state, which can effectively enhance the bonding force between the anchor cable and the surrounding rock, provide an immediate support effect, and provide a guarantee for long-term stability. After tensioning is completed, check and record various parameters to ensure the safety and reliability of the support system. Then proceed to the next anchor cable construction.

[0055] Compared with the traditional soft rock anchor cable anchoring method, the soft rock anchor cable anchoring method of the present invention significantly improves the construction efficiency and practicality, while simplifying the construction process and reducing the cost. The method can flexibly adapt to different on-site surrounding rock conditions, accurately adjust the injection pressure according to the actual situation, and ensure the best anchoring effect. By adopting easy-to-operate technical means, such as expansion and fixation of the hole sealer 22 and direct grouting of the hollow anchor cable 20, not only the construction difficulty and technical requirements are reduced, but also the success rate of anchor cable construction is effectively improved. In addition, the method realizes the rapid tensioning of the anchor cable, and the preload can be applied after the anchoring agent 24 is cured, providing immediate and efficient support for the surrounding rock, ensuring the realization of high preload. In summary, the soft rock anchor cable anchoring method provided by the present invention not only optimizes the construction process and reduces the overall construction cost, but also provides a reliable guarantee for the safe and efficient support of coal mine tunnels.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or mode are included in at least one embodiment or mode of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or modes in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or modes described in this specification and the features of the different embodiments or modes, without contradiction.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A soft rock anchor cable anchoring structure, characterized in that: include: Anchor cable drilling is a straight hole constructed in soft surrounding rock; A hollow anchor cable, wherein the hollow anchor cable is provided with grouting holes along its axial direction, and the head end of the hollow anchor cable is connected to a grouting pump for outputting an anchoring agent; The hole sealer is arranged on the hollow anchor cable. When the hollow anchor cable penetrates into the anchor cable borehole, the hole sealer is used for interference fit between the outer surface of the hollow anchor cable and the inner wall of the anchor cable borehole.

2. The soft rock anchor cable anchoring structure according to claim 1, characterized in that: The hole sealer has an expansion structure; The hole sealer is connected to a resin tube and is connected to the injection and pressure device through the resin tube; The injection device is used to inject water or gas into the expansion structure of the hole sealer through the resin tube.

3. The soft rock anchor cable anchoring structure according to claim 2, characterized in that: The hole sealer is converted into an expanded state after water or gas is injected; In the expanded state, the pressure in the expanded structure of the sealer is 1 MPa to 3 MPa.

4. The soft rock anchor cable anchoring structure according to any one of claims 1 to 3, characterized in that: When the hollow anchor cable penetrates deeply into the anchor cable borehole, the distance between the installation position of the hole sealer on the hollow anchor cable and the end of the hollow anchor cable is less than or equal to the distance between the installation position and the opening of the anchor cable borehole.

5. The soft rock anchor cable anchoring structure according to claim 4, characterized in that: The depth of the anchor cable drilling hole is at least 200 mm to 300 mm less than the length of the hollow anchor cable; And / or, the diameter of the anchor cable drill hole is 32 mm, and the diameter of the hollow anchor cable is smaller than the diameter of the anchor cable drill hole.

6. A soft rock anchor cable anchoring method, characterized in that: Used to operate the soft rock anchor cable anchoring structure according to any one of claims 1 to 5 to perform support operations in soft rock tunnels; Methods include: Construction of anchor cable drilling holes on the soft rock tunnel wall; Inserting a hollow anchor cable with a hole sealer installed deep into the anchor cable borehole; The hollow anchor cable is fixed to the inner wall of the anchor cable borehole through the hole sealer; Anchoring agent is pumped into the anchor cable borehole through the hollow anchor cable.

7. The soft rock anchor cable anchoring method according to claim 6, characterized in that: The steps of constructing anchor cable drilling holes on the soft rock tunnel wall include: Measuring and determining the length of the hollow anchor cable; Determining the depth of the anchor cable drilling according to the length of the hollow anchor cable, the depth being 200 mm to 300 mm less than the length of the hollow anchor cable; According to the determined depth, straight anchor cable holes with a diameter of 32 mm are constructed on the soft rock tunnel wall.

8. The soft rock anchor cable anchoring method according to claim 6, characterized in that: The step of inserting the hollow anchor cable with the hole sealer into the anchor cable borehole comprises: Install the hole sealer with an expansion structure at a position 2m away from the end of the hollow anchor cable; The hollow anchor cable equipped with the hole sealer in a non-expanded state is pushed to the bottom of the anchor cable borehole along the axial direction of the anchor cable borehole.

9. The soft rock anchor cable anchoring method according to claim 8, characterized in that: The step of fixing the hollow anchor cable to the inner wall of the anchor cable borehole through the hole sealer comprises: Using a resin tube connected to the hole sealer, the expansion structure of the hole sealer is expanded to a pressure of 1-3 MPa using high-pressure water or gas, so that the hole sealer fits tightly against the inner wall of the anchor cable borehole; The resin tube is sealed to maintain the expanded state of the hole sealer.

10. The soft rock anchor cable anchoring method according to any one of claims 6 to 9, characterized in that: The step of pumping the anchoring agent into the anchor cable borehole comprises: Connecting the hollow anchor cable to a grouting pump; Mixing two components of anchoring agent according to a predetermined ratio, and pumping the anchoring agent to the bottom of the anchor cable borehole through the grouting hole of the hollow anchor cable; Controlling the filling pressure, and stopping the filling when the filling pressure reaches a set pressure value; After the anchoring agent is completely cured, the hollow anchor cable is tensioned and a pre-tightening force is applied to complete the soft rock tunnel support operation.

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