A quick-plug hollow grouting anchor cable and precise fixed-length anchor grouting method

Abstract

The application discloses a hollow grouting anchor cable with quick plug-in and a precise fixed-length anchor grouting method, and is especially suitable for the field of anchor rod support of strong dilatancy and long rheological rock mass. The hollow grouting anchor cable rod body is composed of a hollow steel pipe and eight steel strands wound outside the hollow steel pipe. A hole sealing device and a grouting joint capable of quick plug-in are arranged at the tail of the rod body, so that the grouting efficiency is improved, and the grouting sealing effect is ensured. A grouting outlet device is arranged in the middle of the anchor cable rod body. According to the crack condition, the grouting outlet device is provided with grouting limiting devices on the front and back sides, so that four kinds of precise fixed-length anchoring modes are realized, and the anchoring structure has certain buffer and pressure relief characteristics on the basis of stronger bearing capacity. An anchoring agent limiting device for limiting the flow of anchoring agent is arranged at the head of the anchor cable, so that the reliability of anchoring is improved. In addition, the application proposes that various grouting parameters should be acquired in real time, the grouting quality should be controlled, and the abnormal grouting area should be diagnosed and treated in time, so that precise grouting is realized. The application has the advantages of simple structure, convenient operation and remarkable application effect.

Description

Technical Field

[0001] This invention relates to a quick-connect hollow grouting anchor cable and a precise fixed-length anchoring method, which is particularly suitable for support in difficult projects such as deep high-stress, soft rock, strongly mined roadways and special underground locations, and belongs to the field of anchor bolt support. Background Technology

[0002] As coal mining depths increase, lithology deteriorates, and the tunneling environment becomes increasingly complex, leading to severe deterioration and fracturing of the surrounding rock and poor tunnel maintenance. Therefore, controlling the surrounding rock in tunnels with complex geological conditions is an urgent engineering challenge that needs to be addressed.

[0003] Rock grouting support, through surrounding rock modification and reconstruction, is an effective means of maintaining and controlling this type of roadway. However, existing hollow grouting anchors generally suffer from the following problems: First, the connection process between the grouting anchor and the grouting pipeline is complex, often requiring 2-3 workers to perform the connection, which seriously affects tunneling efficiency. The complex procedures restrict the widespread adoption of the rock grouting technology. Second, the single-hole sealing effect of hollow grouting anchors is generally poor, and grout easily flows out of the hole. Third, the current grouting technology lacks pressure relief in the grouting pipeline. The device has several drawbacks. First, it increases pressure and fracturing the coal seam. Second, workers are easily injured by the grouting pipes during the removal of the grouting pipeline after grouting is completed. Third, current grouting generally involves full-length anchoring of the cable, which enhances the deformation resistance of the surrounding rock but reduces the amount of pressure relief deformation of the anchor cable. This can easily lead to the failure of the overall support structure under deep rock masses with strong expansion and long rheological conditions. Fourth, current grouting management is crude and cannot accurately and objectively evaluate the grouting quality and effect of each grouting anchor (cable), which is detrimental to the safe production management of coal mines. Summary of the Invention

[0004] Technical problem: The purpose of this invention is to overcome the shortcomings of existing technologies and provide a quick-connect hollow grouting anchor cable and a precise fixed-length anchoring method, which has a simple structure, is easy to operate, and is low in cost.

[0005] Technical Solution: To achieve the above technical objectives, the present invention provides a quick-connect hollow grouting anchor cable, with a locking device and a tray at the tail end. It includes a grouting anchor cable rod body, with a hollow grouting steel pipe inside. Multiple strands of steel wire are twisted and wound around the outside of the hollow grouting steel pipe. A grouting joint is provided at the tail end of the hollow grouting steel pipe, and a grout-stopping cap is provided at the grouting joint for sealing. An anchor ring sleeve is fitted near the end of the grouting anchor cable rod body to seal the flow of anchoring resin. The grouting anchor cable rod body between the anchor ring sleeve and the tray is decorated as needed. A sealing device is provided at intervals to limit the grouting range. The sealing device and the anchor ring sleeve are provided with a grout outlet on the grouting anchor rod that communicates with the inside of the hollow grouting steel pipe. The sealing device includes a flexible tube sleeved on the grouting anchor rod. Two opposing anchor claws are sleeved on the front and rear ends of the flexible tube on the grouting anchor rod. The anchor claws are truncated cone structures with one end larger than the other, and the smaller end of the truncated cone structure of the anchor claw is positioned opposite the flexible tube. A grout-stopping cotton is provided on the grouting anchor rod to seal the grouting slurry at the larger end of the anchor claw at the front end of the flexible tube.

[0006] Furthermore, the slurry outlet is formed by cutting off the hollow grouting steel pipe and the solid steel strand at a preset slurry outlet position and disconnecting them by a certain distance. During the disconnection distance, an expansion nut is set between the twisted and wound multiple strands of steel strand. The expansion nut opens a gap in the externally wound steel strand. This results in good slurry discharge effect, prevents the slurry outlet pipe from being blocked when the slurry is too thick, and facilitates the escape of air in the slurry, thus avoiding the formation of holes in the grouting body.

[0007] Furthermore, when the grouting section is only from the sealing device to a specific position on the grouting anchor rod, a grout-stopping cotton is set at a specific position between the sealing device and the anchor ring sleeve on the grouting anchor rod to restrict the grouting area, so that the area between the sealing device and the grout-stopping cotton is the grouting area, achieving fixed-length grouting. At this time, the grout outlet is set on the grouting anchor rod between the sealing device and the newly set grout-stopping cotton.

[0008] Furthermore, a rigid tube is provided between the anchor claw at the rear end of the sealing device and the tray to support and fix the position of the sealing device. The length of the rigid tube can be adjusted as needed. The grout stop cap is made of biodegradable plastic, which reduces pollution in the mining area. The grout stop cap can be removed and reused after grouting is completed.

[0009] Furthermore, the grouting joint is equipped with a sealing ring at the end to ensure that the grouting equipment does not leak grout during grouting, the grouting joint is equipped with a groove in the middle to prevent the grouting pipe from falling off, and the grouting joint is equipped with a threaded section at the tail end that matches the tail end of the hollow steel pipe.

[0010] Furthermore, the grout-stopping cotton has a two-layer strip structure. A material that expands when exposed to water but does not generate heat is applied between the two layers of grout-stopping cotton, including a putty-type water-swelling water-stopping strip. The grout-stopping cotton is applied to the grouting anchor rod in a counterclockwise direction opposite to the rotation direction of the drilling rig. Adhesive devices are provided at both ends of the grout-stopping cotton, and it self-adhedes after being wrapped.

[0011] Furthermore, the steel strands that are twisted and wrapped around the outside of the traditional anchor cable rod are replaced with 8 strands. By modifying the steel material and increasing the number of steel strands, the strength and elongation of the hollow grouting anchor cable are improved, thus avoiding a significant reduction in the mechanical properties of the hollow grouting anchor cable due to its hollow structure.

[0012] A precise fixed-length anchoring method for the aforementioned quick-connect hollow grouting anchor cable comprises the following steps: The grouting pipeline is connected, and the grouting mechanism uses high-pressure hoses. The connection sequence is as follows: the mixing tank is connected to the grouting pump, the grouting pump is connected to the hollow grouting anchor cable, and flow, pressure and density sensors are installed in the pipeline and connected in parallel with an overflow valve. If the grouting pressure exceeds the warning value, the grout will return to the mixing tank through the overflow valve. According to the anchor cable support design requirements, hollow grouting anchor cable holes are drilled in the coal and rock mass; Determine the amount of anchoring agent as needed, and determine the position of the anchor ring sleeve through calculation; Precisely locate the initiation and expansion areas of borehole wall cracks; Based on the precise location of the crack, adjust the number and location of the sealing devices installed in the hollow grouting anchor cable, the location of the grout outlet, and the length of the rigid pipe. Anchoring agent is placed in the hollow grouting anchor cable hole, and then the hollow grouting anchor cable is used to push the anchoring agent into the bottom of the borehole to achieve resin anchoring. Pushing the rigid pipe moves the conical anchor claw on one side of the sealing device. Since the conical anchor claw on the other side of the sealing device is restricted by the grout-stopping cotton, the hose in the middle is squeezed and bulged, which achieves the effect of sealing the grouting section. Finally, insert the tray and lock into the end of the hollow grouting anchor cable in sequence, apply pre-tightening force to the lock with the tension pump, lock the tray with the lock and make the hollow grouting anchor cable bear the load; Add water to the mixing tank and turn on the mixing pump. Pour the grouting material into the grouting tank according to the water-cement ratio and complete the mixing. Remove the grout stop cap, connect and fix the grouting equipment pipeline to the grouting joint, and then turn on the grouting pump to start grouting the hollow grouting anchor cable; The grout flows out from the grout outlet, and the grout injection range is limited by the grout-stopping cotton installed in the sealing device. At the same time, the grouting pressure, flow rate, density and other parameters are acquired in real time by the sensors installed on the grouting pipeline to control the grouting quality. After grouting is completed, disconnect the pipes near the grouting joint, cover with a grout stop cap, wait for the grout to solidify, and then begin grouting the next anchor cable.

[0013] Furthermore, if grouting is to be performed on a fixed crack area in the middle of the anchor cable, grout-stopping cotton is installed on the hollow grouting anchor rod between the sealing device and the anchor ring sleeve as needed, and anchor claws are installed at the front and rear ends of the grout-stopping cotton to achieve precise fixed-length anchoring.

[0014] Furthermore, abnormal grouting areas are diagnosed in a timely manner. Specifically, they are classified according to the product of grouting volume and grouting pressure. If the product is lower than a certain value, it is considered an abnormal grouting. A small grouting volume or a grouting pressure close to 0 indicates the worst grouting effect. Afterward, secondary grouting or adjustment of the grouting water-cement ratio is carried out. When the grouting pressure exceeds the preset dangerous grouting pressure value, the grout will flow out through the overflow valve and flow back into the grouting mixing tank through the pipeline to prevent excessive pressure from splitting the rock mass.

[0015] Beneficial effects: This invention overcomes the drawbacks of traditional hollow grouting anchor cable connection processes, such as complex connection processes, poor single-hole sealing effect, extensive grouting management, and weak adaptability to deformation and pressure relief. It can adapt to complex environments with strong expansion and long-term rheological changes, and has the following advantages compared with existing technologies: 1) High efficiency and reliability: A plastic cap is installed on the outside of the grouting joint to prevent the grouting pipe from being blocked during the transportation of the grouting anchor cable and the grouting in the tunnel. The joint is connected to the hollow pipe by threading and glue. This joint solves the problems of complicated and time-consuming connection between the grouting anchor cable and the grouting pipeline, freeing up 2-3 underground workers, improving the tunneling efficiency of the anchoring process, and avoiding the easy damage to the joint and the reduction in the strength of the grouting anchor cable caused by traditional welded grouting heads. In addition, the outer ring of the hollow grouting anchor cable of this invention is made of 8 strands of steel strand, using low-carbon steel material with higher strength and toughness, avoiding the problem of low strength and elongation caused by the hollow structure of traditional hollow grouting anchor cables.

[0016] 2) Precise fixed-length anchoring is achieved, with significant pressure relief characteristics: Before constructing the anchor cables, the development information of surrounding rock fissures is detected by digital detection methods. Using the adjustable-length rigid pipes, flexible pipes, grout-stopping cotton and anchor claws in this invention, four types of fixed-length anchoring can be achieved. While improving the strength of the surrounding rock, it also has certain buffering and pressure relief characteristics, which allows the support structure to reserve a certain amount of deformation to fully adapt to the influence of mining stress and achieve long-term stability of the roadway.

[0017] 3) Excellent single-hole sealing effect: This invention employs multiple processes, including flexible hoses, anchor claws, and grout-stopping cotton, to seal the hole wall. A putty-type water-swellable sealing strip is installed within the grout-stopping cotton layer. Upon contact with water, it expands 2-3 times its original size, filling all irregular surfaces, cavities, and gaps in the hole wall. Simultaneously, it generates significant contact pressure, completely preventing grout from leaking out of the hole wall. Furthermore, the expansion rate is moderate; the sealing strip will not affect the construction effect due to excessive expansion when exposed to water during the initial solidification of the grout or during installation.

[0018] 4) Quantitative Grouting: This invention solves the problem of difficult quality control in traditional grouting. By installing sensors for density, pressure, and flow rate in the grouting pipeline, it obtains information such as the grouting volume, grouting pressure, and water-cement ratio of each grouting anchor cable in real time and accurately. This fundamentally avoids situations such as inadequate grouting construction and grouting "faking," ensuring grouting quality. Furthermore, the monitoring information enables quantitative grouting of the roof and real-time adjustment of the grout water-cement ratio, laying a solid foundation for precise control of the surrounding rock. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the hollow grouting anchor cable in this invention; Figure 2 This is a schematic diagram of the grouting joint of the present invention; Figure 3 This is a schematic diagram of the conical anchor claw of the present invention; Figure 4 This is a schematic diagram of the structure of the anti-slurry cap of the present invention; Figure 5 This is a schematic diagram of the structure of the anchor ring sleeve of the present invention; Figure 6 This is an internal view of the hollow steel pipe tail section of the grouting anchor cable of the present invention; Figure 7 This is a diagram of the grouting pump pipeline of the present invention; Figure 8 These are schematic diagrams of four fixed-length anchoring methods. In the diagram, (a) is a schematic diagram of full anchoring using a single sealing device, (b) is a schematic diagram of full anchoring using a single sealing device adjusted with a rigid pipe, (c) is a schematic diagram of fixed-length injection anchoring using a sealing device, grout-stopping cotton, and a rigid pipe, and (d) is a schematic diagram of fixed-length injection anchoring using a sealing device and grout-stopping cotton.

[0020] In the diagram: 1-Grouting cap; 2-Grouting joint; 2-1-Sealing ring; 2-2-Slot; 2-3-Threaded section; 3-Lock; 4-Rigid pipe; 5-Tray; 6-Anchor claw; 7-Hose; 8-Grouting cotton; 9-Grouting outlet; 10-Expanding nut; 11-Hollow grouting anchor cable; 12-Anchor ring sleeve. Detailed Implementation

[0021] An embodiment of the present invention will be further described below with reference to the accompanying drawings: like Figure 1 As shown, a quick-connect hollow grouting anchor cable is provided with a locking device 3 and a tray 5 at the tail end. It includes a grouting anchor cable rod body, inside which is a hollow grouting steel pipe. Multiple strands of steel wire are twisted and wound around the outside of the hollow grouting steel pipe. A grouting joint 2 is provided at the tail end of the hollow grouting steel pipe. A grout-stopping cap 1 with a sealing function is provided at the grouting joint 2 via threads. Figure 4 As shown; near the end of the grouting anchor cable rod, an anchor ring sleeve 12 is fitted to seal the flow of anchoring resin, such as... Figure 5 As shown, the grouting anchor rod between the anchor ring sleeve 12 and the tray 5 is provided with sealing devices at intervals to limit the grouting range as needed. A grout outlet 9 communicating with the interior of the hollow grouting steel pipe is provided on the grouting anchor rod between the sealing device and the anchor ring sleeve 12. The sealing device includes a flexible hose 7 sleeved on the grouting anchor rod, and two opposing anchor claws 6 are sleeved at the front and rear ends of the flexible hose 7 on the grouting anchor rod. Figure 3 As shown, the anchor claw 6 is a truncated cone structure with one end larger than the other. The smaller end of the truncated cone structure of the anchor claw 6 is positioned relative to the flexible hose 7. At the larger end of the anchor claw 6, which is close to the front end of the flexible hose 7, there is a grout-stopping cotton 8 on the grouting anchor rod to seal the grouting slurry.

[0022] The grout outlet 9 is formed by cutting off the hollow grouting steel pipe and solid steel strand at a preset grout outlet position and disconnecting them by a certain distance. Within this disconnected distance, an expanding nut 10 is installed between the twisted and wound multiple strands of steel strand. The expanding nut 10 opens a gap in the externally wound steel strand, resulting in good grout outlet performance. This prevents the grout from clogging the outlet pipe when the grout is too thick and facilitates the escape of air from the grout, avoiding the formation of holes in the grout body. When the grouting section is only from the sealing device to a specific position on the grouting anchor rod, a grout-stopping cotton 8 is installed at a specific position between the sealing device and the anchor ring sleeve 12 on the grouting anchor rod to limit the grouting area. This makes the area between the sealing device and the grout-stopping cotton 8 the grouting area, achieving fixed-length grouting. In this case, the grout outlet 9 is located on the grouting anchor rod between the sealing device and the newly installed grout-stopping cotton 8.

[0023] A rigid pipe 4 is provided between the anchor claw 6 at the rear end of the sealing device and the tray 5 to support and fix the position of the sealing device. The length of the rigid pipe 4 can be adjusted as needed. The grout stop cap 1 is made of biodegradable plastic, reducing pollution in the mining area. Furthermore, the grout stop cap 1 can be removed and reused after grouting is completed. Figure 6 As shown, the hollow steel pipe of the grouting anchor cable has an internal thread at the tail end that matches the grouting joint 2.

[0024] like Figure 2 As shown, the end of the grouting joint 2 is provided with a sealing ring 2-1 to ensure that the grouting equipment does not leak grout during grouting. The quick-connect grouting joint 2 is provided with a groove 2-2 in the middle to prevent the grouting pipe from falling off. The tail of the grouting joint 2 is provided with a threaded section 2-3 that matches the tail of the hollow steel pipe.

[0025] The grout-stopping cotton 8 has a two-layer strip structure. A material that expands when exposed to water but does not generate heat is applied between the two layers of grout-stopping cotton 8, including a putty-type water-swelling water-stopping strip. The grout-stopping cotton 8 is applied to the grouting anchor rod in a counterclockwise direction opposite to the rotation direction of the drilling rig. Adhesive devices are provided at both ends of the grout-stopping cotton 8, and it self-adhedes after being wrapped.

[0026] The traditional steel strands twisted and wrapped around the outside of the anchor rod are replaced with 8 strands. The strength and elongation of the hollow grouting anchor 11 are improved by modifying the steel material and increasing the number of steel strands, thus avoiding a significant reduction in the mechanical properties of the hollow grouting anchor 11 due to its hollow structure.

[0027] like Figure 7 As shown, a precise fixed-length anchoring method for quick-connect hollow grouting anchor cables is described, with the following steps: The grouting pipeline is connected, and the grouting mechanism uses high-pressure hoses. The connection sequence is as follows: the mixing tank is connected to the grouting pump, the grouting pump is connected to the hollow grouting anchor cable 11, and flow, pressure and density sensors are installed in the pipeline and connected in parallel with an overflow valve. If the grouting pressure exceeds the warning value, the grout will return to the mixing tank through the overflow valve. In accordance with the anchor cable support design requirements, 11 hollow grouting anchor cables were drilled in the coal and rock mass; The amount of anchoring agent is determined as needed, and the position of anchor ring sleeve 13 is determined by calculation. Precisely locate the initiation and expansion areas of borehole wall cracks; Based on the precise location of the crack, adjust the number and location of the sealing devices installed in the hollow grouting anchor cable 11, the location of the grout outlet 9, and the length of the rigid pipe 4. Anchoring agent is placed in the hole of the hollow grouting anchor cable 11, and then the anchoring agent is pushed into the bottom of the borehole by the hollow grouting anchor cable 11 to achieve resin anchoring. Pushing the rigid pipe 4 will push the conical anchor 6 on one side of the sealing device to move. Since the conical anchor 6 on the other side of the sealing device is restricted by the grout-stopping cotton 8, the hose 7 in the middle will be squeezed and bulged, thus sealing the grouting section. Finally, the tray 5 and the lock 3 are inserted into the tail end of the hollow grouting anchor cable 11 in sequence. The tension pump is used to apply a pre-tightening force to the lock 3 to lock the tray and make the hollow grouting anchor cable 11 bear the load. Add water to the mixing tank and turn on the mixing pump. Pour the grouting material into the grouting tank according to the water-cement ratio and complete the mixing. Remove the grout stop cap 1, connect and fix the grouting equipment pipeline to the grouting joint 2, and then turn on the grouting pump to start grouting into the hollow grouting anchor cable 11; The grout flows out from the grout outlet 9. The grouting range is limited by the grout-stopping cotton 8 with a sealing device. At the same time, the grouting pressure, flow rate, density and other parameters are obtained in real time by the sensors installed on the grouting pipeline to control the grouting quality. After grouting is completed, disconnect the pipes near the grouting joint, cover with grout stop cap 1, wait for the grout to solidify, and start grouting the next grouting anchor cable.

[0028] like Figure 8As shown, if grouting is performed on a fixed crack area in the middle of the anchor cable, grout-stopping cotton 8 is installed on the hollow grouting anchor rod between the sealing device and the anchor ring sleeve 12 as needed, and anchor claws 6 are installed at the front and rear ends of the grout-stopping cotton 8 to achieve precise fixed-length anchoring. Figures a and b show the implementation effect of full anchoring with a single sealing device, while figures c and d show the implementation effect of fixed-length anchoring in a specific section with the addition of grout-stopping cotton 8 and anchor claws 6. Abnormal grouting areas are diagnosed promptly. Specifically, they are classified according to the product of grouting volume and grouting pressure. If the product is lower than a certain value, it indicates abnormal grouting. A small grouting volume or grouting pressure approaching 0 indicates the worst grouting effect. Afterwards, secondary grouting or adjustment of the grouting water-cement ratio is carried out. When the grouting pressure exceeds the preset dangerous grouting pressure value, the grout will flow out through the overflow valve and back into the grouting mixing tank through the pipeline to prevent excessive pressure from fracturing the rock mass.

Claims

1. A quick-connect hollow grouting anchor cable, with a locking device (3) and a tray (5) at the tail, characterized in that: The grouting anchor rod includes a hollow grouting steel pipe inside, with multiple strands of steel wire twisted and wound around the outside of the hollow grouting steel pipe. A grouting joint (2) is provided at the tail end of the hollow grouting steel pipe, and a grout-stopping cap (1) is provided at the grouting joint (2) for sealing. An anchor ring sleeve (12) is fitted near the end of the grouting anchor rod to seal the flow of the anchoring agent. Sealing devices for limiting the grouting range are provided at intervals on the grouting anchor rod between the anchor ring sleeve (12) and the tray (5) as needed. The sealing devices and the anchor ring sleeve (12)... The grouting anchor rod is provided with a grout outlet (9) that communicates with the inside of the hollow grouting steel pipe; the sealing device includes a flexible hose (7) sleeved on the grouting anchor rod, and two anchor claws (6) are sleeved on the front and rear ends of the flexible hose (7) on the grouting anchor rod. The anchor claws (6) are truncated cone structures with one end larger than the other end. The small end of the truncated cone structure of the anchor claws (6) is set opposite to the flexible hose (7); a grout-stopping cotton (8) for sealing the grout is provided on the grouting anchor rod at the large end of the anchor claws (6) at the front end of the flexible hose (7); The precise length anchoring method involves the following steps: The grouting pipeline is connected. All the connecting pipelines of the grouting mechanism are made of high-pressure rubber hoses. The connection sequence is: the mixing tank is connected to the grouting pump, the grouting pump is connected to the hollow grouting anchor cable (11), and flow, pressure and density sensors are installed in the pipeline and the overflow valve is connected in parallel. If the grouting pressure exceeds the warning value, the grout will return to the mixing tank through the overflow valve. According to the anchor cable support design requirements, hollow grouting anchor cable (11) holes were drilled in the coal and rock mass; The amount of anchoring agent is determined as needed, and the position of the anchor ring sleeve (12) is determined by calculation. Precisely locate the initiation and expansion areas of the pore wall cracks; Based on the precise location of the crack, adjust the number and location of the sealing device of the hollow grouting anchor cable (11), the location of the grout outlet (9), and the length of the rigid pipe (4); Anchoring agent is placed in the hole of the hollow grouting anchor cable (11), and then the anchoring agent is pushed into the bottom of the borehole by the hollow grouting anchor cable (11) to achieve resin anchoring. Pushing the rigid pipe (4) will push the conical anchor claw (6) on one side of the sealing device to move. Since the conical anchor claw (6) on the other side of the sealing device is restricted by the grout-stopping cotton (8), the hose (7) in the middle will be squeezed and bulged, thus achieving the effect of sealing the grouting section. Finally, insert the tray (5) and lock (3) into the end of the hollow grouting anchor cable (11) in sequence, apply pre-tightening force to the lock (3) with the tension pump, lock the tray with the lock and make the hollow grouting anchor cable (11) bear the load; Add water to the mixing tank and turn on the mixing pump. Pour the grouting material into the grouting tank according to the water-cement ratio and complete the mixing. Remove the grout cap (1), connect and fix the grouting equipment pipeline to the grouting joint (2), and then turn on the grouting pump to start grouting into the hollow grouting anchor cable (11); The grout flows out from the grout outlet (9), and the grout injection range is limited by the grout-stopping cotton (8) installed in the sealing device. At the same time, the grouting pressure, flow rate and density parameters are obtained in real time by the sensors installed on the grouting pipeline to control the grouting quality. After grouting is completed, remove the pipes near the grouting joint, cover with the grout stop cap (1), wait for the grout to solidify, and start grouting the next grouting anchor cable.

2. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: The grout outlet (9) is formed by cutting off the hollow grouting steel pipe and solid steel strand at a preset grout outlet position and disconnecting them by a certain distance. In the disconnected distance, a hole-expanding nut (10) is set between the twisted and wound multiple strands of steel strand. The hole-expanding nut (10) opens a gap in the externally wound steel strand. It has a good grout outlet effect, prevents the grout outlet pipe from being blocked when the grout is too thick, and facilitates the overflow of air in the grout, thus avoiding the formation of holes in the grout body.

3. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: When the grouting section is only from the sealing device to a specific position of the grouting anchor rod, a grout-stopping cotton (8) that restricts the grouting area is set at a specific position between the sealing device and the anchor ring sleeve (12) of the grouting anchor rod, so that the area between the sealing device and the grout-stopping cotton (8) is the grouting area, and fixed-length grouting is achieved. At this time, the grout outlet (9) is set on the grouting anchor rod between the sealing device and the newly set grout-stopping cotton (8).

4. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: A rigid pipe (4) is provided between the anchor claw (6) at the rear end of the sealing device and the tray (5) to support and fix the position of the sealing device. The length of the rigid pipe (4) can be adjusted as needed. The material of the grout stop cap (1) is biodegradable plastic, which reduces pollution in the mining area. The grout stop cap (1) can be removed and reused after grouting is completed.

5. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: The grouting joint (2) is provided with a sealing ring (2-1) at the end to ensure that the grouting equipment does not leak grout during grouting. The grouting joint (2) is provided with a groove (2-2) in the middle to prevent the grouting pipe from falling off. The grouting joint (2) is provided with a threaded section (2-3) at the tail end that matches the tail end of the hollow steel pipe.

6. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: The grout-stopping cotton (8) has a two-layer strip structure. A material that expands when exposed to water but does not generate heat is applied between the two layers of grout-stopping cotton (8), including putty-type water-swelling water-stopping strips. The grout-stopping cotton (8) is applied to the grouting anchor rod in a counterclockwise direction opposite to the rotation direction of the drilling rig. Adhesive devices are provided at both ends of the grout-stopping cotton (8), and it self-adhedes after being wrapped.

7. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: The steel strands that are twisted and wrapped around the outside of the traditional anchor rod are replaced with 8 strands. The strength and elongation of the hollow grouting anchor (11) are improved by modifying the steel material and increasing the number of steel strands, so as to avoid the hollow grouting anchor (11) from having a significant reduction in mechanical properties due to its hollowness.

8. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: If grouting is to be performed on a fixed crack area in the middle of the anchor cable, grout-stopping cotton (8) is installed on the hollow grouting anchor rod between the sealing device and the anchor ring sleeve (12) as needed, and anchor claws (6) are installed at the front and rear ends of the grout-stopping cotton (8) to achieve precise fixed-length anchoring.

9. The quick-connect hollow grouting anchor cable according to claim 1, characterized in that: For areas with abnormal grouting, timely diagnosis is crucial. Specifically, the grouting volume and grouting pressure are used to classify the grouting. If the product is lower than a certain value, it indicates an abnormal grouting. A small grouting volume or grouting pressure approaching 0 indicates the worst grouting effect. Afterward, secondary grouting or adjustment of the grouting water-cement ratio is carried out. When the grouting pressure exceeds the preset dangerous grouting pressure value, the grout will flow out through the overflow valve and flow back into the grouting mixing tank through the pipeline to prevent excessive pressure from fracturing the rock mass.

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