Anchor rod or anchor cable mounting device and method for inhibiting failure of anchoring interface

Abstract

The invention discloses an anchor rod or anchor cable mounting device and method for inhibiting failure of an anchoring interface, and relates to the technical field of roadway supporting. The device comprises an annular body, a conical protrusion structure, a pulse press-in device, a fluid flushing system and a guide stabilizer, and is suitable for various hole diameters and different surrounding rock types. The construction method using the device comprises the following steps: drilling a hole by a drilling machine to mount an anchor rod or an anchor cable, evaluating the drilling hole, determining a test environment and boundary conditions, performing a drilling hole compression test to simulate confining pressure to obtain a stress deformation response curve, and determining the bonding performance and the shear strength through a pull-out test. The size of the conical protrusion is determined by combining lithology and crustal stress characteristics, the device is installed to a drilling target section, the pulse pressing-in device is started, the conical protrusion structure is pressed into the hole wall of a drilling hole to form a continuous groove, and when a fluid washing system is started to remove dust and chippings, a guiding stabilizer is connected, so that the drilling target section is formed. It is ensured that the device retreats from a drill hole at a constant speed, cleaning operation in the hole is completed, and finally the prefabricated anchor rod is inserted to form a high-adhesion and high-shear-resistance complete anchoring structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of roadway support, and particularly provides an anchor rod or anchor cable installation device and method for inhibiting anchor interface failure. BACKGROUND

[0002] In mine roadway or tunnel support engineering, the anchor rod and anchor cable system, as one of the main support forms, directly determines the stability of the surrounding rock of the roadway and the safety of the engineering. Under the combined action of in-situ stress and mining stress, the support system frequently appears to be unanchored and fails, which seriously threatens the safety of the engineering. Especially in the deep or high-strength mining influence area, with the advance of the mining working face, the mining stress is dynamically redistributed, causing fluctuations or mutations in the original stress field of the surrounding rock, resulting in serious disturbance and plastic deformation of the surrounding rock of the roadway.

[0003] A large number of field monitoring and theoretical researches show that the borehole wall stress concentration effect caused by mining stress is significant, leading to unbalanced stress of the borehole structure, showing complex deformation modes such as axial compression, local shear or collapse, and the hole shape evolves from an ideal circle to an ellipse or irregular shape. Such deformation seriously damages the bonding continuity between the anchoring agent and the rock mass, causing the bonding force in the stress concentration area of the borehole wall to rapidly degrade, and easily inducing interface debonding, anchor rod slippage or overall anchoring failure. At the same time, the borehole is often pushed in a rotating manner during drilling operation, and the borehole wall surface is often smooth, lacking effective rough structure, and the anchoring agent is difficult to form physical engagement with the borehole wall. In addition, the drill cuttings and dust that are not cleaned up will be left in the hole cavity, forming an "isolating layer", further weakening the bonding effect of the anchoring agent and the surrounding rock, resulting in a significant decrease in the interface bonding strength.

[0004] In order to further improve the anchoring and support quality under complex surrounding rock and ground stress conditions, it is necessary to provide a comprehensive support device and method that can intervene in time during the deformation of the borehole wall, while taking into account the functions of debris cleaning and stress self-adaptive adjustment, to realize the optimization of overall anchoring effect and the continuous improvement of the safety of roadway support, and to further improve the existing support method. SUMMARY

[0005] In order to effectively reduce the debonding failure risk of the anchor rod-rock mass interface and enhance the long-term stability and reliability of the anchoring system, the present application provides an anchor rod or anchor cable installation device and method for inhibiting anchor interface failure, and the specific technical solutions are as follows:

[0006] Anchoring device for preventing anchoring interface failure, comprising a ring-shaped body, a conical protrusion structure, a pulse pressing device, a fluid flushing system and a guiding stabilizer, the inside of the ring-shaped body is a closed hydraulic chamber structure, the distribution of the oil chamber structure corresponds to the distribution of the conical protrusion structure; the oil chamber structure is connected with a hydraulic control system through a high-pressure pipeline to control the protrusion depth of each conical protrusion structure; the pulse pressing device is arranged on the high-pressure pipeline to control the hydraulic pressure; the fluid flushing system comprises a pipeline and a nozzle to perform high-pressure flushing operation; the guiding stabilizer controls the device to exit at a uniform speed and keeps the path stable.

[0007] An anchoring method for preventing anchoring interface failure, using the anchoring device for preventing anchoring interface failure, the steps of the method comprising:

[0008] S1. Drilling a hole to the designed length of the hole by using a drilling machine;

[0009] S2. Evaluating the hole by using sensors and loading devices arranged for hole compression test and pullout test to determine the test hole environment and boundary conditions;

[0010] S3. Performing hole compression test, applying simulated confining pressure to the hole, recording the axial deformation data of the hole wall at different loading stages, evaluating the trend of the hole section from circular to elliptical and the stress-induced deformation law, and determining the stress-deformation response curve;

[0011] S4. Performing anchor rod pullout test, recording the bearing capacity, slip amount and interface failure mode under different anchoring interface conditions, and analyzing the bonding performance and shear strength;

[0012] S5. Determining the protrusion size of the conical protrusion structure according to the test results;

[0013] S6. Sending the anchoring device for preventing anchoring interface failure into the target section of the hole to perform slot embedding operation;

[0014] S7. Starting the pulse pressing device to uniformly press the conical protrusion structure into the hole wall of the hole to form a continuous groove;

[0015] S8. Starting the fluid flushing system to inject high-pressure medium to clean the groove, connecting the guiding stabilizer to uniformly exit the device, and keeping the guiding stabilizer centered and guided during the entire exit process to ensure sufficient cleaning effect and no disturbance to the hole wall, and after the flushing is completed, the device is taken out as a whole;

[0016] S9. Inserting the prefabricated anchor rod or anchor cable into the groove section to embed, and forming a complete anchoring structure with high bonding and high shear resistance after the anchoring agent is coagulated.

[0017] Preferably, the drilling environment includes lithology, surrounding rock strength, fracture distribution, and in-situ stress, and strain gauges, pressure sensors, and displacement sensors are installed on the borehole wall.

[0018] Preferably, in the borehole compression test, a non-uniform confining pressure is applied to the simulated borehole to simulate ground stress and mining stress, and axial deformation data is recorded by sensors to generate stress-strain curves.

[0019] Preferably, in the anchor pull-out test, the pull-out testing machine applies a pull-out force to simulate the actual stress on the anchor, and records the bearing capacity, slippage, and interface failure mode during the pull-out process.

[0020] Preferably, the parameters of the groove include position, direction, spacing and depth, and the groove is arranged along the minor axis of the elliptical cross section. The size of the conical protrusion structure and the pulse frequency of the pulse pressing device are determined according to the design size of the groove.

[0021] Preferably, the pulse pressing device presses the conical protrusion structure into the borehole wall to form a groove at a set pulse frequency, and dynamically adjusts the pulse frequency and protrusion depth according to monitoring data.

[0022] Preferably, the drilling rig support can rotate at different angles to adapt to the angles of different anchor holes, so as to meet the construction angle requirements of various anchor holes.

[0023] Preferably, the fluid flushing system uses high-pressure water or high-pressure gas to clean dust and debris from inside the borehole.

[0024] The beneficial effects of the anchor bolt or anchor cable installation device and method for suppressing anchorage interface failure provided by the present invention include:

[0025] (1) By forming a multi-directional stress interface on the borehole wall, the problem of insufficient bonding force of the anchoring agent interface caused by the traditional smooth borehole wall is significantly improved. This structural interface can simultaneously achieve the dual functions of mechanical locking and physical interlocking, and combined with high-frequency pressing operation, the groove structure is made denser and more stable, effectively improving the integrity and anti-disturbance ability of the physical interface. Even under micro-deformation conditions, it can maintain a tight fit between the anchoring agent and the rock mass, reducing the risk of slippage or interface failure caused by shear stress concentration, thereby significantly enhancing the long-term stability of the anchoring system under complex geostress fields.

[0026] (2) A stabilizer is used to achieve uniform device deployment, effectively avoiding eccentricity and disturbance during the deployment process, ensuring coaxial stability under complex surrounding rock conditions, and improving the accuracy of the groove and the integrity of the structure. At the same time, the uniform device advancement, pulse fracturing, multi-directional groove, synchronous flushing and anchoring agent injection are seamlessly integrated into a continuous process, which not only ensures the continuity and adaptability of the operation steps, but also significantly shortens the construction time, reduces labor costs, and provides an ideal working foundation for subsequent processes.

[0027] (3) The device and method are reasonable in design, can be adapted to various hole diameters and surrounding rock conditions, and are suitable for complex supporting environments such as soft rock mass, high ground stress area, deep mine and tunnel engineering, and have good engineering universality and promotion value. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of stress analysis of a drill hole;

[0029] Figure 2 is a schematic diagram of stress analysis of a drill hole before and after deformation;

[0030] Figure 3 is a schematic diagram of an anchoring section;

[0031] Figure 4 is a schematic diagram of a compression test;

[0032] Figure 5 is a schematic diagram of a pull-out test of an anchor rod;

[0033] Figure 6 is a schematic diagram of the use of the installation device;

[0034] Figure 7 is a schematic diagram of the internal structure of the anchor rod or anchor cable installation device for inhibiting the failure of the anchoring interface;

[0035] Figure 8 is a schematic diagram of part of the structure of the anchor rod or anchor cable installation device for inhibiting the failure of the anchoring interface;

[0036] Figure 9 is a schematic diagram of the layout of the pipeline

[0037] Figure 10 is a schematic diagram of the structure of the guide stabilizer

[0038] Figure 11 is a schematic diagram of the use of the guide stabilizer;

[0039] In the drawings: 1 - anchoring agent, 2 - anchor rod, 3 - drill hole, 4 - unanchored area, 5 - before deformation of the drill hole, 6 - after deformation of the drill hole, 7 - compression zone of the anchoring agent, 8 - surrounding rock, 9 - groove, 10 - compression test system, 11 - test specimen, 12 - pull-out test system, 13 - fluid flushing system, 14 - ring-shaped body, 15 - pulse pressure device, 17 - pipeline, 18 - nut, 19 - conical protruding structure, 20 - flexible oil bladder, 21 - positioning rod, 22 - upper pressing plate, 23 - lower pressing plate, 24 - rod body, 25 - toothed pattern, 26 - controller, 27 - fixed sleeve, 28 - motor. DETAILED DESCRIPTION

[0040] In combination Figures 1 to 11A specific embodiment of an anchor rod or anchor cable installation device and method for inhibiting anchoring interface failure is shown.

[0041] An anchor rod or anchor cable installation device for inhibiting anchoring interface failure, comprising a ring-shaped body 14, a conical protrusion structure 19, a pulse pressing device 15, a fluid flushing system 13, and a guide stabilizer, the inside of the ring-shaped body 14 is a closed hydraulic chamber oil cavity structure, the distribution of the oil cavity structure corresponds to the distribution of the conical protrusion structure 19, the oil cavity distribution corresponds to the conical protrusion structure, forming an independent control unit, which can accurately adjust the extension length of each conical protrusion structure, and realize uniform expansion. A flexible oil bladder 20 is arranged in the middle of the ring-shaped body 14, an upper pressing plate 21 and a lower pressing plate 23 are arranged on the upper and lower sides of the flexible oil bladder 20 respectively, a pipeline 17 is arranged on both sides of the flexible oil bladder 20, a nut 18 is arranged at the end of the flexible oil bladder 20, and a positioning rod 21 is further arranged at the end of the ring-shaped body 14 to facilitate the connection of the guide stabilizer. The oil cavity structure is connected with a hydraulic control system through a high-pressure pipeline to control the extension length of each conical protrusion structure; the pulse pressing device 15 is arranged on the high-pressure pipeline to control the hydraulic pressure, after being pushed into the hole, the device forms a continuous and uniform groove on the hole wall by using the pulse pressing device, then the fluid flushing system 13 is started to perform high-pressure flushing during the withdrawal of the device, effectively cleaning the dust and debris remaining in the hole during the formation of the groove 9. The fluid flushing system includes a pipeline and a spray head to perform high-pressure flushing; the guide stabilizer control device controls the uniform speed of withdrawal and maintains the path stability to ensure the flushing effect and the integrity of the hole wall. The pulse pressing and medium flushing work together to make the hole wall obtain a rough and clean ideal anchoring interface. The conical protrusion structure can be withdrawn after the operation is completed to avoid blocking the flushing channel.

[0042] An anchor rod or anchor cable installation method for inhibiting anchoring interface failure, using the above-mentioned anchor rod or anchor cable installation device for inhibiting anchoring interface failure, the steps of the method include:

[0043] S1. Drilling a hole to the designed drilling length by using a drilling machine, specifically including:

[0044] S11: determining the depth, diameter and position of the drilling hole according to the geological conditions of the surrounding rock of the roadway and the supporting design requirements;

[0045] S12: drilling the hole to avoid excessive disturbance or deflection of the hole wall;

[0046] S13: preliminarily removing large-particle residues in the hole;

[0047] S14: checking the integrity, straightness and surface smoothness of the drilling hole by using a drilling peep instrument to ensure that the requirements of the subsequent processes are met.

[0048] S2. Evaluate the borehole using sensors and loading devices arranged for compression and tension tests to determine the test borehole environment and boundary conditions; specifically including:

[0049] S22: Install strain gauges, pressure sensors, and displacement sensors within and around the borehole to monitor the stress and deformation behavior of the hole wall;

[0050] S23: Set the loading range and rate for compression and tension tests based on the in-situ stress field and mining-induced stress distribution;

[0051] S24: Check and calibrate all test equipment to ensure the accuracy and reliability of data acquisition.

[0052] S3. Perform borehole compression tests to apply simulated confining pressure to the borehole, record the axial deformation data of the hole wall at different loading stages, evaluate the trend of the hole section from circular to elliptical and the stress-induced deformation law, and determine the stress-deformation response curve; specifically including:

[0053] S31: Use hydraulic loading devices to apply non-uniform confining pressure to the borehole to simulate in-situ stress and mining-induced stress;

[0054] S32: Record the axial deformation data of the hole wall in real time through sensors to generate a stress-strain curve;

[0055] S33: Based on the test data, analyze the evolution trend of the hole shape from circular to elliptical or irregular shape, and determine the high stress concentration area;

[0056] S34: Repeat the test to verify data consistency and ensure that the results can be used to guide the design of the groove.

[0057] S4. Perform anchor tension tests to record the bearing capacity, slip amount, and interface failure mode under different anchorage interface conditions, and analyze the bonding performance and shear strength; specifically including:

[0058] S41: Insert the standard test anchor into the borehole and use conventional anchoring agent for temporary anchoring to ensure the centering of the anchor;

[0059] S42: Use a tension testing machine to apply tension at a controlled rate to simulate the performance of the anchoring system under actual stress conditions;

[0060] S43: Record the bearing capacity, slip amount, and interface failure mode during tensioning, and analyze the bond strength and shear performance;

[0061] S44: Based on the test data, identify failure modes such as interface debonding, slippage, or anchoring agent rupture to provide a basis for optimizing the design of the slot.

[0062] The deformation characteristics of different surrounding rocks under in-situ and disturbed conditions are quantitatively evaluated through borehole compression and tension tests, the stress-induced hole shape evolution mechanism is clarified, and on this basis, the optimal size and spacing of the protruding structure and the notch arranged on the hole wall are determined to ensure that uniform anchoring force transmission paths are formed in any direction in the hoop direction, thereby inhibiting the debonding and sliding of the anchoring interface.

[0063] S5. Determine the protrusion size of the conical protruding structure according to the test results; specifically including:

[0064] S51: Integrate the compression test and tension test data to analyze the stress concentration area, hole deformation characteristics and interface bonding performance;

[0065] S52: According to the test results, optimize the position, direction, spacing and depth of the notch, and preferentially arrange the groove along the major axis direction of the ellipse to inhibit sliding;

[0066] S53: Convert the optimized groove parameters into device operation parameters, including the size of the conical protrusion and the pulse frequency.

[0067] S6. Install the anchor rod or anchor cable installation device that inhibits the failure of the anchoring interface into the target section of the borehole and perform the slotting operation; specifically including:

[0068] S61: Check the ring-shaped body, conical protrusion, pulse press-in device and fluid flushing system of the device to ensure that each component functions normally;

[0069] S62: Place the device into the borehole to the target section to ensure that the conical protrusion is aligned with the designed position.

[0070] S7. Start the pulse press-in device to uniformly press the conical protruding structure into the hole wall of the borehole to form a continuous groove; specifically including:

[0071] S71: Activate the hydraulic system to accurately adjust the depth of the conical protrusion to ensure uniform expansion;

[0072] S72: Start the pulse press-in device to drive the conical protrusion into the hole wall at a set frequency to form a continuous and uniform groove;

[0073] S73: Real-time monitor the hole wall stress and groove expansion during the pulse press-in process to ensure the density and uniformity of the groove;

[0074] By mechanically slotting to form a multi-directional groove structure on the hole wall and supporting fluid flushing to remove dust and debris, the engagement effect between the anchoring agent and the rock mass is significantly improved, thereby effectively reducing the risk of debonding failure of the anchor- rock interface and enhancing the long-term stability and reliability of the anchoring system.

[0075] S8. Start the fluid flushing system, inject high-pressure medium to clean the groove, connect the guide stabilizer, and withdraw the device at a constant speed. The guide stabilizer remains centered and stable throughout the withdrawal process, ensuring that the cleaning effect is sufficient and the hole wall is undisturbed. After flushing is complete, the device is removed as a whole. Specifically, it includes:

[0076] S81: After the slotting is completed, start the fluid flushing system, inject high-pressure water or gas medium through the high-pressure pipeline, and remove dust and debris from the hole;

[0077] S82: Use the guide stabilizer to control the device to flush and withdraw at a constant speed, ensuring path stability and hole wall integrity;

[0078] S83: Check the backflow of the flushing medium to confirm that the residues in the hole have been removed and the hole wall has reached a clean state;

[0079] S84: Remove the device completely from the borehole and check the device status to ensure no damage and prepare for subsequent procedures.

[0080] S9. Insert the prefabricated anchor rod or anchor cable into the groove segment, and after the anchoring agent coagulates, a complete anchoring structure with high adhesion and high shear resistance is formed. The anchor rod or anchor cable is stationary during the anchoring time to ensure that the anchoring agent is initially coagulated and embedded, and finally forms a complete anchoring structure with high adhesion and high shear resistance. This method seamlessly integrates uniform device advancement, pulse fracturing, multi-directional grooves, synchronous flushing, and anchoring agent injection into one process. This continuous workflow provides clear steps, operational continuity, and adaptability, reducing construction time and labor costs.

[0081] The device and method significantly improve the problem of insufficient interface bonding force of anchoring agent caused by traditional smooth hole wall by forming a multidirectional stress interface on the hole wall. The structural interface can realize mechanical locking and physical occlusion, significantly improving the interface stability and bonding reliability of the anchoring system. The device performs high-frequency pressing operation on the hole wall, making the groove structure more dense and stable, effectively improving the integrity and disturbance resistance of the physical interface. Even in the case of micro-deformation, the tight fit between the anchoring agent and the rock mass can be maintained, significantly reducing the risk of slip or interface failure caused by shear stress concentration, and enhancing the long-term stability of the anchoring system in complex stress fields. The use of stabilizers to achieve uniform speed of the device can effectively avoid eccentricity and disturbance during the pushing process, ensuring the coaxial stability of the device in complex surrounding rock conditions, improving the slotting precision and structural integrity, and at the same time, the uniform speed pushing and fluid flushing are synchronized, which helps to timely remove dust and debris, keep the hole clean, prevent clogging, and ensure the quality of the groove, providing a good working basis for subsequent pulse fracturing and anchoring agent injection. In addition, the device and method are designed reasonably and can be adapted to various hole diameters and surrounding rock conditions, suitable for complex support environments such as soft rock mass, high stress area, deep mine and tunnel engineering, and have good engineering universality and promotion value.

[0082] Of course, the above description is not a limitation of the present application, and the present application is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present application should also be within the scope of the present application.

Claims

1. An anchor rod or cable installation device that inhibits failure of the anchoring interface, characterized in that, The application relates to a device for preventing anchoring interface failure, which comprises a ring-shaped body, a conical protruding structure, a pulse pressing device, a fluid flushing system and a guiding stabilizer.

2. A method of installing an anchor rod or cable to inhibit failure of the anchorage interface, characterised in that, The method comprises the following steps: S1. drilling a hole to a designed length by using a drilling machine; S2. evaluating the hole by using sensors and loading devices arranged for compression and pulling tests to determine the test hole environment and boundary conditions; S3. performing a hole compression test to apply simulated confining pressure to the hole, record axial deformation data of the hole wall at different loading stages, evaluate the trend of the hole section from a circular shape to an elliptical shape and stress-induced deformation law, and determine a stress-deformation response curve; S4. performing an anchor pulling test to record the bearing capacity, slip amount and interface failure mode under different anchoring interface conditions, and analyze the bonding performance and shear strength; S5. determining the protruding interval and size of the conical protruding structure according to the test results; S6. sending the device for preventing anchoring interface failure into a target section of the hole to perform a slot embedding operation; S7. starting the pulse pressing device to uniformly press the conical protruding structure into the hole wall to form a continuous groove; S8. starting the fluid flushing system to inject high-pressure medium to clean the groove, connecting the guiding stabilizer to uniformly exit the device, and keeping the guiding stabilizer centered and guided during the entire exiting process to ensure sufficient cleaning effect and no disturbance to the hole wall, and taking out the device after the flushing is completed; S9. inserting a prefabricated anchor rod or anchor cable into the groove section to embed the anchor rod or anchor cable with the anchor agent, and forming a complete anchoring structure with high bonding and high shear strength after setting.

3. A method of installing an anchor rod or cable with suppressed interfacial failure, according to claim 2, wherein The drilling machine drills a hole according to the designed hole length, diameter and construction position.

4. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein The hole environment includes lithology, surrounding rock strength, fracture distribution and ground stress, and strain gauges, pressure sensors and displacement sensors are installed on the hole wall.

5. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein In the hole compression test, non-uniform confining pressure is applied to the simulated hole to simulate ground stress and mining stress, axial deformation data are recorded by sensors, and a stress-strain curve is generated.

6. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein In the anchor pulling test, a pulling testing machine applies a pulling force to simulate the actual stress of the anchor rod, and the bearing capacity, slip amount and interface failure form during the pulling process are recorded.

7. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein The groove parameters include position, direction, interval and depth, the groove is arranged along the long axis direction of the elliptical section, the size of the conical protruding structure and the pulse frequency of the pulse pressing device are determined according to the designed size of the groove.

8. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein The pulse pressing device presses the conical protruding structure into the hole wall to form a groove at a set pulse frequency, and dynamically adjusts the pulse frequency and protruding depth according to the monitoring data.

9. A method of installing an anchor rod or cable with suppressed interfacial failure according to claim 2, wherein The fluid flushing system uses high pressure water or high pressure gas to clean dust and debris from the borehole.

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