Intelligent pipe joint anchor rod anchoring force testing system and testing method
The intelligent pipe joint anchor bolt anchoring force testing system, utilizing an adaptive clamping structure and wireless sensors, solves the problem of anchoring force detection in confined spaces using existing devices, achieving efficient and accurate anchoring force testing while reducing operational complexity and data instability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANDONG GOLD MINE CO LTD XINCHENG GOLD MINE
- Filing Date
- 2026-06-17
- Publication Date
- 2026-07-14
AI Technical Summary
Existing pipe joint anchor bolt anchoring force testing devices suffer from problems such as small contact area leading to stress concentration, difficulty in adjusting axis alignment, complex structure, cumbersome operation, and unstable test data, making it difficult to efficiently and accurately test anchoring force in confined spaces.
An intelligent pipe joint anchor bolt anchoring force testing system is adopted, including an end pull-out mechanism, a gas-liquid pressurization system and wireless sensors. By utilizing an adaptive clamping structure, a center straightening device and wireless data transmission, the system ensures that the anchor bolt axis is aligned, reduces stress concentration, simplifies the operation process and improves data stability.
It enables efficient and accurate anchoring force detection in confined spaces, reduces the risk of anchor damage, improves the real-time performance and reliability of test data, simplifies the operation process, and reduces labor requirements.
Smart Images
Figure CN122385348A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of anchor bolt anchoring force testing technology. It relates to a pipe joint anchor bolt anchoring force testing system and method suitable for quality inspection of support in underground engineering projects such as mine roadways and tunnels. Background Technology
[0002] As a core component in the support system of underground engineering such as mine roadways and tunnels, the anchoring force of pipe-jointed anchors directly determines the safety and stability of the support structure. During actual on-site construction and subsequent operation and maintenance, the anchoring force of the anchored pipe-jointed anchors needs to be tested to assess whether the support quality meets the design requirements.
[0003] Existing pipe-joint anchor bolt anchoring force testing devices have several technical defects: First, the clamping components only contact the anchor bolt ring at a few points. This small contact area easily leads to localized stress concentration, causing deformation and damage to the anchor bolt retaining ring, rendering it unusable. It also results in uneven force transmission, distorting test data and failing to accurately reflect the actual anchoring force. Second, accurate testing requires the tension axis to coincide with the anchor bolt axis. Existing pipe-joint anchor bolt anchoring force testing devices struggle to meet this requirement, often requiring repeated adjustments or complex structures for adjustment. If the tension axis does not coincide with the anchor bolt axis, adjusting the relative position of the anchor bolt and the tensioning device further reduces the contact area, or even prevents proper contact. Third, as part of existing technology, the testing device has a complex structure and numerous components, resulting in a large size and heavy weight. This makes rapid deployment in confined working spaces such as mine roadways and tunnels inconvenient, and the operation process is cumbersome, requiring highly skilled operators. Furthermore, operators working under the anchor bolt pose safety hazards. Fourth, existing devices mostly use manual presses to power the pressure cylinders. This method results in large fluctuations in test data, making it unstable. Moreover, displacement measurement sensors mostly use cable-based sensors, which pose a risk of being pulled or damaged. The real-time performance and consistency of tension and displacement data are poor, leading to low test reliability and efficiency. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide an intelligent pipe joint anchor bolt anchoring force testing system and testing method. First, the system has a simple structure, is portable and efficient, provides accurate testing, has low damage and strong versatility. Second, it can simplify on-site wiring and achieve lightweight operation, so as to facilitate application in narrow working spaces such as mine roadways and tunnels.
[0005] The technical solution of the present invention is as follows: An intelligent pipe joint anchor bolt anchoring force testing system includes an end-pulling mechanism used in conjunction with an anchor bolt pull-out instrument, and further includes a compressed air source, an oil tank, a gas-liquid booster pump, and a hollow jack. The exposed end of the pipe joint anchor bolt is fixedly connected to an anchor bolt ring. The end-pulling mechanism includes a cylindrical fixing sleeve with a left end plate and a right end plate fixedly attached. The left end plate has a central hole, and the right end plate is fixedly connected to a traction rod. A first arc-shaped notch communicating with the left end plate is opened on the left side of the fixing sleeve, and a second arc-shaped notch communicating with the first arc-shaped notch is opened on the right side of the first arc-shaped notch. A flat, fixed step is installed inside the fixing sleeve. The left side of the fixed step is fixedly attached to the left end plate and has a center located on one side of the first arc-shaped notch. The arc-shaped end face is flush with the wall of the central hole; a movable step is placed inside the fixed sleeve; the movable step has an arc-shaped wall surface for fitting onto the outer wall of the pipe joint anchor and a fitting notch, the arc-shaped wall surface and the arc-shaped end face of the fixed step can be aligned to form a complete circle on the outer wall of the pipe joint anchor; a compressed air source is connected to the pneumatic drive end of a gas-liquid booster pump through a high-pressure air pipe, the oil inlet of the gas-liquid booster pump is connected to an oil tank through a pipeline, and the oil outlet is connected to a reversing valve, the reversing valve is connected to a hollow jack through an oil inlet pipe and an oil drain pipe; a traction rod passes through the central hole of the hollow jack; a baffle is fixedly installed on one side of the hollow jack, and a laser displacement sensor is installed on one side of the traction rod, with its position directly opposite the baffle.
[0006] Preferably, the high-pressure air pipe is equipped with an air pressure reducing valve.
[0007] More preferably, a pressure gauge for real-time monitoring of the driving air pressure is also connected between the air pressure reducing valve and the gas-liquid booster pump.
[0008] Preferably, a positioning locking ring is installed at the outer end of the hollow jack.
[0009] Preferably, the testing system further includes a support sleeve that covers the fixing sleeve inside, with one end of the support sleeve resting against the rock wall and the other end resting against the inner end of the hollow jack.
[0010] Preferably, the testing system further includes a centering mechanism; the centering mechanism includes an anchor bolt expansion mechanism; the anchor bolt expansion mechanism includes an expansion cylinder with slits on its sidewalls, a threaded hole at the axial position of the expansion cylinder, and an expansion head disposed in the threaded hole; the expansion head includes a screw section that mates with the threaded hole and a conical section located outside the screw section and integrally formed with the screw section, the small end of the conical section being connected to the screw section, the large end being external, and an external wrench hole being provided at this end; an internal wrench hole is provided at the front end of the expansion cylinder.
[0011] More preferably, the central straightening mechanism further includes a diameter-maintaining ring; the diameter-maintaining ring is located radially outward from the position of the expansion cylinder.
[0012] More preferably, a positioning locking ring is installed at the outer end of the hollow jack; the testing system also includes a support sleeve that covers the fixing sleeve inside, one end of which rests against the rock wall and the other end against the inner end of the hollow jack; the testing system also includes a central straightening mechanism; the central straightening mechanism includes an anchor bolt expansion mechanism; the anchor bolt expansion mechanism includes an expansion cylinder with slits on its sidewalls, a threaded hole at the axial position of the expansion cylinder, and an expansion head disposed in the threaded hole; the expansion head includes a screw section that mates with the threaded hole and a conical section located outside the screw section and integrally formed with the screw section, the small end of the conical section connecting to the screw section and the large end facing outwards; the central straightening mechanism also includes a gauge retaining ring; the gauge retaining ring is located radially outwards from the position of the expansion cylinder.
[0013] A method for testing the anchoring force of intelligent pipe-joint anchors, based on the aforementioned intelligent pipe-joint anchoring force testing system, comprises the following steps: Step 1: After inserting the expansion head into the expansion cylinder, screw it into the center hole of the exposed end of the pipe joint anchor rod; rotate the expansion head to move it axially and expand the expansion cylinder radially until the expansion cylinder is tightly fitted with the inner wall of the pipe joint anchor rod, and then install the gauge ring; Step 2: Install the end pull-out mechanism of the anchoring force testing device, so that the movable step of the end pull-out mechanism rests against the side of the fixed step, and the sleeve notch faces the side where the first arc-shaped notch is located; align the second arc-shaped notch with the side of the anchor ring, and align the first arc-shaped notch with the side of the pipe seam anchor rod inside the anchor ring; move the fixed sleeve radially to fit the anchor ring and the pipe seam anchor rod into it, and make the arc-shaped step surface of the fixed step fit against the left side of the anchor ring; Step 3: Pull and rotate the fixed sleeve until the relative rotation angle between the fixed sleeve and the movable step reaches 180°; continue to pull the fixed sleeve so that the arc-shaped wall of the movable step and the arc-shaped end face of the fixed step are joined and attached to the outer wall of the pipe joint anchor rod; in this state, one side of both the movable step and the fixed step is flush with the inner side of the left end plate, and the right side is attached to the side of the anchor rod ring 360°. Step 4: Install the support sleeve, hollow jack, positioning locking ring, baffle, and laser displacement sensor in sequence; Step 5: Open the valve of the compressed air source, adjust the air pressure reducing valve to drive air pressure of 0.5~0.8 MPa, start the gas-liquid booster pump, operate the reversing valve to supply oil to the hollow jack, apply a preload of 5%~10% of the estimated maximum pull-out force to the pipe seam anchor rod, continue for 5~10 minutes, and check whether each part of the device is working properly and whether the data acquisition system is stable. Step 6: Record the initial position of the pipe joint anchor bolt. Use a graded loading method, with each loading amount being 10%~15% of the estimated maximum pull-out force. After each loading, maintain the load stable for 2~3 minutes, and record the corresponding anchor bolt displacement data. When the anchor bolt shows plastic deformation, the anchor bolt body slides uniformly out of the hole, the pull-out force reaches the preset test load, or the anchor bolt falls off, stop loading. This completes one test. The system collects and stores in real time the displacement data of the pipe joint anchor recorded by the laser displacement sensor, as well as the real-time tension data output by the anchor pull-out instrument. This data is wirelessly transmitted to a portable data acquisition terminal, which automatically generates a tension-displacement curve. After exporting the tension-displacement data, the ultimate anchoring force or working anchoring force of the anchor is determined based on the curve characteristics, thereby evaluating the anchoring performance of the anchor.
[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an intelligent pipe joint anchor bolt anchoring force testing system and method. The adaptive clamping structure of "fixed step + movable step" reduces stress concentration; the central straightening device ensures that the force axis coincides with the anchor bolt axis, reducing testing errors and anchor bolt damage; wireless transmission avoids the risks of cable entanglement, pulling, and damage in complex downhole environments; the lightweight design makes the entire tensile device more portable, especially suitable for operation in confined spaces; high-precision synchronous acquisition ensures the real-time and consistency of tensile force and displacement data, significantly improving testing reliability and efficiency; the gas-liquid pressurization system ensures data stability and accuracy, reduces manual operation, and lowers labor costs. Details are as follows: (1) The end pull-out mechanism in the system adopts an adaptive clamping structure of "fixed step + movable step". The movable step can adjust the angle in real time according to the small displacement of the anchor rod during the pull-out process, so that the anchor rod is subjected to uniform force in the circumference, completely avoids local stress concentration, effectively prevents deformation and damage of the anchor rod retaining ring, ensures the reusability of the anchor rod after testing, and reduces engineering costs.
[0015] (2) The end-pulling mechanism in the system has a simple overall structure, few parts, low manufacturing cost, and more convenient operation. The fixed sleeve adopts a radial notch design, which can be quickly put on and taken off. It is small in size and light in weight, making it easy to transport and deploy in narrow spaces such as mine roadways and tunnels. The operation process is simple and easy to understand, requiring no professional technicians. On-site construction personnel can complete the test after simple training.
[0016] (3) By replacing the movable steps of different specifications, it can be adapted to the anchoring force test of pipe joint anchors of various diameters (φ16mm~φ32mm), without the need to configure a separate test device for anchors of different specifications, thus expanding the applicability of the end pull-out mechanism.
[0017] (4) The optimized technical solution of the present invention adopts a central straightening mechanism, which can effectively suppress the radial shrinkage (diameter reduction) phenomenon of the pipe joint anchor rod when under tension, and ensure that the tensile stress is concentrated at the end of the anchor rod, significantly improve the axial stability of the anchor rod during the pull-out process, reduce the non-axial stress component, thereby improving the authenticity and accuracy of the test data and the reusability of the anchor rod.
[0018] (5) The system of this invention adopts a high-precision wireless displacement measurement system and a wireless hydraulic sensing and data acquisition system. The displacement measurement uses a high-precision laser displacement sensor to achieve non-contact, high-frequency, and wireless acquisition, and sends real-time displacement data to a remote data acquisition device. The accuracy is high, and no data cable needs to be laid, which greatly simplifies the on-site installation process. The tensile force measurement uses a hydraulic sensor with integrated wireless transmission function, which is directly installed in the hydraulic pipeline of the anchor bolt pull-out device. The sensor monitors the hydraulic pressure in real time and automatically converts it into axial tensile force value according to the effective area of the piston. The tensile force data is transmitted in real time to a portable intelligent data acquisition terminal (such as an explosion-proof tablet computer or a dedicated handheld device) via wireless signal. The terminal receives tensile force and displacement data synchronously, automatically plots the tensile force-displacement curve, and has peak hold, data storage, curve analysis, and report generation functions.
[0019] (6) The system of the present invention uses a gas-liquid booster system to replace manual operation of the press. The gas-liquid booster system ensures the stability and accuracy of the data, reduces the number of personnel involved, and reduces labor costs. Attached Figure Description
[0020] Figure 1 This is a three-dimensional structural schematic diagram of an embodiment of the end-pulling mechanism of the present invention, in which the movable step is omitted.
[0021] Figure 2 This is a cross-sectional structural schematic diagram of an embodiment of the end-pulling mechanism of the present invention, in which the movable step is omitted.
[0022] Figure 3 This is a schematic diagram of the shape of the movable step in an embodiment of the end-pulling mechanism of the present invention.
[0023] Figure 4 This is a schematic diagram of the usage state of an embodiment of the end-pulling mechanism of the present invention. Figure 1 .
[0024] Figure 5 This is the present invention. Figure 4 The diagram shows a cross-sectional view of the structure in its operational state.
[0025] Figure 6 This is a schematic diagram of the usage state of an embodiment of the end-pulling mechanism of the present invention. Figure 2 .
[0026] Figure 7 This is the present invention. Figure 6 The diagram shows a cross-sectional view of the structure in its operational state.
[0027] Figure 8 This is a schematic diagram of the overall structure of an embodiment of the pipe joint anchor bolt anchoring force testing system of the present invention.
[0028] Figure 9 This is a schematic diagram of an embodiment of the anchor bolt expansion mechanism of the present invention.
[0029] Figure 10 This is a schematic diagram of the diameter-maintaining ring and its installation position in an embodiment of the present invention.
[0030] Explanation of reference numerals in the attached drawings: 1. Traction rod; 2. Fixed sleeve; 3. Fixed step; 4. First arc-shaped notch; 5. Second arc-shaped notch; 6. Movable step; 7. Pipe seam anchor; 8. Anchor ring; 9. Compressed air source; 10. Air pressure reducing valve; 11. High-pressure air pipe; 12. Pressure gauge; 13. Oil tank; 14. Gas-liquid booster pump; 15. High-pressure oil pipe; 16. Reversing valve; 17. Oil inlet pipe; 18. Oil drain pipe; 19. Positioning locking ring; 20. Hollow jack; 201. Piston; 21. Baffle; 22. Laser displacement sensor; 23. Rock wall; 24. Support sleeve; 25. Expansion cylinder; 26. Expansion head; 27. External wrench hole; 28. Cut; 29. Internal wrench hole; 30. Gauge retaining ring. Detailed Implementation
[0031] The present invention will be further described below with reference to specific embodiments.
[0032] like Figure 8 The embodiment of the pipe-seam anchor bolt anchoring force testing system of the present invention includes an end pull-out mechanism. The end pull-out mechanism is used in conjunction with an anchor bolt pull-out instrument for testing the anchoring force of the pipe-seam anchor bolt. The outer end of the pipe-seam anchor bolt 7 involved in the present invention (i.e., the end exposed from the rock wall 23) is fixed with an anchor bolt ring 8 by welding.
[0033] Figures 1 to 7 The structure and operational status of the end-pull mechanism are shown. For example... Figure 1 and Figure 2 The end-pulling mechanism includes a fixed sleeve 2. As the main supporting component of the end-pulling mechanism, the fixed sleeve 2 is welded from high-strength steel plates, possessing sufficient structural strength to withstand the pull-out load. The fixed sleeve 2 is a cylindrical shape with a left end plate and a right end plate welded on. The left end plate is a circular plate with a central hole (i.e., an overall annular plate), the diameter of which is larger than the outer diameter of the anchor rod 7 to be tested but smaller than the outer diameter of the anchor ring 8. A traction rod 1 is fixedly connected to the center of the right end plate by welding. The traction rod 1 runs coaxially with the fixed sleeve 2 to ensure no offset during the transmission of pulling force.
[0034] The fixed sleeve 2 has a first arc-shaped notch 4 on its left side, which communicates with the left end plate and is used for the radial insertion of the pipe anchor 7. A second arc-shaped notch 5 on its right side, which communicates with the first arc-shaped notch 4 and is used for the radial insertion of the anchor ring 8. The circumferential dimension of the second arc-shaped notch 5 is larger than that of the first arc-shaped notch 4. The first arc-shaped notch 4 is formed by cutting the left end plate and the cylinder wall. The second arc-shaped notch 5 is formed by cutting the cylinder wall.
[0035] In use, the second arc-shaped notch 5 is aligned with the side of the anchor ring 8, and the first arc-shaped notch 4 is aligned with the side of the pipe seam anchor 7 inside the anchor ring 8. The radially moving fixing sleeve 2 is used to fit the anchor ring 8 and the pipe seam anchor 7 into it.
[0036] The traction rod 1 is made of high-strength alloy material, and its left end is welded to the right end plate of the fixing sleeve 2. A fixed step 3 is fixedly installed inside the fixing sleeve 2 by welding. This fixed step 3 is flat, with its left side adhered to (by welding) the left end plate, and has an arc-shaped end face whose center is located on one side of the first arc-shaped notch 4, and this arc-shaped end face is flush with the wall of the central hole. This fixed step 3 is used for the initial positioning and axial limiting of the anchor ring 8.
[0037] The fixed sleeve 2 contains a Figure 3 The movable step 6 is shown in the diagram. This movable step 6 is a flat plate with the same thickness as the fixed step 3, and has an arc-shaped wall surface for fitting onto the outer wall of the pipe anchor 7 and a fitting notch. The arc-shaped wall surface of the movable step 6 and the arc-shaped end face of the fixed step 3 can align to form a complete circle on the outer wall of the pipe anchor 7. The radial dimension of this complete circle is smaller than the outer diameter of the anchor ring 8. The circumferential dimension of the fitting notch is larger than the outer diameter of the pipe anchor 7 being tested.
[0038] like Figure 4 and Figure 5 Before the anchor ring 8 and the pipe joint anchor 7 are fitted into the fixed sleeve 2, the movable step 6 is positioned against the right side of the fixed step 3, with the fitting notch facing the side where the first arc-shaped notch 4 is located to avoid obstructing the radial movement of the fixed sleeve 2 as it fits the anchor ring 8 and the pipe joint anchor 7. After fitting, the movable step 6 is located between the fixed step 3 and the anchor ring 8.
[0039] Pull and rotate the fixed sleeve 2 to the right. Under the friction of the anchor ring 8, the movable step 6 cannot rotate synchronously with the fixed sleeve 2. There is relative rotation between the fixed sleeve 2 and the movable step 6 until the relative rotation angle between the fixed sleeve 2 and the movable step 6 reaches 180°. Continue to pull the fixed sleeve 2 to the right, so that the arc-shaped wall surface of the movable step 6 merges and adheres to the arc-shaped end face of the fixed step 3 onto the outer wall of the pipe joint anchor 7. Figure 6 and Figure 7 As shown. In this state, the left sides of both the movable step 6 and the fixed step 3 are flush with the inner side of the left end plate, and the right sides are 360° fitted to the left side of the anchor ring 8.
[0040] Among them, the movable step 6 is made of wear-resistant alloy material and can rotate freely 360 degrees around the axis of the pipe seam anchor rod 7.
[0041] Still Figure 8 The embodiment of the pipe joint anchor bolt anchoring force testing system of the present invention also includes a compressed air source 9, an oil tank 13, a gas-liquid booster pump 14, a pressure gauge 12, and a hollow jack 20 as power sources.
[0042] Compressed air source 9 is connected to the pneumatic drive end of the gas-liquid booster pump 14 via a high-pressure air pipe 11 equipped with an air pressure reducing valve 10. The oil inlet of the gas-liquid booster pump 14 is connected to the oil tank 13 via a pipeline, and the oil outlet is connected to a reversing valve 16 via a high-pressure oil pipe 15. The reversing valve 16 is connected to the oil inlet and oil outlet of the hollow jack 20 via an oil inlet pipe 17 and an oil drain pipe 18, respectively. The pressure gauge 12 is connected in parallel between the air pressure reducing valve 10 and the gas-liquid booster pump 14 for real-time monitoring of the driving air pressure.
[0043] The traction rod 1 passes through the central hole of the hollow jack 20. A baffle 21 is fixedly installed on one side of the hollow jack 20, and a laser displacement sensor 22 is installed on one side of the traction rod 1, positioned directly opposite the baffle 21, for monitoring the axial displacement of the pipe seam anchor 7 during the pulling process.
[0044] A positioning locking ring 19 is installed at the outer end of the hollow jack 20 (i.e. the end away from the anchor rod). The main function of the positioning locking ring 19 is to fix the position of the hollow jack 20 during the pull-out test, prevent it from axially shifting or rotating due to uneven force, ensure that the pull-out force is transmitted along the axis of the anchor rod, avoid test errors and equipment damage caused by eccentric loading, and improve the stability and safety of the test.
[0045] This embodiment further includes a support sleeve 24 that covers the fixed sleeve 2 inside. One end of the support sleeve 24 rests against the rock wall 23, and the other end rests against the inner end of the hollow jack 20, forming a stable support structure. When the gas-liquid booster pump 14 pushes the piston 201 of the hollow jack 20, the support sleeve 24 provides a reaction force to the hollow jack 20, ensuring that the piston 201 can stably drive the traction rod 1 to move outward, thereby applying tension to the pipe joint anchor 7.
[0046] During operation, compressed air from compressed air source 9 is regulated to a stable pressure by air pressure reducing valve 10, driving the piston of air-liquid booster pump 14 to reciprocate, boosting the low-pressure hydraulic oil in oil tank 13 to a high-pressure state. The high-pressure oil enters the cylinder chamber of hollow jack 20 through reversing valve 16, pushing the jack piston outward, which in turn drives traction rod 1 and fixed sleeve 2 to apply axial tension to the anchor rod. An anchor rod pull-out instrument, serving as a shaft end force testing device, collects pull-out force data in real time. Laser displacement sensor 22 synchronously records the elongation of the pipe joint anchor rod 7. The anchoring performance and deformation characteristics of the pipe joint anchor rod 7 can be analyzed by the correspondence between pull-out force data and elongation. When the pipe joint anchor rod 7 undergoes plastic deformation, the pipe joint anchor rod 7 slides uniformly out of the hole, the pull-out force reaches the preset test load, or the anchor rod falls off, loading is stopped, and reversing valve 16 is switched to allow the high-pressure oil to flow back to oil tank 13, completing the unloading.
[0047] Furthermore, to effectively suppress the radial shrinkage (diameter reduction) phenomenon of the pipe-joint anchor 7 under tension and to ensure that the tensile stress is concentrated at the outer end of the pipe-joint anchor 7, this system is equipped with a central straightening mechanism. The central straightening mechanism includes... Figure 9 The anchor bolt expansion mechanism shown and Figure 10 The diameter retaining ring 30 is shown.
[0048] like Figure 9 The anchor bolt expansion mechanism includes an expansion cylinder 25 with a slit 28 on its sidewall. A threaded hole is located at the axial center of the expansion cylinder 25, and an expansion head 26 is disposed within this threaded hole. The expansion head 26 includes a screw section that mates with the threaded hole and a conical section located outside the screw section and integrally formed with it. The smaller end of the conical section connects to the screw section, while the larger end is external and has an external wrench hole 27. An internal wrench hole 29 is located at the front end of the expansion cylinder 25 (i.e., the end used to penetrate into the slotted anchor bolt 7). The slit 28 is used to generate a uniform radial expansion force during the expansion process.
[0049] The expansion cylinder 25 is generally made of high-strength alloy steel. When the cone section has not entered, its outer diameter is slightly smaller than the inner diameter of the pipe joint anchor rod 7, and it can be freely inserted into the center hole of the pipe joint anchor rod 7.
[0050] After the front end of the expansion cylinder 25 is inserted into the pipe seam anchor 7, an L-shaped hex wrench is inserted into the inner wrench hole 29 and another hex wrench is inserted into the outer wrench hole 27 by means of the pipe seam of the pipe seam anchor 7. The expansion head 26 is rotated. With the threaded hole and the screw section cooperating, the expansion head 26 moves axially and gradually enters the expansion cylinder 25. During this process, the pipe seam anchor 7 is gradually expanded by the expansion cylinder 25, so that the expansion cylinder 25 and the inner wall of the pipe seam anchor 7 are tightly fitted.
[0051] like Figure 10The retaining ring 30 is fitted around the axially outer side of the exposed rock face 23 portion of the pipe-joint anchor 7 and radially outer side of the expansion cylinder 25. The function of the retaining ring 30 is to limit the lateral (radial) deformation of the pipe-joint anchor 7, maintain the roundness of the anchor 7 under tension, and prevent local deformation from affecting test accuracy. When pull-out force is applied to the pipe-joint anchor 7, the radial support force of the expansion cylinder 25 and the constraint effect of the retaining ring 30 together maintain the roundness of the anchor 7, ensuring that the pull-out force is evenly transmitted to the anchoring section, thereby obtaining accurate anchoring performance data.
[0052] The following example illustrates the testing method of the pipe joint anchor bolt anchoring force testing system of the present invention.
[0053] Step 1: Insert the expansion head 26 into the expansion cylinder 25, ensuring the cut 28 is free and unobstructed. Screw the expansion cylinder 25 into the center hole of the exposed end of the pipe anchor 7. Using the pipe seam of the pipe anchor 7, insert an L-shaped hex wrench into the inner wrench hole 29 and another hex wrench into the outer wrench hole 27, and rotate the expansion head 26 to move it axially and expand the expansion cylinder 25 radially until the expansion cylinder 25 is tightly fitted against the inner wall of the pipe anchor 7. Then tighten the retaining ring 30.
[0054] Step 2: Install the end pull-out mechanism of the anchoring force testing device, ensuring that the movable step 6 of the end pull-out mechanism rests against the side of the fixed step 3, with the sleeve notch facing the side where the first arc-shaped notch 4 is located. Move the end pull-out mechanism to the side of the pipe joint anchor 7 to be tested, aligning the second arc-shaped notch 5 with the side of the anchor ring 8, and aligning the first arc-shaped notch 4 with the pipe joint anchor 7 portion inside the anchor ring 8. Radially move the fixed sleeve 2 to fit the anchor ring 8 and the pipe joint anchor 7 into it, ensuring that the arc-shaped step surface of the fixed step 3 fits against the left side of the anchor ring 8. After fitting, the movable step 6 is positioned between the fixed step 3 and the anchor ring 8. Initial positioning is complete.
[0055] Step 3: Pull and rotate the fixed sleeve 2 until the relative rotation angle between the fixed sleeve 2 and the movable step 6 reaches 180°; continue pulling the fixed sleeve 2 so that the arc-shaped wall surface of the movable step 6 and the arc-shaped end face of the fixed step 3 are joined and attached to the outer wall of the pipe joint anchor rod 7; in this state, one side of both the movable step 6 and the fixed step 3 is flush with the inner side of the left end plate, and the right side is attached to the side of the anchor rod ring 8 at 360°. At this time, the anchor rod ring 8 is subjected to uniform circumferential force.
[0056] Step 4: Install the support sleeve 24, hollow jack 20, positioning locking ring 19, baffle 21, and laser displacement sensor 22 in sequence. Ensure that the center axes of the expansion cylinder 25, pipe seam anchor 7, support sleeve 24, hollow jack 20, and traction rod 1 are aligned to avoid eccentric loading. Check that all pipe connections are secure and leak-free.
[0057] Step 5: Open the valve of the compressed air source 9, adjust the air pressure reducing valve 10 to the driving air pressure (usually 0.5~0.8 MPa), start the gas-liquid booster pump 14, slowly operate the reversing valve 16 to supply oil to the hollow jack 20, apply a preload of 5%~10% of the estimated maximum pull-out force to the pipe seam anchor rod 7, continue for 5~10 minutes, and check whether each part of the device is working properly and whether the data acquisition system is stable.
[0058] Step 6: Record the initial position of the pipe joint anchor 7. Use a graded loading method, with each stage loading at 10%~15% of the estimated maximum pull-out force. After each stage of loading, maintain the load stable for 2~3 minutes, and record the corresponding anchor displacement data. Stop loading when the anchor exhibits plastic deformation, the anchor body slides uniformly out of the hole, the pull-out force reaches the preset test load, or the anchor falls off. This completes one test.
[0059] Step 7: The system collects and stores in real time the displacement data of the pipe-seam anchor 7 recorded by the laser displacement sensor 22, as well as the real-time tension data output by the anchor pull-out device. This data is wirelessly transmitted to a portable data acquisition terminal, which automatically generates a tension-displacement curve. After exporting the tension-displacement data, the ultimate anchoring force (i.e., the force value corresponding to the peak tension) or working anchoring force (the force value corresponding to the preset allowable displacement) of the anchor can be determined based on the curve characteristics, thereby evaluating the anchoring performance of the anchor.
[0060] Step 8: After the test, operate the reversing valve 16 to return the high-pressure oil to the oil tank 13, slowly unload to zero, and close the valve of the compressed air source 9 and the gas-liquid booster pump 14. Remove the positioning locking ring 19, hollow jack 20, support sleeve 24, fixing sleeve 2, and other components. Rotate the expansion head 26 in the opposite direction to contract the expansion cylinder 25. Remove the retaining ring 30 and the expansion cylinder 25 to complete a complete anchoring force test procedure.
Claims
1. An intelligent pipe joint anchor bolt anchoring force testing system, comprising an end-pulling mechanism used in conjunction with an anchor bolt pull-out instrument, and further comprising a compressed air source (9), an oil tank (13), a gas-liquid booster pump (14), and a hollow jack (20), wherein the exposed end of the pipe joint anchor bolt (7) is fixedly connected to an anchor bolt ring (8), characterized in that: The end-pulling mechanism includes a cylindrical fixed sleeve (2) with a left end plate and a right end plate fixedly attached. The left end plate has a central hole, and the right end plate is fixedly connected to a traction rod (1). The fixed sleeve (2) has a first arc-shaped notch (4) on the left side that communicates with the left end plate, and a second arc-shaped notch (5) on the right side that communicates with the first arc-shaped notch (4). A flat fixed step (3) is installed inside the fixed sleeve (2). The left side of the fixed step (3) is attached to the left end plate and has an arc-shaped end face with its center located on one side of the first arc-shaped notch (4). The arc-shaped end face is flush with the wall of the central hole. A movable step (6) is placed inside the fixed sleeve (2). The movable step (6) has a design for fitting around the outside of the pipe joint anchor rod (7). The arc-shaped wall surface and the socket notch of the wall, the arc-shaped wall surface and the arc-shaped end face of the fixed step (3) can be aligned to form a complete circle on the outer wall of the pipe seam anchor rod (7); the compressed air source (9) is connected to the pneumatic drive end of the gas-liquid booster pump (14) through the high-pressure air pipe (11), the oil inlet of the gas-liquid booster pump (14) is connected to the oil tank (13) through the pipeline, and the oil outlet is connected to the reversing valve (16), the reversing valve (16) is connected to the hollow jack (20) through the oil inlet pipe (17) and the oil drain pipe (18); the traction rod (1) passes through the center hole of the hollow jack (20); a baffle (21) is fixedly installed on one side of the hollow jack (20), and a laser displacement sensor (22) is installed on one side of the traction rod (1) with its position facing the baffle (21).
2. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 1, characterized in that: The high-pressure air pipe (11) is equipped with an air pressure reducing valve (10).
3. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 2, characterized in that: A pressure gauge (12) for real-time monitoring of the driving air pressure is also connected between the air pressure reducing valve (10) and the gas-liquid booster pump (14).
4. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 1, characterized in that: A positioning locking ring (19) is installed at the outer end of the hollow jack (20).
5. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 1, characterized in that: The testing system also includes a support sleeve (24) that covers the fixed sleeve (2) inside, with one end of the support sleeve (24) resting against the rock wall (23) and the other end resting against the inner end of the hollow jack (20).
6. The intelligent pipe joint anchor bolt anchoring force testing system as described in any one of claims 1 to 5, characterized in that: The testing system also includes a central straightening mechanism; the central straightening mechanism includes an anchor bolt expansion mechanism; the anchor bolt expansion mechanism includes an expansion cylinder (25) with a slit (28) on its side wall, and a threaded hole is provided at the axial position of the expansion cylinder (25), and an expansion head (26) is provided in the threaded hole; the expansion head (26) includes a screw section that mates with the threaded hole and a conical section located outside the screw section and integrally formed with the screw section, the small end of the conical section is connected to the screw section, the large end is outside, and an external wrench hole (27) is provided at the end of the expansion cylinder (25); an internal wrench hole (29) is provided at the front end of the expansion cylinder (25).
7. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 6, characterized in that: The central straightening mechanism also includes a diameter retaining ring (30); the diameter retaining ring (30) is located radially outside the position of the expansion cylinder (25).
8. The intelligent pipe joint anchor bolt anchoring force testing system as described in claim 2, characterized in that: A positioning locking ring (19) is installed at the outer end of the hollow jack (20); the test system also includes a support sleeve (24) that covers the fixed sleeve (2) inside, one end of the support sleeve (24) rests on the rock wall (23), and the other end rests on the inner end of the hollow jack (20); the test system also includes a central straightening mechanism; the central straightening mechanism includes an anchor bolt expansion mechanism; the anchor bolt expansion mechanism includes an expansion cylinder (25) with a slit (28) on its side wall, and a threaded hole is provided at the axial position of the expansion cylinder (25), and an expansion head (26) is provided in the threaded hole; the expansion head (26) includes a screw section that mates with the threaded hole and a conical section located outside the screw section and integrally formed with the screw section, the small end of the conical section is connected to the screw section, and the large end is outside; the central straightening mechanism also includes a gauge ring (30); the gauge ring (30) is located radially outside the position of the expansion cylinder (25).
9. A method for testing the anchoring force of an intelligent pipe-joint anchor, based on the intelligent pipe-joint anchoring force testing system of claim 8, characterized in that... Follow these steps to test: Step 1: Insert the expansion head (26) into the expansion cylinder (25) and screw it into the center hole of the exposed end of the pipe joint anchor rod (7); rotate the expansion head (26) to move it axially and expand the expansion cylinder (25) radially until the expansion cylinder (25) is tightly fitted with the inner wall of the pipe joint anchor rod (7), and then install the gauge ring (30). Step 2: Install the end pull-out mechanism of the anchoring force testing device, so that the movable step (6) of the end pull-out mechanism rests against the side of the fixed step (3), and the sleeve notch faces the side where the first arc notch (4) is located; make the second arc notch (5) aligned with the side of the anchor ring (8), and the first arc notch (4) aligned with the side of the pipe seam anchor (7) inside the anchor ring (8); move the fixed sleeve (2) radially to fit the anchor ring (8) and the pipe seam anchor (7) into it, and make the arc step surface of the fixed step (3) fit against the left side of the anchor ring (8); Step 3: Pull and rotate the fixed sleeve (2) until the relative rotation angle between the fixed sleeve (2) and the movable step (6) reaches 180°; continue to pull the fixed sleeve (2) so that the arc-shaped wall of the movable step (6) and the arc-shaped end face of the fixed step (3) are joined and attached to the outer wall of the pipe joint anchor (7); in this state, one side of the movable step (6) and the fixed step (3) are flush with the inner side of the left end plate, and the right side is attached to the side of the anchor ring (8) 360°. Step 4: Install the support sleeve (24), hollow jack (20), positioning locking ring (19), baffle (21), and laser displacement sensor (22) in sequence. Step 5: Open the valve of the compressed air source (9), adjust the air pressure reducing valve (10) to drive air pressure of 0.5~0.8 MPa, start the gas-liquid booster pump (14), operate the reversing valve (16) to supply oil to the hollow jack (20), apply a preload of 5%~10% of the estimated maximum pull-out force to the pipe seam anchor rod (7) for 5~10 minutes, check whether each part of the device is working properly and whether the data acquisition system is stable; Step 6: Record the initial position of the pipe joint anchor (7). Use a graded loading method, with each loading amount being 10%~15% of the estimated maximum pull-out force. After each loading, maintain the load stable for 2~3 minutes and record the corresponding anchor displacement data. When the anchor shows plastic deformation, the anchor body slides uniformly out of the hole, the pull-out force reaches the preset test load, or the anchor falls off, stop loading and consider the test complete. The system collects and stores in real time the displacement data of the pipe joint anchor (7) recorded by the laser displacement sensor (22) and the real-time tension data output by the anchor pull-out instrument; these data are wirelessly transmitted to the portable data acquisition terminal to automatically generate the tension-displacement curve; after exporting the tension-displacement data, the ultimate anchoring force or working anchoring force of the anchor is determined according to the curve characteristics, and then the anchoring performance of the anchor is evaluated.