Anchor rod dynamic pull-out test device and method under triaxial confining pressure environment

Abstract

The invention discloses an anchor rod dynamic pull-out test device and method in a triaxial confining pressure environment, and relates to the technical field of simulation experiments, the anchor rod dynamic pull-out test device comprises a table I, a full-length bonding anchoring rock mass model and a table II, a reserved channel is formed in the top of the table II, a moving plate is arranged in the reserved channel, and the moving plate is connected with the table I; a first hydraulic cylinder is fixedly installed at the bottom of the moving plate, a confining pressure applying structure is arranged at the top of the moving plate, a model supporting structure is arranged at the bottom of the second table, and a linkage frame is arranged at the top of the first table. The situation that the prefabricated anchor rod is subjected to multiple different instantaneous impact forces is avoided; and after a certain dynamic loading force drawing experiment is finished, the computer firstly controls the hydraulic cylinder III to contract, and the positioning plate applies a certain static loading force to the drawing steel plate, so that the stress condition of the anchor rod in a real roadway can be accurately simulated, and the accuracy of an experiment result is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of simulation experiments, and in particular to a dynamic pull-out test device and method for an anchor rod under a triaxial confining pressure environment. Background Art

[0002] Anchor support for coal mine tunnels is one of the key technologies to ensure safe mining of coal mines. As the mining depth of coal mines increases, the number of times the tunnels are affected by impact ground pressure gradually increases, seriously threatening the stability of the tunnel support.

[0003] Currently, research on the mechanical properties of anchor bolts is still mainly focused on exploring their internal bonding mechanism and load transfer characteristics under static load pullout behavior. This is different from the complex mechanical environment of static-dynamic load interaction and coupling acting on the support system in actual deep engineering. Summary of the Invention

[0004] The object of the present invention is to provide a dynamic pull-out test device and method for an anchor rod under a triaxial confining pressure environment, so as to solve the problems raised in the prior art.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a dynamic pulling test device for anchor rods under a triaxial confining pressure environment, comprising a table 1, a full-length bonded anchored rock model and a table 2, a reserved channel being provided on the top of the table 2, a moving plate being provided in the reserved channel, a hydraulic cylinder 1 being fixedly installed on the bottom of the moving plate, a confining pressure applying structure being provided on the top of the moving plate, a model supporting structure being provided on the bottom of the table 2, a linkage frame being provided on the top of the table 1, a drawing steel plate being fixedly installed inside the linkage frame, a positioning structure being installed on the drawing steel plate, the positioning structure cooperating with the confining pressure applying structure to fix the full-length bonded anchored rock model, the positioning structure cooperating with the confining pressure applying structure to establish a transmission relationship between the full-length bonded anchored rock model and the linkage frame, and a power loading structure being provided on the side of the top of the table 2 away from the drawing steel plate.

[0006] Preferably, a computer, an infrared speedometer and two high-speed cameras are provided on the top of table one, and a mounting frame one is fixedly installed between the infrared speedometer and the two high-speed cameras and table one. Two resistance strain gauges are provided on the top of table two, and multiple mounting frames three are fixedly installed on both sides of the top of table two. Rollers are rotatably installed on the outer side of the mounting frame three, and the multiple rollers are all arranged at the bottom of the linkage frame.

[0007] Preferably, the model support structure includes two sliding frames, guide rails are provided on the outside of the two sliding frames, three vertical rods are fixedly installed on the top of the two sliding frames, an arc-shaped support frame is fixedly installed on the top of the vertical rods, a short shaft is fixedly installed inside the arc-shaped support frame, a pneumatic cylinder is fixedly installed inside the guide rails, and the piston end of the pneumatic cylinder is fixedly connected to the sliding frame.

[0008] Preferably, a telescopic rod 1 is fixedly installed on both sides of the bottom of the moving plate, the hydraulic cylinder 1 and the telescopic rod 1 are both arranged between two guide rails, a plurality of square slots 2 are opened on one side of the moving plate, a plurality of square slots 1 are opened on one side of the table 2, electric push rods are fixedly embedded on both sides of the table 2, and a plug-in bracket is fixedly installed on the piston end of the electric push rod.

[0009] Preferably, the full-length bonded anchored rock model includes a prefabricated anchor rod and a casting model fixedly mounted on the outside of the prefabricated anchor rod, a positioning rod is fixedly installed on one end of the casting model away from the prefabricated anchor rod, a circular hole 1 is provided on the outside of the prefabricated anchor rod and the outside of the positioning rod, and an arc-shaped groove 2 is provided on one side of the prefabricated anchor rod.

[0010] Preferably, the confining pressure applying structure includes three double-axis hydraulic cylinders fixedly installed on the top of the moving plate and a hydraulic cylinder three arranged on one side of the drawn steel plate, both piston ends of the double-axis hydraulic cylinders are fixedly installed with fixed vertical plates, and the top of the fixed vertical plates is fixedly installed with a clamping frame, and both sides of the double-axis hydraulic cylinders are provided with telescopic rods two, and the two piston ends of the telescopic rods two are fixedly connected to the front fixed vertical plate, and the outer shell of the telescopic rods two is fixedly connected to the rear fixed vertical plate.

[0011] Preferably, a positioning plate is fixedly installed on the piston end of the third hydraulic cylinder, a mounting frame four is fixedly installed on the outer side of the third hydraulic cylinder, a plurality of fixed bent plates are fixedly installed between the mounting frame four and the table two, a guide shaft is slidably inserted on the mounting frame four, one end of the guide shaft is fixedly connected to the positioning plate, an empty groove is provided at the bottom of the positioning plate, an electromagnet is fixedly embedded on the side of the positioning plate close to the mounting frame four, and an arc-shaped groove one is provided on the side of the linkage frame close to the mounting frame four.

[0012] Preferably, the positioning structure includes a hydraulic cylinder 2 fixedly mounted on the drawn steel plate, a U-shaped frame fixedly mounted on the piston end of the hydraulic cylinder 2, and a plug-in shaft fixedly mounted on the U-shaped frame. A circular hole 3 and two circular holes 2 are provided on the top of the drawn steel plate. Both ends of the U-shaped frame extend to the inside of the two circular holes 2 respectively. The hydraulic cylinder 2 is arranged inside one of the circular holes 2 and fixedly connected to the drawn steel plate. The bottom end of the plug-in shaft passes through the circular hole 3.

[0013] Preferably, the power loading structure includes a high-pressure pump fixedly installed at the bottom of table two, a one-way valve fixedly installed at the air outlet end of the high-pressure pump, a pressure box fixedly connected to one end of the one-way valve, a solenoid valve fixedly connected to one side of the pressure box, a connecting pipe fixedly connected to one end of the solenoid valve, and an ejection frame fixedly connected to one end of the connecting pipe, an injection rod is inserted into the ejection frame, a plurality of mounting frames are fixedly installed between the outside of the ejection frame and table two, the pressure box is fixedly penetrated on table two, and an air pressure sensor is fixedly installed on the outside of the pressure box.

[0014] A dynamic pull-out test method for an anchor rod comprises the following steps: Step 1: Install three full-length bonded anchor rock models onto the model support structure, and control the two pneumatic cylinders to work for the first time, so that the front-most full-length bonded anchor rock model moves to the bottom of the reserved channel; Step 2: Hydraulic cylinder 1 is controlled to operate, and the six clamping frames are distributed to the front and rear sides of the front-most full-length bonded anchored rock model. Then, the three biaxial hydraulic cylinders are operated to retract, and the six clamping frames move to the outside of the casting model. Then, the computer controls hydraulic cylinder 1 to continue to extend, and the full-length bonded anchored rock model moves up to the top of table 2, and the moving plate moves up to the inside of the reserved channel. Step 3: Control the two electric push rods to work and retract, completing the transmission relationship between the motion plate and table 2; Step 4: The electromagnet works and is fixed to the drawing steel plate by magnetic force, controlling the extension of hydraulic cylinder 3. After a period of time, when the circular hole 3 opened in the drawing steel plate is aligned with the circular hole 1 opened in the prefabricated anchor rod, the electromagnet stops working, and the positioning plate finally presses against the casting model; hydraulic cylinder 2 works and contracts, driving the U-shaped frame downward, and the plug-in shaft passes through the circular hole 3 and the circular hole 1 opened in the prefabricated anchor rod; Step 5: Glue and fix two resistance strain gauges to the outer ends of the prefabricated anchor rod and the outer side of the end of the injection rod located outside the ejection frame, and set the required air pressure value inside the pressure box on the computer; Step 6: The computer controls the power loading structure to work according to the preset program. The high-pressure gas ejects the incident rod, and one end of the incident rod hits the linkage frame. Step 7: Repeat step 6 multiple times. After a step 6 is completed, the computer first controls the hydraulic cylinder 3 to contract, and the positioning plate applies a certain static load to the drawn steel plate; Step 8: Remove the resistance strain gauge; control the hydraulic cylinder 2 to extend, and the plug-in shaft leaves the inside of the circular hole 1; then control the hydraulic cylinder 3 to work and retract, control the electromagnet to work, the positioning plate drives the electromagnet to move toward the drawing steel plate, the electromagnet drives the drawing steel plate to move synchronously, and the linkage frame moves synchronously; Step 9: Control the electric push rod to extend, the plug-in frame is separated from the contact with the moving plate, control the hydraulic cylinder to work and retract, and the moving plate moves down; the double-axis hydraulic cylinder works and extends, the clamping frame is separated from the casting model, and the hydraulic cylinder continues to work to drive the moving plate to move down.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This application conducts multiple dynamic load pulling experiments. According to the preset program, the air pressure value inside the pressure box is different each time the pressure box is released, and different sizes of dynamic loads are applied to the prefabricated anchor rods to simulate the situation where the casting model is subject to three-dimensional stress limitation and the prefabricated anchor rods are subjected to multiple different instantaneous impact forces; and after a dynamic load pulling experiment is completed, the computer first controls the hydraulic cylinder to contract three times, and the positioning plate applies a certain static load to the pulling steel plate. After a period of time, the hydraulic cylinder extends three times, and the positioning plate continues to limit the simulated casting model. Then the computer controls the anchor rod dynamic pulling test device to perform the next dynamic load pulling experiment; it can accurately simulate the stress conditions of the anchor rods in the real tunnel and ensure the accuracy of the experimental results.

[0016] 2. In this application, through the coordination of structures such as the moving plate, hydraulic cylinder, confining pressure application structure, linkage frame, pulling steel plate, and positioning structure, the staff only needs to place the full-length bonded anchored rock model on the model support structure. After that, the staff only needs to install the resistance strain gauge or adjust the position of the resistance strain gauge to complete the dynamic load pulling test of multiple full-length bonded anchored rock models. The experimental data can be collected easily and quickly from multiple full-length bonded anchored rock models to ensure the effect of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 This is a structural diagram of a mounting frame 1 of the present invention; Figure 3 This is a partial structural diagram of table 2 of the present invention; Figure 4 This is a structural diagram of table 2 of the present invention; Figure 5 It is a structural schematic diagram of the sports board of the present invention; Figure 6 It is a structural schematic diagram of the plug-in rack of the present invention; Figure 7 This is a schematic diagram of the matching structure of the plug-in rack and the motion board of the present invention; Figure 8 Schematic diagram of the structure of the mounting frame 4 of the present invention; Figure 9 It is a structural schematic diagram of the drawn steel plate of the present invention; Figure 10 Schematic diagram of the structure of the guide rail of the present invention; Figure 11 It is a structural schematic diagram of the vertical rod of the present invention; Figure 12 Schematic diagram of the structure of the arc support frame of the present invention.

[0018] Numbers in the figure: 1. Table 1; 2. Computer; 3. Mounting frame 1; 4. High-speed camera; 5. Infrared speedometer; 6. Table 2; 7. Pressure box; 8. Air pressure sensor; 9. One-way valve; 10. High-pressure pump; 11. Solenoid valve; 12. Connecting pipe; 13. Ejection frame; 14. Mounting frame 2; 15. Incident rod; 16. Resistance strain gauge; 17. Mounting frame 3; 18. Roller; 19. Linkage frame; 20. Drawing steel plate; 21. Reserved channel; 22. Moving plate; 23. Hydraulic cylinder 1; 24. Telescopic rod 1; 25. Double-axis hydraulic cylinder; 26. Fixed vertical plate; 27. Telescopic rod 2; 28. Clamp Frame; 29. ​​Casting model; 30. Precast anchor rod; 31. Round hole one; 32. Round hole two; 33. Round hole three; 34. U-shaped frame; 35. Plug-in shaft; 36. Hydraulic cylinder two; 37. Electromagnet; 38. Arc slot one; 39. Arc slot two; 40. Square slot one; 41. Plug-in frame; 42. Electric push rod; 43. Square slot two; 44. Fixed bent plate; 45. Mounting frame four; 46. Hydraulic cylinder three; 47. Positioning plate; 48. Empty slot; 49. Guide shaft; 50. Guide rail; 51. Sliding frame; 52. Vertical rod; 53. Arc support frame; 54. Short shaft; 55. Pneumatic cylinder; 56. Positioning rod. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] Example: Figures 1-12 As shown, the present invention provides a technical solution for an anchor dynamic pull-out test device under a triaxial confining pressure environment: Specifically, a computer 2, an infrared speedometer 5 and two high-speed cameras 4 are provided on the top of table 1. A mounting frame 3 is fixedly installed between the infrared speedometer 5 and the two high-speed cameras 4 and table 1. The high-speed camera 4 shoots video data, and the infrared speedometer 5 is used to detect speed data. Two resistance strain gauges 16 are provided on the top of table 2 6. One of the resistance strain gauges 16 is glued to the outside of one end of the incident rod 15 close to the linkage frame 19, and the other resistance strain gauge 16 is glued and fixed to the outside of one end of the prefabricated anchor rod 30 set on the outside of the casting model 29. The resistance strain gauge 16 is used to detect the deformation of the attached object. Multiple mounting frames 3 17 are fixedly installed on both sides of the top of table 2 6, and rollers 18 are rotatably installed on the outside of the mounting frames 3 17. Multiple rollers 18 are all arranged at the bottom of the linkage frame 19. The linkage frame 19 is supported by multiple rollers 18, so the friction force that the linkage frame 19 needs to overcome when moving is extremely small.

[0021] Specifically, the outer sides of the two sliding frames 51 in the model support structure are sleeved with guide rails 50, and the tops of the two sliding frames 51 are fixedly installed with three vertical rods 52. The three vertical rods 52 on the left and the three vertical rods 52 on the right correspond to each other to form three support frames. The arc-shaped support frame 53 fixedly installed on the top of the vertical rod 52 is fixedly installed with a short shaft 54 ​​inside. The full-length bonded anchor rock model includes a prefabricated anchor rod 30 and a casting model 29 fixedly sleeved on the outer side of the prefabricated anchor rod 30. A positioning rod 56 is fixedly installed on the end of the casting model 29 away from the prefabricated anchor rod 30. A circular hole 33 is opened on the outer side of the prefabricated anchor rod 30 and the outer side of the positioning rod 56. 1. After aligning the two circular holes 31 with the two short shafts 54 in a support frame, push the precast anchor rod 30 and the positioning rod 56 downward so that the precast anchor rod 30 moves and is supported by the two arc-shaped support frames 53. The two short shafts 54 pass through the two circular holes 31 so that the precast anchor rod 30 cannot rotate, completing the pre-installation of a full-length bonded anchor rock model. The other two full-length bonded anchor rock models can be installed in sequence. Due to the position setting of the circular holes 31 on the precast anchor rod 30 and the positioning rod 56, the precast anchor rod 30 can only be installed according to the preset state, so that the installed full-length bonded anchor rock model is in a ready-to-use state.

[0022] The number of vertical rods 52, arc-shaped support frames 53, and short shafts 54 can be set according to experimental needs.

[0023] A pneumatic cylinder 55 is fixedly installed inside the guide rail 50. The piston end of the pneumatic cylinder 55 is fixedly connected to the sliding frame 51. By controlling the two pneumatic cylinders 55 to work synchronously and the two sliding frames 51 to move synchronously, the positions of the three full-length bonded anchor rock models can be controlled.

[0024] Specifically, telescopic rods 24 are fixedly installed on both sides of the bottom of the moving plate 22, and the hydraulic cylinder 23 and the telescopic rod 24 cooperate to support the moving plate 22, so that the moving plate 22 can only move up and down. After the hydraulic cylinder 23 is controlled to work and drive the moving plate 22 to move down, since the hydraulic cylinder 23 and the telescopic rod 24 are both arranged between the two guide rails 50, the hydraulic cylinder 23 and the moving plate 22 will not affect the transportation of the full-length bonded anchored rock model; a plurality of square slots 43 are opened on one side of the moving plate 22, and a plurality of square slots 40 are opened on one side of the table 26. When the hydraulic cylinder 23 works to push the moving plate 22 After the moving plate 22 moves up and enters the reserved channel 21, the square slot 2 43 opened on the moving plate 22 will be aligned with the square slot 1 40 opened on the table 2 6; the two electric push rods 42 fixedly embedded on both sides of the table 2 6 are controlled to work and retract, so that the plug-in frame 41 fixedly installed on the piston end of the electric push rod 42 enters the square slot 2 43 from the inside of the square slot 1 40, and the two plug-in frames 41 are stuck between the moving plate 22 and the table 2 6, so that a firm transmission relationship is formed between the moving plate 22 and the table 2 6, so that the force applied to the moving plate 22 can only act on the table 2 6, thereby ensuring the service life of the hydraulic cylinder 1 23.

[0025] Specifically, the three dual-axis hydraulic cylinders 25 in the confining pressure applying structure are all fixedly installed on the top of the moving plate 22. The two piston ends of the dual-axis hydraulic cylinders 25 are fixedly installed with fixed vertical plates 26. The top of the fixed vertical plates 26 is fixedly installed with an arc-shaped clamping frame 28. The inner concave surfaces of the two clamping frames 28 are arranged opposite to each other, so by controlling the operation of the dual-axis hydraulic cylinders 25, the two clamping frames 28 can be controlled to approach or move away from each other, and the two clamping frames 28 can be controlled to clamp the full-length bonded anchor rock model, or leave from the outside of the full-length bonded anchor rock model.

[0026] Telescopic rods 27 are provided on both sides of the dual-axis hydraulic cylinder 25. The piston ends of the two telescopic rods 27 are fixedly connected to the front fixed vertical plate 26, and the outer shell of the telescopic rod 27 is fixedly connected to the rear fixed vertical plate 26. The setting of the telescopic rods 27 supports and limits the fixed vertical plate 26 to ensure the horizontal movement of the fixed vertical plate 26.

[0027] Specifically, a positioning plate 47 is fixedly installed on the piston end of hydraulic cylinder three 46, a mounting frame four 45 is fixedly installed on the outside of hydraulic cylinder three 46, and a plurality of fixed bent plates 44 are fixedly installed between mounting frame four 45 and table two 6. Therefore, hydraulic cylinder three 46 is fixedly installed on the top of table two 6 through fixed bent plates 44 and mounting frame four 45 to control the operation of hydraulic cylinder three 46 and the position of positioning plate 47. A guide shaft 49 is slidably inserted on mounting frame four 45, and one end of the guide shaft 49 is fixedly connected to the positioning plate 47. The guide shaft 49 limits the movement of the positioning plate 47 to ensure that the positioning plate 47 moves according to the preset trajectory.

[0028] A slot 48 is provided at the bottom of the positioning plate 47 , so that the movement of the positioning plate 47 will not contact the prefabricated anchor rod 30 and the resistance strain gauge 16 adhered to the outer side of the prefabricated anchor rod 30 .

[0029] An electromagnet 37 is fixedly embedded on the side of the positioning plate 47 close to the mounting frame four 45, an arc-shaped groove 2 39 is opened on one side of the prefabricated anchor rod 30, and an arc-shaped groove 1 38 is opened on the side of the linkage frame 19 close to the mounting frame four 45. The piston end of the hydraulic cylinder three 46 passes through the arc-shaped groove 1 38 and the arc-shaped groove 2 39 in sequence. The operation of the hydraulic cylinder three 46 will not be affected by the linkage frame 19 and the drawing steel plate 20.

[0030] Specifically, in the positioning structure, a U-shaped frame 34 is fixedly installed at the piston end of the second hydraulic cylinder 36, and a circular hole 33 and two circular holes 32 are opened on the top of the drawn steel plate 20. The two ends of the U-shaped frame 34 extend to the inside of the two circular holes 32 respectively. The U-shaped frame 34 moves synchronously with the drawn steel plate 20. The second hydraulic cylinder 36 is arranged inside one of the circular holes 32 and is fixedly connected to the drawn steel plate 20, and the bottom end of the plug-in shaft 35 fixedly installed on the U-shaped frame 34 passes through the circular hole 33.

[0031] Specifically, in the power loading structure, a high-pressure pump 10 is fixedly installed at the bottom of the table 2 6 , a one-way valve 9 fixedly installed at the outlet end of the high-pressure pump 10 is fixedly connected to the pressure box 7 at one end, a solenoid valve 11 fixedly connected to one side of the pressure box 7 is fixedly connected to a connecting pipe 12 at one end, an ejection frame 13 fixedly connected at one end of the connecting pipe 12 is inserted into the interior of which an injection rod 15 is provided, and a plurality of mounting frames 2 14 are fixedly installed between the outside of the ejection frame 13 and the table 2 6 , so that the ejection frame 13 cannot be moved, and an air pressure sensor 8 fixedly installed on the outside of the pressure box 7 is used to detect the air pressure value inside the pressure box 7; The high-pressure pump 10 is controlled to work, and the high-pressure pump 10 injects gas into the pressure box 7 through the one-way valve 9. Under the one-way conduction characteristic of the one-way valve 9, the gas inside the pressure box 7 cannot leave the pressure box 7 through the one-way valve 9; the air pressure sensor 8 detects the air pressure inside the pressure box 7, and the detection data of the air pressure sensor 8 is fed back to the computer 2 in real time. When the air pressure inside the pressure box 7 reaches a preset value, the computer 2 controls the high-pressure pump 10 to stop working and controls the solenoid valve 11 fixedly connected on one side of the pressure box 7 to work. The high-pressure gas inside the pressure box 7 is released into the ejection frame 13, ejecting the incident rod 15 inside the ejection frame 13, and controlling the operation of the power loading structure, that is, the gas with a preset pressure can eject the incident rod 15 to hit the linkage frame 19, and a resistance strain gauge 16 is pasted on the outside of the incident rod 15. The resistance strain gauge 16 detects the deformation data of the incident rod 15 when the incident rod 15 hits the linkage frame 19, which can realize the measurability and controllability of dynamic drawing energy.

[0032] In this application, the specific method of using the anchor bolt dynamic pulling test device composed of the table 1, table 2, 6, moving plate 22, hydraulic cylinder 1 23, confining pressure applying structure, model support structure, linkage frame 19, pulling steel plate 20, positioning structure, dynamic loading structure, etc. is as follows: Step 1: Computer 2 controls the retraction of two pneumatic cylinders 55 in the model support structure, completely lifting the carriage 51 off the bottom of table 2 6. The three full-length bonded anchor rock models are then mounted on the model support structure. Computer 2 controls the first operation of the two pneumatic cylinders 55, moving the frontmost full-length bonded anchor rock model to the bottom of the reserved channel 21.

[0033] Step 2: The computer 2 controls the hydraulic cylinder 1 23 to push the moving plate 22 upward. The upward movement of the moving plate 22 causes the six clamping frames 28 to move upward. Due to the position setting of the outer circular hole 1 31 of the prefabricated anchor rod 30, the outer circular hole 1 31 of the positioning rod 56 and the vertical rod 52, the casting model 29 is located at the preset position, so that the six clamping frames 28 are distributed to the front and rear sides of the full-length bonded anchored rock model at the front. Then the hydraulic cylinder 1 23 stops working, and the three double-axis hydraulic cylinders 25 work and contract, so that the six clamping frames 28 move synchronously, and finally the six clamping frames 28 move to the outside of the casting model 29 to clamp and fix the casting model 29; then the computer 2 controls the hydraulic cylinder 1 23 to continue to extend, and the full-length bonded anchored rock model clamped and fixed by the moving plate 22 and the six clamping frames 28 moves upward. The full-length bonded anchored rock model moves to the top of the table 2 6. After the moving plate 22 moves to the inside of the reserved channel 21, the hydraulic cylinder 1 23 completes this work.

[0034] Step 3: The two electric push rods 42 are controlled by the computer 2 to work and retract. The electric push rods 42 drive the plug-in frame 41 fixed at the piston end to move, so that the plug-in frame 41 is partially inserted into the square slot 2 43 opened on the motion plate 22, completing the transmission relationship between the motion plate 22 and the table 2 6.

[0035] Step 4: Control the electromagnet 37 embedded in the positioning plate 47 to work, and the working electromagnet 37 contacts the inside of the drawn steel plate 20. The electromagnet 37 is fixed to the drawn steel plate 20 by magnetic force; then control the hydraulic cylinder three 46 to work and extend, and the hydraulic cylinder three 46 pushes the positioning plate 47 to move. The positioning plate 47 drives the drawn steel plate 20 to move through the electromagnet 37, and the positioning plate 47 with the empty slot 48 can move to the outside of the prefabricated anchor rod 30. The drawn steel plate 20 moves and is sleeved to the outside of the prefabricated anchor rod 30. After a period of time, when the circular hole three 33 opened in the drawn steel plate 20 is aligned with the circular hole one 31 opened in the prefabricated anchor rod 30, the electromagnet 37 stops working, the linkage frame 19 loses the pull of the electromagnet 37, and the drawn steel plate The plate 20 and the prefabricated anchor rod 30 are in an interference fit state, so the relative position between the circular hole 33 and the circular hole 1 31 remains unchanged, and the final positioning plate 47 is against the casting model 29. At this time, the extension of the hydraulic cylinder 3 46 is hindered, and the internal hydraulic pressure of the hydraulic cylinder 3 46 increases. The computer 2 electrically connected to the hydraulic cylinder 3 46 monitors the internal hydraulic pressure changes of the hydraulic cylinder 3 46. When the internal hydraulic pressure of the hydraulic cylinder 3 46 reaches the preset value, the computer 2 controls the hydraulic cylinder 3 46 to suspend work, and the hydraulic cylinder 3 46 controls the positioning plate 47 to press against the casting model 29. The positioning plate 47 applies a preset axial pressure to the casting model 29; at this time, the full-length bonded anchor rock model is limited on the front, rear and axial sides, and the casting model 29 is subjected to triaxial pressure.

[0036] At this time, the drawn steel plate 20 is located on the shooting path of the left high-speed camera 4, the end of the linkage frame 19 close to the incident rod 15 is located on the shooting path of the right high-speed camera 4, and one end of the incident rod 15 is located on the measuring path of the infrared speed meter 5.

[0037] After the above-mentioned electromagnet 37 stops working, the hydraulic cylinder 2 36 fixedly inserted on the drawn steel plate 20 works and contracts, and the hydraulic cylinder 2 36 drives the U-shaped frame 34 to move downward. The plug-in shaft 35 passes through the circular hole 33 and the circular hole 1 31, and the U-shaped frame 34 and the plug-in shaft 35 are in contact with the drawn steel plate 20. When the hydraulic cylinder 2 36 is not working, the force of the left and right movement of the drawn steel plate 20 acts on the prefabricated anchor rod 30 through the U-shaped frame 34 and the plug-in shaft 35.

[0038] Step 5: After hydraulic cylinder three 46 stops working, the staff will glue and fix two resistance strain gauges 16 to the outside of the end of the prefabricated anchor rod 30 set on the outside of the casting model 29 and the outside of the end of the injection rod 15 located outside the ejection frame 13. After the resistance strain gauges 16 are fixed, the staff will set the required air pressure value inside the pressure box 7 on the computer 2 and then move away from table two 6.

[0039] Step 6: The computer 2 controls the power loading structure to work according to the preset program. When the air pressure value inside the pressure box 7 reaches the preset air pressure value, the computer 2 controls the electromagnetic valve 11 to open, and the high-pressure gas ejects the incident rod 15. One end of the incident rod 15 hits the linkage frame 19, so that the linkage frame 19 is subjected to the preset instantaneous impact force. The linkage frame 19 applies the instantaneous impact force to one end of the prefabricated anchor rod 30 through the drawn steel plate 20, the U-shaped frame 34 and the plug-in shaft 35, and the casting model 29 fixedly installed on the outside of the prefabricated anchor rod 30 is subjected to fixing forces in three directions. The high-speed camera 4 on the left side shoots the drawn steel plate 20 and the connection prefabricated fixed by the drawn steel plate 20. The motion data of the anchor rod 30 is captured by the high-speed camera 4 on the right side, and the motion data of the linkage frame 19 and the incident rod 15 are captured. The resistance strain gauge 16 on the outside of the precast anchor rod 30 and the resistance strain gauge 16 on the outside of the incident rod 15 detect the deformation data of the precast anchor rod 30 and the incident rod 15. The infrared velocimeter 5 measures the change data of the motion speed of the incident rod 15. The data detected by the two high-speed cameras 4, the infrared velocimeter 5 and the two resistance strain gauges 16 are transmitted to the computer 2 to complete the test data collection work when the precast anchor rod 30 is subjected to dynamic load pulling when the casting model 29 is subject to three-dimensional stress limitation, and a dynamic load pulling experiment is completed; the incident rod 15 is reset.

[0040] Step seven: Repeat step six multiple times, and conduct multiple dynamic load pulling experiments. Each time step six is ​​repeated, according to the preset program, the air pressure value inside the pressure box 7 is different each time the pressure box 7 is released, and different sizes of dynamic loads are applied to the prefabricated anchor rod 30 to simulate the situation where the casting model 29 is limited by three-dimensional stress and the prefabricated anchor rod 30 is subjected to multiple different instantaneous impact forces; and after a certain step six is ​​completed, the computer 2 first controls the hydraulic cylinder three 46 to contract, and the positioning plate 47 to apply a certain static load to the pulling steel plate 20. After a period of time, the hydraulic cylinder three 46 extends, and the positioning plate 47 continues to limit the simulated casting model 29, and then the computer 2 controls the anchor rod dynamic pulling test device to proceed to the next step six; it can accurately simulate the stress conditions of the anchor rods in the real tunnel and ensure the accuracy of the experimental results.

[0041] Step 8: Remove the resistance strain gauge 16; control the hydraulic cylinder 2 36 to extend. Since the casting model 29 and the prefabricated anchor rod 30 cannot move up and down, the plug-in shaft 35 can smoothly leave the inside of the circular hole 1 31; then control the hydraulic cylinder 3 46 to work and contract, control the electromagnet 37 to work, and the positioning plate 47 drives the electromagnet 37 to move toward the drawn steel plate 20. After the electromagnet 37 contacts the drawn steel plate 20, the electromagnet 37 drives the drawn steel plate 20 to move synchronously, and the linkage frame 19 moves synchronously.

[0042] Step nine: Control the electric push rod 42 to extend, so that the plug-in frame 41 is out of contact with the moving plate 22, control the hydraulic cylinder 1 23 to work and retract, and the moving plate 22 moves down. When the prefabricated anchor rod 30 moves into the two arc-shaped support frames 53, the hydraulic cylinder 1 23 stops working, the dual-axis hydraulic cylinder 25 works and extends, and the clamping frame 28 is separated from the casting model 29; then the hydraulic cylinder 1 23 continues to work to drive the moving plate 22 to move down, and finally the moving plate 22 is reset.

[0043] Step ten; control the two pneumatic cylinders 55 to work, so that the second full-length bonded anchored rock model moves to the top of the reserved channel 21; then sequentially perform the above steps two, three, three, four, five, six, and seven to experiment with the new full-length bonded anchored rock model.

[0044] In summary, this application cooperates with structures such as the moving plate 22, the hydraulic cylinder 23, the confining pressure application structure, the linkage frame 19, the drawing steel plate 20, and the positioning structure. The staff only needs to place the full-length bonded anchored rock model on the model support structure. After that, the staff only needs to install the resistance strain gauge 16 or adjust the position of the resistance strain gauge 16 to complete the dynamic load drawing test of multiple full-length bonded anchored rock models. The experimental data can be collected easily and quickly from multiple full-length bonded anchored rock models to ensure the effect of the experiment.

[0045] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. An anchor dynamic pullout test device under triaxial confining pressure environment, comprising table 1 (1), a full-length bonded anchor rock model and table 2 (6), characterized in that: A reserved channel (21) is provided on the top of the table 2 (6), a moving plate (22) is provided in the reserved channel (21), a hydraulic cylinder 1 (23) is fixedly installed on the bottom of the moving plate (22), a confining pressure applying structure is provided on the top of the moving plate (22), a model supporting structure is provided on the bottom of the table 2 (6), a linkage frame (19) is provided on the top of the table 1 (1), a drawing steel plate (20) is fixedly installed inside the linkage frame (19), a positioning structure is installed on the drawing steel plate (20), the positioning structure cooperates with the confining pressure applying structure to fix the full-length bonded anchored rock model, the positioning structure cooperates with the confining pressure applying structure to establish a transmission relationship between the full-length bonded anchored rock model and the linkage frame (19), and a power loading structure is provided on the side of the top of the table 2 (6) away from the drawing steel plate (20).

2. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: A computer (2), an infrared speedometer (5) and two high-speed cameras (4) are arranged on the top of the table one (1); a mounting frame one (3) is fixedly installed between the infrared speedometer (5) and the two high-speed cameras (4) and the table one (1); two resistance strain gauges (16) are arranged on the top of the table two (6); a plurality of mounting frames three (17) are fixedly installed on both sides of the top of the table two (6); rollers (18) are rotatably installed on the outer side of the mounting frame three (17); and the plurality of rollers (18) are arranged at the bottom of the linkage frame (19).

3. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: The model support structure comprises two sliding frames (51), the outer sides of the two sliding frames (51) are sleeved with guide rails (50), the tops of the two sliding frames (51) are fixedly mounted with three vertical rods (52), the tops of the vertical rods (52) are fixedly mounted with arc-shaped support frames (53), the interiors of the arc-shaped support frames (53) are fixedly mounted with short shafts (54), the interiors of the guide rails (50) are fixedly mounted with pneumatic cylinders (55), and the piston ends of the pneumatic cylinders (55) are fixedly connected to the sliding frames (51).

4. The dynamic pull-out test device for anchor rods under triaxial confining pressure according to claim 3, characterized in that: Telescopic rods (24) are fixedly installed on both sides of the bottom of the moving plate (22), the hydraulic cylinder (23) and the telescopic rod (24) are arranged between two guide rails (50), a plurality of square slots (43) are opened on one side of the moving plate (22), a plurality of square slots (40) are opened on one side of the table (6), electric push rods (42) are fixedly embedded on both sides of the table (6), and a plug-in frame (41) is fixedly installed on the piston end of the electric push rod (42).

5. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: The full-length bonded anchor rock model comprises a prefabricated anchor rod (30) and a casting model (29) fixedly mounted on the outside of the prefabricated anchor rod (30); a positioning rod (56) is fixedly mounted on one end of the casting model (29) away from the prefabricated anchor rod (30); a circular hole (31) is provided on the outside of the prefabricated anchor rod (30) and the positioning rod (56); and an arc-shaped groove (39) is provided on one side of the prefabricated anchor rod (30).

6. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: The confining pressure applying structure includes three double-axis hydraulic cylinders (25) fixedly mounted on the top of the moving plate (22) and a hydraulic cylinder three (46) arranged on one side of the drawing steel plate (20), the two piston ends of the double-axis hydraulic cylinders (25) are fixedly mounted with a fixed vertical plate (26), the top of the fixed vertical plate (26) is fixedly mounted with a clamping frame (28), and the two sides of the double-axis hydraulic cylinders (25) are provided with telescopic rods (27), the piston ends of the two telescopic rods (27) are fixedly connected to the front fixed vertical plate (26), and the outer shell of the telescopic rods (27) is fixedly connected to the rear fixed vertical plate (26).

7. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 6, characterized in that: A positioning plate (47) is fixedly installed on the piston end of the hydraulic cylinder three (46), a mounting frame four (45) is fixedly installed on the outer side of the hydraulic cylinder three (46), a plurality of fixed bent plates (44) are fixedly installed between the mounting frame four (45) and the table two (6), a guide shaft (49) is slidably inserted on the mounting frame four (45), one end of the guide shaft (49) is fixedly connected to the positioning plate (47), an empty groove (48) is provided at the bottom of the positioning plate (47), an electromagnet (37) is fixedly embedded on the side of the positioning plate (47) close to the mounting frame four (45), and an arc-shaped groove one (38) is provided on the side of the linkage frame (19) close to the mounting frame four (45).

8. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: The positioning structure includes a hydraulic cylinder 2 (36) fixedly mounted on the drawing steel plate (20), a U-shaped frame (34) fixedly mounted on the piston end of the hydraulic cylinder 2 (36), and a plug-in shaft (35) fixedly mounted on the U-shaped frame (34). The top of the drawing steel plate (20) is provided with a circular hole 3 (33) and two circular holes 2 (32). Both ends of the U-shaped frame (34) extend into the inside of the two circular holes 2 (32), respectively. The hydraulic cylinder 2 (36) is arranged in one of the circular holes 2 (32) and is fixedly connected to the drawing steel plate (20). The bottom end of the plug-in shaft (35) passes through the circular hole 3 (33).

9. The anchor bolt dynamic pullout test device under triaxial confining pressure environment according to claim 1, characterized in that: The power loading structure comprises a high-pressure pump (10) fixedly mounted on the bottom of table 2 (6), a one-way valve (9) fixedly mounted on the air outlet end of the high-pressure pump (10), a pressure box (7) fixedly connected to one end of the one-way valve (9), a solenoid valve (11) fixedly connected to one side of the pressure box (7), a connecting pipe (12) fixedly connected to one end of the solenoid valve (11), and an ejection frame (13) fixedly connected to one end of the connecting pipe (12), wherein an injection rod (15) is inserted into the ejection frame (13), a plurality of mounting frames (14) are fixedly mounted between the outer side of the ejection frame (13) and table 2 (6), the pressure box (7) is fixedly penetrated on table 2 (6), and an air pressure sensor (8) is fixedly mounted on the outer side of the pressure box (7).

10. A method for dynamic pull-out testing of anchor rods, applicable to the dynamic pull-out testing apparatus for anchor rods under triaxial confining pressure as claimed in any one of claims 1 to 9, characterized in that: The steps include: Step 1: Install three full-length bonded anchored rock models on the model support structure, control the two pneumatic cylinders (55) to work for the first time, and move the front-most full-length bonded anchored rock model to the bottom of the reserved channel (21); Step 2: Control the hydraulic cylinder 1 (23) to work, and the six clamping frames (28) are distributed to the front and rear sides of the full-length bonded anchored rock model at the front side. Then, the three biaxial hydraulic cylinders (25) work and contract, and the six clamping frames (28) move to the outside of the casting model (29); then, the computer (2) controls the hydraulic cylinder 1 (23) to continue to extend, and the full-length bonded anchored rock model moves up to the top of the table 2 (6), and the moving plate (22) moves up to the inside of the reserved channel (21); Step 3: Control the two electric push rods (42) to work and retract, completing the transmission relationship between the motion plate (22) and the table 2 (6); Step 4: The electromagnet (37) works, and the electromagnet (37) is fixed to the drawing steel plate (20) by magnetic force, and controls the hydraulic cylinder (46) to work and extend. After a period of time, when the circular hole (33) opened on the drawing steel plate (20) is aligned with the circular hole (31) opened on the prefabricated anchor rod (30), the electromagnet (37) stops working, and finally the positioning plate (47) is against the casting model (29); the hydraulic cylinder (36) works and contracts, and the hydraulic cylinder (36) drives the U-shaped frame (34) to move downward, and the plug-in shaft (35) passes through the circular hole (33) and the circular hole (31) opened on the prefabricated anchor rod (30); Step 5: Adhere two resistance strain gauges (16) to the outside of the prefabricated anchor rod (30) and the outside of one end of the incident rod (15) located outside the ejection frame (13), and set the air pressure value to be reached inside the pressure box (7) on the computer (2); Step 6: The computer (2) controls the power loading structure to work according to a preset program, and the high-pressure gas ejects the incident rod (15), and one end of the incident rod (15) hits the linkage frame (19); Step 7: Repeat step 6 multiple times. After a step 6 is completed, the computer (2) first controls the hydraulic cylinder 3 (46) to contract, and the positioning plate (47) applies a certain static load to the drawn steel plate (20); Step 8: Remove the resistance strain gauge (16); control the hydraulic cylinder 2 (36) to extend, and the plug-in shaft (35) leaves the inside of the circular hole 1 (31); then control the hydraulic cylinder 3 (46) to work and contract, control the electromagnet (37) to work, the positioning plate (47) drives the electromagnet (37) to move toward the drawing steel plate (20), the electromagnet (37) drives the drawing steel plate (20) to move synchronously, and the linkage frame (19) moves synchronously; Step 9: Control the electric push rod (42) to extend, the plug-in frame (41) is separated from the contact with the moving plate (22), control the hydraulic cylinder (23) to work and retract, and the moving plate (22) moves downward; the double-axis hydraulic cylinder (25) works and extends, the clamping frame (28) is separated from the casting model (29), and the hydraulic cylinder (23) continues to work to drive the moving plate (22) to move downward.

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