Anchor rod pull-out test device

Abstract

The invention discloses an anchor rod pull-out test device, and particularly relates to the technical field of pull-out test devices, and the anchor rod pull-out test device comprises a confining pressure loading mechanism which comprises a confining pressure box for placing an anchor rod test piece and three groups of independent confining pressure loading units which are respectively installed at the top, the left side and the right side of the confining pressure box, each confining pressure loading unit comprises a loading end and a confining pressure driving assembly, and the confining pressure driving assembly drives the loading end to move towards the anchor rod test piece; the axial tension loading mechanism comprises a clamping head assembly and a tension driving device, one end of the clamping head assembly is used for being connected with an anchor rod of the anchor rod test piece in a clamping mode, the other end of the clamping head assembly is connected with the tension driving device, and the clamping head assembly is driven by the tension driving device to move in the direction away from the anchor rod test piece; and the confining pressure driving assemblies and the stretching driving devices are all in signal connection with the control system. The complex stress environment of an engineering site can be accurately simulated, test data conforming to actual working conditions are obtained, and the engineering economy and safety are effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of pull-out test devices, in particular to an anchor rod pull-out test device. Background Art

[0002] As tunnel construction extends deeper and into areas with complex geological conditions, tunnel construction in conditions of high geostress, weak, and fractured surrounding rock is becoming increasingly common. The resulting large deformation hazards of the surrounding rock have become a key technical challenge hindering safe tunnel construction. Among the many technologies for controlling surrounding rock deformation, anchor bolting, as an active support method, has been widely used due to its adaptability. However, engineering practice has shown that the support effectiveness of anchor bolts is significantly correlated with the confining pressure to which they are subjected. This stress sensitivity directly affects the reliability and durability of the anchor bolting system.

[0003] When conducting anchor bolt performance tests indoors, existing anchor bolt pull-out test devices typically place the anchor bolt under no confining pressure or constant confining pressure conditions for testing. However, preliminary theoretical calculations and experimental verification have shown that in actual engineering, the stress field distribution of the tunnel surrounding rock has obvious anisotropic characteristics, and there is a significant difference between the stress in the vertical and horizontal directions. This difference causes the experimental results obtained using traditional no confining pressure or constant confining pressure constraints to deviate significantly from the actual measured data on the engineering site, making it difficult to accurately reflect the mechanical properties and support effects of the anchor bolt under actual working conditions. Existing research shows that surrounding rock pressure has a significant impact on the performance of anchor bolt support. This impact is directly related to the rationality of the selection of support structure design parameters and the safety of engineering implementation. Traditional pull-out test devices can no longer meet the needs of accurately evaluating anchor bolt support performance. Therefore, developing a pull-out test device that can more accurately simulate the stress environment of the engineering site is of great significance for improving the scientific nature and reliability of tunnel support structure design. Summary of the Invention

[0004] The purpose of the present invention is to provide an anchor pull-out test device to solve the problems existing in the above-mentioned prior art, which can accurately simulate the complex stress environment of the engineering site, obtain test data that conforms to the actual working conditions, and effectively improve the economy and safety of the project.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides an anchor rod pulling test device, comprising: a confining pressure loading mechanism, comprising a confining pressure box and three groups of independent confining pressure loading units, the confining pressure box is used to place the anchor rod specimen, one group of the confining pressure loading units is installed on the top of the confining pressure box, and the other two groups of the confining pressure loading units are symmetrically installed on the left and right sides of the confining pressure box, each of the confining pressure loading units comprises a loading end and a confining pressure driving assembly, the loading end is driven by the confining pressure driving assembly so that the loading end can move toward the direction of the anchor rod specimen; an axial tension loading mechanism, comprising a clamping head assembly and a tensile driving device, one end of the clamping head assembly is used to be connected to the anchor rod of the anchor rod specimen, the other end of the clamping head assembly is connected to the tensile driving device, and the clamping head assembly is driven by the tensile driving device to move in a direction away from the anchor rod specimen; a control system, each of the confining pressure driving assemblies and the tensile driving device are connected to the control system signal.

[0007] Preferably, the confining pressure drive assembly includes nine confining pressure hydraulic cylinders, which are arranged in a 3×3 array on the loading end. The loading end includes three loading heads fitted side by side, and one loading head is provided with three confining pressure hydraulic cylinders, and the three confining pressure hydraulic cylinders on one loading head are connected in series through an oil pipe.

[0008] Preferably, the axial pulling loading mechanism also includes an axial pulling box, a horizontal moving unit and a vertical moving unit. The axial pulling box is fixedly connected to the back of the confining pressure box, the horizontal moving unit includes a horizontal guide rail, a horizontal moving plate and a horizontal driving device, the horizontal guide rail is arranged in the horizontal direction on the side of the axial pulling box away from the confining pressure box, the horizontal moving plate is slidably connected to the horizontal guide rail, and the horizontal moving plate is driven by the horizontal driving device to slide back and forth along the horizontal guide rail; the vertical moving unit includes a vertical guide rail, a vertical moving plate and a vertical driving device, the vertical guide rail is arranged on the horizontal moving plate, the vertical guide rail is perpendicular to the horizontal guide rail, the vertical moving plate is slidably connected to the vertical guide rail, and the vertical moving plate is driven by the vertical driving device to slide back and forth along the vertical guide rail; the stretching driving device is fixedly connected to the vertical moving plate.

[0009] Preferably, the horizontal driving device includes a first manual rocker, a horizontal screw rod, a horizontal nut, a horizontal moving block and a bearing seat frame, the bearing seat frame is fixed on the shaft pull box, the horizontal screw rod is rotatably installed in the bearing seat, the first manual rocker is fixedly connected to one end of the horizontal screw rod, the horizontal nut is threadedly connected to the horizontal screw rod, the horizontal moving block is fixedly connected to the horizontal nut, the moving block is slidingly connected to the horizontal guide rail, and the horizontal moving block is fixedly connected to the horizontal moving plate; the vertical driving device includes a second manual rocker, a gear, a vertical rack, a vertical moving block and a connecting rod, one end of the second manual rocker is fixedly connected to the gear, the gear is meshed with the vertical rack, the vertical rack is connected to the vertical moving block through the connecting rod, the vertical moving block is slidably connected to the vertical guide rail, and the vertical moving block is fixedly connected to the vertical moving plate.

[0010] Preferably, the stretching drive device includes a stretching hydraulic cylinder, the cylinder body of the stretching hydraulic cylinder is fixedly connected to the side of the vertical movable plate away from the vertical guide rail, the vertical movable plate is provided with a first through hole through which the piston rod of the stretching hydraulic cylinder can pass, and the horizontal movable plate is provided with a second through hole through which the piston rod of the stretching hydraulic cylinder can pass, and the end of the piston rod of the stretching hydraulic cylinder away from the cylinder body passes through the first through hole and the second through hole in sequence and is fixedly connected to the clamping head assembly.

[0011] Preferably, the clamping head assembly includes a clamping head body and a ball joint, the ball joint includes a ball seat, a ball head and a ball rod, the ball head is fixedly connected to the ball rod, the ball seat is rotatably sleeved outside the ball head, one end of the clamping head body is used to fix the anchor rod of the anchor rod specimen, the other end of the clamping head body is fixedly connected to the ball rod, the ball seat is fixedly connected to the piston rod of the stretching hydraulic cylinder, and the ball rod is provided with a tension sensor for detecting the tensile force.

[0012] Preferably, it also includes a sample delivery mechanism, which includes a sample delivery trolley and a sample delivery track. The sample delivery track is fixedly connected to the confining pressure box, and one end of the sample delivery track can extend into the confining pressure box. The sample delivery trolley is slidably connected to the sample delivery track, and the top of the sample delivery trolley is used to place the anchor rod specimen.

[0013] Preferably, the sample delivery trolley includes a top plate, a spring support, a load-bearing frame and a roller. The top plate is connected to the load-bearing frame through the spring support, the roller is installed on the load-bearing frame, and the top plate is used to place the anchor rod specimen.

[0014] Preferably, the confining pressure box includes a protective door and an arched limit platform, the protective door is installed on the front side of the confining pressure box, and the arched limit platform is provided on the rear side of the confining pressure box, the top of the arched limit platform is used to fit with the top of the loading head and the top of the end face of the anchor rod of the anchor rod specimen, the left side of the arched limit platform is used to fit with the left side of the end face of the anchor rod of the loading head and the anchor rod specimen on the left, and the right side of the arched limit platform is used to fit with the right side of the end face of the anchor rod of the loading head and the anchor rod specimen on the right.

[0015] Preferably, the confining pressure drive assembly also includes a top pressure transmitter and a side pressure transmitter, the top pressure transmitter is connected to the confining pressure loading unit at the top of the confining pressure box, and is used to detect the pressure applied by the confining pressure loading unit at the top; the side pressure transmitter is connected to the confining pressure loading unit on the left or right side of the confining pressure box, and is used to detect the pressure applied by the confining pressure loading unit on the left or right side, and the top pressure transmitter and the side pressure transmitter are both connected to the control system signal.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The present invention provides an anchor pull-out test device, which includes three groups of independent confining pressure loading units respectively installed on the top, left side and right side of the confining pressure box. The device can apply unequal confining pressures to the anchor specimen in the vertical and horizontal directions. At the same time, the tensile drive device drives the clamping head assembly to apply a pulling force to the anchor of the anchor specimen. The forces in the three directions perpendicular to each other are independent of each other, and can more accurately simulate the complex stress environment of the engineering site, obtain test data that conforms to actual working conditions, and provide more reliable technical support for the optimized design of the tunnel support structure, thereby effectively improving the economy and safety of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 This is a structural diagram of the anchor pull-out test device;

[0020] Figure 2 It is a side view of the anchor pull-out test device;

[0021] Figure 3 It is a cross-sectional view of the anchor pull-out test device;

[0022] Figure 4This is a schematic diagram of the back of the confining pressure loading mechanism;

[0023] Figure 5 Schematic diagram of the shaft pulling loading mechanism (the shaft pulling box is not shown);

[0024] Figure 6 for Figure 3 Enlarged view of part A.

[0025] In the figure: 1-sample delivery trolley; 2-sample delivery track; 3-top plate; 4-spring support; 5-load-bearing frame; 6-roller; 7-confining pressure box; 8-protective door; 9-arch limit platform; 10-confining pressure loading unit; 11-confining pressure hydraulic cylinder; 12-loading head; 13-top pressure transmitter; 14-side pressure transmitter; 15-axle pull box; 16-horizontal guide rail; 17-horizontal moving plate; 18-first manual rocker; 19-water Flat screw; 20-horizontal nut; 21-horizontal moving block; 22-bearing seat; 23-vertical guide rail; 24-vertical moving plate; 25-second manual rocker; 26-vertical rack; 27-vertical moving block; 28-clamping head body; 29-ball joint; 30-ball seat; 31-ball head; 32-ball rod; 33-tension sensor; 34-rubber pad; 35-anchor rod specimen; 36-tension hydraulic cylinder; 37-piston rod. DETAILED DESCRIPTION

[0026] 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.

[0027] The purpose of the present invention is to provide an anchor pull-out test device to solve the problems existing in the above-mentioned prior art, which can accurately simulate the complex stress environment of the engineering site, obtain test data that conforms to the actual working conditions, and effectively improve the economy and safety of the project.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] The present invention provides an anchor pull-out test device, such as Figure 1-Figure 3As shown, it includes: a confining pressure loading mechanism, including a confining pressure box 7 and three groups of independent confining pressure loading units 10, the confining pressure box 7 is used to place the anchor specimen 35, one group of confining pressure loading units 10 is installed on the top of the confining pressure box 7, and the other two groups of confining pressure loading units 10 are symmetrically installed on the left and right sides of the confining pressure box 7, each confining pressure loading unit 10 includes a loading end and a confining pressure drive assembly, the loading end is driven by the confining pressure drive assembly, so that the loading end can move toward the direction of the anchor specimen 35; an axial tension loading mechanism, including a clamping head assembly and a tensile drive device, one end of the clamping head assembly is used to clamp the anchor of the anchor specimen 35, and the other end of the clamping head assembly is connected to the tensile drive device, and the clamping head assembly is driven by the tensile drive device to move in the direction away from the anchor specimen 35; a control system, each confining pressure drive assembly and the tensile drive device are connected to the control system signal. Three independent confining pressure loading units 10 are respectively installed on the top, left side and right side of the confining pressure box 7, which can apply two mutually perpendicular and independently adjustable confining pressure loads on the side and top surfaces of the specimen. At the same time, the tensile drive device drives the clamping head assembly to apply an axial tensile load to the anchor rod of the anchor rod specimen 35. Through the synergistic effect of the loads in three directions, a true triaxial stress state in which the three stresses are mutually perpendicular and unequal can be formed in the specimen. This can more accurately simulate the complex stress environment of the engineering site, obtain test data that conforms to the actual working conditions, and provide more reliable technical support for the optimal design of the tunnel support structure, thereby effectively improving the economy and safety of the project.

[0030] In an embodiment of the present invention, it is further preferred that the confining pressure drive assembly includes nine confining pressure hydraulic cylinders 11, which are arranged in a 3×3 array on the loading end. The loading end includes three loading heads 12 arranged side by side. Three confining pressure hydraulic cylinders 11 are provided on each loading head 12, and the three confining pressure hydraulic cylinders 11 on each loading head 12 are connected in series via a single oil pipe, each of which is provided with a needle valve. The three hydraulic cylinders connected in series via a single oil pipe correspond to one loading head, and one loading head corresponds to one loading point, i.e., three loading points are evenly distributed on each loading end. The even distribution of multiple loading points can disperse the pressure over a larger area of the anchor specimen 35, making the stress on each part of the anchor specimen 35 relatively uniform, closer to the stress state of the material in actual engineering. This avoids the situation where, when there are bumps on the surface of the anchor specimen 35, there are too few loading points, which causes the specimen surface to receive pressure only at the bumps, resulting in uneven stress on the specimen, thereby ensuring that the test results are more practical and have greater application value. Evenly distributing multiple loading points can also improve the overall stability of the anchor rod specimen 35 and prevent the anchor rod specimen 35 from being locally damaged and unstable during the compression process.

[0031] It is further preferred in the embodiment of the present invention that the axial pulling loading mechanism also includes an axial pulling box 15, a horizontal moving unit and a vertical moving unit. The axial pulling box 15 is fixedly connected to the back of the confining pressure box 7. The horizontal moving unit includes a horizontal guide rail 16, a horizontal moving plate 17 and a horizontal driving device. A horizontal guide rail 16 is arranged in the horizontal direction on the side of the axial pulling box 15 away from the confining pressure box 7. The horizontal guide rail 16 is slidably connected to the horizontal guide rail 16. The horizontal moving plate 17 is driven by the horizontal driving device to slide back and forth along the horizontal guide rail 16; the vertical moving unit includes a vertical guide rail 23, a vertical moving plate 24 and a vertical driving device. The horizontal moving plate 17 is provided with a vertical guide rail 23. The vertical guide rail 23 is perpendicular to the horizontal guide rail 16. The vertical guide rail 23 is slidably connected to the vertical guide rail 24. The vertical moving plate 24 is driven by the vertical driving device to slide back and forth along the vertical guide rail 23; the stretching driving device is fixedly connected to the vertical moving plate 24.

[0032] It is further preferred in the embodiment of the present invention that the horizontal drive device includes a first manual rocker 18, a horizontal screw rod 19, a horizontal nut 20, a horizontal moving block 21 and a bearing seat frame 22, the bearing seat frame 22 is fixed on the shaft pull box 15, the horizontal screw rod 19 is rotatably installed in the bearing seat, the first manual rocker 18 is fixedly connected to one end of the horizontal screw rod 19, the horizontal nut 20 is threadedly connected to the horizontal screw rod 19, the horizontal moving block 21 is fixedly connected to the horizontal nut 20, the moving block is slidingly connected to the horizontal guide rail 16, and the horizontal moving block 21 is fixedly connected to the horizontal moving plate 17; the vertical drive device includes a second manual rocker 25, a gear, a vertical rack 26, a vertical moving block 27 and a connecting rod, one end of the second manual rocker 25 is fixedly connected to the gear, the gear is meshed with the vertical rack 26, the vertical rack 26 is connected to the vertical moving block 27 through a connecting rod, the vertical moving block 27 is slidingly connected to the vertical guide rail 23, and the vertical moving block 27 is fixedly connected to the vertical moving plate 24.

[0033] In an embodiment of the present invention, it is further preferred that the stretching drive device includes a stretching hydraulic cylinder 36, the cylinder body of the stretching hydraulic cylinder 36 is fixedly connected to the side of the vertical movable plate 24 away from the vertical guide rail 23, the vertical movable plate 24 is provided with a first through hole through which the piston rod 37 of the stretching hydraulic cylinder 36 can pass, and the horizontal movable plate 17 is provided with a second through hole through which the piston rod 37 of the stretching hydraulic cylinder 36 can pass, and the end of the piston rod 37 of the stretching hydraulic cylinder 36 away from the cylinder body passes through the first through hole and the second through hole in sequence and is fixedly connected to the clamping head assembly. By gradually injecting oil into the stretching hydraulic cylinder 36 to pressurize and load the tension, the piston rod 37 of the stretching hydraulic cylinder 36 pulls the clamping head assembly, causing the clamping head assembly fixedly connected to the anchor of the anchor specimen 35 to move in a direction away from the confining pressure loading mechanism, thereby realizing the anchor pulling work.

[0034] Preferably, the control system includes a hydraulic control unit, which includes an oil tank, an oil pump and an oil distribution valve. The oil suction port of the oil pump is connected to the oil tank, and the oil outlet of the oil pump is connected to the oil distribution valve through multiple oil pipelines. The nine confining pressure hydraulic cylinders 11 and the stretching hydraulic cylinder 36 are all connected to the oil distribution valve through oil pipelines, and each oil pipeline is provided with an independent needle valve.

[0035] It is further preferred in the embodiment of the present invention that Figure 5-Figure 6 As shown, the clamping head assembly includes a clamping head body 28 and a ball joint 29. The ball joint 29 includes a ball seat 30, a ball head 31 and a ball rod 32. The ball head 31 is fixedly connected to the ball rod 32. The ball seat 30 is rotatably sleeved outside the ball head 31. One end of the clamping head body 28 is used to fix the anchor rod of the anchor rod specimen 35. The other end of the clamping head body 28 is fixedly connected to the ball rod 32. The ball seat 30 is fixedly connected to the piston rod 37 of the stretching hydraulic cylinder 36. A tension sensor 33 for detecting the tensile force is provided on the ball rod 32. After adjustment by the horizontal moving unit and the vertical moving unit, the anchor rod and the piston rod 37 of the tensioning hydraulic cylinder 36 are made coaxial. However, the coaxiality of the anchor rod and the piston rod 37 of the tensioning hydraulic cylinder 36 is obtained by manual visual observation. The tension provided by the tensioning hydraulic cylinder 36 still has a slight deviation from the geometric axis of the anchor rod. The universal ball joint 29 can ensure that the tension provided by the tensioning hydraulic cylinder 36 is coaxial with the anchor rod, that is, the ball joint 29 allows this deviation to exist, and no secondary fine adjustment is required. The ball joint 29 can ensure that the tension is coaxial with the geometric axis of the anchor rod. Preferably, a clamping hole is opened on the clamping head body 28, and the anchor rod of the anchor rod specimen 35 can pass through the clamping hole, and then the anchor rod of the anchor rod specimen 35 is locked and fixed to the clamping head body 28 by a locking member.

[0036] Preferably, a rubber pad 34 is provided between the tension sensor 33 and the ball seat 30 of the ball joint 29. The rubber pad 34 can effectively reduce the sinking displacement of the whole composed of the clamping head body 28 and the tension sensor 33 due to its own gravity, reduce the obstruction to the operation of inserting the anchor rod into the clamping head body 28 and the centering work, and ensure the smooth progress of the experiment.

[0037] Before connecting the anchor rod of anchor specimen 35 to the axial tension loading mechanism, it is necessary to adjust the confining pressure loading mechanism to place the specimen in an initial stress state. First, adjust the top pressure to ensure that the specimen trolley is fixed and does not move forward or backward. Then adjust the horizontal pressure to the same level as the top pressure to place the specimen in an initial stress state and ensure that the anchor rod position does not move left or right before proceeding with the subsequent anchor rod centering work. When the anchor rod is aligning, by shaking the first manual crank, the horizontal nut 20 moves along the direction of the horizontal screw, and the horizontal nut 20 drives the horizontal moving block 21 to move along the horizontal guide rail 16, so that the horizontal moving plate 17 fixedly connected to the horizontal moving block 21 moves horizontally relative to the shaft pull box 15, realizing the horizontal movement of the stretching hydraulic cylinder 36; shaking the second manual crank, the vertical rack 26 moves along the vertical direction, and the vertical rack 26 drives the vertical moving block 27 to move up and down along the vertical guide rail 23, so that the vertical moving plate 24 fixedly connected to the vertical moving block 27 moves up and down relative to the horizontal moving plate 17, realizing the up and down movement of the stretching hydraulic cylinder 36; finally, adjust to the state where the geometric axis of the anchor rod coincides with the center axis of the clamping hole of the clamping head body 28 by visual observation.

[0038] It is further preferred in the embodiment of the present invention that the anchor rod pull-out test device also includes a sample delivery mechanism, the sample delivery mechanism includes a sample delivery trolley 1 and a sample delivery track 2, the sample delivery track 2 is fixedly connected to the confining pressure box 7, and one end of the sample delivery track 2 can extend into the confining pressure box 7, the sample delivery trolley 1 is slidably connected to the sample delivery track 2, and the top of the sample delivery trolley 1 is used to place the anchor rod specimen 35, the sample delivery trolley 1 includes a top plate 3, a spring support 4, a load-bearing frame 5 and a roller 6, the top plate 3 is connected to the load-bearing frame 5 through the spring support 4, the roller 6 is installed on the load-bearing frame 5, and is arranged on the sample delivery track 2, and the top plate 3 is used to place the anchor rod specimen 35. A support platform is provided in the confining pressure box 7, and the support platform is located in the middle of the sample delivery track 2. When the anchor rod specimen 35 is delivered to the confining pressure box 7 by the sample delivery trolley 1, when the top is not loaded, the spring support 4 between the top plate 3 and the load-bearing frame 5 can support the top plate 3 and the anchor rod specimen 35 placed on the top plate 3, so that there is a certain gap between the top plate 3 and the support platform. When the top confining pressure loading unit 10 loads and fixes the anchor rod specimen 35, the spring support 4 is deformed, and the gap between the top plate 3 and the support platform disappears. The support platform can avoid damaging the trolley, and the elastic force generated by the spring support 4 is just balanced with the deadweight of the top confining pressure loading unit 10. A reaction force is provided to the anchor rod specimen 35 through the spring support 4, which can offset the deadweight factor of the top confining pressure loading unit 10. The force applied to the anchor rod specimen 35 is only the hydraulic loading force, which makes the top loading confining pressure more accurate.

[0039] It is further preferred in the embodiment of the present invention that Figure 4As shown, the confining pressure box 7 includes a protective door 8 and an arched limit platform 9. The protective door 8 is installed on the front side of the confining pressure box 7. The rear side of the confining pressure box 7 is provided with an arched limit platform 9. The top of the arched limit platform 9 is used to fit with the top loading head 12 and the top of the end face of the anchor rod of the anchor rod specimen 35. The left side of the arched limit platform 9 is used to fit with the left side loading head 12 and the left side of the end face of the anchor rod of the anchor rod specimen 35. The right side of the arched limit platform 9 is used to fit with the right side loading head 12 and the right side of the end face of the anchor rod of the anchor rod specimen 35. Due to the pulling action, the anchor rod specimen 35 will generate friction on the loading head 12. The friction will cause the piston rod of the confining pressure hydraulic cylinder 11 to bend, thereby damaging the equipment. Therefore, the arched limit platform 9 can limit the loading head 12 from moving in three directions toward the axial pulling loading mechanism to avoid equipment damage. At the same time, the arched limit platform 9 can also limit the movement of the anchor rod specimen 35 toward the axial pulling loading mechanism to prevent the anchor rod specimen 35 from sliding out of the confining pressure box 7 due to the pulling force during the test, thereby ensuring the smooth progress of the experiment. Open the protective door 8, send the anchor rod specimen 35 into the confining pressure box 7 via the specimen trolley, and then close the protective door 8 to prevent debris from splashing during the confining pressure loading process of the anchor rod specimen 35 and accidentally injuring the operator.

[0040] In an embodiment of the present invention, it is further preferred that the confining pressure drive assembly also includes a top pressure transmitter 13 and a side pressure transmitter 14. The top pressure transmitter 13 is connected to the confining pressure loading unit 10 at the top of the confining pressure box 7 and is used to detect the pressure applied by the confining pressure loading unit 10 at the top; the side pressure transmitter 14 is connected to the confining pressure loading unit 10 on the left or right side of the confining pressure box 7 and is used to detect the pressure applied by the confining pressure loading unit 10 on the left or right side. The top pressure transmitter 13 and the side pressure transmitter 14 are both connected to the control system signal. During the test, the confining pressure applied at the top and the side is accurately measured by the top pressure transmitter 13 and the side pressure transmitter 14, which can ensure that the test is carried out under the preset pressure conditions, thereby obtaining accurate test data. Researchers can also adjust the output of the confining pressure loading unit 10 in a timely manner based on these real-time data to ensure that the confining pressure is always stable near the set value, thereby improving the reliability and repeatability of the test results.

[0041] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. An anchor pull-out test device, characterized in that: include: A confining pressure loading mechanism includes a confining pressure box and three independent confining pressure loading units. The confining pressure box is used to place the anchor specimen. One group of the confining pressure loading units is installed on the top of the confining pressure box, and the other two groups of the confining pressure loading units are symmetrically installed on the left and right sides of the confining pressure box. Each of the confining pressure loading units includes a loading end and a confining pressure drive assembly. The loading end is driven by the confining pressure drive assembly so that the loading end can move toward the anchor specimen. The axial tension loading mechanism includes a clamping head assembly and a tensile drive device, wherein one end of the clamping head assembly is used to clamp the anchor rod of the anchor rod specimen, and the other end of the clamping head assembly is connected to the tensile drive device, and the clamping head assembly is driven by the tensile drive device to move in a direction away from the anchor rod specimen; The control system is connected to the control system by signal.

2. The anchor pull-out test device according to claim 1, characterized in that: The confining pressure drive assembly includes nine confining pressure hydraulic cylinders, which are arranged in a 3×3 array on the loading end. The loading end includes three loading heads fitted side by side. Three confining pressure hydraulic cylinders are provided on one loading head, and the three confining pressure hydraulic cylinders on one loading head are connected in series through an oil pipe.

3. The anchor pull-out test device according to claim 1, characterized in that: The axial pulling loading mechanism also includes an axial pulling box, a horizontal moving unit and a vertical moving unit, the axial pulling box is fixedly connected to the back of the confining pressure box, the horizontal moving unit includes a horizontal guide rail, a horizontal moving plate and a horizontal driving device, the horizontal guide rail is arranged in the horizontal direction on the side of the axial pulling box away from the confining pressure box, the horizontal moving plate is slidably connected to the horizontal guide rail, and the horizontal moving plate is driven by the horizontal driving device to slide back and forth along the horizontal guide rail; the vertical moving unit includes a vertical guide rail, a vertical moving plate and a vertical driving device, the vertical guide rail is arranged on the horizontal moving plate, the vertical guide rail is perpendicular to the horizontal guide rail, the vertical moving plate is slidably connected to the vertical guide rail, and the vertical moving plate is driven by the vertical driving device to slide back and forth along the vertical guide rail; the stretching driving device is fixedly connected to the vertical moving plate.

4. The anchor pull-out test device according to claim 3, characterized in that: The cam is fixedly mounted on the support frame of the driving mechanism, and the cam is mounted on a link cam of the driving mechanism. The cam is mounted on a link cam of the driving mechanism. The cam is mounted on a link cam of the driving mechanism. The cam is mounted on a 5. The anchor pull-out test device according to claim 3, characterized in that: The stretching drive device includes a stretching hydraulic cylinder, the cylinder body of the stretching hydraulic cylinder is fixedly connected to the side of the vertical movable plate away from the vertical guide rail, the vertical movable plate is provided with a first through hole through which the piston rod of the stretching hydraulic cylinder can pass, and the horizontal movable plate is provided with a second through hole through which the piston rod of the stretching hydraulic cylinder can pass, and the end of the piston rod of the stretching hydraulic cylinder away from the cylinder body passes through the first through hole and the second through hole in sequence and is fixedly connected to the clamping head assembly.

6. The anchor pull-out test device according to claim 5, characterized in that: The clamping head assembly includes a clamping head body and a ball joint, the ball joint includes a ball seat, a ball head and a ball rod, the ball head is fixedly connected to the ball rod, the ball seat is rotatably sleeved outside the ball head, one end of the clamping head body is used to fix the anchor rod of the anchor rod specimen, the other end of the clamping head body is fixedly connected to the ball rod, the ball seat is fixedly connected to the piston rod of the stretching hydraulic cylinder, and the ball rod is provided with a tension sensor for detecting tensile force.

7. The anchor pull-out test device according to claim 1, characterized in that: It also includes a sample delivery mechanism, which includes a sample delivery trolley and a sample delivery track. The sample delivery track is fixedly connected to the confining pressure box, and one end of the sample delivery track can extend into the confining pressure box. The sample delivery trolley is slidably connected to the sample delivery track, and the top of the sample delivery trolley is used to place anchor rod specimens.

8. The anchor pull-out test device according to claim 7, characterized in that: The sample delivery trolley includes a top plate, a spring support, a load-bearing frame and a roller. The top plate is connected to the load-bearing frame through the spring support, the roller is installed on the load-bearing frame, and the top plate is used to place the anchor rod specimen.

9. The anchor pull-out test device according to claim 2, characterized in that: The confining pressure box includes a protective door and an arched limit platform, the protective door is installed on the front side of the confining pressure box, and the arched limit platform is provided on the rear side of the confining pressure box. The top of the arched limit platform is used to fit with the top of the loading head and the top of the end face of the anchor rod of the anchor rod specimen, the left side of the arched limit platform is used to fit with the left side of the loading head and the end face of the anchor rod of the anchor rod specimen on the left, and the right side of the arched limit platform is used to fit with the right side of the loading head and the end face of the anchor rod of the anchor rod specimen on the right.

10. The anchor pull-out test device according to claim 1, characterized in that: The confining pressure drive assembly also includes a top pressure transmitter and a side pressure transmitter. The top pressure transmitter is connected to the confining pressure loading unit at the top of the confining pressure box and is used to detect the pressure applied by the confining pressure loading unit at the top; the side pressure transmitter is connected to the confining pressure loading unit on the left or right side of the confining pressure box and is used to detect the pressure applied by the confining pressure loading unit on the left or right side. The top pressure transmitter and the side pressure transmitter are both connected to the control system signal.

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