Pre-stressed anchor cable testing device

Abstract

The invention discloses a pre-stressed anchor cable testing device which comprises a base, two ends of the upper side of the base are fixedly connected with gantries respectively, a beam plate is arranged between the two gantries, anchoring holes are formed in the bottom of the beam plate, simulated surrounding rock is arranged around the anchoring holes, baffles are arranged on two sides of the simulated surrounding rock, and sliding grooves are formed in the sides, close to the simulated surrounding rock, of the baffles. At least one sliding plate is slidably connected into the sliding groove, and a plurality of supporting rods are sequentially hinged to one side of the sliding plate. A reference shaft is arranged between every two adjacent supporting rods, the supporting rods are rotationally arranged on the reference shafts in a staggered mode, and limiting devices for limiting relative rotation of the supporting rods and the reference shafts are arranged in the reference shafts. Hooks are arranged at the lower ends of the sliding plates. The device has the advantages that free rotation is achieved through the multiple supporting rods and the reference shafts between the adjacent supporting rods, the larger the number of the supporting rods is, the smaller the interference to the simulated surrounding rock is, and the vertical shear test of the simulated surrounding rock is not affected.

Description

Technical Field

[0001] This invention relates to the field of prestressed anchor cable testing technology, and more particularly to a prestressed anchor cable testing device. Background Technology

[0002] After tunnel excavation, the disruption of the original stress balance often leads to instability, increasing safety hazards. To ensure the stability of tunnel components after stress redistribution, measures such as steel supports and anchor cables are introduced. Among these measures, the effective prestress of prestressed anchor cables is crucial for the long-term stable operation of tunnel components.

[0003] By applying prestress, the loose and fractured rock mass is anchored in the upper, unloose rock layer. Existing anchor cable process tests are divided into non-destructive (single-cycle) tests and destructive tests. Tension tests are used to test the anchoring strength. However, this method of tensioning the anchor cable can only test the connection strength between the anchor cable and the anchor cable hole. It is insufficient to verify whether the reinforcement strength requirements are met for cracks or loose surrounding rock that are a certain distance away from the anchor cable. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a prestressed anchor cable testing device, thereby solving the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A prestressed anchor cable test device includes a base, with gantry frames fixedly connected to both ends of the upper side of the base, a beam plate between the two gantry frames, anchor holes at the bottom of the beam plate, simulated surrounding rock around the anchor holes, baffles on both sides of the simulated surrounding rock, a chute on the side of the baffle closest to the simulated surrounding rock, at least one sliding plate slidably connected in the chute, and multiple support rods sequentially hinged to one side of the sliding plate. A reference axis is set between adjacent support rods, and the support rods are offset and rotated on the reference axis. A limiting device is provided in the reference axis to restrict the relative rotation of the support rods and the reference axis. A hook is installed at the bottom of the skateboard.

[0006] Preferably, the limiting device includes an isosceles trapezoidal block, the reference shaft is a hollow structure, the isosceles trapezoidal block is slidably connected inside the reference shaft, two push rods are slidably connected at an offset distance from the outer circle of the reference shaft, one end of each push rod extending into the reference shaft is fixedly connected to an inclined block, the inclined block is arranged corresponding to the waist surface of the isosceles trapezoidal block, a limiting plate is fixedly connected to the outside of each push rod, and a rotating sleeve is fixedly connected to the end of each support rod. The rotating sleeve is rotatably connected to the reference shaft, and the limiting plate is pressed against the inner wall of the rotating sleeve to limit the rotation of the reference shaft and the rotating sleeve. The outer wall of the reference shaft is provided with a clearance hole, and a steel wire rope is inserted into the clearance hole. The support rod is a hollow rod, and the steel wire rope passes through the support rod and the reference shaft and is fixedly connected to the isosceles trapezoidal block in each reference shaft.

[0007] Preferably, the lower end of the slide plate is provided with a sliding cavity, a sliding column is slidably connected in the sliding cavity, the hook is threadedly connected to the sliding column, the slide plate is provided with a rope receiving channel, and the wire rope passes through the rope receiving channel and is fixedly connected to the sliding column.

[0008] Preferably, an arc-shaped guide rail is fixedly connected between the two gantry frames. The beam plate includes a fixed beam and a sunken beam located on both sides of the fixed beam. The fixed beam is fixedly connected to the arc-shaped guide rail by a hanger. The anchor hole is located on the inner arc surface of the fixed beam. The arc-shaped guide rail is provided with a first slide block. The first slide block is fixedly connected to a first hydraulic rod. The telescopic end of the first hydraulic rod is hinged to the sunken beam.

[0009] Preferably, a wedge plate is slidably connected between the sunken beam and the fixed beam, dovetail plates are provided on both sides of the wedge plate, and a dovetail groove is provided on the side of the fixed beam. The dovetail plates and the dovetail grooves are adapted to each other. A second slide is provided on the arc-shaped guide rail, and a second hydraulic rod is fixedly connected to the second slide. The telescopic end of the second hydraulic rod is hinged to the wedge plate.

[0010] Preferably, slots are provided on opposite sides of the two baffles, and arc-shaped templates are inserted into the slots.

[0011] This invention provides a testing device for prestressed anchor cables. It has the following beneficial effects: (1) The present invention uses multiple support rods and reference axes between adjacent support rods to achieve free rotation. The more support rods there are, the less interference there is to the simulated surrounding rock. It does not affect the vertical shear test of the simulated surrounding rock. When the vertical shear test is no longer needed, each reference axis is locked with a support rod, that is, a rigid rod with a custom shape is formed in the simulated surrounding rock. It can peel off the simulated surrounding rock for cracks, thereby measuring the reinforcement strength of the anchor to the surrounding rock and the grouting penetration status.

[0012] (2) The wedge plate of the present invention allows the components inside the arched beam to descend through the second hydraulic rod. The first hydraulic rod pushes down the sinking beam, and the simulated surrounding rock at the bottom of the sinking beam and the simulated surrounding rock at the bottom of the fixed beam form a shear force. The strength, displacement, deformation, etc. after reinforcement are measured by existing monitoring instruments. By using modular fixed beams and sinking beams, fixed beams and sinking beams with different arc length ratios can be designed to bring the shear force position closer to or further away from the anchor cable to meet different test requirements. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the basic structure of the present invention; Figure 2 This is a schematic diagram of a partially cut section of the present invention; Figure 3yes Figure 2 A magnified view of a portion of point H in the image; Figure 4 This is a schematic diagram of the connection structure between the skateboard and the short stick; Figure 5 This is an exploded view of the connection structure between the short rod and the reference axis. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0015] Please see Figures 1 to 5 This invention provides a technical solution: a prestressed anchor cable test device, including a base 1, with gantry 11 fixedly connected to both ends of the upper side of the base 1, a beam plate 2 between the two gantry 11, an anchoring hole 21 at the bottom of the beam plate 2, and simulated surrounding rock 10 around the anchoring hole 21. The simulated surrounding rock 10 is prepared by existing technology and has cracks 20. Baffles 3 are set on both sides of the simulated surrounding rock 10, and slots 311 are set on the opposite side of the two baffles 3. Arc-shaped templates are inserted into the slots 311. The upper side of the arc-shaped templates, the bottom of the beam plate 2, the baffles 3 on both sides, and the front and rear surrounding plates form a filling cavity. The simulated surrounding rock 10 is prepared by crushed stone and gel material in the filling cavity by existing technology. A chute 31 is set on the side of the baffle 3 near the simulated surrounding rock 10. At least one slide plate 32 is slidably connected in the chute 31. A hook 4 is set at the lower end of the slide plate 32. The hook 4 is used to connect a tensioner (an existing device for measuring tension) to break the simulated surrounding rock 10 and detect the force.

[0016] Multiple support rods 33 are sequentially hinged to one side of the slide plate 32. For clarity, only two support rods 33 are shown in the accompanying drawings of this invention, and the apparent length is not the actual size used. They are only for the purpose of demonstrating the working principle of this invention. A reference shaft 34 is provided between adjacent support rods 33, and the support rods 33 are offset and rotatably mounted on the reference shaft 34. A limiting device is provided in the reference shaft 34 to restrict the relative rotation of the support rods 33 and the reference shaft 34. This invention involves drilling holes 21 into simulated surrounding rock 10, installing anchor cables in the holes, grouting and sealing the anchors, and conducting reinforcement tests on the rock mass by setting different prestress parameters. The tension test of the prestressed anchor cables is existing technology and will not be described in detail here. After anchoring, it is necessary to test the reinforcement strength of the surrounding rock. By using necessary detection methods such as magnetically mounting dial gauges or displacement sensors on baffle 3 or embedding sensors in simulated surrounding rock 10, the deformation at the bottom of simulated surrounding rock 10 is monitored, thereby simulating the application of additional stress from above, and whether the reinforced simulated surrounding rock 10 can withstand the test pressure without cracking or deforming. After the pressure test, the layered stripping of the simulated surrounding rock 10 can detect the penetration and reinforcement of the grout in the simulated surrounding rock 10. The existing technology sets a rod embedded in the simulated surrounding rock 10 on the pull plate on the side. The rod descends with the pull plate and then strips the part of the simulated surrounding rock 10 below the rod, thus achieving the purpose of the test. Then, the rod in this way acts as a skeleton in the simulated surrounding rock 10, which is an interference factor that is not present in the existing tunnel anchoring construction. It seriously interferes with the shear failure of the surrounding rock and causes the test to be inaccurate.

[0017] To overcome the above-mentioned defects, the present invention uses multiple support rods 33 and a reference axis 34 between adjacent support rods 33 to allow free rotation. The more support rods 33 are set, the less interference there is with the simulated surrounding rock 10, and the less impact there is on the vertical shear test of the simulated surrounding rock 10. When the vertical shear test is no longer needed, each reference axis 34 locks the support rod 33, that is, a rigid rod of a custom shape is formed in the simulated surrounding rock 10 (when preparing the simulated surrounding rock 10, multiple support rods 33 are rotated and arranged around the reference axis 34 to form the required shape and then filled with aggregate). The simulated surrounding rock 10 can be peeled off for cracks 20, thereby measuring the reinforcement strength of the anchor to the surrounding rock and the grouting penetration status.

[0018] This invention provides further technical solutions, such as... Figures 1 to 5 As shown, the limiting device includes an isosceles trapezoidal block 5, a reference shaft 34 with a hollow structure, the isosceles trapezoidal block 5 is slidably connected inside the reference shaft 34, two push rods 51 are slidably connected to the outer circle of the reference shaft 34 at a misalignment, one end of each push rod 51 is fixedly connected to an inclined block 52, the inclined block 52 is set corresponding to the waist surface of the isosceles trapezoidal block 5, a limiting plate 53 is fixedly connected to the outside of each push rod 51, the limiting plate 53 is provided with multiple protrusions, a rotating sleeve 54 is fixedly connected to the end of each support rod 33, the inner wall of the rotating sleeve 54 is provided with multiple slots, the slots are set corresponding to the protrusions, the rotating sleeve 54 is rotatably connected to the reference shaft 34, and the limiting plate 53 is pressed against the inner wall of the rotating sleeve 54 to limit the rotation of the reference shaft 34 and the rotating sleeve 54; A clearance hole 55 is provided on the outer wall of the reference shaft 34, and a steel wire rope 56 is inserted into the clearance hole 55. The support rod 33 is a hollow rod, and the steel wire rope 56 passes through the support rod 33 and the reference shaft 34 and is fixedly connected to the isosceles trapezoidal block 5 in each reference shaft 34.

[0019] The lower end of the slide plate 32 is provided with a sliding cavity 6, and a sliding column 61 is slidably connected inside the sliding cavity 6. The hook 4 is threadedly connected to the sliding column 61. The slide plate 32 is provided with a rope receiving channel 62, and the wire rope 56 passes through the rope receiving channel 62 and is fixedly connected to the sliding column 61.

[0020] This invention uses a pull hook 4 to lower a sliding column 61 into a sliding cavity 6 and tension a steel wire rope 56. The waist surface of the isosceles trapezoidal block 5 on the steel wire rope 56 acts on the inclined block 52 through the inclined plane, causing the push rod 51 and the limiting plate 53 to be pressed against the inner wall of the rotating sleeve 54 to limit the rotation of the reference shaft 34 and the rotating sleeve 54. All the support rods 33 form a rigid rod of a custom shape within the simulated surrounding rock 10. After the sliding column 61 is limited by the lower end of the sliding cavity 6, it forms an overall pull on the sliding plate 32 and the rigid rod of the custom shape. Thus, without affecting the shear failure test, it can perform a layered peeling test on the simulated surrounding rock 10, thereby verifying a more comprehensive and complete test.

[0021] This invention provides further technical solutions, such as... Figures 1 to 5 As shown, an arc-shaped guide rail 22 is fixedly connected between the two gantry frames 11. The beam plate 2 includes a fixed beam 23 and sinking beams 24 located on both sides of the fixed beam 23. The arc length of the fixed beam 23 and the sinking beams 24 on both sides is selected according to the design requirements and is modular to facilitate test diversity. The fixed beam 23 is fixedly connected to the arc-shaped guide rail 22 through a hanger. The anchor hole 21 is located on the inner arc surface of the fixed beam 23. The arc-shaped guide rail 22 is provided with a first slide 25. The first slide 25 is fixedly connected to a first hydraulic rod 26. The telescopic end of the first hydraulic rod 26 is hinged to the sinking beam 24.

[0022] A wedge plate 27 is slidably connected between the sunken beam 24 and the fixed beam 23. Dovetail plates 271 are provided on both sides of the wedge plate 27, and a dovetail groove is provided on the side of the fixed beam 23. The dovetail plates 271 are adapted to the dovetail groove. A second slide block 28 is provided on the arc-shaped guide rail 22. The second slide block 28 is fixedly connected to the second hydraulic rod 29. The telescopic end of the second hydraulic rod 29 is hinged to the wedge plate 27.

[0023] This invention uses a wedge plate 27 and a second hydraulic rod 29 to create space for the components inside the arched beam 2 to descend. The first hydraulic rod 26 pushes down the sinking beam 24, and the simulated surrounding rock 10 at the bottom of the sinking beam 24 forms a shear force with the simulated surrounding rock 10 at the bottom of the fixed beam 23 (for destructive or non-destructive testing). The strength after reinforcement is measured using existing monitoring instruments. By using modular fixed beams 23 and sinking beams 24, and designing fixed beams 23 and sinking beams 24 with different arc length ratios, the shear force position can be placed closer to or further away from the anchor cable to meet different test requirements.

[0024] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A prestressed anchor cable test device, comprising a base (1), with gantry (11) fixedly connected to both ends of the upper side of the base (1), a beam plate (2) arranged between the two gantry (11), an anchor hole (21) provided at the bottom of the beam plate (2), simulated surrounding rock (10) arranged around the anchor hole (21), and baffles (3) arranged on both sides of the simulated surrounding rock (10), characterized in that: The baffle (3) is provided with a chute (31) on the side near the simulated surrounding rock (10). At least one slide plate (32) is slidably connected in the chute (31). Multiple support rods (33) are sequentially hinged to one side of the slide plate (32). A reference shaft (34) is provided between adjacent support rods (33), and the support rods (33) are offset and rotated on the reference shaft (34). A limiting device is provided in the reference shaft (34) to restrict the relative rotation of the support rods (33) and the reference shaft (34). A hook (4) is provided at the lower end of the skateboard (32).

2. The prestressed anchor cable testing device according to claim 1, characterized in that: The limiting device includes an isosceles trapezoidal block (5), a reference shaft (34) with a hollow structure, the isosceles trapezoidal block (5) is slidably connected inside the reference shaft (34), and two push rods (51) are slidably connected to the outer circle of the reference shaft (34) with offset. One end of each push rod (51) extending into the reference shaft (34) is fixedly connected to an inclined block (52). The inclined block (52) is set corresponding to the waist surface of the isosceles trapezoidal block (5). A limiting plate (53) is fixedly connected to the outside of each push rod (51), and a rotating sleeve (54) is fixedly connected to the end of each support rod (33). The rotating sleeve (54) is rotatably connected to the reference shaft (34). The limiting plate (53) is pressed against the inner wall of the rotating sleeve (54) to limit the rotation of the reference shaft (34) and the rotating sleeve (54). The outer wall of the reference shaft (34) is provided with a clearance hole (55), and a steel wire rope (56) is inserted into the clearance hole (55). The support rod (33) is a hollow rod. The steel wire rope (56) passes through the support rod (33) and the reference shaft (34) and is fixedly connected to the isosceles trapezoidal block (5) in each reference shaft (34).

3. The prestressed anchor cable testing device according to claim 2, characterized in that: The lower end of the slide plate (32) is provided with a sliding cavity (6), and a sliding column (61) is slidably connected inside the sliding cavity (6). The hook (4) is threadedly connected to the sliding column (61). The slide plate (32) is provided with a rope receiving channel (62), and the wire rope (56) passes through the rope receiving channel (62) and is fixedly connected to the sliding column (61).

4. The prestressed anchor cable testing device according to claim 1, characterized in that: An arc-shaped guide rail (22) is fixedly connected between two gantry frames (11). The beam plate (2) includes a fixed beam (23) and a sunken beam (24) located on both sides of the fixed beam (23). The fixed beam (23) is fixedly connected to the arc-shaped guide rail (22) through a hanger. The anchor hole (21) is located on the inner arc surface of the fixed beam (23). The arc-shaped guide rail (22) is provided with a first slide (25). The first slide (25) is fixedly connected to a first hydraulic rod (26). The telescopic end of the first hydraulic rod (26) is hinged to the sunken beam (24).

5. The prestressed anchor cable testing device according to claim 4, characterized in that: A wedge plate (27) is slidably connected between the sinking beam (24) and the fixed beam (23). Dovetail plates (271) are provided on both sides of the wedge plate (27). A dovetail groove is provided on the side of the fixed beam (23). The dovetail plate (271) is adapted to the dovetail groove. A second slide (28) is provided on the arc-shaped guide rail (22). The second slide (28) is fixedly connected to the second hydraulic rod (29). The extension end of the second hydraulic rod (29) is hinged to the wedge plate (27).

6. The prestressed anchor cable testing device according to claim 1, characterized in that: Slots (311) are provided on the opposite side of the two baffles (3), and arc-shaped templates are inserted into the slots (311).

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