Combined stress loading anchor rod rapid corrosion device and test method

Abstract

The invention discloses a combined stress loading anchor rod rapid corrosion device and a test method, and relates to the technical field of anchor rod corrosion tests.The combined stress loading anchor rod rapid corrosion device comprises a base, a test box, a vertical plate, a servo hydraulic station, an axial force loading unit, a radial force loading unit, a salt mist generator and a controller; a first cavity, a second cavity and a third cavity are arranged in the device, an axial force loading unit is arranged on the left side of each cavity, an anchor rod limiting mechanism is arranged on the right side of each cavity, and a radial force loading unit is arranged at the bottom of each cavity. Each chamber is provided with an electrocorrosion generation assembly, a ceramic heating sheet is fixedly embedded in the bottom of each chamber, a temperature and humidity monitor is arranged on the outer side of the test box, and the salt mist generator is arranged outside the test box. The three independent chambers in the test box are used for salt mist, raining, soaking and protolith state simulation corrosion tests respectively, so that the test efficiency is improved, the temperature in the box is convenient to regulate and control, and the accuracy of environmental simulation data is improved.

Description

Technical Field

[0001] The invention relates to the technical field of anchor rod corrosion testing, and in particular to a combined stress-loaded anchor rod rapid corrosion device and a construction method. Background Art

[0002] Anchor rods are the most basic component of tunnel support in contemporary coal mines. They can reinforce the surrounding rock of the tunnel so that the surrounding rock can support itself. Anchor rods are not only used in mines, but also in engineering technology to reinforce slopes, tunnels, and dam bodies. As a tensile member that penetrates deep into the stratum, one end of the anchor rod is connected to the engineering structure and the other end is deep in the stratum. Therefore, the anchor rod is easily corroded by humid environment or geological rock environment in the underground environment. In order to simulate and detect the corrosion factors of the anchor rod and the corrosion rate under different corrosion conditions, it is necessary to conduct rapid simulation experiments using an anchor rod corrosion test device that can be stress-loaded.

[0003] A Chinese patent with publication number CN112113825A discloses a prestressed multi-anchor corrosion test device and method. The anchor corrosion test device in the invention patent is to insert mortar anchors into a corrosion cylinder, pour a sufficient amount of corrosion liquid into the corrosion cylinder, and then fix the anchors through a supporting top plate and a supporting bottom plate, and then apply a loading force to the supporting bottom plate through a jack, thereby applying stress to the anchors for corrosion testing.

[0004] However, the stress applied by the prestressed multi-anchor corrosion test device and method is only axial stress, which cannot effectively simulate the corrosion process of the anchor rod when the surrounding rock is deformed in the well, and the axial stress data of the anchor rod during the whole corrosion process cannot be effectively detected. At the same time, the corrosion test is only a kind of corrosive liquid immersion test. Compared with the complex underground corrosion environment, the corrosion test data is relatively single, and it cannot effectively simulate the corrosion rate data of the anchor rod from the salt spray environment, rain and wet environment, and original rock seepage corrosion environment. Therefore, a combined stress loading anchor rod rapid corrosion device and test method are proposed. Therefore, the existing technology urgently needs to be further improved. Summary of the invention

[0005] In view of the shortcomings of the above-mentioned prior art, one purpose of the present invention is to propose a combined stress loading anchor rapid corrosion device to solve the problem that the directional stress data and corrosion environment simulation data applied during the test of the existing multi-anchor corrosion test device and method for applying prestress in the above-mentioned background technology are relatively single, making it difficult to ensure the accuracy of the anchor corrosion rate data.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: A combined stress-loaded anchor rapid corrosion device comprises a base, a test box, a vertical plate, a servo hydraulic station, an axial force loading unit, a radial force loading unit, a salt spray generator and a controller. The test box is fixedly installed above the base, the vertical plate is vertically arranged on the left side of the test box, and its lower end is fixedly connected to the base as a whole. The servo hydraulic station is arranged on the left side of the vertical plate.

[0007] The test box is a square box with a top cover. The interior of the test box has three independent chambers arranged from front to back, namely the first chamber, the second chamber and the third chamber. An axial force loading unit is provided on the left side wall of each chamber through a first guide sleeve, and a radial force loading unit is provided at the center of the bottom through a second guide sleeve.

[0008] An anchor rod limiting mechanism is provided on the right side wall of each chamber, which is directly opposite to the axial force loading unit. The axial force loading unit and the anchor rod limiting mechanism position the two ends of the anchor rod specimen located in the chamber. Each chamber is equipped with an electro-corrosion generating component, which includes a DC power supply and an electrode sheet with a wiring terminal.

[0009] The right side of the vertical plate is provided with a first servo cylinder with the same number and one-to-one corresponding position as the axial force loading units, and the bottom of the test box is provided with a second servo cylinder with the same number and one-to-one corresponding position as the radial force loading units, and the servo hydraulic station independently supplies oil and returns oil to each servo cylinder.

[0010] In the working state, the first servo cylinder applies an axial force to the anchor specimen through the corresponding axial force loading unit, and the second servo cylinder applies a radial force to the anchor specimen through the corresponding radial force loading unit.

[0011] A ceramic heating plate is fixedly embedded in the bottom of each chamber, a temperature and humidity monitor is provided on the side wall of the test box, the salt spray generator is arranged outside the test box, connected to the salt spray port on the side wall of the first chamber through a pipeline and supplied with atomized corrosive medium, a corrosive medium concentration sensor is provided on the upper side wall of the first chamber, and a liquid collecting tank is provided at the bottom.

[0012] A drip mechanism is provided inside the second chamber, which is connected to a water supply device pipeline arranged outside the test box. A water inlet and a drain are respectively provided on the left and right walls of the third chamber. The third chamber forms a water supply circulation system with an external water storage tank through its water inlet and drain.

[0013] Furthermore, the base and the vertical plate are both square flat plates, the four corners of the bottom of the test box are fixedly connected to the base through a column respectively, and the left side wall is fixedly connected to the vertical plate through four regularly arranged cross bars.

[0014] Furthermore, there are two vertically arranged and parallelly spaced partitions inside the test chamber. The bottom, left and right sides of the partitions are integrally fixed to the inner wall of the test chamber, and the upper end surfaces thereof are at the same height as the top of the test chamber.

[0015] The top cover is made of transparent plexiglass or acrylic material. A "mesh" - shaped sealing piece is fixedly embedded at the top of the test chamber. The top cover is detachably fixed to the top of the test chamber to enclose the three chambers inside.

[0016] Furthermore, the first guiding sleeve is horizontally and fixedly embedded on the left side wall of the test chamber, and the second guiding sleeve is vertically and fixedly embedded on the bottom plate of the test chamber.

[0017] Both ends of the first and second guiding sleeves are respectively located inside and outside the test chamber, and the inside of the first and second guiding sleeves is a tunnel cavity with a circular cross - section.

[0018] Furthermore, the axial force loading unit includes an anchor rod positioning seat and an axial force monitoring mechanism. The anchor rod positioning seat is a cylindrical structure, slidably arranged inside the first guiding sleeve. A first O - ring seal is fixedly sleeved on the circumferential outer wall of the anchor rod positioning seat in an embedded manner, and the anchor rod positioning seat is in transverse sliding and sealing cooperation with the inner wall of the first guiding sleeve.

[0019] A circular groove matching the end of the anchor rod specimen is formed at the right end of the anchor rod positioning seat. The axial force monitoring mechanism is installed at the left end of the anchor rod positioning seat. The piston rod of the first servo - cylinder drives the anchor rod positioning seat to move transversely through the axial force monitoring mechanism.

[0020] Furthermore, the axial force monitoring mechanism includes a first pressure sensor, a first pressure contact piece and a first linear guiding component. The first pressure sensor is fixed at the center position of the left end face of the anchor rod positioning seat. The first pressure contact piece is located on the left side of the first pressure sensor, adjacent to the stress - sensing end of the first pressure sensor.

[0021] Both sides of the first pressure contact piece are movably connected to the left end of the anchor rod positioning seat through two first linear guiding components symmetrically arranged with respect to the first pressure sensor.

[0022] The first linear guiding component includes a first guide rod, a first sleeve and a first return spring. The first sleeve is horizontally arranged. Its right end is fixedly connected to the left end face of the anchor rod positioning seat. The left end of the first guide rod is fixedly connected to the first pressure contact piece, and its right end is inserted into and slidably matched with the first sleeve. The first return spring is arranged inside the first sleeve and is on the right side of the first guide rod.

[0023] Furthermore, the anchor rod limiting mechanism includes a positioning plate, an arc-shaped limiting plate and a gear drive assembly. The positioning plate is a disc-shaped structure and is vertically fixed on the right side wall of the chamber in which it is located. A circular cavity is opened at the center of the positioning plate, and three long slide grooves are provided on its left side wall. The three long slide grooves are evenly distributed on a circle with the center of the positioning plate as the center.

[0024] A lead screw and a nut seat are provided on the inner side of each of the long slide grooves. The nut seat and the inner wall of the corresponding long slide groove are slidably matched along the normal direction of the positioning plate. One end of the lead screw is rotationally matched with the side wall of the long slide groove, and the other end extends to the inner side of the circular cavity. The lead screw is passed through the inner side of the nut seat and is threadedly matched with it.

[0025] The left side of the positioning plate has arc-shaped limit plates, the number of which is equal to that of the nut seats and the positions of which are one-to-one corresponding to each other. The middle part of each arc-shaped limit plate is fixedly connected to the corresponding nut seat, and the electrode sheet is fixed on the outer wall of one of the arc-shaped limit plates.

[0026] The gear drive assembly includes a central bevel gear and three driven bevel gears. The central bevel gear is located at the center of the circular cavity. The end of its gear shaft passes through the right side wall of the test box and is provided with an open locking block. The three driven bevel gears are respectively installed at the other ends of the three lead screws and are all meshed with the central bevel gear. The central bevel gear drives the three arc-shaped limit plates to move synchronously and in the same direction along the normal direction of the positioning plate through the lead screw.

[0027] Furthermore, the axial force loading unit includes a force transmission rod and a radial force monitoring mechanism. The force transmission rod is arranged vertically, a cylindrical sliding seat is fixed to the lower end of the force transmission rod, and a loading end is fixedly connected to the upper end of the force transmission rod.

[0028] The circumferential outer wall of the sliding seat is fixedly sleeved with a second O-ring in an embedded manner. The sliding seat is located on the inner side of the second guide sleeve and vertically slides and seals with the inner wall of the tunnel cavity of the second guide sleeve.

[0029] The radial force monitoring mechanism includes a second pressure sensor, a second pressure contact piece and a second linear guide assembly. The second pressure sensor is fixed at the center position of the bottom of the sliding seat. The second pressure contact piece is located below the second pressure sensor and is arranged adjacent to the stress sensing end of the second pressure sensor.

[0030] There are two second linear guide assemblies and they are symmetrically arranged on both sides of the second pressure sensor. The first linear guide assembly includes a second guide rod, a second sleeve and a second return spring. The second sleeve is arranged vertically, and its upper end is fixedly connected to the bottom of the sliding seat. The second return spring is arranged inside the second sleeve. The lower end of the second guide rod is fixedly connected to the second pressure contact piece, and its upper end is passed through the second sleeve and vertically slidably matched.

[0031] Furthermore, the dripping mechanism includes a dripping pipe, which is horizontally arranged directly above the anchor specimen in the second chamber, and has a plurality of dripping nozzles at equal intervals along its length at its bottom. The water inlet end of the dripping pipe is located outside the test box and is equipped with a flow regulating valve, which is connected to the water source through a water supply pipe.

[0032] A heat-sensitive probe and a humidity-sensitive probe are installed on the side wall of the upper part of each chamber, and all the heat-sensitive probes and humidity-sensitive probes are respectively connected to the temperature and humidity monitor for communication.

[0033] Another object of the present invention is to provide a method for rapid corrosion testing of anchor rods.

[0034] A method for testing rapid corrosion of anchor rods is based on the above-mentioned combined stress loading rapid corrosion device of anchor rods. The method comprises the following steps: S1. Make three anchor rod specimens of the same specifications and length, and grind the two end faces of each anchor rod specimen to make them smooth. Install the three anchor rod specimens into the first chamber, the second chamber, and the third chamber respectively, and lay gravel and fine sand on the bottom of the third chamber.

[0035] When the anchor rod specimen is installed in the corresponding chamber, the left end of the anchor rod specimen is plugged into the corresponding axial force loading unit, and the right end is fixedly connected to the side wall of the test box through the corresponding anchor rod limiting mechanism.

[0036] S2. Connect the left end of each anchor specimen to the positive pole of the corresponding DC power supply through a wire, connect the negative pole of the DC power supply to the electrode sheet at the right end of the anchor specimen through another wire, and connect a sliding rheostat and a switch in series in the circuit.

[0037] S3, connecting the salt spray port on the side wall of the first chamber to the outlet pipeline of the salt spray generator, and filling the salt spray generator with the prepared corrosive medium salt solution.

[0038] The water inlet of the drip mechanism is connected to the water supply device pipeline, and the water inlet and outlet of the third chamber are connected to the external water storage tank to form a water supply circulation system. After that, the top cover is fixed to the top of the test box to close the first chamber, the second chamber and the third chamber.

[0039] S4, the servo hydraulic station is started, and the piston rod of each first servo oil cylinder applies an axial force to the corresponding anchor specimen through the axial force loading unit. When the first pressure sensor of the axial force loading unit detects that the axial force reaches the set value, the loading is stopped.

[0040] The piston rod of each second servo cylinder applies a radial force to the middle of the corresponding anchor rod specimen through a radial force loading unit. When the second pressure sensor of the radial force loading unit detects that the radial force reaches a set value, loading is stopped.

[0041] S5. The salt spray generator starts to work and continuously supplies atomized corrosive medium into the first chamber through the salt spray port.

[0042] The water supply device supplies water to the dripping mechanism, and the dripping mechanism continuously drips water to the surface of the anchor rod specimen in the second chamber through the dripping nozzle at the bottom thereof.

[0043] The water supply circulation system injects water into the third chamber through the water inlet. After the water surface covers the anchor rod specimen in the third chamber, the drain outlet of the third chamber is opened to keep the water surface at a constant height.

[0044] S6. The ceramic heating plates in the three chambers all start working, and the temperature and humidity monitors monitor the temperature and humidity values ​​of each chamber respectively. When the temperature of each chamber reaches the set value, the start time of the test begins to be recorded. The temperature of each chamber is within the set temperature range.

[0045] During the test, when the first pressure sensor detects that the change in the axial force reaches 0.1% of its original set value, the first servo cylinder readjusts the axial force of the anchor specimen to its original set value.

[0046] When the second pressure sensor detects that the change in the radial force reaches 0.1% of its original set value, the second servo cylinder readjusts the radial force of the anchor specimen to its original set value.

[0047] The accumulated liquid at the bottom of the first chamber and the second chamber is drained periodically.

[0048] S7. At the end of the test cycle, the ceramic heating plate stops working, the salt spray generator, water supply device and water supply circulation system are turned off, and the liquid in the three chambers is drained.

[0049] The top cover of the test box was removed, and the three anchor specimens were taken out from the test box respectively, and the mechanical properties of each anchor specimen were tested.

[0050] By adopting the above technical solution, the beneficial technical effects of the present invention are: 1. The interior of the test box of the present invention is divided into three independent test chambers, namely the first chamber, the second chamber and the third chamber, which can simultaneously carry out salt spray, rain, immersion and simulated original rock corrosion tests, greatly improving the test efficiency. A temperature and humidity monitor is installed on the side wall of the test box, and the heating plate at the bottom of the box is used for heating, which is convenient for adjusting the temperature and humidity data in the box and improving the accuracy of the environmental simulation data. At the same time, an external current is applied to the anchor rod sample during each test process, thereby accelerating the corrosion rate and improving the corrosion test efficiency.

[0051] 2. The present invention is equipped with a corrosion medium concentration sensor and a liquid collecting tank in the salt spray test chamber, which can monitor the salt spray concentration data in real time, and perform chemical analysis on the droplets formed by the liquefaction of the collected salt spray to obtain the specific corrosion status data of the anchor rod at different time periods, thereby further improving the accuracy and reference of the salt spray corrosion test data.

[0052] 3. The servo hydraulic device of the present invention provides axial force and radial force to the anchor rod, and uses the first pressure sensor and the second pressure sensor to monitor the stress change of the anchor rod specimen in real time and balance the stress change caused by the corrosion of the anchor rod in time, and ensure that the force of the anchor rod specimen is constant during the test. The second servo cylinder applies lateral force to the anchor rod specimen through the loading end of the force transmission rod. The loading end can be detached and replaced. By replacing different ends, different combined stresses are simulated to ensure the rigor of the test process and improve the accuracy of the test data. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a three-dimensional structural schematic diagram of a combined stress-loaded anchor rapid corrosion device of the present invention.

[0054] Figure 2 It is a front view of a combined stress-loaded anchor rapid corrosion device of the present invention.

[0055] Figure 3 It is a top view of a combined stress-loaded anchor rapid corrosion device of the present invention.

[0056] Figure 4 It is a partial exploded view of the combination of the first guide sleeve and the axial force loading unit of the present invention.

[0057] Figure 5 It is a structural schematic diagram of the axial force monitoring mechanism of the present invention.

[0058] Figure 6 A partial cross-sectional view of the combination of the second guide sleeve and the radial force loading unit of the present invention.

[0059] Figure 7 yes Figure 6 A partial enlarged view of part A.

[0060] Figure 8 It is a cross-sectional view of the test box of the present invention.

[0061] Fig. 9 It is a schematic diagram of the structural principle of the anchor rod limiting mechanism of the present invention.

[0062] Fig.10 It is a schematic diagram of the working state of a combined stress-loaded anchor rapid corrosion device of the present invention.

[0063] As shown in the figure: 1. base; 11. upright plate; 12. upright column; 13. cross bar; 2. test box; 21. top cover; 22. partition; 23. first guide sleeve; 24. second guide sleeve; 25. sealing sheet; 201. first chamber; 2011. liquid collecting tank; 202. second chamber; 203. third chamber; 3. servo hydraulic station; 31. first servo cylinder; 32. second servo cylinder; 4. salt spray generator; 41. corrosive medium concentration sensor; 42. salt spray port; 51. anchor rod positioning seat; 511. first O-ring; 52. first pressure sensor; 53. first pressure contact sheet; 54. first guide rod; 55. first sleeve; 56. first return spring; 57 , first mounting seat; 61, positioning plate; 611, circular cavity; 612, long slide groove; 62, arc limit plate; 63, lead screw; 64, nut seat; 65, center bevel gear; 66, driven bevel gear; 67, open locking block; 71, force transmission rod; 711, loading end; 72, sliding seat; 721, second O-ring; 73, second pressure sensor; 74, second pressure contact piece; 75, second guide rod; 76, second sleeve; 77, second return spring; 78, second mounting seat; 81, ceramic heating plate; 82, temperature and humidity monitor; 83, dripping pipe; 84, water inlet; 85, drain outlet; 86, circulation pump, drain outlet; 9, anchor rod specimen; 91, electrode sheet. DETAILED DESCRIPTION

[0064] In order to make the advantages and technical solutions of the present invention more clear and explicit, the present invention is described in detail below in conjunction with specific embodiments.

[0065] Embodiment 1, combination Figures 1 to 5 A combined stress-loaded anchor rapid corrosion device comprises a base 1, a test box 2, a vertical plate 11, a servo hydraulic station 3, an axial force loading unit, a radial force loading unit, a salt spray generator 4 and a controller. The base 1 and the vertical plate 11 are both square flat plates. The test box 2 is fixedly installed above the base 1. Specifically, the four corners of the bottom of the test box 2 are fixedly connected to the base 1 through a column 12 to form a whole.

[0066] The vertical plate 11 is arranged vertically on the left side of the test box 2, and its lower end is fixedly connected to the base 1 as a whole. The servo hydraulic station 3 is installed on the left side wall of the vertical plate 11, and the oil pump signal end of the servo hydraulic station 3 is communicated with the controller. According to the signal instructions of the controller, pressurized oil is provided to each first servo cylinder 31 and each second servo cylinder 32 respectively, and the direction, pressure and flow of the oil are controlled to apply axial force and radial force to the anchor specimen 9.

[0067] The left side wall of the test box 2 is fixedly connected to the vertical plate 11 through four regularly arranged cross bars 13, so that the test box 2 can be firmly fixed to the vertical plate 11 and the base 1, and will not be displaced or deformed under the action of external force. The test box 2 is a square box body equipped with a top cover 21. The interior of the test box 2 has three independent chambers arranged from front to back, namely the first chamber 201, the second chamber 202 and the third chamber 203. The interior of the test box 2 has two partitions 22 arranged vertically and parallel to each other. The bottom and left and right sides of the partition 22 are fixed to the inner wall of the test box 2 as a whole, and the upper end surface of the partition 22 is consistent with the top height of the test box 2.

[0068] Specifically, the top cover 21 is made of transparent organic glass or acrylic material, and a photographic device can be placed above the top cover 21 to record the corrosion process of the anchor rod specimen 9. A "mesh"-shaped sealing sheet 25 is fixed on the top of the test box 2 in an embedded manner. The sealing sheet 25 is made of elastic rubber material, and its upper surface is slightly higher than the upper surface of the test box 2. The top cover 21 is fixed to the top of the test box 2 by screws, and the three independent chambers inside it are all closed.

[0069] An axial force loading unit is provided on the left side wall of each chamber via a first guide sleeve 23 , and a radial force loading unit is provided at the bottom center thereof via a second guide sleeve 24 .

[0070] Specifically, the first guide sleeve 23 is fixedly embedded in the left side wall of the test box 2 in a transverse direction, and the circumferential outer wall of the first guide sleeve 23 is fixedly sealed and welded to the left side plate of the test box 2. The second guide sleeve 24 is fixedly embedded in the bottom plate of the test box 2 in a vertical direction, and the circumferential outer wall of the second guide sleeve 24 is fixedly sealed and welded to the bottom plate of the test box 2. Both ends of the first guide sleeve 23 and the second guide sleeve 24 are respectively located at the inner side and the outer side of the test box 2, and the interior of the first guide sleeve 23 and the second guide sleeve 24 is a tunnel cavity with a circular cross section.

[0071] The axial force loading unit includes an anchor rod positioning seat 51 and an axial force monitoring mechanism. The anchor rod positioning seat 51 is a cylindrical structure. The anchor rod positioning seat 51 is slidably arranged on the inner side of the first guide sleeve 23. The anchor rod positioning seat 51 and the first guide sleeve 23 remain coaxial. The circumferential outer wall of the anchor rod positioning seat 51 is fixedly sleeved with a first O-ring 511 in an embedded manner. The anchor rod positioning seat 51 and the inner wall of the first guide sleeve 23 are laterally slidably sealed.

[0072] The right end of the anchor rod positioning seat 51 is provided with a hole that matches the end of the anchor rod specimen, and the axial force monitoring mechanism is installed at the left end of the anchor rod positioning seat 51. The piston rod of the first servo oil cylinder 31 drives the anchor rod positioning seat 51 to move horizontally through the axial force monitoring mechanism. In the use state, the left end of the anchor rod specimen 9 is placed in the circular groove at the right end of the anchor rod positioning seat 51, and the anchor rod positioning seat 51 supports and positions the left end of the anchor rod specimen 9.

[0073] Specifically, the axial force monitoring mechanism includes a first pressure sensor 52, a first pressure contact piece 53 and a first linear guide assembly. The first pressure sensor 52 is fixed to the center position of the left end surface of the anchor rod positioning seat 51 through a first mounting seat 57. The first pressure contact piece 53 is located on the left side of the first pressure sensor 52 and is arranged adjacent to the stress sensing end of the first pressure sensor 52. The signal end of the first pressure sensor 52 is connected to the controller for communication and sends data to the controller.

[0074] Both sides of the first pressure contact piece 53 are movably connected to the left end of the anchor rod positioning seat 51 through two first linear guide components symmetrically arranged with respect to the first pressure sensor 52 .

[0075] The first linear guide assembly includes a first guide rod 54, a first sleeve 55 and a first return spring 56. The first sleeve 55 is arranged horizontally in a transverse line, and its right end is fixedly connected to the left end surface of the anchor rod positioning seat 51. The left end of the first guide rod 54 is fixedly connected to the first pressure contact piece 53, and its right end is plugged and slidably matched with the first sleeve 55. The first return spring 56 is arranged inside the first sleeve 55 and is on the right side of the first guide rod 54.

[0076] After the piston rod end of the first servo cylinder 31 contacts the first pressure contact piece 53, the first pressure contact piece 53 is driven to move rightward and contact and compress the stress sensing end of the first pressure sensor 52. At the same time, the first pressure contact piece 53 is driven to apply a force to the anchor rod positioning seat 51 through the first linear guide assembly, and an axial force is applied to the anchor rod specimen 9 installed in the corresponding chamber through the anchor rod positioning seat 51. The first pressure sensor 52 monitors the value of the axial force in real time. When the axial force reaches the set value, the piston rod of the first servo cylinder 31 stops moving to keep the axial force on the anchor rod specimen 9 constant.

[0077] An anchor rod limiting mechanism directly facing the axial force loading unit is provided on the right side wall of each chamber. The axial force loading unit and the anchor rod limiting mechanism position the two ends of the anchor rod specimen located in the chamber.

[0078] The right side of the vertical plate 11 is provided with a first servo oil cylinder 31 with the same number and one-to-one corresponding position as the axial force loading unit, and the lower part of the test box 2 is provided with a second servo oil cylinder 32 with the same number and one-to-one corresponding position as the radial force loading unit, and the servo hydraulic station 3 supplies oil and returns oil to each servo oil cylinder independently. In the working state, the first servo oil cylinder 31 applies an axial force to the anchor rod specimen through the corresponding axial force loading unit, and the second servo oil cylinder 32 applies a radial force to the anchor rod specimen through the corresponding radial force loading unit.

[0079] Specifically, the anchor rod limiting mechanism includes a positioning plate 61, an arc-shaped limiting plate 62 and a gear drive assembly. The positioning plate 61 is a disc-shaped structure and is vertically fixed on the right side wall of the chamber where it is located. The positioning plate 61 is relatively coaxially arranged with the first guide sleeve 23 in the same chamber. A circular cavity 611 is provided at the center of the positioning plate 61, and three long slide grooves 612 are provided on the left side wall of the positioning plate 61. The three long slide grooves 612 are evenly distributed on the circumference with the center of the positioning plate 61 as the center, and the length direction is arranged along the normal direction of the positioning plate 61.

[0080] A lead screw 63 and a nut seat 64 are provided on the inner side of each of the long slide grooves 612. The nut seat 64 slides with the inner wall of the corresponding long slide groove 612 along the normal direction of the positioning plate 61. One end of the lead screw 63 rotates with the side wall of the long slide groove 612, and the other end extends to the inner side of the circular cavity 611. The lead screw 63 is passed through the inner side of the nut seat 64 and is threadedly engaged with it.

[0081] The left side of the positioning plate 61 is provided with the arc-shaped limiting plates 62 whose number is equal to the nut seats 64 and whose positions correspond one to one. The middle part of each arc-shaped limiting plate 62 is fixedly connected to the corresponding nut seat 64 .

[0082] The gear drive assembly includes a central bevel gear 65 and three driven bevel gears 66. The central bevel gear 65 is located at the center of the circular cavity 611. The end of the gear shaft of the central bevel gear 65 passes through the right side wall of the test box 2 and is provided with an open locking block 67. The open locking block 67 is fixed to the right side outer wall of the test box 2 and is provided with a bolt assembly. The end of the gear shaft of the central bevel gear 65 has a hexagonal end, and the central bevel gear 65 can be rotated using a wrench.

[0083] The three driven bevel gears 66 are respectively installed at the other end of the three lead screws 63, and are all meshed with the central bevel gear 65. The central bevel gear 65 drives the three arc-shaped limit plates 62 to move synchronously and in the same direction along the normal direction of the positioning disk 61 through the lead screw 63. When installing the anchor rod specimen 9, the three arc-shaped limit plates 62 are in an expanded state by rotating the central bevel gear 65. First, the left end of the anchor rod specimen 9 is inserted into the inner side of the anchor rod positioning seat 51, and then the right end of the anchor rod specimen 9 is placed between the three arc-shaped limit plates 62. The first reset spring 56 causes the right end of the anchor rod specimen 9 to support the left side wall of the positioning disk 61. After that, the central bevel gear 65 is rotated in the opposite direction to cause the three arc-shaped limit plates 62 to shrink inward at the same time, align the position and clamp the right end of the anchor rod specimen 9, and complete the installation process of the anchor rod specimen 9.

[0084] Each chamber is equipped with an electro-corrosion generating assembly, which includes a DC power supply and an electrode sheet 91 with a terminal, and the electrode sheet 91 is fixed on the outer wall of one of the arc-shaped limiting plates 62 of the anchor rod limiting mechanism. The DC power supply adopts a DC power supply with a voltage of 5V and a current of 3A, and is equipped with a sliding rheostat and a switch. After the anchor rod specimen 9 is installed, the positive electrode of the DC power supply is connected to the left end of the corresponding anchor rod specimen 9 through a wire, and its negative electrode is connected to the terminal of the electrode sheet 91 through another wire. The sliding rheostat and the switch are connected in series to the wire between the negative electrode of the DC power supply and the electrode sheet 91, simulating the process of electrons flowing on the anchor rod specimen to accelerate the corrosion rate.

[0085] Specifically, the radial force loading unit includes a force transmission rod 71 and a radial force monitoring mechanism. The force transmission rod 71 is arranged vertically, and a cylindrical sliding seat 72 is fixed at the lower end of the force transmission rod 71, and a loading terminal 711 is fixedly connected at the upper end thereof. A second O-ring 721 is fixedly sleeved on the circumferential outer wall of the sliding seat 72 in an embedded manner. The sliding seat 72 is located on the inner side of the second guide sleeve 24 and vertically slides and seals with the inner wall of the tunnel cavity of the second guide sleeve 24.

[0086] The radial force monitoring mechanism includes a second pressure sensor 73, a second pressure contact piece 74 and a second linear guide assembly. The second pressure sensor 73 is fixed to the center of the bottom of the sliding seat 72 through a second mounting seat 78. The second pressure contact piece 74 is located below the second pressure sensor 73 and is arranged adjacent to the stress sensing end of the second pressure sensor 73. The signal end of the second pressure sensor 73 is connected to the controller for communication and sends data to the controller.

[0087] There are two second linear guide assemblies which are symmetrically arranged on both sides of the second pressure sensor 73. The first linear guide assembly includes a second guide rod 75, a second sleeve 76 and a second return spring 77. The second sleeve 76 is arranged vertically, and its upper end is fixedly connected to the bottom of the sliding seat 72. The second return spring 77 is arranged inside the second sleeve 76. The lower end of the second guide rod 75 is fixedly connected to the second pressure contact piece 74, and its upper end is passed through the second sleeve 76 and vertically slides with it.

[0088] After the piston rod end of the second servo cylinder 32 contacts the second pressure contact piece 74, the second pressure contact piece 74 is driven to move upward and contact and compress the stress sensing end of the second pressure sensor 73. At the same time, the second pressure contact piece 74 is driven to move the sliding seat 72 upward through the second linear guide assembly, and a radial force is applied to the middle part of the anchor specimen 9 installed in the corresponding chamber through the force transmission rod 71. The second pressure sensor 73 monitors the value of the radial force in real time. When the radial force reaches the set value, the piston rod of the second servo cylinder 32 stops moving to keep the radial force on the anchor specimen 9 constant.

[0089] A ceramic heating plate 81 is fixedly embedded at the bottom of each chamber, and the ceramic heating plate 81 is connected to an external power supply to heat the interior of the chamber in which it is located. A temperature and humidity monitor 82 is provided on the side wall of the test box 2, and a thermistor and a humidity probe are installed on the upper side wall of each chamber. All the thermistor probes and humidity probes are respectively connected to the temperature and humidity monitor 82 for communication, and the signal end of the temperature and humidity monitor 82 is connected to the controller for communication. The temperature and humidity monitor 82 displays the temperature and humidity values ​​of each chamber in real time. The controller controls the working state of the ceramic heating plate 81 through instructions to control the temperature of each chamber within the set range.

[0090] The salt spray generator 4 is arranged outside the test box and is connected to the salt spray port 42 on the side wall of the first chamber 201 through a pipeline. The salt spray port 42 on the side wall of the first chamber 201 supplies the corrosive medium in atomized state into the interior thereof. The upper side wall of the first chamber 201 is provided with a corrosive medium concentration sensor 41, and the corrosive medium concentration sensor 41 can monitor the salt spray concentration data in real time. The bottom of the first chamber 201 is provided with a liquid collecting tank 2011, and the bottom of the liquid collecting tank 2011 is provided with a drain pipe with a valve. The accumulated liquid in the liquid collecting tank 2011 is regularly discharged and collected through the drain pipe. Chemical analysis is performed on the droplets formed by the liquefaction of the collected salt spray to obtain specific corrosion state data of the anchor rod at different time periods, so as to further improve the accuracy and reference of the salt spray corrosion test data.

[0091] The second chamber 202 is provided with a drip mechanism inside, and the drip mechanism is connected to the water supply device pipeline arranged outside the test box. Specifically, the drip mechanism includes a drip pipe 83, which is horizontally arranged just above the anchor rod specimen in the second chamber 202, and has a plurality of drip nozzles at equal intervals along its length at its bottom. The water inlet end of the drip pipe 83 is located outside the test box 2 and is equipped with a flow regulating valve, which is connected to the water source through a water supply pipe. The drip nozzle performs dripping treatment on the anchor rod specimen 9, thereby simulating the rain corrosion environment of the underground anchor rod when it is dripping with groundwater.

[0092] In addition, a drain pipe with a valve is provided at the bottom of the second chamber 202, and the water accumulated in the lower part of the second chamber 202 is regularly drained through the drain pipe.

[0093] The third chamber 203 is provided with a water inlet 84 and a water outlet 85 on the left and right walls, respectively. The third chamber 203 forms a water supply circulation system with an external water storage tank through its water inlet 84 and water outlet 85. A circulation pump 86 is arranged at the water inlet 84 of the water supply circulation system. The third chamber 203 is used to conduct water immersion simulation corrosion or original rock seepage corrosion test on the anchor specimen. Specifically, water is continuously injected into the third chamber 203 through the circulation pump 86 to simulate the water immersion environment; or the inner side of the third chamber 203 is filled with medium such as gravel and fine sand, and then the circulation pump 86 continuously injects pressurized corrosion solution into the third chamber 203 through the water inlet 84, and the corrosion solution flows through the anchor specimen 9 in a flowing state, thereby simulating the original rock seepage corrosion test.

[0094] Embodiment 2, combined Figures 1 to 7 A method for testing the rapid corrosion of anchor rods is provided. The method is based on the above-mentioned combined stress loading rapid corrosion device for anchor rods. The method comprises the following steps: S1. Make three anchor specimens 9 of the same specification and equal length, and grind the two end faces of each anchor specimen 9 to make them smooth. Install the three anchor specimens 9 into the first chamber 201, the second chamber 202 and the third chamber 203 respectively, and lay gravel and fine sand on the bottom of the third chamber 203.

[0095] When the anchor rod specimen 9 is installed in the corresponding chamber, the left end of the anchor rod specimen 9 is plugged into the corresponding axial force loading unit, and the right end is fixedly connected to the side wall of the test box 2 through the corresponding anchor rod limiting mechanism.

[0096] S2. Connect the left end of each anchor specimen 9 to the positive electrode of the corresponding DC power supply through a wire, connect the negative electrode of the DC power supply to the electrode sheet 91 at the right end of the anchor specimen 9 through another wire, and connect a sliding rheostat and a switch in series in the circuit.

[0097] S3, connecting the salt mist port 42 on the side wall of the first chamber 201 to the outlet pipe of the salt mist generator 4, and filling the salt mist generator 4 with the prepared corrosive medium salt solution.

[0098] The water inlet end of the drip mechanism is connected to the water supply device pipeline, and the water inlet 84 and the outlet 85 of the third chamber 203 are connected to the external water tank to form a water supply circulation system. After that, the top cover 21 is fixedly installed on the top of the test box 2 to close the first chamber 201, the second chamber 202 and the third chamber 203.

[0099] S4, the servo hydraulic station is started, and the piston rod of each first servo oil cylinder 31 applies an axial force to the corresponding anchor specimen 9 through the axial force loading unit. When the first pressure sensor 52 of the axial force loading unit detects that the axial force reaches the set value, the loading is stopped.

[0100] The piston rod of each second servo cylinder 32 applies a radial force to the middle of the corresponding anchor specimen 9 through the radial force loading unit. When the second pressure sensor 73 of the radial force loading unit detects that the radial force reaches a set value, the loading is stopped.

[0101] S5 , the salt mist generator 4 starts to work, and continuously supplies the corrosive medium in atomized state into the first chamber 201 through the salt mist port 42 .

[0102] The water supply device supplies water to the dripping mechanism, and the dripping mechanism continuously drips water onto the surface of the anchor rod specimen 9 in the second chamber 202 through the dripping nozzle at the bottom thereof.

[0103] The water supply circulation system injects water or a corrosive solution with a certain pressure into the third chamber 203 through the water inlet 84. After the liquid level is above the anchor specimen 9 in the third chamber 203, the drain port of the third chamber 203 is opened, and the water level in the third chamber 203 is kept at a constant height.

[0104] S6. The ceramic heating plates 81 in the three chambers are powered on and start working. The temperature and humidity monitor 82 monitors the temperature and humidity of each chamber respectively. When the temperature of each chamber reaches the set value, the start time of the test is recorded. The temperature of each chamber is within the set temperature range.

[0105] During the test, when the first pressure sensor 52 detects that the change in the axial force reaches 0.1% of its original set value, the first servo cylinder 31 readjusts the axial force of the anchor specimen 9 to its original set value.

[0106] When the second pressure sensor 73 detects that the change in the radial force reaches 0.1% of its original set value, the second servo cylinder 32 readjusts the radial force of the anchor specimen 9 to its original set value.

[0107] The accumulated liquid at the bottom of the first chamber 201 and the second chamber 202 is drained periodically.

[0108] S7. At the end of the test cycle, the ceramic heating plate 81 stops working, the salt spray generator 4, the water supply device and the water supply circulation system are turned off, and the liquids in the three chambers are drained.

[0109] The top cover 21 of the test box 2 is removed, and the three anchor rod specimens 9 are taken out from the inside of the test box 2 respectively, and the mechanical properties of each anchor rod specimen 9 are tested.

[0110] Parts not described in the present invention can be implemented by adopting or drawing on existing technologies.

[0111] Furthermore, the terms “first” and “second” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0112] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0113] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A combined stress loading anchor rapid corrosion device, characterized in that: It includes a base, a test chamber, a vertical plate, a servo hydraulic station, an axial force loading unit, a radial force loading unit, a salt spray generator and a controller. The test chamber is fixedly installed above the base. The vertical plate is vertically arranged on the left side of the test chamber, and its lower end is fixedly connected to the base as a whole. The servo hydraulic station is arranged on the left side of the vertical plate; The test chamber is a square box body equipped with a top cover. Inside the test chamber, there are three independent chambers arranged in sequence from front to back, namely the first chamber, the second chamber and the third chamber. One of the axial force loading units is provided on the left side wall of each chamber through a first guiding sleeve, and one of the radial force loading units is provided at the center of the bottom of each chamber through a second guiding sleeve; On the right side wall of each chamber, there is a bolt limiting mechanism facing the axial force loading unit. The axial force loading unit and the bolt limiting mechanism position the two ends of the bolt specimen located in this chamber. Each chamber is equipped with an electric corrosion generating component, and the electric corrosion generating component includes a DC power supply and an electrode plate with a terminal; On the right side of the vertical plate, there are first servo cylinders equal in number and corresponding in position to the axial force loading units. Below the test chamber, there are second servo cylinders equal in number and corresponding in position to the radial force loading units. The servo hydraulic station supplies oil and returns oil independently to each servo cylinder; In the working state, the first servo cylinder applies an axial force to the bolt specimen through the corresponding axial force loading unit, and the second servo cylinder applies a radial force to the bolt specimen through the corresponding radial force loading unit; At the bottom of each chamber, a ceramic heating sheet is fixedly embedded. A temperature and humidity monitor is provided on the side wall of the test chamber. The salt spray generator is arranged outside the test chamber and is connected to the salt spray port on the side wall of the first chamber through a pipeline to supply atomized corrosive medium. On the upper side wall of the first chamber, there is a corrosive medium concentration sensor, and there is a liquid collecting tank at its bottom; Inside the second chamber, there is a drip irrigation mechanism, and the drip irrigation mechanism is connected to a water supply device arranged outside the test chamber through a pipeline. On the left and right side walls of the third chamber, there are a water inlet and a drain outlet respectively. The third chamber and an external water storage tank form a water supply circulation system through its water inlet and drain outlet; 2. The combined stress loading anchor rapid corrosion device according to claim 1 is characterized in that: Both the base and the vertical plate are square flat plates. The four corners of the bottom of the test chamber are respectively fixedly connected to the base as a whole through a column, and its left side wall is fixedly connected to the vertical plate through four regularly arranged cross bars; 3. The combined stress loading anchor rapid corrosion device according to claim 1 is characterized in that: Inside the test chamber, there are two vertical partitions arranged in parallel at intervals. The bottom, left and right sides of the partitions are fixedly integrated with the inner wall of the test chamber, and the upper end surface of the partitions is at the same height as the top of the test chamber; The top cover is made of transparent plexiglass or acrylic material. On the top of the test chamber, a "mesh" shaped sealing piece is fixedly embedded. The top cover is detachably fixed on the top of the test chamber to enclose the three chambers inside; 4. The combined stress loading anchor rapid corrosion device according to claim 1 is characterized in that: The first guiding sleeve is horizontally and fixedly embedded on the left side wall of the test chamber, and the second guiding sleeve is vertically and fixedly embedded on the bottom plate of the test chamber; Both ends of the first and second guiding sleeves are respectively located inside and outside the test chamber. The inside of the first and second guiding sleeves is a tunnel cavity with a circular cross-section.

5. The combined stress loading anchor rapid corrosion device according to claim 4 is characterized in that: The axial force loading unit includes an anchor rod positioning seat and an axial force monitoring mechanism. The anchor rod positioning seat is a cylindrical structure and is slidably arranged on the inner side of the first guide sleeve. The outer circumferential wall of the anchor rod positioning seat is fixedly sleeved with a first O-ring in an embedded manner. The anchor rod positioning seat and the inner wall of the first guide sleeve are transversely slidably sealed. The right end of the anchor locating seat is provided with a circular groove matching the end of the anchor specimen, the axial force monitoring mechanism is installed at the left end of the anchor locating seat, and the piston rod of the first servo oil cylinder drives the anchor locating seat to move laterally through the axial force monitoring mechanism.

6. The combined stress loading anchor rapid corrosion device according to claim 5 is characterized in that: The axial force monitoring mechanism includes a first pressure sensor, a first pressure contact piece and a first linear guide assembly, wherein the first pressure sensor is fixed at the center of the left end surface of the anchor rod positioning seat, and the first pressure contact piece is located on the left side of the first pressure sensor and arranged adjacent to the stress sensing end of the first pressure sensor; The two sides of the first pressure contact sheet are movably connected to the left end of the anchor rod positioning seat through two first linear guide components symmetrically arranged about the first pressure sensor; The first linear guide assembly includes a first guide rod, a first sleeve and a first return spring. The first sleeve is arranged horizontally, and its right end is fixedly connected to the left end surface of the anchor rod positioning seat. The left end of the first guide rod is fixedly connected to the first pressure contact piece, and its right end is plugged and slidably matched with the first sleeve. The first return spring is arranged inside the first sleeve and on the right side of the first guide rod.

7. The combined stress loading anchor rapid corrosion device according to claim 1 is characterized in that: The anchor rod limiting mechanism includes a positioning disk, an arc-shaped limiting plate and a gear driving assembly. The positioning disk is a disk-shaped structure and is vertically fixed on the right side wall of the chamber where it is located. A circular cavity is opened at the center of the positioning disk, and three long slide grooves are arranged on the left side wall. The three long slide grooves are evenly distributed on the circumference of a circle with the center of the positioning disk as the center. A lead screw and a nut seat are provided on the inner side of each of the long slide grooves, the nut seat and the inner wall of the corresponding long slide groove are slidably matched along the normal direction of the positioning plate, one end of the lead screw is rotationally matched with the side wall of the long slide groove, and the other end extends to the inner side of the circular cavity, the lead screw is passed through the inner side of the nut seat and is threadedly matched with the nut seat; The left side of the positioning plate is provided with the same number of arc-shaped limit plates as the nut seats and corresponding in position to each other, the middle part of each arc-shaped limit plate is fixedly connected to the corresponding nut seat, and the electrode sheet is fixed on the outer wall of one of the arc-shaped limit plates; The gear drive assembly includes a central bevel gear and three driven bevel gears. The central bevel gear is located at the center of the circular cavity. The end of its gear shaft passes through the right side wall of the test box and is provided with an open locking block. The three driven bevel gears are respectively installed at the other ends of the three lead screws and are all meshed with the central bevel gear. The central bevel gear drives the three arc-shaped limit plates to move synchronously and in the same direction along the normal direction of the positioning plate through the lead screw.

8. The combined stress loading anchor rapid corrosion device according to claim 4 is characterized in that: The axial force loading unit comprises a force transmission rod and a radial force monitoring mechanism. The force transmission rod is arranged vertically, a cylindrical sliding seat is fixed at the lower end of the force transmission rod, and a loading end is fixedly connected at the upper end of the force transmission rod; The circumferential outer wall of the sliding seat is fixedly sleeved with a second O-ring in an embedded manner, and the sliding seat is located on the inner side of the second guide sleeve and vertically slides and seals with the inner wall of the tunnel cavity of the second guide sleeve; The radial force monitoring mechanism includes a second pressure sensor, a second pressure contact piece and a second linear guide assembly, wherein the second pressure sensor is fixed at the center of the bottom of the sliding seat, and the second pressure contact piece is located below the second pressure sensor and arranged adjacent to the stress sensing end of the second pressure sensor; There are two second linear guide assemblies and they are symmetrically arranged on both sides of the second pressure sensor. The first linear guide assembly includes a second guide rod, a second sleeve and a second return spring. The second sleeve is arranged vertically, and its upper end is fixedly connected to the bottom of the sliding seat. The second return spring is arranged inside the second sleeve. The lower end of the second guide rod is fixedly connected to the second pressure contact piece, and its upper end is passed through the second sleeve and vertically slidably matched.

9. The combined stress loading anchor rapid corrosion device according to claim 1 is characterized in that: The drip mechanism includes a drip pipe, which is horizontally arranged just above the anchor specimen in the second chamber, and has a plurality of drip nozzles at equal intervals along its length at its bottom, and a water inlet end of the drip pipe is located outside the test box and is equipped with a flow regulating valve, which is connected to a water source through a water supply pipe; A heat-sensitive probe and a humidity-sensitive probe are installed on the side wall of the upper part of each chamber, and all the heat-sensitive probes and humidity-sensitive probes are respectively connected to the temperature and humidity monitor for communication.

10. A method for rapid corrosion testing of anchor rods, characterized in that: Based on the combined stress loading anchor rapid corrosion device as described in any one of claims 1 to 9, the test method comprises the following steps: S1. Prepare three anchor rod specimens of the same specification and length, grind the two end faces of each anchor rod specimen flat, install the three anchor rod specimens into the first chamber, the second chamber and the third chamber respectively, and lay gravel and fine sand on the bottom of the third chamber; When the anchor rod specimen is installed in the corresponding chamber, the left end of the anchor rod specimen is plugged into the corresponding axial force loading unit, and the right end is fixedly connected to the side wall of the test box through the corresponding anchor rod limiting mechanism; S2, connect the left end of each anchor specimen to the positive electrode of the corresponding DC power supply through a wire, connect the negative electrode of the DC power supply to the electrode sheet at the right end of the anchor specimen through another wire, and connect a sliding rheostat and a switch in series in the circuit; S3, connecting the salt spray port on the side wall of the first chamber to the outlet pipe of the salt spray generator, and filling the salt spray generator with the configured corrosive medium salt solution; Connect the water inlet of the drip mechanism to the water supply device pipeline, and connect the water inlet and outlet of the third chamber to the external water storage tank to form a water supply circulation system. Then, fix the top cover to the top of the test box to seal the first chamber, the second chamber and the third chamber. S4, the servo hydraulic station is started, and the piston rod of each first servo oil cylinder applies an axial force to the corresponding anchor rod specimen through the axial force loading unit. When the first pressure sensor of the axial force loading unit detects that the axial force reaches the set value, the loading is stopped; The piston rod of each second servo oil cylinder applies a radial force to the middle part of the corresponding anchor rod specimen through a radial force loading unit. When the second pressure sensor of the radial force loading unit detects that the radial force reaches a set value, the loading is stopped; S5, the salt spray generator starts to work, and continuously supplies atomized corrosive medium into the first chamber through the salt spray port; The water supply device supplies water to the dripping mechanism, and the dripping mechanism continuously drips water to the surface of the anchor rod specimen in the second chamber through the dripping nozzle at the bottom thereof; The water supply circulation system injects water into the third chamber through the water inlet. After the water surface is above the anchor rod test piece in the third chamber, the drain port of the third chamber is opened to keep the water surface at a constant height. S6. The ceramic heating plates in the three chambers all start working, and the temperature and humidity monitors monitor the temperature and humidity values ​​of each chamber respectively. When the temperature of each chamber reaches the set value, the start time of the test is recorded, and the temperature of each chamber is within the set temperature range; During the test, when the first pressure sensor detects that the change in the axial force reaches 0.1% of its original set value, the first servo cylinder readjusts the axial force of the anchor specimen to its original set value; When the second pressure sensor detects that the change in the radial force reaches 0.1% of its original set value, the second servo cylinder readjusts the radial force of the anchor specimen to its original set value; Regularly drain the accumulated liquid at the bottom of the first chamber and the second chamber; S7. At the end of the test cycle, the ceramic heating plate stops working, the salt spray generator, the water supply device and the water supply circulation system are turned off, and the liquids in the three chambers are drained; The top cover of the test box was removed, and the three anchor specimens were taken out from the test box respectively, and the mechanical properties of each anchor specimen were tested.

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