Testing device for tunnel supporting system under coupling action of load and ion erosion

Abstract

The invention discloses a test device for a tunnel supporting system under the load and ion erosion coupling effect. The test device comprises a supporting platform, a liquid storage tank and a test box. According to the test device for the tunnel support system under the load and ion erosion coupling action, the solution in the test box and the solution in the liquid storage box circulates under the control of the booster pump, so that the flowing of the liquid in the test box is realized, and the flowing condition of underground water in reality is simulated; through cooperation of a plurality of valves on a test liquid supply mechanism and a test liquid backflow mechanism, the flowing form and the flowing speed of liquid are controlled, simulation of various flow velocity states of underground water is achieved, a first nut on a bolt rod compresses a loading spring between a first pressurization steel plate and a second pressurization steel plate, and the loading spring compresses the test liquid supply mechanism and the test liquid backflow mechanism. Pressure of the loading spring acts on the concrete sample through the first pressurizing steel plate and the second pressurizing steel plate, the pressed state of the concrete sample is simulated, and the device has the advantages of being simple in structure, convenient to operate, low in comprehensive manufacturing cost and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel support systems, and particularly to a test device for a tunnel support system under the coupled action of load and ion erosion. Background Art

[0002] Concrete damage is a problem that has attracted much attention in the field of civil engineering. In response to the durability damage of concrete under various environmental conditions, domestic and foreign scholars have carried out systematic research since the 1950s in aspects such as durability damage mechanisms, deterioration laws, and durability repair and improvement, and have achieved fruitful results. The salt erosion suffered by concrete structures is usually chloride or sulfate erosion. The harm of chlorides is mainly that chloride ions damage the passivation film on the surface of steel bars and accelerate the corrosion of steel bars; the deterioration effect of sulfates on concrete mainly generates expansive products through chemical reactions with concrete hydration products, causing concrete cracking, accelerating the entry of external corrosive media, moisture, gases, etc. into the interior of the concrete, resulting in the destruction of the concrete microstructure and the reduction of macroscopic properties. When a concrete structure is under load, tensile stress will be generated. When the tensile stress exceeds the tensile strength of the concrete, cracks will occur, and the occurrence of cracks will exacerbate the erosion of salts on the interior of the concrete structure; under the action of salt erosion, it will affect the durability of the concrete structure, reduce its physical and mechanical properties, and exacerbate the expansion of concrete cracks. Therefore, when a concrete structure is under the coupled action of groundwater corrosion ions and load, its deterioration mechanism is often more complex than when it is only under load or ion corrosion alone.

[0003] Most of the current indoor test studies are only limited to the coupled damage of load and ion erosion in the static water environment of the secondary lining structure of tunnels. The research objects rarely include initial supports such as anchor bolts, steel supports, and shotcrete, and it is also difficult to consider the influence of the dynamic water environment on the deterioration of the support system. Therefore, it is necessary to propose a test device for a tunnel support system under the coupled action of load and ion erosion to provide a new technical solution to solve the technical problems mentioned in the above patents. Summary of the Invention

[0004] Based on this, it is necessary to provide a test device for a tunnel support system under the coupled action of load and ion erosion in view of the above technical problems. This device can accurately simulate the coupled action of load and ion erosion on the tunnel support structure, and solves the problem that the current test devices and methods cannot comprehensively simulate the durability of the tunnel support structure under the coupled action of load and ion erosion; the solution in the test chamber and the liquid storage tank is circulated under the control of a booster pump to achieve the flow of the liquid in the test chamber and simulate the flow of groundwater in reality; through the cooperation of multiple valves on the test liquid supply mechanism and the test liquid return mechanism, the flow form and flow rate of the liquid are controlled to simulate various flow velocity states of groundwater; the first nut on the bolt rod compresses the loading spring between the first pressure plate and the second pressure plate, and the pressure of the loading spring acts on the concrete specimen through the first pressure plate and the second pressure plate to simulate the compressive state it is in; the device has many advantages such as simple structure, convenient operation, and low comprehensive cost.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A test device for a tunnel support system under the coupled action of load and ion erosion, which is applied to the test device for the durability test of the tunnel support system.

[0007] The test device for the tunnel support system under the coupled action of load and ion erosion specifically includes a support platform, a liquid storage tank, and a test chamber, and also includes a specimen loading mechanism, a test liquid return mechanism, and a test liquid supply mechanism. A liquid storage tank for storing test liquid is arranged below the support platform, a test chamber for soaking the specimen is arranged above the support platform, a specimen loading mechanism for loading the specimen is arranged in the middle of the test chamber, and a test liquid return mechanism and a test liquid supply mechanism for supplying and returning liquid to the inside of the test chamber are arranged on both sides of the test chamber;

[0008] The specimen loading mechanism includes a T-shaped footrest, a bolt rod, a loading assembly, and a fixing assembly. The top surface of the support platform is fixedly connected with a T-shaped footrest, the top surface of the T-shaped footrest is fixedly connected with the test chamber, the top surface of the T-shaped footrest is fixedly connected with a bolt rod, the top end of the bolt rod penetrates the bottom surface of the test chamber and is fixedly connected to the middle of the test chamber, and a thread groove is provided on the surface of the bolt rod.

[0009] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, the loading assembly includes a first pressure plate, a second pressure plate, a loading spring, a first nut and a docking hole. The surface of the bolt rod is slidably connected with the first pressure plate, the surface of the bolt rod is slidably connected with the second pressure plate, the surface of the bolt rod is sleeved with a loading spring, the loading spring is connected to the middle of the first pressure plate and the second pressure plate, the surface of the bolt rod is threadedly connected with the first nut, and the surface of the second pressure plate and the first pressure plate is coaxially penetrated with a docking hole.

[0010] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, the fixing assembly includes a second nut and a third nut. The surface of the bolt rod is threadedly connected with the second nut, the surface of the bolt rod is threadedly connected with the third nut, and the middle of the second nut and the third nut is connected with a second pressure plate.

[0011] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, the test liquid supply mechanism includes a booster pump, a liquid supply main pipe, a spherical filter screen and a flow splitting assembly. The top surface of the support platform is fixedly connected with a booster pump, the input end of the booster pump is fixedly provided with a liquid supply main pipe, one end of the liquid supply main pipe away from the booster pump is connected to the middle of the liquid storage tank, and one end of the liquid supply main pipe away from the booster pump is fixedly provided with a spherical filter screen.

[0012] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, the flow splitting assembly includes a liquid supply riser pipe, a liquid supply flow splitting pipe and a liquid supply control valve. The output end of the booster pump is fixedly connected with a liquid supply riser pipe, the surface of the liquid supply riser pipe is fixedly connected with a plurality of liquid supply flow splitting pipes, the middle of the liquid supply flow splitting pipe is fixedly provided with a liquid supply control valve, and the middle of the liquid supply riser pipe between two adjacent liquid supply flow splitting pipes is fixedly provided with a liquid supply control valve.

[0013] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, the test liquid return mechanism includes a liquid return flow splitting pipe, a liquid return main pipe and a liquid return control valve. The surface of the test box is fixedly provided with a plurality of liquid return flow splitting pipes, one end of the liquid return flow splitting pipe away from the test box is fixedly connected with a liquid return main pipe, one end of the liquid return main pipe away from the liquid return flow splitting pipe is connected to the middle of the liquid storage tank, and the middle of the liquid return flow splitting pipe is fixedly connected with a liquid return control valve.

[0014] As a preferred embodiment of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, a steel reinforced concrete specimen is fixedly connected to the middle of the test box by the first pressure plate, a precast concrete specimen is fixedly connected to the middle of the test box by the first pressure plate, an anchor rod concrete specimen is connected to the middle of the test box, and the anchor rod at the top of the anchor rod concrete specimen is inserted into the docking hole in the middle of the second pressure plate.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion can accurately simulate the coupled action of load and ion erosion on the tunnel support structure, and solves the problem that the current test devices and methods cannot comprehensively simulate the durability of the tunnel support structure under the coupled action of load and ion erosion; the solutions in the test box and the liquid storage tank are circulated under the control of the booster pump to realize the flow of the liquid in the test box and simulate the flow of groundwater in reality; through the cooperation of multiple valves on the test liquid supply mechanism and the test liquid return mechanism, the flow form and flow rate of the liquid are controlled to simulate various flow velocity states of groundwater; the first nut on the bolt rod compresses the loading spring between the first pressure plate and the second pressure plate, and the pressure of the loading spring acts on the concrete specimen through the first pressure plate and the second pressure plate to simulate the compressive state it is in; the device has many advantages such as simple structure, convenient operation, and low comprehensive cost.

[0017] The test device for the tunnel support system provided by the present invention can realize the recycling of the test liquid by setting a liquid storage tank, a test liquid supply mechanism and a test liquid return mechanism, and simulate the influence of groundwater on the tunnel support structure in reality; there will be a phenomenon of slag falling during the test of the test specimen in the test box, and the concrete waste residue may flow into the liquid storage tank through the liquid return shunt pipe and the liquid return main pipe. After the waste residue is precipitated by the liquid storage tank and then filtered in cooperation with the spherical filter screen arranged at the bottom of the liquid supply main pipe in the test liquid supply mechanism, a test solution without waste residue can be obtained, and then the solution is transported to the test box through the test liquid supply mechanism to realize the recycling of the solution; the spherical filter screen arranged at the bottom of the liquid supply main pipe will also reduce the damage of the booster pump caused by the influence of the waste residue, effectively improving the safety and practicability of the device, facilitating the use of the user, and being better than the traditional method.

[0018] The test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion, compared with the traditional test device that can only conduct tests on a single test specimen, the present invention can use the same test block loading mechanism to conduct tests on precast concrete specimens and steel reinforced concrete specimens, and only need to replace the test specimen; it can also make minor adjustments to the test block loading mechanism to realize the test on the bolt concrete specimen. Therefore, the device of the present invention can load the initial support system and the secondary lining of the tunnel, and has the characteristics of multi-purpose in one body and high efficiency of the system. Brief Description of the Drawings

[0019] In order to more clearly illustrate the solutions in the present invention, the following will briefly introduce the drawings required for use in the description of the embodiments. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a schematic diagram of the overall structure of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0021] Figure 2 It is a schematic diagram of the connection structure between the test block loading mechanism and the steel reinforced concrete specimen of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0022] Figure 3 It is a schematic diagram of the structure of the test block loading mechanism and the precast concrete specimen of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0023] Figure 4 It is a schematic diagram of the structure of the test block loading mechanism and the bolt concrete specimen of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0024] Figure 5 It is a schematic diagram of the structure of the test block loading mechanism of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0025] Figure 6 It is a schematic diagram of the structure of the test liquid supply mechanism of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion;

[0026] Figure 7 It is a schematic diagram of the structure of the test liquid return mechanism of the test device for the tunnel support system provided by the present invention under the coupled action of load and ion erosion.

[0027] The markings in the figures are described as follows:

[0028] 1. Support platform; 2. Liquid storage tank; 3. Test chamber; 4. Specimen loading mechanism; 5. Test liquid return mechanism; 6. Test liquid supply mechanism; 7. T-shaped footrest; 8. Bolt rod; 9. First pressure plate; 10. Second pressure plate; 11. Loading spring; 12. First nut; 13. Docking hole; 14. Second nut; 15. Third nut; 16. Booster pump; 17. Main liquid supply pipe; 18. Spherical filter screen; 19. Liquid supply riser; 20. Liquid supply shunt pipe; 21. Liquid supply control valve; 22. Liquid return shunt pipe; 23. Main liquid return pipe; 24. Liquid return control valve; 25. Steel reinforced concrete specimen; 26. Prefabricated concrete specimen; 27. Anchor bolt concrete specimen. Detailed implementation manner

[0029] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0030] As described in the background art, most of the current indoor test studies are only limited to the coupled damage of load and ion erosion in the static water environment of the secondary lining structure. The research objects rarely include initial supports such as anchor bolts, steel supports, and shotcrete, and it is also difficult to consider the influence of the dynamic water environment on the deterioration of the support system.

[0031] To solve this technical problem, the present invention provides a test device for a tunnel support system under the coupled action of load and ion erosion, which is applied to the test device for the durability test of the tunnel support system.

[0032] Specifically, please refer to Figures 1 - 7 , the test device for the tunnel support system under the coupled action of load and ion erosion specifically includes a support platform 1, a liquid storage tank 2 and a test chamber 3, and also includes a specimen loading mechanism 4, a test liquid return mechanism 5 and a test liquid supply mechanism 6. A liquid storage tank 2 for storing test liquid is arranged below the support platform 1, a test chamber 3 for soaking specimens is arranged above the support platform 1, a specimen loading mechanism 4 for loading specimens is arranged in the middle of the test chamber 3, and a test liquid return mechanism 5 and a test liquid supply mechanism 6 for returning and supplying liquid inside the test chamber 3 are arranged on both sides of the test chamber 3;

[0033] The test block loading mechanism 4 includes a T-shaped footrest 7, a bolt rod 8, a loading component, and a fixing component. The top surface of the support platform 1 is fixedly connected to the T-shaped footrest 7. The top surface of the T-shaped footrest 7 is fixedly connected to the test chamber 3. The top surface of the T-shaped footrest 7 is fixedly connected to the bolt rod 8. The top end of the bolt rod 8 penetrates the bottom surface of the test chamber 3 and is fixedly connected to the middle of the test chamber 3. Thread grooves are provided on the surface of the bolt rod 8.

[0034] The test device for the tunnel support system under the coupled action of load and ion erosion provided by the present invention can accurately simulate the coupled action of load and ion erosion on the tunnel support structure, and solves the problem that the current test devices and methods cannot comprehensively simulate the durability of the tunnel support structure under the coupled action of load and ion erosion; the solutions in the test chamber 3 and the liquid storage tank 2 are circulated under the control of the booster pump 16 to realize the flow of the liquid 3 in the test chamber, simulating the flow of groundwater in reality; through the cooperation of multiple valves on the test liquid supply mechanism 6 and the test liquid return mechanism 5, the flow form and flow rate of the liquid are controlled to simulate various flow velocity states of groundwater; the first nut 12 on the bolt rod 8 compresses the loading spring 11 between the first pressure plate 9 and the second pressure plate 10, and the pressure of the loading spring 11 acts on the concrete specimen through the first pressure plate 9 and the second pressure plate 10 to simulate the compressive state it is in; the device has many advantages such as simple structure, convenient operation, and low comprehensive cost.

[0035] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings.

[0036] Embodiment 1:

[0037] Please refer to Figures 1 - 5 , a test device for a tunnel support system under the coupled action of load and ion erosion, which includes a support platform 1, a liquid storage tank 2, and a test chamber 3, and also includes a test block loading mechanism 4, a test liquid return mechanism 5, and a test liquid supply mechanism 6. A liquid storage tank 2 for storing test liquid is provided below the support platform 1. A test chamber 3 for soaking the test block is provided above the support platform 1. A test block loading mechanism 4 for loading the test block is provided in the middle of the test chamber 3. A test liquid return mechanism 5 and a test liquid supply mechanism 6 for returning liquid and supplying liquid to the inside of the test chamber 3 are provided on both sides of the test chamber 3;

[0038] The test block loading mechanism 4 includes a T-shaped footrest 7, a bolt rod 8, a loading component, and a fixing component. The top surface of the support platform 1 is fixedly connected to the T-shaped footrest 7. The top surface of the T-shaped footrest 7 is fixedly connected to the test chamber 3. The top surface of the T-shaped footrest 7 is fixedly connected to the bolt rod 8. The top end of the bolt rod 8 penetrates through the bottom surface of the test chamber 3 and is fixedly connected to the middle of the test chamber 3. Thread grooves are provided on the surface of the bolt rod 8.

[0039] Specifically, the loading component includes a first pressure plate 9, a second pressure plate 10, a loading spring 11, a first nut 12, and a docking hole 13. The first pressure plate 9 is slidably connected to the surface of the bolt rod 8. The second pressure plate 10 is slidably connected to the surface of the bolt rod 8. A loading spring 11 is sleeved on the surface of the bolt rod 8. The loading spring 11 is connected to the middle of the first pressure plate 9 and the second pressure plate 10. The first nut 12 is threadedly connected to the surface of the bolt rod 8. Docking holes 13 are coaxially provided through the surfaces of the second pressure plate 10 and the first pressure plate 9.

[0040] Through the above structural design, when the above device is used, first place the steel reinforced concrete specimen 25 or the precast concrete specimen 26 in the middle of the four bolt rods 8 in the middle of the test chamber 3. After completion, sleeve the first pressure plate 9 on the surface of the bolt rod 8. After sleeving the first pressure plate 9, sleeve the loading springs 11 on the surface of each bolt rod 8 respectively. After sleeving the loading springs 11, sleeve the second pressure plate 10 on the surface of the bolt rod 8. After completion, install the first nut 12 on the surface of the bolt rod 8 and continuously screw the first nut 12 downward at the same time. During the process of the first nut 12 moving downward on the surface of the bolt rod 8, the second pressure plate 10 is squeezed. The second pressure plate 10 transfers the pressure it bears to the loading spring 11. The loading spring 11 transfers the pressure it bears to the first pressure plate 9. Finally, the pressure is transferred to the steel reinforced concrete specimen 25 or the precast concrete specimen 26 through the first pressure plate 9. By screwing the first nut 12 by different distances, the pressure borne by the steel reinforced concrete specimen 25 and the precast concrete specimen 26 can be increased or decreased.

[0041] Example 2:

[0042] The test device for the tunnel support system provided in Example 1 is further optimized under the coupled action of load and ion erosion. Specifically, as Figures 6 - 7 shown, the test liquid supply mechanism 6 includes a booster pump 16, a liquid supply main pipe 17, a spherical filter net 18, and a shunt component. The top surface of the support platform 1 is fixedly connected to the booster pump 16. The input end of the booster pump 16 is fixedly provided with the liquid supply main pipe 17. One end of the liquid supply main pipe 17 away from the booster pump 16 is connected to the middle of the liquid storage tank 2. A spherical filter net 18 is fixedly provided at one end of the liquid supply main pipe 17 away from the booster pump 16.

[0043] Specifically, the flow splitting component includes a liquid supply riser 19, a liquid supply flow splitting pipe 20, and a liquid supply control valve 21. The output end of the booster pump 16 is fixedly connected to the liquid supply riser 19. A plurality of liquid supply flow splitting pipes 20 are fixedly connected to the surface of the liquid supply riser 19. A liquid supply control valve 21 is fixedly arranged in the middle of the liquid supply flow splitting pipe 20. A liquid supply control valve 21 is fixedly arranged in the middle of the liquid supply riser 19 between two adjacent liquid supply flow splitting pipes 20.

[0044] Specifically, the test liquid reflux mechanism 5 includes a liquid return flow splitting pipe 22, a liquid return main pipe 23, and a liquid return control valve 24. A plurality of liquid return flow splitting pipes 22 are fixedly arranged on the surface of the test chamber 3. One end of the liquid return flow splitting pipe 22 away from the test chamber 3 is fixedly connected to the liquid return main pipe 23. One end of the liquid return main pipe 23 away from the liquid return flow splitting pipe 22 is connected to the middle of the liquid storage tank 2. A liquid return control valve 24 is fixedly connected to the middle of the liquid return flow splitting pipe 22.

[0045] Specifically, a steel reinforced concrete specimen 25 is fixedly connected between the first pressure plate 9 and the middle of the test chamber 3. A precast concrete specimen 26 is fixedly connected between the first pressure plate 9 and the middle of the test chamber 3. An anchor rod concrete specimen 27 is connected to the middle of the test chamber 3. The anchor rod at the top of the anchor rod concrete specimen 27 is inserted into the docking hole 13 in the middle of the second pressure plate 10.

[0046] Through the above structural design, after the steel reinforced concrete specimen 25 or the precast concrete specimen 26 is installed, the booster pump 16 is turned on. The booster pump 16 transports the liquid in the middle of the liquid storage tank 2 to the middle of the test chamber 3 through the liquid supply riser 19 and the liquid supply flow splitting pipe 20 via the liquid supply main pipe 17. During the transportation of the liquid, the liquid supply control valve 21 is adjusted to control the liquid scouring on different positions of the surface of the steel reinforced concrete specimen 25 or the precast concrete specimen 26. When the liquid enters the inside of the test chamber 3, it is collected to the middle of the liquid return main pipe 23 through the liquid return flow splitting pipe 22, and finally returns to the inside of the liquid storage tank 2 through the liquid return main pipe 23. When the liquid has not entered the liquid return flow splitting pipe 22, the liquid return control valve 24 can be used to control the liquid return amount of each liquid return flow splitting pipe 22.

[0047] Embodiment 3:

[0048] Further extension of the test device for the tunnel support system provided in Embodiment 1 under the coupled action of load and ion erosion. Specifically, as Figure 4 shown, the fixing component includes a second nut 14 and a third nut 15. The second nut 14 is threadedly connected to the surface of the bolt rod 8. The third nut 15 is threadedly connected to the surface of the bolt rod 8. The middle of the second nut 14 and the third nut 15 is connected to the second pressure plate 10.

[0049] Through the above structural design, when the anchor bolt concrete specimen 27 is tested, first place the anchor bolt concrete specimen 27 in the middle of the test box 3. Screw the second nuts 14 onto the surfaces of the four bolt rods 8 respectively. After completion, sleeve the second pressure plate 10 onto the surfaces of the bolt rods 8. While the second pressure plate 10 is sleeved onto the surfaces of the bolt rods 8, make the top end of the anchor bolt concrete specimen 27 pass through the docking holes 13 on the surface of the second pressure plate 10. After the second pressure plate 10 is sleeved, screw the third nut 15 onto the surface of the bolt rod 8 so that the second nut 14 and the third nut 15 cooperate to clamp the second pressure plate 10. After the second pressure plate 10 is fixed, the anchor bolt concrete specimen 27 is simultaneously fixed in the middle of the test box 3. Then, the anchor bolt concrete specimen 27 can be tested through the test liquid reflux mechanism 5 and the test liquid supply mechanism 6.

Claims

1. An experimental device for a tunnel support system under the coupled action of load and ion erosion, comprising a support platform (1), a liquid storage tank (2) and a test box (3), characterized in that, It also includes a specimen loading mechanism (4), a test liquid reflux mechanism (5) and a test liquid supply mechanism (6). A liquid storage tank (2) for storing test liquid is arranged below the support platform (1), and a test chamber (3) for soaking specimens is arranged above the support platform (1). A specimen loading mechanism (4) for loading specimens is arranged in the middle of the test chamber (3), and a test liquid reflux mechanism (5) and a test liquid supply mechanism (6) for returning and supplying liquid inside the test chamber (3) are arranged on both sides of the test chamber (3). The specimen loading mechanism (4) includes a T-shaped footrest (7), a bolt rod (8), a loading assembly and a fixing assembly. The top surface of the support platform (1) is fixedly connected with a T-shaped footrest (7), the top surface of the T-shaped footrest (7) is fixedly connected with the test chamber (3), the top surface of the T-shaped footrest (7) is fixedly connected with a bolt rod (8), the top end of the bolt rod (8) penetrates through the bottom surface of the test chamber (3) and is fixedly connected to the middle of the test chamber (3), and a thread groove is provided on the surface of the bolt rod (8).

2. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 1, characterized in that, The loading assembly includes a first pressure plate (9), a second pressure plate (10), a loading spring (11), a first nut (12) and a docking hole (13). The first pressure plate (9) is slidably connected to the surface of the bolt rod (8), the second pressure plate (10) is slidably connected to the surface of the bolt rod (8), a loading spring (11) is sleeved on the surface of the bolt rod (8), the loading spring (11) is connected to the middle of the first pressure plate (9) and the second pressure plate (10), the first nut (12) is threadedly connected to the surface of the bolt rod (8), and a docking hole (13) is coaxially penetrated through the surfaces of the second pressure plate (10) and the first pressure plate (9).

3. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 1, characterized in that, The fixing assembly includes a second nut (14) and a third nut (15). The second nut (14) is threadedly connected to the surface of the bolt rod (8), the third nut (15) is threadedly connected to the surface of the bolt rod (8), and the second pressure plate (10) is connected to the middle of the second nut (14) and the third nut (15).

4. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 1, characterized in that, The test liquid supply mechanism (6) includes a booster pump (16), a liquid supply main pipe (17), a spherical filter screen (18) and a flow splitting assembly. The top surface of the support platform (1) is fixedly connected with a booster pump (16), the input end of the booster pump (16) is fixedly provided with a liquid supply main pipe (17), one end of the liquid supply main pipe (17) away from the booster pump (16) is connected to the middle of the liquid storage tank (2), and a spherical filter screen (18) is fixedly provided at one end of the liquid supply main pipe (17) away from the booster pump (16).

5. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 4, characterized in that The shunt assembly includes a liquid supply riser (19), a liquid supply shunt pipe (20), and a liquid supply control valve (21). The output end of the booster pump (16) is fixedly connected to the liquid supply riser (19). A plurality of liquid supply shunt pipes (20) are fixedly connected to the surface of the liquid supply riser (19). A liquid supply control valve (21) is fixedly arranged in the middle of the liquid supply shunt pipe (20). A liquid supply control valve (21) is fixedly arranged in the middle of the liquid supply riser (19) between two adjacent liquid supply shunt pipes (20).

6. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 1, characterized in that, The test liquid return mechanism (5) includes a liquid return shunt pipe (22), a liquid return main pipe (23), and a liquid return control valve (24). A plurality of liquid return shunt pipes (22) are fixedly arranged on the surface of the test chamber (3). One end of the liquid return shunt pipe (22) away from the test chamber (3) is fixedly connected to the liquid return main pipe (23). One end of the liquid return main pipe (23) away from the liquid return shunt pipe (22) is connected to the middle of the liquid storage tank (2). A liquid return control valve (24) is fixedly connected to the middle of the liquid return shunt pipe (22).

7. The test device for the tunnel support system under the coupled action of load and ion erosion according to claim 2, characterized in that, A steel reinforced concrete specimen (25) is fixedly connected between the first pressure plate (9) and the middle of the test chamber (3). A precast concrete specimen (26) is fixedly connected between the first pressure plate (9) and the middle of the test chamber (3). An anchor rod concrete specimen (27) is connected to the middle of the test chamber (3). The anchor rod at the top of the anchor rod concrete specimen (27) is inserted into the docking hole (13) in the middle of the second pressure plate (10).

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