Tunnel ground stress testing device

Abstract

The utility model discloses a tunnel ground stress testing device, and belongs to the technical field of ground stress testing. Comprising a test connecting pipe and a packer rubber sleeve which is sleeved and fixed on the test connecting pipe, the packer rubber sleeve is connected with the test connecting pipe in a penetrating mode, the packer rubber sleeve is of a fusiform structure, a first packer, a second packer and a third packer are detachably installed on the test connecting pipe, and the first packer, the second packer and the third packer are connected with the test connecting pipe in a penetrating mode. The first packer is communicated with the second packer, the second packer is communicated with the third packer, the outer diameter of the first packer, the outer diameter of the second packer and the outer diameter of the third packer are sequentially increased, and the first packer is connected with the packer rubber barrel in a penetrating mode. And a plurality of test connecting pipes with different calibers do not need to be carried, so that the device is convenient to carry and use.

Description

Technical Field

[0001] The present application relates to the technical field of in-situ stress testing, and more specifically, to a tunnel in-situ stress testing device. Background Art

[0002] During the final survey stage of tunnel engineering, measuring points are generally set according to geological conditions for in-situ stress testing, aiming to understand and master the in-situ stress conditions of key sections along the line. The main purpose of in-situ stress testing in tunnels is to determine the stress distribution state of the surrounding rock after tunnel excavation, including key parameters such as the maximum horizontal principal stress, the minimum horizontal principal stress, and the vertical stress. These data are of great significance for evaluating the stability of tunnel surrounding rock and predicting the occurrence of geological disasters such as rock bursts.

[0003] Common methods for in-situ stress testing in tunnels include the hydraulic fracturing method, the stress relief method, the acoustic emission method, etc. Among them, the hydraulic fracturing method is widely used because it directly measures the principal stress value of the borehole cross-section and is simple and fast to operate.

[0004] However, during the fracturing test of the hydraulic fracturing method, pressure is applied to the two-section packer rubber cylinders through a high-pressure pump. A test section is formed between the two-section packer rubber cylinders. When injecting high-pressure water into the test section, since the rubber cylinders made of rubber material will be extruded by the high-pressure water, causing the rubber cylinders to deform, and the high-pressure water leaks from the deformed part, affecting the normal in-situ stress test. In order to reduce the extrusion of the high-pressure water on the rubber cylinders, the existing rubber packers adopt a structure design of one well with one pipe. That is to say, the rubber cylinder is sleeved on a test connection pipe adapted to the inner wall of the well, and the rubber cylinder is expanded and extruded against the well wall. The rigid part of the test connection pipe can reduce the extrusion of the high-pressure water on the rubber cylinder. Although the existing structure can solve the problem of the rubber cylinder being extruded by the high-pressure water, due to the different inner diameters of the wells in the actual use process of the one well with one pipe design, different test connection pipes and rubber cylinders are required. Therefore, connection pipes and rubber cylinders of different calibers are needed, which cannot adapt to different caliber pipe wells, and carrying a large number of test connection pipes increases the carrying burden and is not conducive to carrying and using.

[0005] In view of this, we propose a tunnel in-situ stress testing device. Utility Model Content

[0006] 1. Technical Problems to be Solved

[0007] The purpose of the present application is to provide a tunnel in-situ stress testing device, which solves the technical problems in the above background art, and realizes the technical effect of one pipe being applicable to the adjustment and use of multiple caliber pipe wells, without the need to carry multiple test connection pipes of different calibers, and is convenient for carrying and using.

[0008] 2. Technical Solutions

[0009] The technical solution of this application provides a tunnel in-situ stress testing device, which includes a test connection pipe and a packer rubber barrel sleeved and fixed on the test connection pipe. The packer rubber barrel is connected to the test connection pipe in a through manner. The packer rubber barrel is in a spindle shape. The first packer, the second packer and the third packer are detachably installed on the test connection pipe. The first packer is communicated with the second packer, and the second packer is communicated with the third packer. The outer diameters of the first packer, the second packer and the third packer increase in sequence. The first packer is connected to the packer rubber barrel in a through manner.

[0010] As an alternative solution of the technical solution of this application document, both the test connection pipe and the packer rubber barrel are provided with high-pressure gas inlet holes. A plurality of high-pressure gas outlet holes are provided on one side of the packer rubber barrel close to the first packer;

[0011] The first packer includes two first steel ring plates, a stainless steel sleeve coaxially fixed on the two first steel ring plates, and a first sealing rubber barrel sleeved on the stainless steel sleeve. The first sealing rubber barrel is placed between the two first steel ring plates. A plurality of first through holes corresponding to the high-pressure gas outlet holes are provided on the first steel ring plate. The first sealing rubber barrel is integrally formed with a first air inlet nozzle fixed in the first through hole.

[0012] As an alternative solution of the technical solution of this application document, the second packer includes two second steel ring plates, a stainless steel sleeve coaxially fixed between the two second steel ring plates, and a second sealing rubber barrel sleeved on the stainless steel sleeve. The second sealing rubber barrel is placed between the two second steel ring plates. A plurality of second through holes corresponding to the first through holes are provided on the second steel ring plate. The second sealing rubber barrel is integrally formed with a second air inlet nozzle fixed in the second through hole.

[0013] As an alternative solution of the technical solution of this application document, the third packer includes two third steel ring plates, a stainless steel sleeve coaxially fixed between the two third steel ring plates, and a third sealing rubber barrel sleeved on the stainless steel sleeve. The third sealing rubber barrel is placed between the two third steel ring plates. A plurality of third through holes corresponding to the second through holes are provided on the third steel ring plate. The third sealing rubber barrel is integrally formed with a third air inlet nozzle fixed in the third through hole. The first air inlet nozzle, the second air inlet nozzle and the third air inlet nozzle can all be threadedly connected with bolts.

[0014] As an alternative solution of the technical solution of this application document, a plurality of first positioning grooves are provided at one end of the packer rubber barrel close to the high-pressure gas outlet holes. The first steel ring plate is integrally formed with a plurality of first positioning rods adapted to and corresponding to the first positioning grooves;

[0015] The first steel ring plate is stamped with a plurality of second positioning grooves, and the second steel ring plate is integrally formed with a plurality of second positioning rods adapted to and corresponding to the second positioning grooves;

[0016] The second steel ring plate is stamped with a plurality of third positioning grooves, and the third steel ring plate is integrally formed with a plurality of third positioning rods adapted to and corresponding to the third positioning grooves;

[0017] The stainless steel sleeve is sleeved on the test connecting pipe, a nut is threadedly connected to the test connecting pipe, and a sealing ring is sleeved on the bolt.

[0018] As an alternative solution of the technical solution of the present application document, a second protective sleeve is coaxially fixed to one side of the third steel ring plate, and a first protective sleeve is coaxially fixed to one side of the second steel ring plate. The second steel ring plate and the second sealing rubber cylinder can be sleeved in the second protective sleeve, and the first steel ring plate and the first sealing rubber cylinder can be sleeved in the first protective sleeve.

[0019] 3. Beneficial effects

[0020] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0021] 1. In the present application, the outer diameters of the first packer, the second packer, and the third packer increase in sequence. Therefore, the packer can be selected according to the diameters of different wellbores. Under the combined sealing action of the packer and the packer rubber cylinder, and under the action of the packer, the pressure of the high-pressure water on the packer rubber cylinder can be reduced to improve the sealing effect of the test section of the wellbore. Different-diameter wellbores can be adjusted and used through a single test connecting pipe, which is convenient for carrying and using. Brief description of the drawings

[0022] Figure 1 Schematic structural diagram of a packer of a tunnel in-situ stress testing device disclosed in a preferred embodiment of the present application;

[0023] Figure 2 Of a tunnel in-situ stress testing device disclosed in a preferred embodiment of the present application Figure 1 Schematic sectional view;

[0024] Figure 3 Of a tunnel in-situ stress testing device disclosed in a preferred embodiment of the present application Figure 2 Enlarged structural diagram at position A;

[0025] Figure 4 Of a tunnel in-situ stress testing device disclosed in a preferred embodiment of the present application Figure 2 Enlarged structural diagram at position B;

[0026] Figure 5Schematic diagram of the packer rubber barrel structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0027] Figure 6 Schematic diagram of the first packer structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0028] Figure 7 Schematic diagram of the sectional view of the first packer of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0029] Figure 8 Schematic diagram of the second packer structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0030] Figure 9 Schematic diagram of the sectional view of the second packer of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0031] Figure 10 Schematic diagram of the third packer structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0032] Figure 11 Schematic diagram of the sectional view of the third packer of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0033] Figure 12 Of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application Figure 1 Schematic diagram of the explosion structure;

[0034] Figure 13 Schematic diagram of the first installation state structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0035] Figure 14 Schematic diagram of the second installation state structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0036] Figure 15 Schematic diagram of the third installation state structure of a tunnel ground stress testing device disclosed in a preferred embodiment of the present application;

[0037] Description of the reference numerals in the figure: 1. Test connection pipe; 11. High-pressure gas inlet hole; 12. High-pressure gas outlet hole;

[0038] 2. Packer rubber barrel; 21. First positioning groove;

[0039] 3. First packer; 31. First steel ring plate; 311. First through hole; 312. Second positioning groove; 313. First positioning rod; 32. First packer rubber cylinder; 321. First air inlet nozzle;

[0040] 4. Second packer; 41. Second steel ring plate; 411. Second through hole; 412. Third positioning groove; 413. Second positioning rod; 42. Second packer rubber cylinder; 421. Second air inlet nozzle; 43. First protective sleeve;

[0041] 5. Third packer; 51. Third steel ring plate; 511. Third through hole; 512. Third positioning rod; 52. Third packer rubber cylinder; 521. Third air inlet nozzle; 53. Second protective sleeve;

[0042] 6. Nut; 7. Sealing washer; 8. Stainless steel casing; 9. Bolt; 91. Sealing ring. Detailed implementation mode

[0043] The present application will be further described in detail below with reference to the accompanying drawings of the specification.

[0044] A tunnel in-situ stress testing device includes a test connection pipe 1 and a packer rubber cylinder 2 sleeved and fixed on the test connection pipe 1. The packer rubber cylinder 2 is connected to the test connection pipe 1 in a through manner. The packer rubber cylinder 2 has a spindle-shaped structure. A first packer 3, a second packer 4, and a third packer 5 are detachably installed on the test connection pipe 1. The first packer 3 is connected to the second packer 4, and the second packer 4 is connected to the third packer 5. The outer diameters of the first packer 3, the second packer 4, and the third packer 5 increase in sequence. The first packer 3 is connected to the packer rubber cylinder 2 in a through manner.

[0045] Refer to Figures 1 - 5 , a test section is formed between the packer rubber cylinders 2 of two adjacent test connection pipes 1. And an external threaded pipe is coaxially fixed at the end of the test connection pipe 1 to facilitate threaded connection with a plug to block the opening of the lower test connection pipe 1. With the spindle-shaped structure design of the packer rubber cylinder 2, the expansion outer diameter of the packer rubber cylinder 2 can be increased. Since the outer diameters of the first packer 3, the second packer 4, and the third packer 5 increase in sequence, packers can be selected according to the calibers of different pipe wells. Under the combined sealing action of the packers and the packer rubber cylinder 2, the pressure of high-pressure water on the packer rubber cylinder 2 can be reduced under the action of the packers, so as to improve the sealing effect of the test section of the pipe well. Different-caliber pipe wells can be adjusted and used through one test connection pipe 1.

[0046] Both the test connection pipe 1 and the packer rubber cylinder 2 are provided with high-pressure gas inlet holes 11, and a plurality of high-pressure gas outlet holes 12 are provided on one side of the packer rubber cylinder 2 close to the first packer 3;

[0047] The first packer 3 includes two first steel ring plates 31, a stainless steel sleeve 8 coaxially fixed to the two first steel ring plates 31, and a first packer rubber cylinder 32 sleeved on the stainless steel sleeve 8. The first packer rubber cylinder 32 is placed between the two first steel ring plates 31. A plurality of first through holes 311 corresponding to the high-pressure gas outlet holes 12 are formed in the first steel ring plates 31. The first packer rubber cylinder 32 is integrally formed with a first air inlet nozzle 321 fixed in the first through holes 311.

[0048] Refer to Figure 3 and Figures 5 - 7 , the packer rubber cylinder 2 is sleeved and fixed on the test connection pipe 1, and the test connection pipe 1 is connected to the air outlet of the high-pressure air pump through a high-pressure air pipe. High-pressure gas enters the packer rubber cylinder 2 through the high-pressure gas inlet hole 11, causing the packer rubber cylinder 2 to expand and squeeze against the inner wall of the wellbore. The outer diameter of the first steel ring plate 31 is larger than the outer diameter of the test connection pipe 1. The stainless steel sleeve 8 of the first steel ring plate 31 is sleeved and fixed on the test connection pipe 1, and the high-pressure gas outlet hole 12 is made to correspond to the first through holes 311. High-pressure gas enters the first packer rubber cylinder 32 through the first air inlet nozzle 321. The remaining first through holes 311 are blocked by bolts 9. At this time, the high-pressure gas can inflate the packer rubber cylinder 2 and the first packer rubber cylinder 32 and then expand and squeeze against the inner wall of the pipe well, and reduce the extrusion of the high-pressure water in the test section on the packer rubber cylinder 2 and the first packer rubber cylinder 32 through the first steel ring plate 31.

[0049] The second packer 4 includes two second steel ring plates 41, a stainless steel sleeve 8 coaxially fixed between the two second steel ring plates 41, and a second packer rubber cylinder 42 sleeved on the stainless steel sleeve 8. The second packer rubber cylinder 42 is placed between the two second steel ring plates 41. A plurality of second through holes 411 corresponding to the first through holes 311 are formed in the second steel ring plates 41. The second packer rubber cylinder 42 is integrally formed with a second air inlet nozzle 421 fixed in the second through holes 411.

[0050] Refer to Figure 3 and Figure 8 and Figure 9, both the second steel ring plate 41 and the second sealing rubber cylinder 42 are larger than the outer diameter of the first steel ring plate 31. When the diameter of the pipe well is larger than the first steel ring plate 31 and smaller than the third steel ring plate 51, the stainless steel casing 8 is sleeved on the test connection pipe 1, and the second steel ring plate 41 can directly abut against the first steel ring plate 31 without removing the first steel ring plate 31. Then, the second through hole 411 is aligned with the first through hole 311 to connect the first air inlet nozzle 321 and the second air inlet nozzle 421. The second packer 4 is fixed on the test connection pipe 1, and the remaining second through holes 411 are blocked by threaded connection with bolts 9. At this time, when the high-pressure air pump inflates the test connection pipe 1, the packer rubber cylinder 2, the second sealing rubber cylinder 42, and the first sealing rubber cylinder 32 are inflated and abut against the inner wall of the pipe well, thereby improving the sealing effect of the test section, and reducing the extrusion of the high-pressure water on the sealing rubber cylinder through the second steel ring plate 41.

[0051] The third packer 5 includes two third steel ring plates 51, a stainless steel casing 8 coaxially fixed between the two third steel ring plates 51, and a third sealing rubber cylinder 52 sleeved on the stainless steel casing 8. The third sealing rubber cylinder 52 is placed between the two third steel ring plates 51. A plurality of third through holes 511 corresponding to the second through holes 411 are formed in the third steel ring plate 51. The third sealing rubber cylinder 52 is integrally formed with a third air inlet nozzle 521 fixed in the third through hole 511. The first air inlet nozzle 321, the second air inlet nozzle 421, and the third air inlet nozzle 521 can all be threadedly connected with bolts 9.

[0052] Refer to Figure 4 and Figure 10 and Figure 11 , when the diameter of the pipe well is adapted to the third steel ring plate 51, or the diameter of the pipe well is smaller than the maximum expansion outer diameter of the third sealing rubber cylinder 52, the stainless steel casing 8 of the third steel ring plate 51 is directly sleeved on the test connection pipe 1, and the third through hole 511 is aligned with the second through hole 411. At this time, the third air inlet nozzle 521 is connected to the second air inlet nozzle 421, and the remaining third through holes 511 are blocked by threaded connection with bolts 9. After the high-pressure gas enters, the packer rubber cylinder 2, the first sealing rubber cylinder 32, the second sealing rubber cylinder 42, and the third sealing rubber cylinder 52 can be inflated and abut against the inner wall of the pipe well, and the extrusion force of the water pressure on the rubber cylinder is reduced through the third steel ring plate 51.

[0053] A plurality of first positioning grooves 21 are formed at one end of the packer rubber cylinder 2 close to the high-pressure gas outlet hole 12. The first steel ring plate 31 is integrally formed with a plurality of first positioning rods 313 adapted to and corresponding to the first positioning grooves 21;

[0054] The first steel ring plate 31 is stamped with a plurality of second positioning grooves 312. The second steel ring plate 41 is integrally formed with a plurality of second positioning rods 413 adapted to and corresponding to the second positioning grooves 312;

[0055] The second steel ring plate 41 is stamping formed with a plurality of third positioning grooves 412, and the third steel ring plate 51 is integrally formed with a plurality of third positioning rods 512 adapted to and corresponding to the third positioning grooves 412;

[0056] The stainless steel sleeve 8 is sleeved on the test connecting pipe 1. A nut 6 is threadedly connected to the test connecting pipe 1, and a sealing ring 91 is sleeved on the bolt 9.

[0057] Refer to Figures 6 - 11 and insert the first positioning rod 313 into the first positioning groove 21 to align the first through hole 311 of the first steel ring plate 31 with the high-pressure gas outlet hole 12. Insert the second positioning rod 413 into the second positioning groove 312, which can align the first through hole 311 and the second through hole 411. Insert the third positioning rod 512 into the third positioning groove 412, which can align the second through hole 411 and the third through hole 511, and can prevent misalignment between the through holes, ultimately ensuring the gas connection between the air inlets. At the same time, a sealing ring 91 is sleeved on the bolt 9 to improve the sealing performance between the bolt 9 and the through hole. It should be noted that a sealing washer 7 can be placed between the first steel ring plate 31 and the packer rubber barrel 2, between the first steel ring plate 31 and the second steel ring plate 41, and between the second steel ring plate 41 and the third steel ring plate 51, thereby improving the sealing performance between the steel ring plates. Through the threaded connection between the nut 6 and the test connecting pipe 1, under the extrusion of the nut 6, the first packer 3, the second packer 4, and the third packer 5 are fixed and mutually extruded on the test connecting pipe 1.

[0058] A second protective sleeve 53 is coaxially fixed to one side of the third steel ring plate 51, and a first protective sleeve 43 is coaxially fixed to one side of the second steel ring plate 41. The second steel ring plate 41 and the second packer rubber barrel 42 can be sleeved in the second protective sleeve 53, and the first steel ring plate 31 and the first packer rubber barrel 32 can be sleeved in the first protective sleeve 43.

[0059] Refer to Figure 3 、 Figure 9 、 Figure 11 、 Figure 13 、 Figure 14 and Figure 15 When using the second packer 4 and the third packer 5, the first protective sleeve 43 can be sleeved on the first packer rubber barrel 32. During inflation, under the limitation of the first protective sleeve 43, the first packer rubber barrel 32 can avoid the problem of bursting due to excessive expansion when used in a large-diameter pipe well, thereby increasing the service life of the first packer rubber barrel 32. Sleeve the second protective sleeve 53 on the second packer rubber barrel 42, which can avoid the problem of bursting due to excessive expansion when the second packer rubber barrel 42 is used in a large-diameter pipe well, thereby increasing the service life of the second packer rubber barrel 42.

[0060] Working principle: Take Figure 13For example, the stainless steel sleeve 8 of the first steel ring plate 31 is sleeved on the test connection pipe 1, and the first positioning rod 313 is inserted into the first positioning groove 21. The stainless steel sleeve 8 of the second steel ring plate 41 is sleeved on the test connection pipe 1, and the second positioning rod 413 is inserted into the second positioning groove 312. The stainless steel sleeve 8 of the third steel ring plate 51 is sleeved on the test connection pipe 1, and the third positioning rod 512 is inserted into the third positioning groove 412. At the same time, the first sealing rubber cylinder 32 is sleeved in the first protective sleeve 43, and the second sealing rubber cylinder 42 is sleeved in the second protective sleeve 53. The high-pressure gas outlet hole 12 is communicated with the first through hole 311, the second through hole 411 and the third through hole 511, and is threadedly connected to the third through hole 511 at the lower end through the bolt 9, so that the first sealing rubber cylinder 32, the second sealing rubber cylinder 42, the third sealing rubber cylinder 52 and the packer rubber cylinder 2 form a sealing structure. The two sections of the test connection pipe 1 are threadedly connected, and the lower test connection pipe 1 is sealed by a threaded connection plug. A closed test section is formed between the two groups of third packers 5. High-pressure gas is added into the upper test connection pipe 1 through a high-pressure air pump, so that the packer rubber cylinder 2 and the third sealing rubber cylinder 52 expand and squeeze against the well wall to complete the sealing. It should be noted that the high-pressure water pipe penetrates and is fixed on the test connection pipe 1, and the water outlet end is placed between the test sections (this is a conventional means in the technical field, so it is not shown in the figure), and then the test section can be filled with water and pressurized.

Claims

1. A tunnel geostress testing device, comprising a test connecting pipe (1) and a packer rubber cylinder (2) sleeved and fixed on the test connecting pipe (1), characterized in that: The packer rubber cylinder (2) is connected to the test connection pipe (1) in a through-connection manner. The packer rubber cylinder (2) is a shuttle-shaped structure. The test connection pipe (1) is detachably mounted with a first packer (3), a second packer (4) and a third packer (5). The first packer (3) is connected to the second packer (4), and the second packer (4) is connected to the third packer (5). The outer diameters of the first packer (3), the second packer (4) and the third packer (5) increase in sequence. The first packer (3) is connected to the packer rubber cylinder (2).

2. A tunnel ground stress testing device according to claim 1, characterized in that: The test connection pipe (1) and the packer rubber cylinder (2) are both provided with a high-pressure gas inlet hole (11), and a side of the packer rubber cylinder (2) close to the first packer (3) is provided with a plurality of high-pressure gas outlet holes (12); The first seal (3) comprises two first steel ring plates (31), a stainless steel sleeve (8) coaxially fixed on the two first steel ring plates (31), and a first seal rubber tube (32) sleeved on the stainless steel sleeve (8); the first seal rubber tube (32) is placed between the two first steel ring plates (31); the first steel ring plates (31) are provided with a plurality of first through holes (311) corresponding to the high-pressure gas outlet holes (12); the first seal rubber tube (32) is integrally formed with a first air inlet nozzle (321) fixed in the first through hole (311).

3. A tunnel geostress testing device according to claim 2, characterized in that: The second seal (4) comprises two second steel ring plates (41), a stainless steel sleeve (8) coaxially fixed between the two second steel ring plates (41), and a second seal rubber tube (42) sleeved on the stainless steel sleeve (8); the second seal rubber tube (42) is placed between the two second steel ring plates (41); the second steel ring plates (41) are provided with a plurality of second through holes (411) corresponding to the first through holes (311); the second seal rubber tube (42) is integrally formed with a second air inlet nozzle (421) fixed in the second through hole (411).

4. A tunnel geostress testing device according to claim 3, characterized in that: The third seal (5) comprises two third steel ring plates (51), a stainless steel sleeve (8) coaxially fixed between the two third steel ring plates (51), and a third seal rubber tube (52) sleeved on the stainless steel sleeve (8); the third seal rubber tube (52) is placed between the two third steel ring plates (51); the third steel ring plates (51) are provided with a plurality of third through holes (511) corresponding to the second through holes (411); the third seal rubber tube (52) is integrally formed with a third air inlet nozzle (521) fixed in the third through hole (511); the first air inlet nozzle (321), the second air inlet nozzle (421) and the third air inlet nozzle (521) can all be threadedly connected with bolts (9).

5. A tunnel ground stress testing device according to claim 4, characterized in that: A plurality of first positioning grooves (21) are formed at one end of the packer rubber cylinder (2) close to the high-pressure gas outlet hole (12), and a plurality of first positioning rods (313) adapted to and corresponding to the first positioning grooves (21) are integrally formed on the first steel ring plate (31); The first steel ring plate (31) is stamped with a plurality of second positioning grooves (312), and the second steel ring plate (41) is integrally formed with a plurality of second positioning rods (413) adapted to and corresponding to the second positioning grooves (312); The second steel ring plate (41) is stamped with a plurality of third positioning grooves (412), and the third steel ring plate (51) is integrally formed with a plurality of third positioning rods (512) adapted to and corresponding to the third positioning grooves (412); The stainless steel sleeve (8) is sleeved on the test connection pipe (1), a nut (6) is threadedly connected to the test connection pipe (1), and a sealing ring (91) is sleeved on the bolt (9).

6. A tunnel geostress testing device according to claim 5, characterized in that: The third steel ring plate (51) is coaxially fixed with a second protective sleeve (53) on one side, and the second steel ring plate (41) is coaxially fixed with a first protective sleeve (43) on one side. The second steel ring plate (41) and the second sealing rubber tube (42) can be sleeved in the second protective sleeve (53), and the first steel ring plate (31) and the first sealing rubber tube (32) can be sleeved in the first protective sleeve (43).

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