Test device and test method for load-bearing performance of protection system

Abstract

The present invention discloses a device and a method for testing the bearing performance of a protection system. The device comprises: an impact-resistant test bench, an upper surrounding rock interface system, a lower surrounding rock interface system and an anchor net support system. The impact-resistant test bench comprises: two impact-resistant side walls, a plurality of carbon dioxide fracturing tubes and a plurality of partition plates. The plurality of partition plates are arranged between the upper surrounding rock interface system and the lower surrounding rock interface system to separate a plurality of independent rock burst simulation test spaces. The space between the upper surrounding rock interface system and the lower surrounding rock interface system is used for pouring concrete to simulate the restoration of a tunnel structure. The anchor net support system is arranged on the inner wall of the simulated restoration tunnel structure. The present invention realizes accurate simulation of rock bursts at different positions by controlling the carbon dioxide to pass into the carbon dioxide fracturing tubes in different chambers, and detects the bearing performance of the protection system at different rock burst positions. The controllability is not only stronger, but also no harmful gas is generated, and the safety is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel dynamic disaster prevention and control, and in particular to a protection system bearing performance test device and a test method. Background Art

[0002] Faced with the increasingly severe disaster prevention and control situation and the increasingly stringent requirements for engineering disaster prevention and mitigation, it is urgent to implement scientific and effective rockburst disaster prevention and control countermeasures to ensure the safety of engineering construction. Based on this, based on the new concept of "plastic replacing steel" rockburst protection, a new energy-absorbing and buffering flexible net has been developed. This rockburst protection system is constructed with the flexible net as the core, supplemented by existing anchor rods and shotcrete as components. However, after tunnel blasting, stress release occurs. After the concentrated stress release is completed, the timing and space of the rockburst are uncertain, making it difficult to verify the reliability of the protection system through field tests. In addition, there are currently few test devices in laboratories that can reproduce the ejection phenomenon of tunnel blast blocks. Therefore, a test device that can reproduce the dynamic disaster of tunnel rockburst is needed to verify the protective performance differences of various new rockburst protection systems.

[0003] Current laboratory approaches to simulating tunnel rockbursts using test equipment have drawbacks. Small-scale model tests often employ a combination of static and dynamic loading to simulate tunnel rockbursts. Initial static stresses dominate the rock failure process, while dynamic stresses trigger surrounding rock failure. Small-scale model tests can reveal rockburst mechanisms and catastrophic evolution, but due to the limited specimen size, protection systems cannot be scaled down to such a small size, making analysis of the impact resistance of different protection systems relatively difficult. While large-scale model tests can simulate rockbursts to test the impact resistance of different protection systems, they typically simulate rockbursts by applying high in-situ stresses and disturbance stresses using a hydraulic servo system. However, due to the nonlinearity, time-varying nature, uncertainty in internal parameters, and the complexity of external disturbances, hydraulic servo systems struggle to fully simulate the complex interactions of multidimensional stresses. This makes it difficult to precisely control the rockburst location and, even more challenging, to test the load-bearing performance of protection systems at different rockburst locations. Summary of the Invention

[0004] The purpose of the present invention is to provide a protection system bearing performance test device and test method, which can realize accurate simulation of rock bursts at different positions and detect the bearing performance of the protection system under controllable conditions.

[0005] The technical solution of the present invention is:

[0006] A protective system bearing performance test device is used to monitor the bearing performance of the protective system under the impact load of rock burst blocks, comprising: an impact test bench, the impact test bench comprising: two impact-resistant side walls, which are arc-shaped structures, and a plurality of fracturing tube installation holes are provided along the arc direction of the impact-resistant side walls; a plurality of carbon dioxide fracturing tubes are correspondingly inserted into the plurality of fracturing tube installation holes; the carbon dioxide fracturing tubes utilize the physical expansion characteristics generated during the phase change of carbon dioxide to directly act on the impact energy in the surrounding medium, and the surrounding medium is ruptured by the impact of carbon dioxide, and high-pressure gas can invade the cracks, causing them to continue to expand; a plurality of partition plates are arranged between the upper interface system of the surrounding rock and the lower interface system of the surrounding rock, and are used to separate a plurality of independent rock burst simulation test spaces to prevent mutual influence between the multiple spaces during the rock burst simulation; the plurality of partition plates are respectively: a vault partition plate and an arch spandrel partition plate. The upper interface system of the surrounding rock is arranged between the two impact-resistant side walls and is located near the outer arc position of the two impact-resistant side walls. The upper interface system of the surrounding rock includes multiple external movable plates, all of which are arc-shaped plates, and the multiple external movable plates are spliced ​​into an arch bridge structure, and the curvature of the arch bridge structure is consistent with the curvature of the impact-resistant side wall. Concrete grouting holes are opened on the external movable plate at the top position; the lower interface system of the surrounding rock includes multiple inner movable plates. The lower interface system of the surrounding rock is consistent with the structure of the upper interface system of the surrounding rock and is arranged between the two impact-resistant side walls and is located near the inner arc position of the two impact-resistant side walls. The space between the upper interface system of the surrounding rock and the lower interface system of the surrounding rock is used for pouring concrete to simulate the restoration of the tunnel structure; the anchor net support system is arranged on the inner wall of the simulated restoration tunnel structure.

[0007] Furthermore, it also includes: a seismic base, on which the impact test bench is arranged; an impact-resistant support member, one end of which is connected to the seismic base and the other end is connected to the impact-resistant side wall, for improving the impact resistance of the impact test bench.

[0008] Furthermore, it also includes a surrounding rock cleaning system, which includes: a slag transport track, which is arranged on the surface of the seismic base and is located below the surrounding rock lower interface system; a slag transport vehicle, which is arranged on the slag transport track and moves along the slag transport track, and the slag transport vehicle and the slag transport track are used to realize the function of quickly collecting and cleaning the surrounding rock material after the test.

[0009] Furthermore, a shock-absorbing and energy-absorbing layer is provided on the inner side of each outer movable plate of the surrounding rock upper interface system, and the shock-absorbing and energy-absorbing layer is filled with sand to improve the ability to absorb blasting vibration energy.

[0010] Furthermore, after tunnel blasting, concrete is sprayed onto the surrounding rock to form a primary shotcrete layer. The anchor-net support system includes a flexible net, which is supported on the inner wall of the tunnel structure and closely adheres to the inner wall of the primary shotcrete layer; and multiple anchor rods, constructed in a square or plum blossom pattern and inserted into the inner wall of the tunnel structure. Anchor rod gaskets are used to secure the flexible net. When impacted, the impact force is transmitted from the flexible net to the anchor rods, providing a protective shield.

[0011] Furthermore, a method for testing the load-bearing performance of a protective system is provided, using the above-mentioned testing device to conduct a test, comprising the following steps:

[0012] Preparation stage: Install the test device, first install the seismic base to the predetermined position, arrange the slag transport track in the middle of the seismic base, fix the impact-resistant side wall, the outer movable plate at the bottom and the inner movable plate at the bottom with bolts, fill the internal space surrounded by the two impact-resistant side walls, the outer movable plate at the bottom and the inner movable plate at the bottom with concrete, and after the initial setting is completed, continue to install the outer movable plate at the shoulder, the inner movable plate at the shoulder and a partition plate on the movable plate at the bottom, and fill the concrete again. After the initial setting, install the outer movable plate at the top, the outer movable plate at the top, the inner movable plate at the top and a partition plate on the corresponding shoulder movable plate, and continue to carry out the final concrete pouring work through the concrete grouting holes. During the concrete pouring process of each part, the carbon dioxide fracturing tube is pre-buried in the impact test bench through the fracturing tube installation hole. After the concrete pouring work is completed, it is cured to achieve the target strength.

[0013] After the concrete has solidified, all the inner movable plates of the surrounding rock interface system will be dismantled to restore the real single-face tunnel state.

[0014] Vault test phase: Drill holes in the simulated tunnel inner wall, install the anchor net support system, anchor rods and flexible nets, install impact-resistant supports, connect the carbon dioxide fracturing tubes in series at the vault position, control the internal carbon dioxide filling volume to simulate rockbursts of different energy levels, and activate the carbon dioxide fracturing tubes through the detonator to release energy to destroy the concrete body and form explosive blocks to impact the anchor net support system to test the impact resistance of the anchor net support system.

[0015] Spandrel and side wall test phase: During the crown test, the concrete at the spandrel and side wall positions will not be affected due to the presence of the crown partition plate. When the test continues, the carbon dioxide fracturing tubes at the spandrel position are connected in series. After detonation, the bearing capacity of the anchor net support system at the spandrel position is tested. Then, the rockburst simulation test at the side wall position is repeated to complete the rockburst simulation at all positions in the tunnel.

[0016] Furthermore, after completing the rock burst simulation of the arch crown and the arch shoulder, the slag truck needs to be moved to the bottom of the impact test bench through the slag track, and the remaining concrete needs to be cleaned into the slag truck and transported to the waste storage area for unified placement before conducting subsequent rock burst tests.

[0017] After the test is completed, there is no need to dismantle the outer movable panels of the vault, the outer movable panels of the spandrel and the outer movable panels of the side wall. It is only necessary to reinstall the inner movable panels of the vault, the inner movable panels of the spandrel and the inner movable panels of the side wall and pour concrete to carry out the next blasting simulation test.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention simulates rockbursts by using carbon dioxide fracturing tubes to create explosive blocks at the free surface formed by the interface system between the impact test bench and the surrounding rock. Liquid CO2 phase change fracturing technology is used to conduct rock blasting tests. The blasting system excites CO2 from liquid to gaseous phase through high heat, and utilizes the high-pressure shock wave generated by the instantaneous expansion of the gas to achieve the effect of projecting rock blocks. The impact test bench and the surrounding rock interface system uses partitions to divide the monolithic arched concrete into separate chambers for the vault, spandrel, and sidewalls. By controlling the flow of carbon dioxide into the carbon dioxide fracturing tubes in different chambers, the location of the rockburst is controlled, achieving precise simulation of rockbursts at different locations and testing the load-bearing performance of the protection system at different rockburst locations. By controlling the amount of carbon dioxide used, simulation of different rockburst levels can be achieved, resulting in greater controllability, no harmful gas generation, and increased safety.

[0020] The present invention uses a carbon dioxide fracturing tube to reproduce the rock burst phenomenon without constructing a ground stress field, which greatly saves equipment manufacturing cost and difficulty.

[0021] The present invention can further test the bearing capacity of components of the anchor net support system without the need for scaled design, and the test results are more reliable.

[0022] The present invention reduces the impact of blasting energy on position device components such as side and top surfaces other than the bottom surface through the shock-absorbing and energy-absorbing layer provided on the inner side of each outer movable plate of the surrounding rock upper interface system and the impact-resistant support parts between the seismic base and the impact-resistant test bench, so as to better concentrate the energy on the single air-facing surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a three-dimensional diagram of the external schematic diagram of the overall structure of the present invention.

[0024] Figure 2 It is a front view of the overall structural diagram of the present invention.

[0025] Figure 3 for Figure 2Schematic diagram of the front cross-section structure.

[0026] Figure 4 It is a three-dimensional diagram of the internal schematic diagram of the overall structure of the present invention.

[0027] Figure 5 Schematic diagram of the positional relationship between the anchor net support system of the present invention and the restored tunnel inner wall.

[0028] Figure 6 Schematic diagram of the anchor net support system structure.

[0029] Among them, 1. Impact test bench, 11. Impact-resistant side wall, 12. Fracturing pipe installation hole, 13. Vault partition plate, 14. Spandrel partition plate, 15. Carbon dioxide fracturing pipe, 2. Surrounding rock upper interface system, 21. Concrete grouting hole, 22. Vault outer movable plate, 23. Spandrel outer movable plate, 24. Side wall outer movable plate, 25. Shock-absorbing energy-absorbing layer, 3. Surrounding rock lower interface system, 31. Vault inner movable plate, 32. Spandrel inner movable plate, 33. Side wall inner movable plate, 4. Impact-resistant support, 5. Surrounding rock cleaning system, 51. Slag truck, 52. Slag track, 6. Seismic base, 7. Anchor net support system, 71. Anchor rod, 72. Flexible net. DETAILED DESCRIPTION

[0030] The following combination Figures 1 to 6 , a detailed description of the specific embodiments of the present invention is provided. In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limiting the present invention.

[0031] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features; and in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0032] Example

[0033] like Figure 1 As shown, a protection system bearing performance test device is used to monitor the bearing performance of the protection system under the impact load of rock burst blocks, including: an impact test bench 1, a surrounding rock upper interface system 2, a surrounding rock lower interface system 3 and an anchor net support system 7, as shown in FIG. Figure 3 and Figure 4 As shown, the impact test bench 1 includes: two impact-resistant side walls 11, multiple carbon dioxide fracturing tubes 15 and multiple partitions. The two impact-resistant side walls 11 are arc-shaped structures, and multiple fracturing tube installation holes 12 are opened along the arc direction of the impact-resistant side walls 11; multiple carbon dioxide fracturing tubes 15 are correspondingly inserted into the multiple fracturing tube installation holes 12; the carbon dioxide fracturing tubes 15 use the physical expansion characteristics generated during the phase change of carbon dioxide to directly act on the surrounding medium with the impact energy. The surrounding medium is ruptured by the impact of carbon dioxide, and high-pressure gas can invade the cracks, causing them to continue to expand. In this embodiment, carbon dioxide gas can be converted into liquid under a certain high pressure. The liquid carbon dioxide is compressed into a cylindrical container by a high-pressure pump. The cylindrical container, such as a blasting tube, is loaded with a safety film, a rupture disc, a heat conductive rod and a sealing ring. The alloy cap is tightened to complete the preparations before blasting. The blasting tube, the initiator and the power cord are brought to the blasting site, the blasting tube is inserted into the drilled hole and fixed, and the initiator power supply is connected. When microcurrent passes through the high thermal conductivity rod, high temperature is generated to break through the safety membrane, instantly gasifying the liquid carbon dioxide, which expands rapidly to produce a high-pressure shock wave, causing the pressure relief valve to open automatically. The liquid carbon dioxide absorbs heat and expands rapidly to produce high pressure, causing the rock mass to crack. The multiple partitions are: a dome partition 13 and a spandrel partition 14. The multiple partitions are arranged between the upper interface system 2 of the surrounding rock and the lower interface system 3 of the surrounding rock, and are used to separate multiple independent rock burst simulation test spaces to prevent the multiple spaces from affecting each other during the rock burst simulation. The upper interface system 2 of the surrounding rock is arranged between the two impact-resistant side walls 11, and is located near the outer arc position of the two impact-resistant side walls 11. The upper interface system 2 of the surrounding rock includes multiple external movable plates, all of which are arc-shaped plates, namely the dome external movable plate 22, the spandrel external movable plate 23 and the side wall external movable plate 24. The multiple external movable plates are spliced ​​to form an arch bridge structure, and the arch bridge structure is formed. The curvature of the bridge structure is consistent with that of the impact-resistant side wall 11, and a concrete grouting hole 21 is opened on the outer movable plate at the top position; the surrounding rock lower interface system 3 includes multiple inner movable plates, which are: the arch inner movable plate 31, the arch shoulder inner movable plate 32 and the side wall inner movable plate 33. The surrounding rock lower interface system 3 has the same structure as the surrounding rock upper interface system 2 and is arranged between the two impact-resistant side walls 11, located near the inner arc position of the two impact-resistant side walls 11. The space between the surrounding rock upper interface system 2 and the surrounding rock lower interface system 3 is used for pouring concrete to simulate the restoration of the tunnel structure; the anchor net support system 7 is arranged on the inner wall of the simulated restoration tunnel structure.

[0034] In some embodiments, as Figure 1 and Figure 2As shown, the shock test bench 1 also includes a shock-resistant base 6 and an impact-resistant support member 4. The shock test bench 1 is set on the shock-resistant base 6. One end of the impact-resistant support member 4 is connected to the shock-resistant base 6, and the other end is connected to the impact-resistant side wall 11, which is used to improve the impact resistance of the shock test bench 1.

[0035] like Figure 1 and Figure 4 As shown, it also includes a surrounding rock cleaning system 5, which includes: a slag transport track 52 and a slag transport vehicle 51. The slag transport track 52 is set on the surface of the seismic base 6 and is located below the surrounding rock lower interface system 3; the slag transport vehicle 51 is set on the slag transport track 52 and moves along the slag transport track 52. The slag transport vehicle 51 and the slag transport track 52 realize the function of quickly collecting and cleaning the surrounding rock materials after the test.

[0036] A shock-absorbing and energy-absorbing layer 25 is provided on the inner side of each outer movable plate of the surrounding rock upper interface system 2. The shock-absorbing and energy-absorbing layer 25 is filled with sand to improve the ability to absorb blasting vibration energy.

[0037] After tunnel blasting, concrete will be sprayed on the surrounding rock to form the initial sprayed concrete layer, such as Figure 5 and Figure 6 As shown, the anchor-net support system 7 comprises a flexible net 72 and multiple anchor rods 71. The flexible net 72 supports the inner wall of the tunnel structure. The multiple anchor rods 71 ​​are arranged in a square or plum blossom pattern and inserted into the inner wall of the tunnel structure. Anchor rod gaskets are used to secure the flexible net 72. When impacted, the impact force is transferred from the flexible net 72 to the anchor rods 71, providing protection.

[0038] A method for testing the load-bearing performance of a protective system, using the above-mentioned testing device to conduct a test, comprises the following steps:

[0039] Preparation stage: Install the test device, first install the seismic base 6 to the predetermined position, arrange the slag transport track 52 in the middle of the seismic base 6, fix the impact-resistant side wall 11, the side wall outer movable plate 24 and the side wall inner movable plate 33 by bolts, fill the internal space with concrete, and after the initial setting is completed, continue to install the arch spandrel outer movable plate 23, the arch spandrel inner movable plate 32 and the arch spandrel partition plate 14 on the bottom movable plate, and fill the concrete again. After the initial setting, install the arch crown outer movable plate 22, the arch crown inner movable plate 31 and the arch crown partition plate 13 on the corresponding shoulder movable plate, and continue to carry out the final concrete pouring work through the concrete grouting hole 21. During the concrete pouring process of each part, the carbon dioxide fracturing tube 15 is pre-buried in the impact test bench 1 through the fracturing tube installation hole 12. After the concrete pouring work is completed, it is cured to reach the target strength.

[0040] After the concrete solidifies, all the inner movable plates of the surrounding rock lower interface system 3 are dismantled to restore the real tunnel single-face state.

[0041] Arch test phase: Drill holes at the simulated tunnel inner wall position, install the anchor rods 71 ​​and flexible nets 72 of the anchor net support system 7, and install the impact-resistant support members 4. Then, the carbon dioxide fracturing tubes 15 at the arch position are connected in series, and the internal carbon dioxide filling amount is controlled to simulate rock bursts of different energy levels. The carbon dioxide fracturing tubes 15 are activated by the detonator, releasing energy to destroy the concrete body and forming explosive blocks to impact the anchor net support system 7 to test the impact resistance of the anchor net support system 7.

[0042] Spandrel and side wall test phase: During the crown test, the concrete at the spandrel and side wall positions will not be affected due to the presence of the crown partition plate 13. When the test continues, the carbon dioxide fracturing tubes 15 at the spandrel positions are connected in series and detonated to test the bearing capacity of the anchor net support system 7 at the spandrel positions. Then, the rockburst simulation test at the side wall position is repeated to complete the rockburst simulation at all positions in the tunnel.

[0043] After completing the rock burst simulation of the arch crown and the rock burst simulation of the arch spandrel, it is necessary to move the slag truck 51 to the bottom of the impact test bench 1 through the slag track 52, clean the remaining concrete into the slag truck 51, and transport it to the waste storage area for unified placement before conducting subsequent rock burst tests.

[0044] After the test is completed, there is no need to dismantle the outer movable plate 22 of the vault, the outer movable plate 23 of the spandrel and the outer movable plate 24 of the side wall. It is only necessary to reinstall the inner movable plate 31 of the vault, the inner movable plate 32 of the spandrel and the inner movable plate 33 of the side wall of the surrounding rock lower interface system 3 and pour concrete to carry out the next blasting simulation test.

[0045] The above disclosures are only several preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the scope of protection of the present invention.

Claims

1. A protective system bearing performance test device for monitoring the bearing performance of a protective system under the impact load of rock burst blocks, characterized in that: include: The impact test bench comprises two impact-resistant side walls, which are arc-shaped structures, and a plurality of crack-inducing tube installation holes are opened along the arc direction of the impact-resistant side walls; A plurality of carbon dioxide fracturing tubes are correspondingly inserted into the plurality of fracturing tube installation holes; a plurality of partition plates are arranged between the surrounding rock upper interface system and the surrounding rock lower interface system to separate a plurality of independent rock burst simulation test spaces; The surrounding rock upper interface system is arranged between the two impact-resistant side walls and is located near the outer arc position of the two impact-resistant side walls. The surrounding rock upper interface system includes: multiple external movable plates, each of which is an arc-shaped plate, and the multiple external movable plates are spliced ​​together to form an arch bridge structure, and the curvature of the arch bridge structure is consistent with the curvature of the impact-resistant side wall. Concrete grouting holes are opened on the external movable plate at the top position; The surrounding rock lower interface system includes a plurality of inner movable plates. The surrounding rock lower interface system has the same structure as the surrounding rock upper interface system and is arranged between the two impact-resistant side walls, near the inner arc position of the two impact-resistant side walls. The space between the surrounding rock upper interface system and the surrounding rock lower interface system is used for pouring concrete to simulate the restoration of the tunnel structure. The anchor net support system is arranged on the inner wall of the simulated restored tunnel structure.

2. A protective system load-bearing performance test device according to claim 1, characterized in that: It also includes a seismic base, and the impact test bench is arranged on the seismic base.

3. A protective system load-bearing performance test device according to claim 2, characterized in that: It also includes an impact-resistant support member, one end of which is connected to the earthquake-resistant base, and the other end of which is connected to the impact-resistant side wall.

4. A protective system load-bearing performance test device according to claim 3, characterized in that: Also included is a surrounding rock cleaning system, the surrounding rock cleaning system comprising: a slag transport track, arranged on the surface of the seismic-resistant base and below the surrounding rock lower interface system; The slag transport vehicle is arranged on the slag transport track and moves along the slag transport track.

5. A protective system load-bearing performance test device according to claim 1, characterized in that: A shock-absorbing and energy-absorbing layer is provided on the inner side of each outer movable plate of the surrounding rock upper interface system. The shock-absorbing and energy-absorbing layer is filled with sand to improve the ability to absorb blasting vibration energy.

6. A protective system load-bearing performance test device according to claim 1, characterized in that: The anchor net support system includes: Flexible mesh, supported on the inner wall of the tunnel structure; A plurality of anchor rods are inserted into the inner wall of the tunnel structure and used to fix the flexible net.

7. A method for testing the bearing capacity of a protective system, characterized in that: Conducting a test using the test device according to any one of claims 1 to 6 comprises the following steps: Install the test device, install two impact-resistant side walls, the outer movable plate at the bottom, and the inner movable plate at the bottom in sequence, fill the internal space surrounded by the two impact-resistant side walls, the outer movable plate at the bottom, and the inner movable plate at the bottom with concrete, and after the initial setting is completed, continue to install the outer movable plate at the shoulder, the inner movable plate at the shoulder, and a partition plate on the movable plate at the bottom, and fill the concrete again, and after the initial setting, install the outer movable plate at the top, the inner movable plate at the top, and a partition plate on the corresponding shoulder movable plate, and continue to carry out the final concrete pouring work through the concrete grouting holes. During the concrete pouring process of each part, the carbon dioxide fracturing tube is pre-buried in the impact test bench through the fracturing tube installation hole in advance. After the concrete pouring work is completed, it is cured to achieve the target strength; After the concrete solidifies, all the inner movable plates of the surrounding rock interface system are dismantled to restore the real tunnel single-face state; Drill holes into the simulated tunnel's inner wall, install an anchor-net support system, connect CO2-induced fracturing tubes in series at the arch's top, and control the amount of CO2 filling inside to simulate rockbursts of varying energy levels. The tubes are activated by detonators, releasing energy to destroy the concrete and create explosive blocks that impact the anchor-net support system, thereby testing its impact resistance. During the arch crown test, the presence of the partition plate will not affect the concrete at the arch span and side wall positions. When continuing the test, the carbon dioxide fracturing tubes at the arch span position are connected in series. After detonation, the bearing capacity of the anchor net support system at the arch span position is tested. The rockburst simulation test at the side wall position is repeated to complete the rockburst simulation at all positions in the tunnel.

8. A method for testing the load-bearing performance of a protective system according to claim 7, characterized in that: After completing the rock burst simulation of the arch crown and the arch shoulder, the slag truck moves to the bottom of the impact test bench via the slag track, cleans the remaining concrete into the slag truck, and transports it to the waste storage area for unified placement before conducting subsequent rock burst tests.

9. A method for testing the load-bearing performance of a protective system according to claim 7, characterized in that: After the test is completed, the interface system under the surrounding rock will be reinstalled and concrete poured before the next blasting simulation test can be carried out.

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