Tunnel anchor tension loading test device and test method

Abstract

The invention discloses a tunnel anchor tension loading test device and a test method, the device comprises an enclosure model, a steel strand, a tension monitoring device, a loading frame, a tension mechanism, a strain monitoring device, a stress monitoring device and a data analysis system, and the enclosure model is filled with a rock-soil body formed by a surrounding rock material; a tunnel model and an anchorage model are pre-buried in a rock-soil body, one end of the anchorage model is located above the tunnel model, the other end of the anchorage model is located below the tunnel model, a tensioning mechanism is fixed to a reaction frame, the two ends of a steel strand are connected with the anchorage model and the tensioning mechanism respectively, and a tension monitoring device is arranged on the steel strand; and the tension monitoring device, the strain monitoring device and the stress monitoring device are electrically connected with the data analysis system. By monitoring the soil pressure of the rock-soil body and the strain change of the supporting structure in the test process, the influence of tunnel excavation on the anchor plug body under the condition that the tunnel type anchorage and the tunnel space interact can be accurately monitored.

Description

Technical Field

[0001] The invention relates to the technical field of anchor plug model testing, and in particular to a tunnel anchor tension loading testing device and a testing method. Background Art

[0002] Tunnel anchors (abbreviated as tunnel anchors) are used to anchor suspension bridge cables. They are an extremely important anchoring form in the anchoring system of suspension bridges, and are particularly suitable for high and steep rock slopes in the mountainous areas of southwest my country. Tunnel excavation has a great influence on the rock mass strength of tunnel anchors and the reliability of tunnel anchors. However, due to the huge volume of tunnel anchors, they can usually only be studied by scaled tests. Among them, indoor scaled model tests are one of the important means to study tunnel anchors.

[0003] In actual projects, tunnel anchors and tunnel space sometimes interact. If traditional test methods are used, the impact of tunnel excavation on anchor plugs cannot be accurately monitored. Therefore, it is necessary to deeply explore the impact of tunnel construction on adjacent anchors and the impact of surrounding rock stress redistribution caused by anchor tensioning on completed tunnels after project operation. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a tunnel anchor tension loading test device and test method, which can not only provide a large tensile force to realize step-by-step loading test on the anchor, but also keep the load constant after application until the loading test is completed.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, the present invention proposes a tunnel anchor tension loading test device, the key of which is: comprising a retaining model, a steel strand, a tension monitoring device, a loading frame, a tensioning mechanism, a strain monitoring device, a stress monitoring device and a data analysis system, the retaining model is filled with a rock mass formed by surrounding rock materials, a tunnel model and an anchor model are pre-buried in the rock mass, one end of the anchor model is located above the tunnel model and the other end is located below the tunnel model, the tensioning mechanism is fixed on the reaction frame, the two ends of the steel strand are respectively connected to the anchor model and the tensioning mechanism, and the tension monitoring device is arranged on the steel strand;

[0007] The rock and soil body is formed with a first monitoring surface, a second monitoring surface, a third monitoring surface and a fourth monitoring surface along the length direction of the tunnel model, the strain monitoring device is arranged on the tunnel model at the first monitoring surface and the second monitoring surface, the stress monitoring device is arranged between the tunnel model and the anchor model at the first monitoring surface and the second monitoring surface, and the stress monitoring device is arranged on the peripheral side of the anchor model at the third monitoring surface and the fourth monitoring surface;

[0008] The tension monitoring device, strain monitoring device and stress monitoring device are all electrically connected to the data analysis system.

[0009] Furthermore, the loading frame includes a bottom longitudinal beam, a column and a top cross beam, and a column is fixed on each of the two balanced bottom longitudinal beams. The top cross beam spans between the tops of the two columns, and a fixed pulley assembly is fixed on the top cross beam. A mounting bracket is connected between the two bottom longitudinal beams and the two columns, and the tensioning mechanism is fixedly mounted on the mounting bracket. The steel strand is connected to the tensioning mechanism after being folded through the fixed pulley assembly.

[0010] Furthermore, the mounting bracket includes a first mounting beam, two mounting columns and a second mounting beam, the first mounting beam is connected between the two bottom longitudinal beams, the second mounting beam is connected between the two vertical columns, the upper and lower ends of the mounting column are respectively fixedly connected to the first mounting beam and the second mounting beam, and the tensioning mechanism is fixedly installed on the side of the mounting column close to the enclosure model.

[0011] Furthermore, the second mounting crossbeam is in a C-shaped structure, with two ends thereof connected to two columns, and the opening direction of the second mounting crossbeam faces one side of the enclosure model.

[0012] Furthermore, the loading frame also includes a counterweight platform, which is connected between two bottom longitudinal beams on the side away from the enclosure model.

[0013] Furthermore, a bottom cross beam is connected between the two bottom longitudinal beams, and reinforcing ribs are connected between the two sides of the column and the bottom longitudinal beam.

[0014] Furthermore, the tensioning mechanism includes a mounting seat, a winding assembly, and a driving assembly. The mounting seat is fixedly mounted on the loading frame, the winding assembly is fixedly mounted in the mounting seat, the steel strand is fixedly connected to the winding assembly, and the driving assembly is drivingly connected to the winding assembly.

[0015] Furthermore, the driving assembly is a handle or a motor or a jack, and the winding assembly is a self-locking winch.

[0016] Furthermore, the tension monitoring device adopts a tension gauge, the strain monitoring device adopts a strain gauge, and the stress monitoring device adopts an earth pressure cell.

[0017] In a second aspect, the present invention further proposes a tunnel anchor tension loading test method based on the tension loading device, comprising the following steps:

[0018] Step 1: gradually fill the surrounding rock material into the retaining model to form a rock and soil body;

[0019] Step 2: The stress monitoring device is arranged around the anchor model at the third monitoring surface and the fourth monitoring surface, and the anchor model is connected to the steel strand, and then the anchor model is buried in the rock and soil body during the process of filling the surrounding rock material, and the signal line of the stress monitoring device is led out of the surrounding model;

[0020] Step 3: burying the tunnel model in the rock and soil above the anchor model during the process of filling the surrounding rock material, setting the stress monitoring device between the tunnel model and the anchor model at the first monitoring surface and the second monitoring surface, setting the strain monitoring device on the tunnel model at the first monitoring surface and the second monitoring surface, and leading the signal lines of the stress monitoring device and the strain monitoring device out of the surrounding model;

[0021] Step 4: arranging the tension monitoring device on the steel strand, arranging the loading frame on one side of the enclosure model, and connecting the steel strand and the tensioning mechanism fixed on the loading frame;

[0022] Step 5, connecting the signal lines of the stress monitoring device, the stress monitoring device and the strain monitoring device to the data analysis system;

[0023] Step 6: excavate the tunnel, observe and record the stress and strain changes;

[0024] Step 7: After the tunnel is penetrated, the anchor model is tensioned by a tensioning mechanism, and loading is completed by controlling the load size, and the stress and strain changes are collected;

[0025] Step 8: Analyze and plot the collected data using a data analysis system.

[0026] The remarkable effects of the present invention are:

[0027] 1. The present invention first fills the surrounding rock material into the retaining structure to simulate the surrounding rock area, then puts the anchor model and the tunnel into the model, and finally tensions the anchor model and uses a tunneling tool to simulate tunnel excavation. By monitoring the soil pressure of the rock and soil body and the strain changes of the support structure during the test, the stress conditions of the surrounding rock and support during the actual construction process can be accurately simulated, thereby providing theoretical data for the actual project, which is of reference significance for subsequent projects.

[0028] 2. The device provided in the present invention can provide a large tensile force, realize step-by-step loading test on the anchor, and obtain the mechanical properties of the surrounding rock mass under the normal load-bearing state of the anchor model and the mechanical change law of the surrounding rock under the overload state.

[0029] 3. The device provided by the present invention has a simple structure and is easy to operate, and can help to conveniently and quickly implement loading tests on anchors step by step. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the structure of the loading frame and the tensioning mechanism;

[0032] Figure 3 It is a side schematic diagram of the setting position of the stress monitoring device and the strain monitoring device;

[0033] Figure 4 is a top view of the setting positions of the stress monitoring device and the strain monitoring device;

[0034] Figure 5 It is a flow chart of the test method of the present invention.

[0035] Among them, 10 enclosure model, 11 rock and soil body, 12 tunnel model, 13 first monitoring surface, 14 second monitoring surface, 15 third monitoring surface, 16 fourth monitoring surface, 17 anchor model, 20 steel strand, 30 tension monitoring device, 40 loading frame, 41 bottom longitudinal beam, 42 column, 43 top beam, 44 fixed pulley assembly, 45 first installation beam, 46 second installation beam, 47 installation column, 48 counterweight platform, 49 bottom beam, 410 reinforcement rib, 50 tensioning mechanism, 51 mounting seat, 52 winding assembly, 53 driving assembly, 60 strain monitoring device, 70 stress monitoring device, 80 data analysis system. DETAILED DESCRIPTION

[0036] The specific implementation manner and working principle of the present invention are further described in detail below with reference to the accompanying drawings.

[0037] Embodiment 1:

[0038] like Figure 1-Figure 4 As shown, this embodiment proposes a tunnel anchor tension loading test device, including a retaining model 10, a steel strand 20, a tension monitoring device 30, a loading frame 40, a tensioning mechanism 50, a strain monitoring device 60, a stress monitoring device 70 and a data analysis system 80. The retaining model 10 is filled with a rock body 11 formed by surrounding rock materials, and a tunnel model 12 and an anchor model 17 are pre-buried in the rock body 11. One end of the anchor model 17 is located above the tunnel model 12 and the other end is located below the tunnel model 12. 2, wherein the tunnel model 12 is an unexcavated tunnel structure composed of rock and soil in the tunnel and a tunnel lining structure, the anchor model 17 is composed of an anchor plug body and a front anchor chamber lining structure, the tensioning mechanism 50 is fixed on the reaction frame, the two ends of the steel strand 20 are respectively connected to the anchor model 17 and the tensioning mechanism 50, and the tension monitoring device 30 is arranged on the steel strand 20; the tension monitoring device 30, the strain monitoring device 60, and the stress monitoring device 70 are all electrically connected to the data analysis system 80.

[0039] When the above-mentioned device is conducting a tension loading test, the surrounding rock material is first filled into the retaining model 10 to simulate the surrounding rock area to form a rock and soil body 11, and then the tunnel model 12 and the anchor model 17 are placed in the retaining model 10, and then the anchor model is tensioned through the steel strand 20, the tension monitoring device 30, the loading frame 40, and the tensioning mechanism 50, and the tunneling tool is used to simulate the tunnel excavation. The soil pressure and the strain changes of the support structure during the test are monitored by the strain monitoring device 60, the stress monitoring device 70 and the data analysis system 80. It can accurately monitor the impact of tunnel excavation on the anchor body when the tunnel anchor interacts with the tunnel space, and can simulate the stress conditions of the surrounding rock and support during the actual construction process, thereby providing theoretical data for actual engineering.

[0040] See attached Figure 2 The loading frame 40 includes a bottom longitudinal beam 41, a column 42 and a top cross beam 43. A column 42 is fixed on each of the two balanced bottom longitudinal beams 41. The top cross beam 43 spans between the tops of the two columns 42. A fixed pulley assembly 44 is fixed on the top cross beam 43. A mounting bracket is connected between the two bottom longitudinal beams 41 and the two columns 42. The tensioning mechanism 50 is fixedly mounted on the mounting bracket. The steel strand 20 is connected to the tensioning mechanism 50 after being folded by the fixed pulley assembly 44.

[0041] The loading frame 40 of the frame structure is not only simple in structure and easy to manufacture, but also easy to operate during tension loading tests, and can accurately monitor the effect of tunnel excavation on the anchor plug body when the tunnel anchor interacts with the tunnel space.

[0042] Preferably, the mounting bracket includes a first mounting beam 45, two mounting columns 47 and a second mounting beam 46, the first mounting beam 45 is connected between the two bottom longitudinal beams 41, the second mounting beam 46 is connected between the two vertical columns 42, the upper and lower ends of the mounting column 47 are fixedly connected to the first mounting beam 45 and the second mounting beam 46 respectively, and the tensioning mechanism 50 is fixedly installed on the side of the mounting column 47 close to the enclosure model 10.

[0043] The mounting bracket of the above-mentioned structural form is not only simple in structure and easy to manufacture, but also convenient for tensioning operation during tension loading test, which helps to accurately monitor the influence of tunnel excavation on the anchor plug body when the tunnel anchor interacts with the tunnel space.

[0044] In order to facilitate the tension loading experiment and avoid interference between the steel strand 20 and the loading frame 40, the second mounting beam 46 is in a C-shaped structure, with its two ends connected to the two columns 42, and the opening direction of the second mounting beam 46 is toward one side of the enclosure model 10.

[0045] In this embodiment, the loading frame 40 further includes a counterweight platform 48, which is connected between two bottom longitudinal beams 41 on the side away from the enclosure model 10. By setting the counterweight platform 48, a greater tension can be provided in the tension loading experiment, and the loading test of the anchor can be carried out step by step, so as to obtain the mechanical properties of the surrounding rock mass under the normal load-bearing state of the anchor model and the mechanical change law of the surrounding rock under the overload state.

[0046] In order to ensure that the loading frame 40 has a higher structural strength, a bottom cross beam 49 is connected between the two bottom longitudinal beams, and reinforcing ribs 410 are connected between the two sides of the column 42 and the bottom longitudinal beam 41 .

[0047] from Figure 2 It can also be seen that the tensioning mechanism 50 includes a mounting seat 51, a winding assembly 52, and a driving assembly 53. The mounting seat 51 is fixedly mounted on the loading frame 40, the winding assembly 52 is fixedly mounted in the mounting seat 51, the steel strand 20 is fixedly connected to the winding assembly 52, and the driving assembly 53 is drivingly connected to the winding assembly 52.

[0048] Preferably, the driving assembly 53 is a handle, and the winding assembly 52 is a self-locking winch. A manual winch as the tensioning mechanism 50 has a simpler structure, lower implementation cost, and can be implemented without a complex control circuit.

[0049] The tension monitoring device 30 uses a tension gauge, the strain monitoring device 60 uses a strain gauge, and the stress monitoring device 70 uses an earth pressure cell.

[0050] like Figure 3 and Figure 4 As shown, the rock and soil body 11 forms a first monitoring surface 13, a second monitoring surface 14, a third monitoring surface 15 and a fourth monitoring surface 16 along the length direction of the tunnel model 12, the strain monitoring device 60 is arranged on the tunnel model 12 at the first monitoring surface 13 and the second monitoring surface 14, the stress monitoring device 70 is arranged between the tunnel model 12 and the anchor model 17 at the first monitoring surface 13 and the second monitoring surface 14, and the stress monitoring device 70 is arranged on the peripheral side of the anchor model 17 at the third monitoring surface 15 and the fourth monitoring surface 16, and the above-mentioned strain monitoring device 60 and stress monitoring device 70 are electrically connected to the data analysis system 80.

[0051] Furthermore, the first monitoring surface 13 is located at one-sixth to one-fifth of the total length of the enclosure model 10 on the side close to the loading frame 40, the second monitoring surface 14 is located at two-sixths to two-fifths of the total length of the enclosure model 10 on the side close to the loading frame 40, the third monitoring surface 15 is located at three-sixths to three-fifths of the total length of the enclosure model 10 on the side close to the loading frame 40, and the fourth monitoring surface 16 is located at four-sixths to five-sixths of the total length of the enclosure model 10 on the side close to the loading frame 40.

[0052] Arranging the strain monitoring device 60 and the stress monitoring device 70 in the above-mentioned manner and adopting different monitoring methods for different positions can more accurately monitor the soil pressure of the rock and soil mass and the strain changes of the support structure during the tension loading test, that is, more accurately monitor the influence of tunnel excavation on the anchor plug body when the tunnel anchor interacts with the tunnel space, so as to more accurately simulate the stress conditions of the surrounding rock and support during the actual construction process, and then provide theoretical data for the actual project, which is of reference significance for subsequent projects.

[0053] Embodiment 2:

[0054] like Figure 5 As shown, this embodiment proposes a test method based on a tunnel anchor tension loading test device described in the embodiment, and the specific steps are as follows:

[0055] Step 1: gradually fill the surrounding rock material into the retaining model 10 to form a rock and soil body 11;

[0056] Step 2: The stress monitoring device 70, i.e., the earth pressure box, is arranged around the anchor plug body of the anchor model 17 at the third monitoring surface 15 and the fourth monitoring surface 16 to monitor the stress change around the anchor plug body of the anchor model 17;

[0057] The steel strand 20 is passed through the front of the enclosure model 10, the front anchor chamber lining structure of the anchor model 17 and its anchor plug body in sequence, and finally the steel strand 20 is fixed on the rear anchor surface of the anchor plug body;

[0058] The anchor model 17 is buried in the rock mass 11 during the process of filling the surrounding rock material;

[0059] Lead the signal line of the stress monitoring device 70 out of the enclosure model 10;

[0060] Step 3: during the process of filling the surrounding rock material, the tunnel model 12 is buried in the rock mass 11 above the anchor model 17, and the stress monitoring device 70 is arranged in the rock mass 11 between the tunnel model 12 and the anchor model 17 at the first monitoring surface 13 and the second monitoring surface 14 to monitor the stress change of the rock mass between the tunnel and the anchor;

[0061] The strain monitoring device 60 consisting of strain gauges is pasted on the tunnel lining structure of the tunnel model 12 at the first monitoring surface 13 and the second monitoring surface 14 to monitor the strain change of the tunnel model 12;

[0062] Lead the signal lines of the stress monitoring device 70 and the strain monitoring device 60 out of the enclosure model 10;

[0063] Step 4: The tension monitoring device 30 is arranged on the steel strand 20, the loading frame 40 is arranged on one side of the enclosure model 10, and the steel strand 20 is connected to the tensioning mechanism 50 fixed on the loading frame 40;

[0064] Step 5, connecting the stress monitoring device 70, the signal lines of the stress monitoring device 70 and the strain monitoring device 60 to the data analysis system 80;

[0065] Step 6: excavate the tunnel, observe and record the stress and strain changes;

[0066] Step 7: After the tunnel is penetrated, the anchor model 17 is tensioned by the tensioning mechanism 50, and loading is completed by controlling the load size, and the stress and strain changes are collected;

[0067] Step 8: Analyze the collected data using a data analysis system 80 such as EXCEL software and use ORIGIN software to make graphs until the tension test and data analysis are completed.

[0068] The embodiment of the present invention first fills the surrounding rock material into the surrounding structure to simulate the surrounding rock area, then puts the anchor model and the tunnel into the model, and finally tensions the anchor model and uses the tunneling tool to simulate the tunnel excavation. By monitoring the soil pressure of the rock and soil body and the strain changes of the supporting structure during the test, the influence of the tunnel excavation on the anchor plug body under the interaction between the tunnel anchor and the tunnel space can be accurately monitored, and the stress conditions of the surrounding rock and support during the actual construction process can be accurately simulated, thereby providing theoretical data for the actual project, which is of reference significance for subsequent projects. At the same time, the device provided in the present invention can provide a large pulling force, realize the loading test of the anchor step by step, and obtain the mechanical properties of the surrounding rock mass under the normal load-bearing state of the anchor model and the mechanical change law of the surrounding rock under the overload state. In addition, the device provided by the present invention has a simple structure and is easy to operate, which can help to conveniently and quickly realize the loading test of the anchor step by step.

[0069] The technical solution provided by the present invention is described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A tunnel anchor tension loading test device, characterized in that: The invention comprises a retaining model (10), a steel strand (20), a tension monitoring device (30), a loading frame (40), a tensioning mechanism (50), a strain monitoring device (60), a stress monitoring device (70) and a data analysis system (80); the retaining model (10) is filled with a rock mass (11) formed by surrounding rock materials; a tunnel model (12) and an anchor model (17) are pre-buried in the rock mass (11); one end of the anchor model (17) is located above the tunnel model (12) and the other end is located below the tunnel model (12); the tensioning mechanism (50) is fixed on the reaction frame; the two ends of the steel strand (20) are respectively connected to the anchor model (17) and the tensioning mechanism (50); and the tension monitoring device (30) is arranged on the steel strand (20); The rock and soil body (11) is formed with a first monitoring surface (13), a second monitoring surface (14), a third monitoring surface (15) and a fourth monitoring surface (16) along the length direction of the tunnel model (12); the strain monitoring device (60) is arranged on the tunnel model (12) at the first monitoring surface (13) and the second monitoring surface (14); the stress monitoring device (70) is arranged between the tunnel model (12) and the anchor model (17) at the first monitoring surface (13) and the second monitoring surface (14); and the stress monitoring device (70) is arranged on the peripheral side of the anchor model (17) at the third monitoring surface (15) and the fourth monitoring surface (16); The tension monitoring device (30), the strain monitoring device (60), and the stress monitoring device (70) are all electrically connected to the data analysis system (80).

2. The tunnel anchor tension loading test device according to claim 1, characterized in that: The loading frame (40) comprises a bottom longitudinal beam (41), a column (42) and a top cross beam (43). One column (42) is fixed on each of the two balanced bottom longitudinal beams (41). The top cross beam (43) is straddled between the tops of the two columns (42). A fixed pulley assembly (44) is fixed on the top cross beam (43). A mounting bracket is connected between the two bottom longitudinal beams (41) and the two columns (42). The tensioning mechanism (50) is fixedly mounted on the mounting bracket. The steel strand (20) is connected to the tensioning mechanism (50) after being folded around the fixed pulley assembly (44).

3. The tunnel anchor tension loading test device according to claim 2, characterized in that: The mounting bracket comprises a first mounting crossbeam (45), two mounting columns (47) and a second mounting crossbeam (46); the first mounting crossbeam (45) is connected between two bottom longitudinal beams (41); the second mounting crossbeam (46) is connected between two vertical columns (42); the upper and lower ends of the mounting column (47) are respectively fixedly connected to the first mounting crossbeam (45) and the second mounting crossbeam (46); and the tensioning mechanism (50) is fixedly mounted on a side of the mounting column (47) close to the enclosure model (10).

4. The tunnel anchor tension loading test device according to claim 3, characterized in that: The second installation crossbeam (46) is in a C-shaped structure, with two ends thereof connected to two upright posts (42), and the opening direction of the second installation crossbeam (46) faces one side of the enclosure model (10).

5. The tunnel anchor tension loading test device according to claim 2, characterized in that: The loading frame (40) further comprises a counterweight platform (48), which is connected between two bottom longitudinal beams (41) on a side away from the enclosure model (10).

6. The tunnel anchor tension loading test device according to claim 2, characterized in that: A bottom cross beam (49) is also connected between the two bottom longitudinal beams, and reinforcing ribs (410) are connected between the two sides of the upright column (42) and the bottom longitudinal beam (41).

7. The tunnel anchor tension loading test device according to claim 1, characterized in that: The tensioning mechanism (50) comprises a mounting seat (51), a winding assembly (52), and a driving assembly (53); the mounting seat (51) is fixedly mounted on the loading frame (40); the winding assembly (52) is fixedly mounted in the mounting seat (51); the steel strand (20) is fixedly connected to the winding assembly (52); and the driving assembly (53) is drivingly connected to the winding assembly (52).

8. The tunnel anchor tension loading test device according to claim 7, characterized in that: The driving component (53) is a handle, a motor or a jack, and the winding component (52) is a self-locking winch.

9. The tunnel anchor tension loading test device according to any one of claims 1 to 8, characterized in that: The tension monitoring device (30) uses a tension gauge, the strain monitoring device (60) uses a strain gauge, and the stress monitoring device (70) uses an earth pressure cell.

10. A test method based on the tunnel anchor tension loading test device according to any one of claims 1 to 9, characterized in that: The steps include: Step 1: gradually fill the surrounding rock material into the retaining model (10) to form a rock and soil body (11); Step 2: The stress monitoring device (70) is arranged around the anchor model (17) at the third monitoring surface (15) and the fourth monitoring surface (16), and the anchor model (17) is connected to the steel strand (20), and then the anchor model (17) is buried in the rock mass (11) during the process of filling the surrounding rock material, and the signal line of the stress monitoring device (70) is led out of the surrounding model (10); Step 3: during the process of filling the surrounding rock material, bury the tunnel model (12) in the rock mass (11) above the anchor model (17), arrange the stress monitoring device (70) between the tunnel model (12) and the anchor model (17) at the first monitoring surface (13) and the second monitoring surface (14), arrange the strain monitoring device (60) on the tunnel model (12) at the first monitoring surface (13) and the second monitoring surface (14), and lead the signal lines of the stress monitoring device (70) and the strain monitoring device (60) out of the surrounding rock model (10); Step 4: The tension monitoring device (30) is arranged on the steel strand (20), the loading frame (40) is arranged on one side of the enclosure model (10), and the steel strand (20) and the tensioning mechanism (50) fixed on the loading frame (40) are connected; Step 5, connecting the signal lines of the stress monitoring device (70), the stress monitoring device (70) and the strain monitoring device (60) to the data analysis system (80); Step 6: excavate the tunnel, observe and record the stress and strain changes; Step 7: After the tunnel is penetrated, the anchor model (17) is tensioned by the tensioning mechanism (50), and loading is completed by controlling the load size, and the stress and strain changes are collected; Step 8: Analyze and plot the collected data using the data analysis system (80).

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