Variable angle triaxial testing apparatus for simulating cross-tunnel excavation and considering external disturbance

Abstract

The application discloses a variable-angle triaxial test device for simulating cross-tunnel excavation and considering external disturbance, which comprises a counterforce frame, a hydraulic loading module, a vertical disturbance module and a variable-angle triaxial test module arranged on the counterforce frame, lateral confining pressure is applied through first and second horizontal loading oil cylinders, vertical load is applied through a vertical loading oil cylinder, until a set stress state is reached, vertical disturbance to the rock sample is formed by vertically moving the disturbance block along the slide rail, and cross-tunnel excavation simulation is performed on the rock sample through the excavation hole. In the case of realizing the conventional six-surface loading true triaxial test, cross-tunnel excavation is simulated, and disturbance can be applied in the vertical direction, thereby realizing single-hole, cross-double-hole excavation of the rock sample under the true triaxial loading condition and stability analysis of the rock sample under vertical disturbance after the excavation is completed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock indoor test, in particular to a variable angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] Compared with shallow underground engineering, the stress state of deep rock mass is complex and significantly affected by unloading, and the rock mass failure mode has the characteristics of diversity, such as zonal cracking and rock burst. Revealing the unloading disaster evolution mechanism of deep rock mass and the corresponding multi-element precursor evolution law is an important theoretical basis for realizing disaster monitoring and early warning and process control, and indoor test is an important research means.

[0004] Large-scale model test is a common test method for simulating deep rock mass excavation and failure, but this method usually has the disadvantages of long implementation period and high cost, which is not conducive to comparative study of various test conditions, and at present, similar materials are difficult to realize the similarity of hard rock brittleness, and if high-strength brittle rock materials are used, more loading cylinders are needed, which further increases the test cost.

[0005] Although small-scale true triaxial test has low cost and high implementation efficiency, the existing true triaxial loading test technology is difficult to realize the simulation of the real stress path of "loading first and excavation later".

[0006] Taking the construction of deep buried long tunnel as an example, the construction of the main tunnel is usually preceded by the construction of multiple horizontal tunnels perpendicular to the axis direction of the main tunnel, so as to improve the construction speed. However, the stability of the surrounding rock at the connection part of the horizontal tunnel and the main tunnel is relatively poor, and at present, large-scale model tests rarely consider the simulation of the surrounding rock failure process of cross-tunnel, and small-scale rock block tests have not been reported.

[0007] In addition, after the completion of the tunnel construction, the influence of external disturbance on the stability of the tunnel needs to be considered, such as weapon attack, nearby tunnel blasting construction, etc., and the current triaxial test technology still has deficiencies in this regard. SUMMARY

[0008] In order to solve the above problems, the present application provides a variable angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, which can simulate cross-tunnel excavation while applying disturbance in the vertical direction under the condition of realizing traditional six-surface loading true triaxial test.

[0009] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0010] In a first aspect, the present application provides a variable-angle triaxial test device for simulating cross-tunnel excavation and considering external disturbance, comprising: a counterforce frame, a hydraulic loading module, a vertical disturbance module and a variable-angle triaxial test module arranged on the counterforce frame.

[0011] The hydraulic loading oil cylinder comprises a vertical loading oil cylinder arranged on the top of the counterforce frame, and a first horizontal loading oil cylinder and a second horizontal loading oil cylinder arranged on both sides of the counterforce frame.

[0012] The vertical disturbance module comprises a force transmission block, a disturbance block, a sliding rail, a vertical force transmission column and a pressure bearing plate; the top end of the force transmission block is connected with the vertical loading oil cylinder, and the bottom end of the force transmission block is sequentially connected with the disturbance block, the vertical force transmission column and the pressure bearing plate to transmit the vertical load to the pressure bearing plate; the vertical force transmission column is provided with a sliding rail to make the disturbance block vertically move along the sliding rail and form vertical disturbance to the rock sample.

[0013] The variable-angle triaxial test module comprises a bearing device arranged on the bottom of the counterforce frame and a variable-angle triaxial device arranged on the bearing device, and the first horizontal loading oil cylinder and the second horizontal loading oil cylinder are respectively connected with one variable-angle triaxial device; the variable-angle triaxial device comprises a sliding block and a force bearing sliding seat in sliding connection, the sliding block is provided with an excavation hole, and a rock sample is arranged between the two sliding blocks to apply lateral confining pressure through the first horizontal loading oil cylinder and the second horizontal loading oil cylinder, apply vertical load through the vertical loading oil cylinder, until a set stress state is reached, and simulate cross-tunnel excavation through the excavation hole.

[0014] As an optional implementation, the horizontal center line of the rock sample coincides with the horizontal center line of the variable-angle triaxial device and the first horizontal loading oil cylinder and the second horizontal loading oil cylinder.

[0015] As an optional implementation, a comparative force value sensor is arranged on each of the vertical loading oil cylinder, the first horizontal loading oil cylinder and the second horizontal loading oil cylinder to obtain a current force value, and the force value is adjusted according to the difference between the current force value and a required force value, so as to realize loading with different waveforms to disturbance.

[0016] As an optional implementation, the bearing device comprises a bearing platform cushion and a sample bearing platform, the bearing platform cushion is arranged on the bottom of the counterforce frame, the sample bearing platform is arranged on the bearing platform cushion, and the variable-angle triaxial devices and the rock sample on both sides are arranged on the sample bearing platform.

[0017] As an optional implementation, the force bearing sliding seat is provided with a sliding rail and a positioning bolt, the sliding block is provided with a sliding groove matched with the sliding rail and a positioning hole matched with the positioning bolt, the force bearing sliding seat is connected with the sliding block through the sliding rail and the sliding groove to make the sliding block slide along the sliding rail in an arc shape, and the sliding block is fixed in position through the positioning hole and the positioning bolt after the sliding angle is determined.

[0018] As an alternative embodiment, the force bearing sliding seat is provided with a scale.

[0019] As an alternative embodiment, the sliding block is provided with an acoustic emission sensor base for mounting an acoustic emission sensor therein, which is used to monitor the crack condition of the rock during the test.

[0020] In a second aspect, the present application provides a variable-angle triaxial test method for simulating cross-tunnel excavation and considering external load disturbance, which uses the variable-angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance according to the first aspect, and comprises the following steps:

[0021] The bearing pad is installed at the bottom end of the counterforce frame, the sample bearing pad is installed on the bearing pad, the rock sample is placed above the sample bearing pad and is in contact with the sliding block of the variable-angle triaxial device;

[0022] The angle of the sliding block and the force bearing sliding seat is adjusted, and the position is fixed by the positioning bolt;

[0023] After the horizontal center line of the rock sample coincides with the horizontal center lines of the variable-angle triaxial device and the first and second horizontal loading oil cylinders, the pressure plate is installed on the upper surface of the rock sample;

[0024] The acoustic emission sensor is arranged in the acoustic emission sensor base and is attached to the surface of the rock sample, the first and second horizontal loading oil cylinders are started to load to a specific confining pressure value, and then the vertical loading oil cylinder is started to apply a vertical load to the rock sample until a set stress state is reached;

[0025] The cross-chamber is excavated by using a handheld drill through the reserved excavation hole on the sliding block.

[0026] As an alternative embodiment, when considering vertical transient external load disturbance, the disturbance block is controlled to move to the pressure plate, and the vertical disturbance to the rock sample is formed by the mutual impact of the disturbance block and the pressure plate.

[0027] As an alternative embodiment, when considering vertical steady-state external load disturbance, the current force value is obtained according to the comparison force value sensor, the force value is changed according to the working condition requirement, and the stress wave is applied.

[0028] Compared with the prior art, the present application has the following advantages:

[0029] The present application provides a variable-angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, which can simulate cross-tunnel excavation and apply disturbance in the vertical direction while realizing the traditional six-surface loading true triaxial test.

[0030] The present application provides a variable angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, which is based on the variable angle concept, simplifies the loading structure of the test machine, maximally reduces the number of loading oil cylinders, controls the production cost of the test device, improves the test efficiency, and effectively expands the test function of the device.

[0031] The present application provides a variable angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, which is based on the variable angle concept, simplifies the loading structure of the test machine, maximally reduces the number of loading oil cylinders, controls the production cost of the test device, improves the test efficiency, and effectively expands the test function of the device.

[0032] The present application provides a variable angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, which is based on the variable angle concept, simplifies the loading structure of the test machine, maximally reduces the number of loading oil cylinders, controls the production cost of the test device, improves the test efficiency, and effectively expands the test function of the device.

[0033] Advantages of the additional aspects of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0034] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application given below, serve to explain the application, and do not constitute an improper limitation of the application.

[0035] Figure 1 The variable angle triaxial test device structure schematic diagram provided for the present application embodiment 1;

[0036] Figure 2 The variable angle triaxial test device three-dimensional structure schematic diagram provided for the present application embodiment 1;

[0037] Figure 3 The variable angle and double-hole excavation three-dimensional structure schematic diagram provided for the present application embodiment 1 in the true triaxial test;

[0038] Figure 4 The variable angle triaxial device structure schematic diagram provided for the present application embodiment 1;

[0039] Figure 5 The variable angle triaxial device structure schematic diagram provided for the present application embodiment 1 after completing the excavation test.

[0040] 1, counterforce frame, 2, hydraulic loading module, 2-1, vertical loading oil cylinder, 2-2, first horizontal loading oil cylinder, 2-3, second horizontal loading oil cylinder, 3, vertical disturbance module, 3-1, disturbance block, 3-2, slide rail, 3-3, disturbance servo control device, 4, sample bearing platform, 5, bearing platform cushion block, 6, bearing plate, 7, vertical force transmission column, 8, pre-excavation rock sample, 8-1, post-excavation rock sample, 9, variable-angle triaxial device, 9-1, sliding block, 9-2, force-bearing sliding seat, 9-3, positioning bolt, 10, acoustic emission sensor base, 11, excavation hole, 12, force transmission block, 13, comparative force value sensor. DETAILED DESCRIPTION

[0041] The application will be further described below in conjunction with the drawings and examples.

[0042] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0043] It should be noted that the terms used herein are only intended to describe specific embodiments and are not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should also be understood that the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0044] The embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0045] Embodiment 1

[0046] The present embodiment provides a variable-angle triaxial test device for simulating cross-tunnel excavation and considering external load disturbance, comprising: a counterforce frame, and a hydraulic loading module, a vertical disturbance module and a variable-angle triaxial test module arranged on the counterforce frame.

[0047] As shown in Figures 1-2 The counterforce frame 1 includes vertical columns on the left and right sides and horizontal beams on the upper and lower sides, serving as a test site and a counterforce structure; the vertical columns and horizontal beams are integrally welded with high-strength steel plates to ensure that the counterforce frame itself does not deform during the test, meeting the high-precision requirements of the test.

[0048] In the embodiment, the hydraulic loading module 2 comprises hydraulic loading cylinders and corresponding servo hydraulic control systems, which are automatically controlled by computers to apply specific force value loads to the rock sample;

[0049] As shown in Figures 1-2 The hydraulic loading cylinders comprise vertical loading cylinders 2-1 arranged at the top of the counterforce frame and first and second horizontal loading cylinders 2-2 and 2-3 arranged at the two sides of the counterforce frame, which can apply vertical compressive stress and horizontal confining pressure to the rock sample according to specific force values.

[0050] As an alternative embodiment, the three loading cylinders can all achieve a maximum loading force of 2000kN, and the three loading cylinders are controlled by independent servo control systems and different computers, and the different cylinders cooperate with each other to achieve six-sided loading.

[0051] As an alternative embodiment, load sensors are installed on the three loading cylinders to read the size of the applied force value, and the load sensors are connected to the servo hydraulic control system and cooperate with each other to achieve specific force value loading.

[0052] As an alternative embodiment, the first and second horizontal loading cylinders 2-2 and 2-3 have coinciding midlines, so that the loads applied by the loading cylinders on the left and right sides are applied in the middle.

[0053] In the embodiment, as shown in Figures 1-3 The vertical disturbance module 3 comprises a force transmission block 12, a disturbance block 3-1, a sliding rail 3-2, a pressure bearing plate 6, a vertical force transmission column 7, and a disturbance servo control device 3-3.

[0054] The top end of the force transmission block 12 is connected to the vertical loading cylinder 2-1, the bottom end of the force transmission block 12 is connected to the disturbance block 3-1, the disturbance block 3-1 is connected to the pressure bearing plate 6 through the vertical force transmission column 7, the vertical force transmission column 7 is provided with the sliding rail 3-2, and the disturbance block 3-1 moves vertically along the sliding rail 3-2.

[0055] The force transmission block 12 is used to transmit the vertical force value load to the pressure bearing plate 6.

[0056] At the beginning of the test, the disturbance block 3-1 is located at the top end of the sliding rail 3-2, and the disturbance block 3-1 is controlled to vertically slide on the sliding rail 3-2 by the disturbance servo control device 3-3, and the mutual impact of the disturbance block 3-1 and the pressure bearing plate 6 forms vertical disturbance to the rock sample.

[0057] In the embodiment, when the specified force value is loaded in the test, disturbance wave is applied according to the requirements of the working condition and the test scheme.

[0058] The current force value is obtained by using the comparative force value sensor 13 arranged on the vertical loading oil cylinder 2-1, the first horizontal loading oil cylinder 2-2 and the second horizontal loading oil cylinder 2-3;

[0059] According to the difference between the current force value and the required force value, the loading oil cylinder is controlled to load by using the execution motor, so as to adjust the force value, so as to realize the application of stress waves and achieve the loading of different waveforms to the disturbance;

[0060] The stress wave type can currently realize basic waveforms such as sine wave and square wave according to the execution speed of the oil cylinder.

[0061] In the embodiment, the variable-angle triaxial test module comprises a bearing device composed of a bearing pad 5 and a sample bearing platform 4 and a variable-angle triaxial device 9 arranged on the bearing device; the bearing pad 5 is arranged at the bottom of the counterforce frame 1, the sample bearing platform 4 is arranged on the bearing pad 5, the first horizontal loading oil cylinder and the second horizontal loading oil cylinder are respectively connected with one variable-angle triaxial device 9, a rock sample is arranged between the two variable-angle triaxial devices 9, and the rock sample and the variable-angle triaxial device 9 are arranged on the sample bearing platform 4.

[0062] In the embodiment, the variable-angle triaxial device 9 comprises a sliding block 9-1 and a bearing sliding seat 9-2, and the sliding block 9-1 and the bearing sliding seat 9-2 are slidingly connected; specifically:

[0063] The inner surface of the bearing sliding seat 9-2 is provided with a sliding rail and a positioning bolt 9-3, and the outer side surface of the bearing sliding seat 9-2 is provided with a scale;

[0064] The sliding block 9-1 is provided with a sliding groove matched with the sliding rail and a positioning hole matched with the positioning bolt 9-3;

[0065] The bearing sliding seat 9-2 is connected with the sliding groove through the sliding rail, so that the sliding block 9-1 slides along the sliding rail in an arc shape;

[0066] After the sliding block 9-1 determines the sliding angle through the arc sliding, the position is fixed through the cooperation of the positioning hole and the positioning bolt 9-3.

[0067] In the embodiment, a rock sample is arranged between the two sliding blocks 9-1, and the rock sample is attached to the pressure bearing plate 6.

[0068] In the embodiment, the sliding block 9-1 is provided with a digging hole 11, and the digging hole can be used to dig a tunnel by using a handheld drill, such as Figures 4-5 The rock sample 8 before excavation and the rock sample 8-1 after excavation are shown.

[0069] In the embodiment, the sliding block 9-1 is provided with an acoustic emission sensor seat, and an acoustic emission sensor is installed in the acoustic emission sensor seat, which is used to monitor the expansion and penetration of rock cracks in the test.

[0070] Embodiment 2

[0071] The embodiment provides a test method of a variable-angle triaxial test device simulating cross-tunnel excavation and considering external load disturbance, comprising: a variable-angle triaxial double-hole excavation and vertical disturbance test of a rock sample, specifically:

[0072] (1) a complete cubic rock sample is used;

[0073] (2) the bearing platform cushion 5 is installed at the bottom end of the counterforce frame, the test sample bearing platform 4 is installed on the bearing platform cushion 5, the rock sample is placed above the test sample bearing platform 4 and is attached to the sliding block 9-1 of the variable-angle triaxial device 9, the angle between the sliding block 9-1 and the bearing sliding seat 9-2 is adjusted, and the relative positions of the sliding block 9-1 and the bearing sliding seat 9-2 are fixed through positioning bolts;

[0074] (3) after the horizontal center line of the rock sample is coincided with the horizontal center lines of the variable-angle triaxial device and the first horizontal loading oil cylinder 2-2 and the second horizontal loading oil cylinder 2-3, the bearing plate 6 is installed on the upper surface of the rock sample, the sliding rail 3-2 is installed, and appropriate disturbance blocks 3-1 are selected, and vaseline is applied on the sliding rail 3-2 track to reduce the friction generated when the disturbance blocks 3-1 move on the sliding rail 3-2;

[0075] (4) the acoustic emission sensor is arranged in the reserved acoustic emission sensor seat 10 and is attached to the surface of the rock sample, after the first horizontal loading oil cylinder 2-2 and the second horizontal loading oil cylinder 2-3 are loaded to a specific confining pressure value, the vertical loading oil cylinder 2-1 is started to apply a vertical load to the rock sample until a set stress state is reached;

[0076] (5) the cross-hole excavation is performed by using a handheld drill through the reserved excavation hole 11 on the sliding block, and the deformation and failure of surrounding rock in the process of hole construction are analyzed by using monitoring equipment such as an acoustic emission sensor, a three-dimensional laser scanner and a high-definition camera.

[0077] (6) when the vertical transient external load disturbance is considered, the disturbance servo control device is operated by using a computer, the disturbance blocks 3-1 are moved to the bearing plate 6, the vertical disturbance of the rock sample is formed through the mutual impact of the disturbance blocks 3-1 and the bearing plate 6, and the stability of the surrounding rock under the transient external load disturbance is analyzed.

[0078] (7) when the vertical steady-state external load disturbance is considered, the current force value is obtained according to the comparison force sensor, the force value is changed according to the working condition, the oil cylinder loading is controlled, the stress wave is applied, and the stability of the surrounding rock under the steady-state external load disturbance is analyzed.

[0079] In the embodiment, when considering external load disturbance, the movement of the disturbance block is realized by computer controlling the disturbance servo control device to achieve different categories of vertical disturbance. A comparison force value sensor is installed at each of the three oil cylinders, and according to the test working condition, the current force value is compared with the required force value, and the difference is changed by the comparison force value sensor. The difference value is transmitted to the control computer, and after the control computer obtains the difference value, the required force value is transmitted to the execution motor according to the working condition, so as to realize the disturbance of different waveforms, and further analyze the stability of the tunnel surrounding rock under external load disturbance.

[0080] The above describes the specific embodiments of the application in combination with the drawings, but is not a limitation on the protection scope of the application. Those skilled in the art should understand that various modifications or changes made by those skilled in the art on the basis of the technical solutions of the application without creative labor are still within the protection scope of the application.

Claims

1. A variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances, characterized in that, include: The reaction frame, and the hydraulic loading module, vertical disturbance module and variable angle triaxial test module mounted on the reaction frame; The hydraulic loading module includes a hydraulic loading cylinder and a corresponding servo hydraulic control system, which is automatically controlled by a computer to apply a specific force load to the rock sample; the hydraulic loading cylinder includes a vertical loading cylinder located at the top of the reaction frame, and a first horizontal loading cylinder and a second horizontal loading cylinder located on both sides of the reaction frame. The vertical disturbance module includes a force transmission block, a disturbance block, a slide rail, a vertical force transmission column, and a pressure plate. The top of the force transmission block is connected to a vertical loading cylinder, and the bottom of the force transmission block is connected to the disturbance block, the vertical force transmission column, and the pressure plate in sequence to transfer the vertical load to the pressure plate. The vertical force transmission column is equipped with a slide rail so that the disturbance block can move vertically along the slide rail and form a vertical disturbance on the rock sample. The variable angle triaxial test module includes a bearing device located at the bottom of the reaction frame and a variable angle triaxial device located on the bearing device. The first horizontal loading cylinder and the second horizontal loading cylinder are respectively connected to a variable angle triaxial device. The variable angle triaxial device includes a sliding block and a load-bearing sliding seat that are slidably connected. The sliding block is provided with an excavation hole, and a rock sample is placed between the two sliding blocks. Lateral confining pressure is applied by the first horizontal loading cylinder and the second horizontal loading cylinder, and vertical load is applied by the vertical loading cylinder until the set stress state is reached. The rock sample is then subjected to cross tunnel excavation simulation through the excavation hole. The rock sample is a complete cubic rock sample; the horizontal centerline of the rock sample coincides with the horizontal centerline of the variable angle triaxial device, the first horizontal loading cylinder, and the second horizontal loading cylinder; The sliding block is provided with excavation holes. Using the pre-reserved excavation holes on the sliding block, a handheld drilling rig is used to excavate the cross tunnel.

2. The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 1, characterized in that, Each of the vertical loading cylinder, the first horizontal loading cylinder, and the second horizontal loading cylinder is equipped with a comparative force sensor to obtain the current force value. The force value is then adjusted based on the difference between the current force value and the required force value, thereby achieving loading disturbances with different waveforms.

3. The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 2, characterized in that, The bearing device includes a base block and a sample base. The base block is located at the bottom of the reaction frame, and the sample base is located on the base block. The variable angle triaxial device and the rock sample are located on the sample base on both sides.

4. The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 3, characterized in that, The load-bearing sliding seat is provided with a slide rail and a positioning bolt. The sliding block is provided with a sliding groove that matches the slide rail and a positioning hole that matches the positioning bolt. The load-bearing sliding seat is connected to the sliding groove through the slide rail so that the sliding block slides in an arc along the slide rail. After the sliding angle of the sliding block is determined, the position is fixed by the positioning hole and the positioning bolt.

5. The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 4, characterized in that, The load-bearing sliding seat is equipped with a scale.

6. The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 5, characterized in that, The sliding block is equipped with an acoustic emission sensor base for installing an acoustic emission sensor in the acoustic emission sensor base to monitor the cracking of the rock during the test.

7. A variable-angle triaxial test method for simulating the excavation of intersecting tunnels and considering external load disturbances, characterized in that, The variable-angle triaxial test apparatus for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 6 includes: Install the base plate block to the bottom of the reaction frame, install the sample base onto the base plate block, place the rock sample above the sample base, and make it fit with the sliding block of the variable angle triaxial device. Adjust the angle between the sliding block and the load-bearing sliding seat, and fix the position using the positioning bolts; After the horizontal centerline of the rock sample coincides with the horizontal centerline of the variable angle triaxial device, the first horizontal loading cylinder, and the second horizontal loading cylinder, the pressure plate is installed on the upper surface of the rock sample. An acoustic emission sensor is placed in the acoustic emission sensor base and attached to the surface of the rock sample. After the first and second horizontal loading cylinders are activated to load to a specific confining pressure value, the vertical loading cylinder is activated to apply a vertical load to the rock sample until the set stress state is reached. Using the pre-drilled holes on the sliding block, a handheld drilling rig was used to excavate the cross tunnel.

8. The variable-angle triaxial test method for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 7, characterized in that, When considering vertical transient external load disturbance, the disturbance block is controlled to move to the bearing plate, and the vertical disturbance of the rock sample is formed by the mutual collision between the disturbance block and the bearing plate.

9. The variable-angle triaxial test method for simulating the excavation of intersecting tunnels and considering external load disturbances as described in claim 7, characterized in that, When considering vertical steady-state external load disturbances, the current force value is obtained from the comparative force sensor, and the force value is changed according to the working conditions to apply stress waves.

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