Layered rock mass tunnel failure mode experimental device and experimental method

Abstract

The invention relates to a stratified rock mass tunnel failure mode experiment device and method, and belongs to the field of tunnel engineering experiments.The stratified rock mass tunnel failure mode experiment device comprises a reaction frame, jacks are fixedly arranged on the periphery of the inner side of the reaction frame, and the telescopic ends of the jacks point to the geometric center of the reaction frame and are fixedly provided with reaction steel plates; the layered rock mass test piece is placed between the counter-force steel plates, and a distributed optical fiber sensor is arranged in the layered rock mass test piece; a jacking device is arranged on one side of the counter-force frame, and a high-speed camera is arranged on the other side, opposite to the jacking device, of the counter-force frame. The stratified rock mass damage experiment device has the advantages that the stratified rock mass test piece is placed between the counter-force steel plates, the stratified rock mass test piece is subjected to an extrusion damage experiment through the jacking equipment and the jack, the high-speed camera records, an experimenter can conveniently research the damage law of the stratified rock mass, operation is easy, obtained data are more diversified and more visual, and the experiment efficiency is improved. The mechanical behavior and the failure mode in the whole process of tunnel excavation and failure in the stratified rock mass can be judged in all directions.

Description

Technical Field

[0001] The invention relates to the field of tunnel engineering experiments, and in particular to a layered rock mass tunnel failure mode experimental device and an experimental method. Background Art

[0002] After a long process of diagenesis and tectonic movement, the rock mass will produce a large number of discontinuous structural planes, such as bedding planes, and the existence of bedding planes will have a great impact on the failure mode after tunnel excavation. Therefore, it is necessary to study the failure behavior of tunnels under bedding planes.

[0003] At present, strain gauges are often used to monitor the deformation characteristics of tunnel linings in the study of tunnel failure modes. However, the adhesive used in the strain gauges will have a certain impact on the deformation of the lining parts, and the strain gauges usually need to be distributed, which cannot fully reflect the stress and deformation characteristics of the lining. For surrounding rock deformation, more and more scholars have begun to use distributed optical fiber sensors, which are buried in the surrounding rock body during pouring. However, too many optical fibers in the surrounding rock body will increase the tensile strength of the rock material, resulting in serious distortion of the deformation and failure morphology of the surrounding rock material. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a layered rock tunnel failure mode experimental device and an experimental method with more diverse test data and more accurate test results.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: a layered rock mass tunnel failure mode experimental device, comprising a frame-shaped reaction frame, jacks are fixedly arranged on all four sides of the inner side of the reaction frame, the telescopic ends of the jacks point to the geometric center of the reaction frame and are fixedly provided with reaction steel plates, a layered rock mass specimen is placed between the reaction steel plates, and a distributed optical fiber sensor is arranged in the layered rock mass specimen;

[0006] A jacking device is arranged on one side of the reaction frame, a telescopic end of the jacking device extends into the reaction frame and contacts the layered rock specimen, and a high-speed camera is arranged on the other side of the reaction frame relative to the jacking device.

[0007] The beneficial effects of the present invention are as follows: a layered rock specimen is placed between reaction steel plates, an extrusion failure experiment is performed on the layered rock specimen by means of jacking equipment and a jack, and a high-speed camera is used to record the experiment, so that it is convenient for experimenters to study the failure law of the layered rock mass. The operation is simple, and the data obtained are more diverse and intuitive, so that the mechanical behavior and failure mode of the entire process of tunnel excavation and failure in the layered rock mass can be judged in all aspects.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, a lifting bracket is arranged below the jacking equipment.

[0010] The beneficial effect of adopting the above further solution is that the height of the jacking equipment can be adjusted to adapt to layered rock specimens of different sizes.

[0011] An experimental method, using a layered rock tunnel failure mode experimental device to conduct an experiment, comprises the following steps:

[0012] S1. Make two or more partitions and depict the bedding surface characteristics on both sides of the partition according to the JRC coefficient of the bedding surface of the on-site rock mass;

[0013] S2. A layered rock specimen model box with an open top is prepared, and a tunnel model column and two or more mutually parallel partitions are vertically placed in the layered rock specimen model box. The number of partitions is N, and the partitions divide the layered rock specimen model box into N+1 chambers;

[0014] S3, first pouring: select a number of cavities at intervals, use gypsum slurry to pour the batch of cavities, and after the gypsum is initially set, remove all partitions in the layered rock specimen model box;

[0015] S4, burying a number of distributed optical fiber sensors on both sides of the gypsum board formed by the first pouring;

[0016] S5. Second pouring: Use gypsum slurry to pour all the remaining cavities. After the gypsum is initially set, remove the tunnel model column;

[0017] S6. The third pouring: using gypsum slurry to pour the cavity after removing the tunnel model column, and obtaining a layered rock mass specimen after solidification;

[0018] S7. Take out the layered rock specimen and place it in the reaction frame, ensure that the axis of the third pouring part is parallel to the ground, set the preload pressure of the jacks around it according to the stress conditions of the rock mass on site, restore the stress conditions on site and fix the layered rock specimen through the reaction steel plate;

[0019] S8. Arrange the jacking equipment on one side of the layered rock specimen, adjust the jacking position to the third pouring position, set parameters such as drilling speed, and ensure that the drilling distance is greater than the thickness of the layered rock specimen;

[0020] S9, placing a high-speed camera on the other side of the layered rock specimen, and adjusting the angle and position of the high-speed camera so that its photographic range completely covers the layered rock specimen;

[0021] S10, connect several distributed optical fiber sensors to the data acquisition terminal, make preparations for debugging, and set parameters such as acquisition frequency;

[0022] S11. Arrange several acoustic emission instruments in one corner of the layered rock specimen;

[0023] S12, start the high-speed camera, distributed optical fiber sensor and acoustic emission instrument, load the surrounding jacks to the target load, and start the jacking equipment to push the third pouring part until the third pouring part is completely separated from the layered rock mass specimen. During the jacking process, check the collection status of each monitoring instrument at all times. If an abnormal situation occurs, stop drilling and adjust the parameters in time;

[0024] S13. After the jacking is completed, the jacks on all sides are pressurized multiple times in stages. After the target load is reached, the load is held for a period of time. After the information recording is completed and there is no abnormality, the next stage of loading is continued. The holding time for each time is at least 5 minutes, and the loading is stopped until the layered rock specimen is obviously damaged;

[0025] S14. The images in the high-speed camera are transmitted to the DIC equipment for the experimenters to view the change law of the tunnel surrounding rock stress field during the tunnel drilling, loading and destruction process. The data is transmitted by the distributed optical fiber sensor to view the displacement of the deep rock mass along the bedding structure surface. The number of surrounding rock cracks generated at different stages is analyzed by the acoustic emission instrument data, and summarized as the final experimental data.

[0026] The beneficial effects of adopting the above technical solution are: it is possible to manufacture layered rock specimens with multi-layer bedding surface characteristics, and to carry out destructive experiments on the layered rock specimens, and to collect data in all directions with the help of high-speed cameras, distributed optical fiber sensors and acoustic emission instruments, and to verify each other to improve data accuracy, so as to be able to comprehensively judge the mechanical behavior and failure mode of the entire process of tunnel excavation and failure in layered rock.

[0027] Furthermore, before executing step S7, white paint is sprayed on the surface of the layered rock specimen, and black scattered spots are evenly arranged on the surface of the layered rock specimen.

[0028] The beneficial effect of adopting the above further scheme is that when conducting a layered rock specimen destruction test, the degree of deformation of the specimen surface can be judged by the displacement of the black scattered spots.

[0029] Furthermore, before executing step S6, lubricant is applied in the cavity formed by removing the tunnel model column.

[0030] The beneficial effect of adopting the above further solution is to prevent the jamming during the pushing of the third pouring part, thereby affecting the experimental progress. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the layered rock tunnel failure mode experimental device of the present invention.

[0032] Figure 2This is a schematic diagram of the first pouring of the layered rock specimen model box of the present invention.

[0033] Figure 3 It is a schematic diagram of the second pouring of the layered rock specimen model box of the present invention.

[0034] Figure 4 It is a schematic diagram of the third pouring of the layered rock specimen model box of the present invention.

[0035] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0036] 1. Reaction frame; 2. Jack; 3. Reaction steel plate; 4. Jacking equipment; 5. High-speed camera; 6. Lifting bracket; 7. Partition; 8. Layered rock specimen model box; 9. Tunnel model column; 10. Chamber; 11. Layered rock specimen. DETAILED DESCRIPTION

[0037] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0038] Example 1

[0039] like Figure 1 As shown, a layered rock mass tunnel failure mode experimental device comprises a frame-shaped reaction frame 1, jacks 2 are fixedly arranged on all sides of the inner side of the reaction frame 1, the telescopic ends of the jacks 2 point to the geometric center of the reaction frame 1 and are fixedly provided with reaction steel plates 3, a layered rock mass specimen 11 is placed between the reaction steel plates 3, and a distributed optical fiber sensor is arranged in the layered rock mass specimen 11;

[0040] A jacking device 4 is provided on one side of the reaction frame 1 , and the telescopic end of the jacking device 4 extends into the reaction frame 1 and contacts the layered rock specimen 11 . A high-speed camera 5 is provided on the other side of the reaction frame 1 relative to the jacking device 4 .

[0041] The beneficial effects of the present invention are as follows: a layered rock specimen 11 is placed between reaction steel plates 3, an extrusion failure experiment is performed on the layered rock specimen 11 by means of a jacking device 4 and a jack 2, and a high-speed camera 5 is used to record the experiment, so that it is convenient for experimenters to study the failure law of the layered rock mass, the operation is simple, the data obtained are more diverse and intuitive, and the mechanical behavior and failure mode of the entire process of tunnel excavation and failure in the layered rock mass can be comprehensively judged.

[0042] In this embodiment, the layered rock mass refers to sedimentary rock, parametamorphic rock and volcanic rock with a layered structure. In the layered rock mass, the layer and foliation are its main structural surfaces, and the main forms of deformation and failure of the layered rock mass include bending deformation, shear deformation and sliding deformation. In underground projects such as tunnels and underground powerhouses, once the layered rock mass is destroyed, it will cause huge economic losses.

[0043] In this scheme, the layered rock mass specimen 11 needs to be made according to the bedding surface at the tunnel construction site to ensure the accuracy of the experimental data. The frame-shaped reaction frame 1 is placed vertically on the ground. Three jacks 2 are installed in each direction inside the reaction frame 1. The telescopic ends of the jacks 2 are fixed with reaction steel plates 3. The reaction steel plates 3 in four directions are assembled into a frame shape to fix the layered rock mass specimen 11 inside.

[0044] The jacks 2 on all sides can be controlled to expand and contract respectively. The reaction steel plate 3 is used to transmit pressure, reduce pressure, and prevent the expansion end of the jack 2 from directly crushing the layered rock specimen 11. The reaction steel plate 3 has a certain elasticity. When the jack 2 is pushed out, the reaction steel plate 3 is deformed and squeezes the layered rock specimen 11 to perform a destructive experiment. The high-speed camera 5 collects data, and the distributed optical fiber sensor collects data on the displacement of the rock layer.

[0045] Specifically, the high-speed camera 5 is a type of industrial camera with high image stability, high transmission capacity and high anti-interference ability; the distributed optical fiber sensor is a sensor that uses a unique distributed optical fiber detection technology to measure or monitor the spatial distribution and time-varying information along the optical fiber transmission path. It arranges the sensing optical fiber along the field, and can simultaneously obtain the spatial distribution and time-varying information of the measured field.

[0046] As a parallel technical solution of this embodiment, the jack 2 can be replaced by a telescopic cylinder or other telescopic equipment.

[0047] Example 2

[0048] like Figure 1 As shown, preferably, on the basis of Example 1, a lifting bracket 6 is provided below the jacking device 4 .

[0049] The beneficial effect of adopting the preferred solution in the above embodiment is that the height of the jacking device 4 can be adjusted to adapt to layered rock specimens 11 of different sizes.

[0050] Specifically, the lifting bracket 6 includes a base and a column. The base is placed on the ground, and the column is vertically arranged above the base. The column can be a threaded column, which is threadedly connected to the base and can be lifted and lowered by turning the thread. The column can also be a pneumatic telescopic column, which can be lifted and lowered by pneumatic control.

[0051] Example 3

[0052] like Figures 2 to 4 As shown, preferably, based on Example 1-2, an experimental method is used to conduct an experiment using a layered rock tunnel failure mode experimental device, comprising the following steps:

[0053] S1. Make two or more partitions 7, and depict the bedding surface characteristics on both sides of the partition 7 according to the JRC coefficient of the bedding surface of the on-site rock mass;

[0054] S2, making a layered rock specimen model box 8 with an open top, vertically placing a tunnel model column 9 and two or more mutually parallel partitions 7 in the layered rock specimen model box 8, assuming that the number of partitions 7 is N, and the partitions 7 divide the layered rock specimen model box 8 into N+1 chambers 10;

[0055] S3, first pouring: select a number of chambers 10 at intervals, use gypsum slurry to pour the batch of chambers 10, and after the gypsum is initially set, remove all partitions 7 in the layered rock specimen model box 8;

[0056] S4, burying a number of distributed optical fiber sensors on both sides of the gypsum board formed by the first pouring;

[0057] S5, second pouring: pouring all remaining chambers 10 with gypsum slurry, and removing the tunnel model column 9 after the gypsum is initially set;

[0058] S6, third pouring: using gypsum slurry to pour the cavity after removing the tunnel model column 9, and obtaining a layered rock mass specimen 11 after solidification;

[0059] S7, take out the layered rock specimen 11 and place it in the reaction frame 1, ensure that the axis of the third pouring part is parallel to the ground, set the preload pressure of the jacks 2 around it according to the stress conditions of the rock mass on site, restore the stress conditions on site and fix the layered rock specimen through the reaction steel plate 3;

[0060] S8, arranging the jacking device 4 on one side of the layered rock mass specimen 11, adjusting the jacking position to the third pouring position, setting parameters such as the drilling speed, and ensuring that the drilling distance is greater than the thickness of the layered rock mass specimen 11;

[0061] S9, placing the high-speed camera 5 on the other side of the layered rock specimen 11, and adjusting the angle and position of the high-speed camera 5 so that its photographic range completely covers the layered rock specimen 11;

[0062] S10, connect several distributed optical fiber sensors to the data acquisition terminal, make preparations for debugging, and set parameters such as acquisition frequency;

[0063] S11. Arrange several acoustic emission instruments in a corner of the layered rock specimen 11;

[0064] S12, start the high-speed camera 5, the distributed optical fiber sensor and the acoustic emission instrument, load the surrounding jacks 2 to the target load, and the jacking device 4 starts to push the third pouring part until the third pouring part is completely separated from the layered rock specimen 11. During the jacking process, check the collection status of each monitoring instrument at all times, and stop drilling and adjust parameters in time when an abnormal situation occurs;

[0065] S13, after the jacking is completed, the jacks 2 on all sides are pressurized for multiple times in stages, and after loading to the target load, the load is held for a period of time. After the recording of various information is completed and there is no abnormality, the next stage of loading is continued. The holding time for each time is at least 5 minutes, until the layered rock specimen 11 is obviously damaged;

[0066] S14, the images in the high-speed camera 5 are transmitted to the DIC device for the experimenters to view the change law of the tunnel surrounding rock stress field during the tunnel drilling, loading and destruction process, and the displacement of the deep rock mass along the bedding structure surface is viewed through the data transmitted by the distributed optical fiber sensor. The number of surrounding rock cracks generated at different stages is analyzed through the data of the acoustic emission instrument, and summarized as the final experimental data.

[0067] The beneficial effects of adopting the above technical solution are: it is possible to manufacture a layered rock specimen 11 with multi-layer bedding surface characteristics, and to carry out a destructive experiment on the layered rock specimen 11, and to collect data in all directions with the help of a high-speed camera 5, a distributed optical fiber sensor and an acoustic emission instrument, and to verify each other to improve data accuracy, so as to be able to comprehensively judge the mechanical behavior and failure mode of the entire process of tunnel excavation and failure in the layered rock mass.

[0068] In this embodiment, the JRC coefficient (Joint Roughness Coefficient) refers to the surface roughness of rock joints. After the construction personnel detect the rock layer surface structure at the tunnel construction site, they make the corresponding partition 7;

[0069] The inner walls of the layered rock specimen model box 8 on both sides are symmetrically provided with slots, which are perpendicular to the top surface of the layered rock specimen model box 8. The partition 7 is inserted into the slots from the top of the layered rock specimen model box 8 to divide the layered rock specimen model box 8 into a plurality of chambers 10, each chamber 10 being equivalent to a rock layer.

[0070] The cross-section of the tunnel model column 9 is horseshoe-shaped, which simulates the real situation to the maximum extent. The tunnel model column 9 has two placement methods. Method 1: Place it in any chamber 10. After pouring, the tunnel is located in this rock layer; Method 2: Break a partition 7, and place the tunnel model column 9 at the broken position of the partition 7. The tunnel model column 9 is located between two chambers 10. After pouring, the tunnel is located between two rock layers at the same time, and different stress conditions can be tested.

[0071] like Figure 2 As shown, a batch of chambers 10 are first cast at intervals, and all the partitions 7 are removed after the gypsum solidifies. After the partitions 7 are removed, the solidified gypsum board can still divide the layered rock specimen model box 8 into a number of chambers 10, and both sides of the solidified gypsum board have undulating bedding surface characteristics. At this time, a distributed optical fiber sensor is buried in some bedding surfaces that need to be tested to minimize the influence of the distributed optical fiber sensor on the tensile strength of the layered rock specimen 11;

[0072] Then as Figure 3 As shown, a second pouring is performed, and new gypsum slurry is poured between two solidified gypsum boards. The gypsum slurry is closely combined with the bedding surface characteristics of the side of the gypsum board after the first pouring to simulate the actual rock layer. After solidification, the tunnel model column 9 is removed;

[0073] Then as Figure 4 As shown, the third pouring is carried out, and the gypsum slurry fills the holes exposed after the tunnel model column 9 is removed, and the layered rock specimen 11 is completed after solidification.

[0074] After that, the layered rock specimen 11 is taken out from the layered rock specimen model box 8 and placed in the reaction steel plate 3, and then the jack 2 clamps the layered rock specimen 11, and the jacking device 4 is started to align with the third pouring position, and the jacking device 4 gradually pushes the gypsum column of the third pouring part out of the layered rock specimen 11, and then according to the on-site rock stress distribution, the jacks 2 on all sides are controlled to be partially or fully extended to squeeze the layered rock specimen 11;

[0075] In this process, when the material to be tested is deformed or moved, sound waves will be generated. The acoustic emission instrument is an instrument used to detect, record, analyze the acoustic emission signals and use the acoustic emission signals to infer the acoustic emission source, while the high-speed camera 5 takes pictures of the surface deformation, and the distributed optical fiber sensor senses the displacement of the rock layer simulated by the gypsum board. Through the above equipment, detection is carried out from multiple fields and summarized into experimental data;

[0076] Among them, DIC equipment (Digital Image Correlat ion, digital image correlation technology) is mainly used to measure the deformation and strain of the surface of an object. It is an algorithm that compares related points of an image. Through this method, the displacement and strain distribution of the surface of an object can be calculated;

[0077] The distributed optical fiber sensor and the data acquisition terminal may be connected by wire or by wireless transmission, thereby reducing the impact on the layered rock specimen 11 .

[0078] Example 4

[0079] like Figures 2 to 4As shown, preferably, on the basis of Embodiments 1-3, before executing step S7, white paint is sprayed on the surface of the layered rock specimen 11, and black scattered spots are evenly arranged on the surface of the layered rock specimen 11.

[0080] The beneficial effect of adopting the preferred solution in the above embodiment is that when conducting a destruction test on a layered rock specimen 11, the degree of deformation of the specimen surface can be determined by the displacement of the black scattered spots.

[0081] Specifically, by pre-spraying white paint to form a base color, and then spraying black spots, it will be more conspicuous, and multiple black spots will form a grid. Once the layered rock specimen 11 is squeezed and deformed, the observation will be more intuitive, and it will be easier to judge the deformation amount, reducing the difficulty of the experiment.

[0082] Example 5

[0083] like Figures 2 to 4 As shown, preferably, on the basis of Embodiments 1-4, before executing step S6, a lubricant is applied to the cavity formed by removing the tunnel model column 9.

[0084] The beneficial effect of adopting the preferred solution in the above embodiment is to prevent jamming when pushing the third pouring part, thereby affecting the experimental progress.

[0085] In this embodiment, the lubricant may be vaseline, talcum powder or any other type of lubricant.

[0086] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0087] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0088] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0089] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0090] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0091] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A layered rock tunnel failure mode experimental device, characterized in that: The invention comprises a frame-shaped reaction frame (1), wherein jacks (2) are fixedly arranged on all four sides of the inner side of the reaction frame (1), the telescopic ends of the jacks (2) point to the geometric center of the reaction frame (1) and are fixedly provided with reaction steel plates (3), a layered rock mass specimen (11) is placed between the reaction steel plates (3), and a distributed optical fiber sensor is arranged in the layered rock mass specimen (11); A jacking device (4) is provided on one side of the reaction frame (1), the telescopic end of the jacking device (4) extends into the reaction frame (1) and contacts the layered rock specimen (11), and a high-speed camera (5) is provided on the other side of the reaction frame (1) relative to the jacking device (4).

2. The layered rock tunnel failure mode experimental device according to claim 1, characterized in that: A lifting bracket (6) is arranged below the jacking device (4).

3. An experimental method, characterized in that: The layered rock tunnel failure mode experimental device according to any one of claims 1 to 2 is used to conduct an experiment, comprising the following steps: S1. Making two or more partitions (7), and depicting the bedding surface characteristics on both sides of the partition (7) according to the JRC coefficient of the bedding surface of the on-site rock mass; S2. A layered rock specimen model box (8) with an open top is manufactured, and a tunnel model column (9) and two or more mutually parallel partitions (7) are vertically placed in the layered rock specimen model box (8). The number of the partitions (7) is N, and the partitions (7) divide the layered rock specimen model box (8) into N+1 chambers (10); S3, first pouring: select a number of chambers (10) at intervals, use gypsum slurry to pour the batch of chambers (10), and after the gypsum is initially set, remove all partitions (7) in the layered rock specimen model box (8); S4, burying a number of distributed optical fiber sensors on both sides of the gypsum board formed by the first pouring; S5, second pouring: using gypsum slurry to pour all the remaining chambers (10), after the gypsum is initially set, the tunnel model column (9) is removed; S6, third pouring: using gypsum slurry to pour the cavity after removing the tunnel model column (9), and obtaining a layered rock mass specimen (11) after solidification; S7, taking out the layered rock mass specimen (11) and placing it in the reaction frame (1), ensuring that the axis of the third pouring part is parallel to the ground, setting the preload pressure of the jacks (2) around it according to the stress conditions of the rock mass on site, restoring the stress conditions on site and fixing the layered rock mass specimen by the reaction steel plate (3); S8, arranging the jacking device (4) on one side of the layered rock mass specimen (11), adjusting the jacking position to the third pouring position, setting parameters such as the drilling speed, and ensuring that the jacking distance is greater than the thickness of the layered rock mass specimen (11); S9, placing the high-speed camera (5) on the other side of the layered rock mass specimen (11), and adjusting the angle and position of the high-speed camera (5) so that its photographic range completely covers the layered rock mass specimen (11); S10, connect several distributed optical fiber sensors to the data acquisition terminal, make preparations for debugging, and set parameters such as acquisition frequency; S11. Arrange a number of acoustic emission instruments at a corner of the layered rock specimen (11); S12, start the high-speed camera (5), the distributed optical fiber sensor and the acoustic emission instrument, load the surrounding jacks (2) to the target load, and start the jacking device (4) to push the third pouring part until the third pouring part is completely separated from the layered rock mass specimen (11). During the jacking process, check the collection status of each monitoring instrument at all times, and stop drilling and adjust the parameters in time when an abnormal situation occurs; S13. After the jacking is completed, the jacks (2) on all sides are used to apply pressure in stages for multiple times. After the target load is reached, the load is held for a period of time. After the information recording of all aspects is completed and there is no abnormality, the next stage of loading is continued. The holding time for each time is at least 5 minutes, and the loading is stopped until the layered rock mass specimen (11) shows obvious damage; S14. The images in the high-speed camera (5) are transmitted to the DIC device so that the experimenters can check the changing rules of the tunnel surrounding rock stress field during the tunnel drilling, loading and destruction processes. The displacement of the deep rock mass along the bedding structure surface is checked by transmitting data through the distributed optical fiber sensor. The number of surrounding rock cracks generated at different stages is analyzed by the acoustic emission instrument data, and the final experimental data is summarized.

4. An experimental method according to claim 3, characterized in that: Before executing step S7, white paint is sprayed on the surface of the layered rock mass specimen (11), and black scattered spots are evenly arranged on the surface of the layered rock mass specimen (11).

5. An experimental method according to claim 3, characterized in that: Before executing step S6, lubricant is applied in the cavity formed by removing the tunnel model column (9).

Images