Simulation test device and test method for mechanical behavior characteristics of cross-fault tunnels under different burial depths and different structural stresses

Abstract

The present invention discloses a simulation test device and a test method for the mechanical behavior characteristics of cross-fault tunnels and lanes under different burial depths and different tectonic stresses. The simulation test device includes a support frame, a loading hopper, a guide rail, a slider, a bidirectional power system and a confining pressure loading system. The design of the confining pressure loading system is provided to simulate the overburden pressure and horizontal tectonic stress for the surrounding rock materials in the fixed hopper and the movable hopper. At the same time, the bidirectional power system, the guide rail and the slider are used to enable the movable hopper to move in both horizontal and longitudinal directions, thereby achieving the simulation of complex engineering environments with different burial depths, different tectonic stresses, and fault complex dislocations, as well as the simulation of the mechanical behavior characteristics of tunnels and lanes under such environments. The present invention can more realistically restore the actual engineering situation, improve the accuracy of the research on the mechanical behavior characteristics of cross-fault tunnels and lanes under deep high ground stress conditions, and solve the problem that the existing physical model box cannot simulate the influence of overburden pressure and tectonic stress on tunnels and lanes.

Description

Technical Field

[0001] The invention belongs to the field of geotechnical engineering and tunnel engineering, and relates to a mechanical behavior characteristic simulation test device and a test method for a cross-fault tunnel under different burial depths and different structural stresses. Background Art

[0002] With the development of my country's economy, railways and urban rail transit have developed rapidly. In particular, railway rail transit, as the main artery of the national economy, important national infrastructure and popular transportation, plays an important role in the development of the national economy and society. Building a modern rail transit equipment industry innovation system and creating a full industrial chain layout covering trunk railways, intercity railways, urban (suburban) railways and urban rail transit is also one of the key points of the national strategic emerging industry development plan. Due to the mountainous geographical conditions in western my country, the construction of tunnels and lanes during railway construction occupies a large part of the engineering volume, and the geological conditions in the western mountainous areas are complex. It is often necessary to excavate under deep high ground stress (large burial depth, high tectonic stress). More and more difficult and complex tunnel and lane engineering have appeared. Therefore, the research and development of tunnel and lane engineering under complex geological conditions is of vital importance to the development of railway rail transit. In addition, according to incomplete statistics, in terms of coal mining, there are about 47 deep wells of coal mines exceeding one kilometer in China; in terms of underground caverns, taking Jinping underground caverns in my country as an example, the vertical burial depth has reached more than 2,400 meters. It can be seen that the development and utilization of underground resources in my country has also entered the deep field. When excavating under deep high-in-situ stress conditions, the deformation of the rock mass around the tunnels and lanes is generally large due to the existence of high overburden pressure and high tectonic stress, especially the rock mass with low strength and large deformation modulus, which is prone to tunnel collapse, tunnel roof collapse, bottom bulge and lateral expansion. In hard and brittle rock areas, it can also induce rock bursts and other disasters. However, people's understanding of the deformation and failure mechanism of tunnels and lanes under deep high-in-situ stress conditions is not clear enough, which greatly restricts the development of rail transit and the utilization of deep-earth resources.

[0003] In addition, tunnel construction will also encounter the situation of crossing unfavorable geological bodies such as faults or broken zones. The surrounding rock strength near faults and broken zones is often low, the cracks are significantly developed, and the water permeability is strong. During construction, it is very easy to have engineering accidents such as arch collapse, uneven settlement, and sudden water and mud, which will cause heavy losses to the construction. At the same time, tectonic fault zones are often seismic activity zones. Earthquakes and other geological tectonic movements can cause such fault activities, causing major damage to tunnels under construction or already built, causing serious loss of life and property. Therefore, in-depth research on the deformation and failure characteristics of tunnels in the complex environment of deep burial, high tectonic stress, and fault broken zones is of great significance for guiding tunnel engineering practice.

[0004] The main research methods for the mechanical behavior characteristics of tunnels and tunnels include on-site in-situ testing, numerical simulation, and physical model testing. The most effective method is on-site in-situ monitoring, that is, obtaining the most realistic and original monitoring data through stress, strain and displacement monitoring elements pre-buried in the tunnel lining or inner wall. Although this method can accurately reflect the actual situation on site, due to the limitation of site space, the monitoring cycle is long and the monitoring cost is high, and only local sections are often selected for monitoring, and the results are discontinuous. Numerical simulation is to use computers to model according to the geological condition parameters measured on site, so as to analyze the mechanical behavior characteristics of the structure. However, in order to facilitate computer modeling and calculation, the actual problems are often simplified during operation, so that the established model cannot truly reflect the on-site situation. The physical model test is to establish a model structure corresponding to the whole or part of the tunnel prototype structure according to a certain physical and geometric similarity relationship. The physical model can be used to observe and explore the entire process of the mechanical characteristics of the original structure. The physical model is generally small in geometric size, and relevant tests can be completed indoors. In addition, the cost of the physical model is moderate, the test is no longer restricted by the site, the operation is convenient, and the results are intuitive. Therefore, it occupies an important position in various engineering science research.

[0005] Regarding the physical model test of the mechanical behavior characteristics of the tunnel, the existing model box can often only simulate one disturbance factor in different confining pressures or across faults, and the simulation of the fault can mostly only achieve sliding in a single direction. CN109839315A discloses a bidirectional sliding physical model box for simulating a cross-fault tunnel and a test method for the mechanical behavior of a cross-fault tunnel. The physical model box includes a support frame, a loading hopper, a guide rail, a slider and a bidirectional power system. Through the cooperation of the guide rail, the slider and the bidirectional power system, although it can achieve the simulation of the composite dislocation, it does not consider the influence of the tectonic stress of the strata around the tunnel in the actual situation, especially the influence of the high overburden pressure and high tectonic stress on the tunnel under the deep high ground stress conditions. It is impossible to simulate the actual composite engineering environment of large burial depth, high tectonic stress and cross-fault fracture zone well, and there is still room for improvement in more realistic restoration of the actual engineering situation. Therefore, it is urgent to realize the simulation device and method of the mechanical behavior characteristics of cross-fault tunnels under various dislocation conditions, large burial depths and high tectonic stresses. Summary of the invention

[0006] In view of the shortcomings of the prior art, one of the purposes of the present invention is to provide a simulation test device for the mechanical behavior characteristics of cross-fault tunnels under different burial depths and different tectonic stresses, so as to solve the problem that the existing physical model box of the mechanical behavior characteristics of tunnels cannot simulate the actual engineering conditions of deep excavation and high ground stress, so as to realize the simulation of the complex engineering environment of fault complex dislocation under different burial depths and different tectonic stresses, and more realistically restore the actual engineering situation. The second purpose of the present invention is to provide a test method for the mechanical behavior characteristics of cross-fault tunnels under different burial depths and different tectonic stresses based on the test device provided by the present invention.

[0007] In order to achieve the above-mentioned invention object, the technical solution provided by the present invention is as follows:

[0008] The present invention provides a mechanical behavior characteristic simulation test device for a cross-fault tunnel under different burial depths and different tectonic stresses, comprising a support frame, a loading hopper, a guide rail, a slider, and a bidirectional power system. The support frame comprises a main frame, a first sub-frame, and a second sub-frame. The main frame is composed of an upper frame and a lower frame for supporting the upper frame. The upper frame is a rectangular parallelepiped frame with a hollow inner cavity. The support frame also comprises a third sub-frame and a confining pressure loading system.

[0009] The upper frame of the main frame is provided with a chamfered frame that runs through the front and rear side surfaces and the top and bottom surfaces. The chamfered frame is composed of two crossbeams that are perpendicular to and intersect with the top and bottom frame bars of the upper frame, and two oblique beams that intersect with the front and rear side frame bars of the upper frame at a certain angle. The chamfered frame divides the upper frame into a movable hopper accommodating portion and a fixed hopper mounting portion including the chamfered frame; the top of the front side surface of the upper frame corresponding to the movable hopper accommodating portion is set without a frame bar, forming a gap for the movable hopper to pass through when it moves horizontally; the first sub-frame is fixed On the rear side of the movable hopper accommodating portion, the second sub-frame is fixed to the front side of the fixed hopper mounting portion, and is a right-angled trapezoidal frame that matches the shape of the front side; the inclined surface frame of the second sub-frame is flush with the chamfered surface frame of the main frame, and together constitutes an extended chamfered surface frame; the third sub-frame is fixed to the top surface of the fixed hopper mounting portion, and is a rectangular parallelepiped frame that matches the shape of the top surface; the front side of the second sub-frame and the top surface of the third sub-frame are both provided with a confining pressure jack mounting crossbeam, and the rear side of the first sub-frame is provided with a displacement jack mounting inclined beam that is parallel to the inclined beam of the chamfered surface frame;

[0010] The loading hopper includes a fixed hopper and a movable hopper; the fixed hopper is composed of a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate installed on the corresponding surface of the fixed hopper mounting part of the upper frame, and the corresponding surface, top surface and front side surface of the chamfered surface frame of the fixed hopper mounting part remain open; the movable hopper is composed of a movable hopper frame, a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate, and the movable hopper frame is composed of a movable hopper frame main body with a hollow inner cavity that matches the shape of the movable hopper accommodating part of the upper frame in the main frame, as well as a side frame and a top frame; the movable hopper frame main body is an inverted right-angled trapezoidal body, the inclined surface frame of the movable hopper frame main body is parallel to the chamfered surface frame of the fixed hopper mounting part, and the side frame is fixed to the front side surface of the movable hopper frame main body, which is shaped similar to the front side surface. A matching inverted right-angle trapezoidal body frame, the inclined surface frame of the side frame is flush with the inclined surface frame of the movable hopper frame body, forming an extended inclined surface frame, the extended inclined surface frame is the same size as the extended chamfered surface frame formed by the fixed hopper mounting portion and the second sub-frame in the support frame and is parallel to each other, the top frame is fixed to the top surface of the movable hopper frame body, and is a rectangular parallelepiped frame matching the shape of the top surface; the bottom plate and side plates of the movable hopper are correspondingly mounted on the bottom and side surfaces of the movable hopper frame body, and the front side surface, inclined surface and top surface of the movable hopper frame body are open; a displacement jack mounting beam is provided on the rear side surface of the movable hopper frame body, and a confining pressure jack mounting beam is provided on the top surface of the top frame and the front side surface of the side frame; a lining model placement port is provided on the rectangular side panels of the fixed hopper and the movable hopper;

[0011] The bidirectional power system includes a displacement jack that provides power for horizontal and longitudinal movement of the movable hopper;

[0012] The guide rails include a movable hopper guide rail, an oblique displacement jack guide rail and a horizontal displacement jack guide rail; the movable hopper guide rails include two mutually parallel oblique movable hopper guide rails and two mutually parallel horizontal movable hopper guide rails; the oblique movable hopper guide rails are respectively installed on two oblique beams of the extended beveled surface frame formed by the main frame and the second sub-frame, and a slider is installed on the oblique movable hopper guide rail. The horizontal movable hopper guide rail is installed on the slider of the oblique movable hopper guide rail and is perpendicular to the oblique movable hopper guide rail. A slider is installed on the guide rail, and the slider of the horizontal movable hopper guide rail is fixed on the extended inclined surface frame of the movable hopper frame; the oblique displacement jack guide rail is installed on the displacement jack installation inclined beam of the first sub-frame, and a slider is installed on the oblique displacement jack guide rail, and the oblique displacement jack guide rail and the oblique movable hopper guide rail are parallel to each other; the horizontal displacement jack guide rail is installed on the lower frame below the movable hopper accommodating part, and the horizontal displacement jack guide rail and the horizontal movable hopper guide rail are parallel to each other, and a slider is installed on the horizontal jack guide rail;

[0013] The displacement jack includes a horizontally arranged displacement jack and a displacement jack arranged perpendicular to the horizontal plane; the bottom of the horizontally arranged displacement jack is installed on the oblique displacement jack guide rail through a slider, and the top is fixed on the displacement jack installation beam of the movable hopper frame body; the bottom of the displacement jack arranged perpendicular to the horizontal plane is installed on the horizontal displacement jack guide rail through a slider, and the top is in contact with the bottom plate of the movable hopper through a supporting pad;

[0014] The confining pressure loading system includes confining pressure jacks for providing simulated overburden pressure and horizontal tectonic stress for surrounding rock materials in the fixed hopper and the movable hopper; the bottoms of the confining pressure jacks are respectively mounted on the confining pressure jack mounting cross beams of the second sub-frame, the third sub-frame, the side frame of the movable hopper frame, and the top frame of the movable hopper frame, and the tops of the confining pressure jacks are respectively mounted with pressure plates for applying confining pressure to the surrounding rock materials in the loading hopper;

[0015] Both displacement jacks and confining pressure jacks are used in conjunction with oil pumps, oil pipelines and power distribution control boxes.

[0016] In the technical solution of the above-mentioned simulation test device, the angle α between the chamfered surface frame on the upper frame and the bottom plate of the fixed hopper is 30° to 80°.

[0017] In the technical solution of the above-mentioned simulation test device, there are at least 4 confining pressure jacks, and a pad is provided between the pressure plate and the top of the confining pressure jack, and the pressure plate is fixedly connected to the top of the confining pressure jack through the pad and screws. The size of the pressure plate does not exceed the size of the corresponding surface of the movable hopper and the fixed hopper at the installation position of the pressure plate. Preferably, the shape of the pressure plate is the same as the shape of the corresponding surface of the movable hopper and the fixed hopper at the installation position of the pressure plate. When the bottom of the confining pressure jack is installed on the confining pressure jack installation beam of the second sub-frame and the side frame of the movable hopper frame, the confining pressure jack is installed horizontally, and the pressure plate connected to the confining pressure jack is arranged perpendicular to the horizontal plane and parallel to the front side of the upper frame; when the bottom of the confining pressure jack is installed on the confining pressure jack installation beam of the third sub-frame and the top frame of the movable hopper frame, the confining pressure jack is installed perpendicular to the horizontal plane, and the pressure plate connected to the confining pressure jack is arranged horizontally and parallel to the bottom plate of the upper frame.

[0018] In the technical scheme of the above-mentioned simulation test device, the distance between the two inclined movable hopper guide rails is 1.5 to 2 times the distance between the front and rear side surfaces of the upper frame, and the length of the inclined movable hopper guide rail is greater than or equal to the length of the inclined beam of the beveled surface frame on the upper frame; the distance between the two horizontal movable hopper guide rails is 0.6 to 0.8 times the length of the inclined beam of the beveled surface frame on the upper frame, and the slider of one of the horizontal movable hopper guide rails is fixed on the bottom frame bar of the inclined surface frame of the movable hopper frame body.

[0019] In the technical solution of the above-mentioned simulation test device, the gap between the inclined beam of the chamfered surface frame of the upper frame and the movable hopper is sealed by a rubber strip to prevent the surrounding rock material from leaking out when the surrounding rock material is laid into the loading hopper.

[0020] In the technical solution of the above-mentioned simulation test device, the number of the oblique displacement jack guide rails and the horizontal displacement jack guide rails, as well as the number of each displacement jack are determined according to the size of the above-mentioned loading hopper, especially the size of the movable hopper, with the basic principle of being able to provide sufficient power for the longitudinal movement of the movable hopper. There are 1 to 3 oblique displacement jack guide rails, each of which is parallel to each other, and each oblique displacement jack guide rail is provided with a displacement jack; there are 1 to 3 horizontal displacement jack guide rails, each of which is parallel to each other, and each of which is provided with 1 to 2 displacement jacks.

[0021] In the technical solution of the above-mentioned simulation test device, both the confining pressure jack and the displacement jack are hydraulic jacks.

[0022] In the technical scheme of the above-mentioned simulation test device, in order to facilitate the installation and fixation of the bottom plates and side plates of the fixed hopper on the fixed hopper mounting part of the upper frame, and the installation and fixation of the bottom plates and side plates of the movable hopper on the movable hopper frame, the support frame and the movable hopper frame are preferably welded from angle steels; in order to facilitate the observation of the condition of the surrounding rock material in the loading hopper while ensuring the strength of the loading hopper, the side plates of the fixed hopper and the movable hopper are preferably made of tempered glass, and the bottom plates of the fixed hopper and the movable hopper, and the pressure plates of the confining pressure jacks are made of steel plates.

[0023] In the technical solution of the above-mentioned simulation test device, the shape of the lining model inlet provided on the rectangular side panels of the fixed hopper and the movable hopper is determined according to the shape of the lining model, and the setting position of the lining model inlet is determined according to the installation position of the lining model. For example, the lining model can be a circular opening to simulate a circular tunnel. The lining model inlets on the rectangular side panels of the fixed hopper and the movable hopper are set at the same position of the rectangular side panels, so that the lining model inlets can be passed through by the lining model with the same axis parallel to the upper frame crossbeam.

[0024] In the technical solution of the above-mentioned simulation test device, in order to more conveniently obtain the filling thickness information of the surrounding rock material when using the device, the preferred technical solution is: setting scale lines on the side panels of the fixed hopper and the movable hopper.

[0025] In the technical solution of the above-mentioned simulation test device, in order to facilitate the movement of the device, universal wheels are provided at the bottom of the lower frame.

[0026] In the technical solution of the above-mentioned simulation test device, in order to make the movement of the movable hopper more convenient and flexible, it is preferred that the volume of the fixed hopper is larger than the volume of the movable hopper.

[0027] In the technical solution of the above-mentioned simulation test device, in order to realize the horizontal and longitudinal movement of the movable hopper on the main frame, the overall size of the movable hopper should be slightly smaller than the size of the movable hopper accommodating portion of the upper frame.

[0028] In the technical solution of the above-mentioned simulation test device, the oblique displacement jack guide rail, horizontal displacement jack guide rail, oblique movable hopper guide rail and horizontal movable hopper guide rail preferably adopt linear optical axis guide rails, and the sliders matched with each guide rail preferably adopt open linear bearings.

[0029] Since the above-mentioned simulation test device provided by the present invention is mainly used to simulate the destruction process of cross-fault tunnels under different burial depths and different structural stresses indoors, the specific dimensions of the simulation test device as a whole, the proportional relationship between the volumes of the fixed hopper and the movable hopper, the size of the angle α between the chamfered surface frame on the upper frame and the bottom plate of the fixed hopper, the setting position and dimensions of the lining model placement port and other parameters can be determined based on the original structure and the proportional relationship between the simulation test device and the original structure.

[0030] The present invention also provides a method for testing the mechanical behavior characteristics of a cross-fault tunnel under different burial depths and different tectonic stresses using the simulation test device of the present invention, comprising the following steps:

[0031] ① Brush a layer of engine oil on the inner wall of the loading hopper of the simulation test device, adjust the position of the movable hopper of the simulation test device according to the test requirements, install a displacement meter on the simulation test device, lay surrounding rock materials into the loading hopper in the simulation test device, and install lining models, strain gauges and earth pressure cells in the surrounding rock materials during the laying of surrounding rock materials;

[0032] Before laying the surrounding rock materials, adjust the positions of the pressure plates, especially the pressure plates arranged perpendicular to the horizontal plane, so that the pressure plates arranged perpendicular to the horizontal plane are in contact with the bottom plates of the movable hopper and the fixed hopper to prevent the surrounding rock materials that have not yet solidified from leaking;

[0033] ② After the surrounding rock material is laid to the required height for the test, it is left to stand until the surrounding rock material reaches the required strength for the test. According to the test needs, the oil pump is turned on to control the confining pressure jack to apply vertical and horizontal pressure to the surrounding rock material to simulate the overlying stratum pressure and tectonic stress respectively; by adjusting the magnitude of the vertical and horizontal pressure applied by the confining pressure jack to the surrounding rock material, different burial depths and different tectonic stress conditions are simulated;

[0034] ③ According to the test needs, the oil pump is turned on to control the displacement jack to provide power for the horizontal and / or longitudinal movement of the movable bucket. The monitoring instrument connected with the strain gauge and the earth pressure box is used to monitor the stress and strain data of the movable bucket when it moves horizontally and / or longitudinally under different burial depths and different structural stresses in real time. At the same time, the displacement meter is used to measure the horizontal and longitudinal movement distance of the movable bucket in real time;

[0035] ④ By analyzing the stress, strain and displacement data collected in step ③, the mechanical behavior characteristics of the tunnel under different overlying formation pressures and different tectonic stress conditions, such as strike-slip faults, normal-reverse faults or composite dislocations, are obtained.

[0036] In the technical solution of the above-mentioned cross-fault tunnel mechanical behavior test method, in step ①, when laying the surrounding rock material into the loading hopper of the simulation test device, it is best to adopt a layered laying method, and lay the next layer after laying and compacting one layer to ensure the density of the surrounding rock material after laying. In order to ensure that the movement of the active hopper is not affected by the surrounding rock material laid in the loading hopper, the laying thickness of the surrounding rock material in the loading hopper should not exceed the installation position height of the horizontal active hopper guide rail at the top.

[0037] In the above test method, the purpose of step ① of brushing a layer of engine oil on the inner wall of the loading hopper of the simulation test device before laying the surrounding rock material is: on the one hand, to reduce the influence of the boundary effect of the physical model box on the simulation results and more realistically restore the on-site conditions of engineering practice; on the other hand, to facilitate the removal of the test materials in the loading hopper after the test is completed.

[0038] In the above test method, in order to realize the monitoring and quantitative control of the horizontal movement distance and the longitudinal movement distance of the movable hopper, two displacement meters need to be installed on the simulation test device in step ①, which are respectively used to measure the horizontal movement distance and the longitudinal movement distance of the movable hopper. The displacement meter preferably used is a digital displacement dial indicator, and is used in conjunction with a universal magnetic base. The digital displacement dial indicator is fixed on the universal magnetic base, and the universal magnetic base is fixed on the upper frame near the open side of the fixed hopper and the movable hopper.

[0039] In the above test method, step ① can also embed monitoring elements such as strain bricks in the tunnel lining model and surrounding rock materials according to test requirements.

[0040] In the above test method, step ① usually involves adjusting the position of the movable hopper before laying the surrounding rock material so that the chamfered surface frame of the open fixed hopper and the inclined surface frame of the movable hopper cooperate with each other to form a loading hopper with a rectangular trough structure. If the test needs to simulate the impact of normal fault movement on a cross-fault tunnel, the movable hopper should be raised to a predetermined research height before laying the surrounding rock material.

[0041] In the above test method, after the test is completed, the surrounding rock materials, lining models and other test materials in the loading hopper should be removed and properly disposed of as construction waste, and the loading hopper should be cleaned for use in the next test.

[0042] In the above test method, the mechanical behavior data of the cross-fault tunnel include stress-strain data of the physical model, stress-strain data of the surrounding rock material, etc.

[0043] Compared with the prior art, the technical solution provided by the present invention produces the following beneficial technical effects:

[0044] 1. The present invention provides a simulation test device for the mechanical behavior characteristics of cross-fault tunnels and lanes under different burial depths and different tectonic stresses, which includes a support frame, a loading hopper, a guide rail, a slider, a bidirectional power system and a confining pressure loading system. The confining pressure loading system is designed to provide a simulated overburden pressure and horizontal tectonic stress for the surrounding rock materials in the fixed hopper and the movable hopper. At the same time, the bidirectional power system, the guide rail and the slider enable the movable hopper to move in both horizontal and longitudinal directions. The simulation of complex engineering environments with different burial depths, different tectonic stresses and fault complex dislocations, as well as the simulation of the mechanical behavior characteristics of tunnels and lanes under such environments, is realized. In particular, the simulation of the mechanical behavior characteristics of tunnels and lanes under high overburden pressure and high tectonic stress conditions is realized, which more realistically restores the actual engineering situation, improves the accuracy of the study on the mechanical behavior characteristics of cross-fault tunnels and lanes under deep high ground stress conditions, and solves the problem that the existing physical model box cannot simulate the influence of overburden pressure and tectonic stress on tunnels and lanes.

[0045] 2. Since the simulation test device described in the present invention can simulate the mechanical behavior characteristics of cross-fault tunnels under a variety of complex conditions, the device has high utilization efficiency and strong adaptability, thereby reducing the overall cost of studying the mechanical behavior characteristics of cross-fault tunnels.

[0046] 3. Based on the above-mentioned simulation test device, the present invention also provides a method for testing the mechanical behavior characteristics of cross-fault tunnels under different burial depths and different tectonic stresses. The method can test the mechanical behavior of cross-fault tunnels under different burial depths and different tectonic stresses under strike-slip faults, normal-reverse faults and composite dislocation conditions. Since composite dislocation conditions and tectonic stress conditions are closer to the actual engineering situation, the measured mechanical behavior data of cross-fault tunnels are more accurate, especially the mechanical behavior characteristic data of tunnels excavated under deep high ground stress conditions can be obtained, which improves the accuracy of the research on the mechanical behavior characteristics of cross-fault tunnels and is conducive to guiding actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a front view of the simulation test device provided by the present invention;

[0048] Figure 2 is a rear view of the simulation test device provided by the present invention;

[0049] Figure 3 It is a right side view of the simulation test device provided by the present invention;

[0050] Figure 4 It is a schematic diagram of the installation of the movable hopper guide rail of the simulation test device provided by the present invention on the bevel frame of the main frame;

[0051] Figure 5 It is a schematic diagram of the supporting frame structure of the simulation test device provided by the present invention;

[0052] Figure 6 It is a schematic diagram of the movable hopper frame structure of the simulation test device provided by the present invention;

[0053] In the figure, 1-support frame, 1-1-main frame, 1-1-1-fixed hopper installation part, 1-1-2-movable hopper accommodating part, 1-2-first sub-frame, 1-3-second sub-frame, 1-4-third sub-frame, 1-5-confining pressure jack installation crossbeam, 1-6-displacement jack installation inclined beam, 2-bevel frame, 3-fixed hopper, 4-movable hopper, 4-1-movable hopper frame body, 4-2-side frame, 4-3-top frame, 4-4-displacement jack installation Crossbeam, 5—lining model placement entrance, 6—displacement jack, 7—confining pressure jack, 7-1—pressure plate, 7-2—shim plate, 7-3—screw, 8—oil pump, 9—oil pipeline, 10—power distribution control box, 11—oblique displacement jack guide rail, 12—horizontal displacement jack guide rail, 13—oblique movable hopper guide rail, 14—horizontal movable hopper guide rail, 15—slider, 16—rubber strip, 17—universal wheel, α—the angle between the oblique beam on the upper frame and the bottom plate of the fixed hopper. DETAILED DESCRIPTION

[0054] The following is a further description of the mechanical behavior characteristics simulation test device of the cross-fault tunnel under different burial depths and different tectonic stresses provided by the present invention and the mechanical behavior characteristics test method of the cross-fault tunnel under different burial depths and different tectonic stresses. It is necessary to point out that the following implementation method is only used to further illustrate the operation and use of the present invention, and cannot be understood as limiting the protection scope of the present invention. It is very easy for a person familiar with the technology in the relevant field to make some non-essential improvements and adjustments to the present invention based on the above invention content. Therefore, such improvements and adjustments should still fall within the protection scope of the present invention.

[0055] In the following embodiments, the directional words such as "front" and "rear" are relative directional references used to more clearly describe the structure and have no limiting effect on the specific structure of the simulation test device.

[0056] In the following embodiments, the oblique displacement jack guide, the horizontal displacement jack guide, the oblique movable hopper guide and the horizontal movable hopper guide use linear optical axis guides of model SBR3UU, and the sliders matched with each guide use open linear bearings of model LM30UU-OP.

[0057] Example 1

[0058] The mechanical behavior characteristics simulation test device of the cross-fault tunnel under different burial depths and different tectonic stresses described in this embodiment has a structure as follows: Figure 1-Figure 6 As shown, it includes a supporting frame 1, a loading hopper, guide rails, a slider, a bidirectional power system and a confining pressure loading system.

[0059] The support frame 1 is composed of a main frame 1-1, a first sub-frame 1-2, a second sub-frame 1-3 and a third sub-frame 1-4. The main frame 1-1 is composed of an upper frame and a lower frame for supporting the upper frame. The upper frame is a rectangular parallelepiped frame with a hollow inner cavity. The upper frame is provided with a beveled frame 2 that runs through the front and rear side surfaces and the top and bottom surfaces. The beveled frame 2 is composed of two crossbeams that are perpendicular to and intersect with the top and bottom frame bars of the upper frame, and two oblique beams that intersect with the front side frame bars and the rear side frame bars of the upper frame. The beveled frame 2 divides the upper frame 1-1 into a movable hopper accommodating portion 1-1-2 and a fixed hopper mounting portion 1-1-1 including the beveled frame. The angle α between the beveled frame and the bottom surface of the upper frame is 60°. The top of the front side surface of the upper frame 1-1 corresponding to the movable hopper accommodating portion 1-1-2 is set without a frame bar, forming a gap for the movable hopper 4 to pass through when it moves horizontally. The first sub-frame 1-2 is fixed to the rear side of the movable hopper accommodating part 1-1-2, and is a rectangular parallelepiped frame that completely covers the rear side; the second sub-frame 1-3 is fixed to the front side of the fixed hopper mounting part 1-1-1, and is a right-angled trapezoidal frame that matches the shape of the front side; the inclined surface frame of the second sub-frame 1-3 is flush with the chamfered surface frame 2 of the main frame, and together they form an extended chamfered surface frame; the third sub-frame 1-4 is fixed to the top surface of the fixed hopper mounting part 1-1-1, and is a rectangular parallelepiped frame that matches the shape of the top surface. The front side of the second sub-frame 1-3 and the top surface of the third sub-frame 1-4 are both provided with a confining pressure jack mounting crossbeam 1-5; the rear side of the first sub-frame 1-2 is provided with a displacement jack mounting inclined beam 1-6 that is parallel to the inclined beam of the chamfered surface frame 2. The support frame is welded from angle steel. The bottom of the lower frame of the main frame of the support frame is provided with a universal wheel 17 for easy movement.

[0060] The loading hopper includes a fixed hopper 3 and a movable hopper 4. In order to make the movement of the movable hopper more convenient and flexible, the volume of the fixed hopper 3 is larger than that of the movable hopper 4. The fixed hopper 3 is composed of a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate installed on the corresponding surface of the fixed hopper mounting part of the upper frame. The corresponding surface, top surface and front side surface of the chamfered surface frame of the fixed hopper mounting part 1-1-1 remain open. The movable hopper 4 is composed of a movable hopper frame, a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate. The movable hopper frame is composed of a movable hopper frame body 4-1 with a hollow inner cavity that matches the shape of the movable hopper accommodating part 1-1-2 of the upper frame in the main frame, as well as a side frame 4-2 and a top frame 4-3. In order to realize the horizontal and longitudinal movement of the movable hopper on the main frame, the overall size of the movable hopper should be slightly smaller than the size of the movable hopper accommodating part of the upper frame. The movable hopper frame body 4-1 is an inverted right-angled trapezoid, the inclined surface frame of the movable hopper frame body and the beveled surface frame of the fixed hopper mounting portion 1-1-1 are parallel to each other and placed opposite to each other, the side frame 4-2 is fixed to the front side of the movable hopper frame body 4-1, and is an inverted right-angled trapezoidal body frame matching the shape of the front side, the inclined surface frame of the side frame is flush with the inclined surface frame of the movable hopper frame body, forming an extended inclined surface frame, and the extended inclined surface frame is connected to the extended beveled surface formed by the fixed hopper mounting portion 1-1-1 and the second sub-frame 1-3 in the support frame. The frames are of the same size and parallel to each other. The top frame 4-3 is fixed on the top surface of the movable hopper frame body 4-1, and is a rectangular parallelepiped frame that matches the shape of the top surface. The bottom plate and side plates of the movable hopper are correspondingly installed on the bottom and side surfaces of the movable hopper frame body. The front side surface, inclined surface and top surface of the movable hopper frame body are open. The rear side surface of the movable hopper frame body 4-1 (the side surface where the right-angle trapezoidal side plate is installed) is provided with a displacement jack mounting crossbeam 4-4, and the top surface of the top frame 4-3 and the front side surface of the side frame 4-2 are provided with a confining pressure jack mounting crossbeam 1-5. A circular lining model entry 5 is provided at the same position on the rectangular side plates of the fixed hopper and the movable hopper, so that the lining model entry can be passed through by a circular pipe with the same axis parallel to the upper frame crossbeam to simulate a tunnel. The gap between the inclined beam of the chamfered frame of the upper frame and the movable hopper 4 is blocked by a rubber strip 16 to prevent leakage of surrounding rock materials. The movable hopper frame and the jack mounting crossbeam set thereon are welded into an integrated structure by angle steel. The side panels of the fixed hopper 3 and the movable hopper 4 are made of tempered glass, and the bottom panels of the fixed hopper 3 and the movable hopper 4 are made of steel plates, so as to facilitate observation of the surrounding rock material in the loading hopper while ensuring the strength of the loading hopper. Graduation lines are set on the side panels of the fixed hopper and the movable hopper to facilitate quick acquisition of the filling thickness of the surrounding rock material during the test.

[0061] The bidirectional power system includes a displacement jack 6 that provides power for the horizontal and longitudinal movement of the movable hopper, and the displacement jack is a hydraulic jack.

[0062] The guide rails include a movable hopper guide rail, an oblique displacement jack guide rail 11 and two horizontal displacement jack guide rails 12; the movable hopper guide rails include two mutually parallel oblique movable hopper guide rails 13 and two mutually parallel horizontal movable hopper guide rails 14. The two oblique movable hopper guide rails 13 are respectively mounted on two oblique beams of the extended bevel frame formed by the main frame and the second sub-frame, and the distance between the two oblique movable hopper guide rails 13 is 1.5 times the distance between the front and rear sides of the upper frame, and the length of the oblique movable hopper guide rails is equal to the length of the oblique beam of the bevel frame on the upper frame; each oblique movable hopper guide rail 13 is mounted with two sliding blocks 15, and the two ends of each horizontal movable hopper guide rail 14 are respectively connected to a sliding block on the two oblique movable hopper guide rails 13. The blocks are fixed on the sliders accordingly and are perpendicular to the inclined movable hopper guide rails 13. The distance between the two horizontal movable hopper guide rails 14 is 0.8 times the length of the inclined beam of the beveled surface frame on the upper frame; two sliders 15 are installed on each horizontal active hopper guide rail, one of which is fixed on the bottom frame bar of the inclined surface frame of the movable hopper frame body, and the two sliders 15 of the other horizontal movable hopper guide rail are respectively fixed on the inclined beams of the inclined surface frame of the movable hopper frame body. The oblique displacement jack guide rail 11 is installed on the displacement jack installation oblique beam 1-6 of the first sub-frame 1-2, and a slider 15 is installed on the oblique displacement jack guide rail 11. The oblique displacement jack guide rail and the oblique movable hopper guide rail 13 are parallel to each other; there are two horizontal displacement jack guide rails 12, which are installed on the lower frame below the movable hopper accommodating part 1-1-2. The horizontal displacement jack guide rail 12 and the horizontal movable hopper guide rail 14 are parallel to each other, and a slider 15 is installed on each horizontal displacement jack guide rail 12. The slider 15 is an open type linear bearing.

[0063] The displacement jack 6 includes a horizontal displacement jack and two displacement jacks arranged perpendicular to the horizontal plane. The bottom of the horizontal displacement jack is installed on the oblique displacement jack guide rail 11 through a slider 15, and the top is fixed on the displacement jack installation beam 4-4 of the movable hopper frame body 4-1. The bottom of the displacement jack arranged perpendicular to the horizontal plane is respectively installed on two horizontal displacement jack guide rails 12 through a slider 15, and the top is in contact with the bottom plate of the movable hopper through a support pad.

[0064] The confining pressure loading system is composed of four confining pressure jacks 7 for providing simulated overburden pressure and horizontal structural stress for the surrounding rock materials in the fixed hopper 3 and the movable hopper 4. The confining pressure jacks are hydraulic jacks. The bottoms of the four confining pressure jacks 7 are respectively mounted on the corresponding confining pressure jack mounting crossbeams 1-5 on the second sub-frame 1-3, the third sub-frame 1-4, the side frame 4-2 of the movable hopper frame, and the top frame 4-3 of the movable hopper frame; the tops of the confining pressure jacks 7 are respectively installed with pressure plates 7-1 for applying confining pressure to the surrounding rock materials in the loading hopper, and the pressure plates are made of steel plates. A pad 7-2 is provided between the pressure plate and the top of the confining pressure jack 7, and the pressure plate is fixed to the top of the confining pressure jack by screws 7-3 passing through the pressure plate and the pad. The size of the pressure plate does not exceed the size of the corresponding surface of the movable hopper and the fixed hopper at the installation position of the pressure plate. The shape of the pressure plate is the same as the shape of the corresponding surface of the movable hopper and the fixed hopper at the installation position of the pressure plate. Two of the four confining pressure jacks 7 are installed horizontally to simulate tectonic stress, and the other two are installed perpendicular to the horizontal plane to simulate vertical overlying stratum pressure. When the bottom of the confining pressure jack 7 is installed on the confining pressure jack installation beam 1-5 of the side frame of the second sub-frame and the movable hopper frame, the confining pressure jack 7 is installed horizontally, and the pressure plate connected to the confining pressure jack 7 is set perpendicular to the horizontal plane and parallel to the front side of the upper frame; when the bottom of the confining pressure jack 7 is installed on the confining pressure jack installation beam 1-5 of the top frame of the third sub-frame and the movable hopper frame, the confining pressure jack 7 is installed perpendicular to the horizontal plane, and the pressure plate connected to the confining pressure jack 7 is set horizontally and parallel to the bottom plate of the upper frame.

[0065] The displacement jack 6 and the confining pressure jack 7 are used in conjunction with an oil pump 8, an oil pipeline 9 and a power distribution control box 10.

[0066] Example 2

[0067] The simulation test device described in Example 1 is used to test the mechanical behavior characteristics of a tunnel under great burial depth, high tectonic stress, and complex dislocation, and the steps are as follows:

[0068] ① Brush a layer of engine oil on the inner wall of the loading hopper of the simulation test device to reduce the influence of the boundary effect of the physical model on the simulation results. Adjust the position of the movable hopper so that the extended beveled surface frame of the open fixed hopper and the inclined surface frame of the movable hopper cooperate with each other to form a loading hopper with a rectangular trough structure. Install two displacement meters on the movable hopper, which are used to measure the horizontal movement distance and longitudinal movement distance of the movable hopper respectively. The displacement meter used is a digital displacement dial indicator, which is used in conjunction with a universal magnetic base. The digital displacement dial indicator is fixed on the universal magnetic base, and the universal magnetic base is fixed on the upper frame near the connection section (open side) of the fixed hopper and the movable hopper. Before laying the surrounding rock material, adjust the position of each pressure plate, especially the pressure plate set perpendicular to the horizontal plane, so that the pressure plate set perpendicular to the horizontal plane contacts the bottom plate of the movable hopper and the fixed hopper to avoid leakage of the surrounding rock material that has not yet solidified.

[0069] The surrounding rock material is laid in the loading hopper in a layered manner. After each layer is laid and compacted, the next layer is laid to ensure the density of the surrounding rock material after laying. In order to ensure that the movement of the movable hopper is not affected by the surrounding rock material laid in the loading hopper, the laying thickness of the surrounding rock material in the loading hopper should not exceed the installation height of the horizontal movable hopper guide rail at the top. In the process of laying the surrounding rock material, the lining model cylindrical pipe that passes through the fixed hopper and the movable hopper is installed through the lining model entry set on the movable hopper and the fixed hopper to simulate the tunnel. At the same time, the lining model, strain gauge and earth pressure box are installed in the surrounding rock material. After installation, the surrounding rock material continues to be added and compacted until the height required for the test. Connect the relevant monitoring instruments corresponding to the monitoring components, and check whether the readings of the monitoring components such as displacement meters, strain gauges, and earth pressure boxes are normal. If normal, proceed to the next step, otherwise, timely repair and troubleshoot.

[0070] ② After the surrounding rock material is laid to the height required for the test, it is left to stand until the surrounding rock material reaches the strength required for the test. According to the test needs, the oil pump is turned on to control the confining pressure jack to apply vertical and horizontal pressure to the surrounding rock material to simulate the overlying stratum pressure and tectonic stress respectively; by adjusting the magnitude of the vertical and horizontal pressure applied to the surrounding rock material by the confining pressure jack, different burial depths and different tectonic stress conditions are simulated; before applying horizontal pressure, a certain vertical pressure should be pre-applied.

[0071] ③ According to the test needs, turn on the oil pump to control the displacement jack to provide power for the horizontal and longitudinal movement of the movable bucket, so that the movable bucket moves horizontally toward the front side of the upper frame while moving upward. The monitoring instrument connected to the strain gauge and the earth pressure box is used to monitor the stress and strain data of the movable bucket during horizontal and longitudinal movement in real time. At the same time, the displacement meter is used to measure the horizontal and longitudinal movement distance of the movable bucket in real time.

[0072] ④ Adjust the vertical and horizontal pressures applied by the confining pressure jack to the surrounding rock material, simulate different burial depths and different structural stress conditions, repeat the above steps, and collect the corresponding stress, strain and displacement data. By analyzing the stress, strain and displacement data collected in step ③, the mechanical behavior characteristics of the tunnel under the condition of composite dislocation are obtained.

[0073] ⑤ After the test, remove the surrounding rock materials, lining models and other test materials from the loading hopper, properly dispose of them as construction waste, and clean the loading hopper for the next test.

Claims

1. A device for simulating and testing the mechanical behavior characteristics of a cross-fault tunnel under different burial depths and different tectonic stresses, comprising a support frame (1), a loading hopper, a guide rail, a slider, and a bidirectional power system, wherein the support frame (1) comprises a main frame (1-1), a first sub-frame (1-2), and a second sub-frame (1-3), wherein the main frame (1-1) is composed of an upper frame and a lower frame for supporting the upper frame, wherein the upper frame is a rectangular parallelepiped frame with a hollow inner cavity, and wherein the device is characterized in that: Also includes a third subframe (1-4) and a confining pressure loading system; The upper frame of the main frame (1-1) is provided with a chamfered frame (2) penetrating the front and rear side surfaces and the top and bottom surfaces. The chamfered frame (2) is composed of two cross beams that are respectively perpendicular to and intersect with the top and bottom frame bars of the upper frame, and two oblique beams that respectively intersect with the front and rear side frame bars of the upper frame at a certain angle. The chamfered frame (2) divides the upper frame into a movable hopper accommodating portion (1-1-2) and a fixed hopper mounting portion (1-1-1) including the chamfered frame. The top of the front side surface of the upper frame corresponding to the movable hopper accommodating portion (1-1-2) is provided without a frame bar, so as to form a gap for the movable hopper (4) to pass through when moving horizontally. The first sub-frame (1-2) is fixed to the movable hopper accommodating portion (1-1 -2), the second sub-frame (1-3) is fixed to the front side of the fixed hopper mounting portion (1-1-1), and is a right-angled trapezoidal frame matching the shape of the front side; the inclined surface frame of the second sub-frame (1-3) is flush with the chamfered surface frame (2) of the main frame, and together constitutes an extended chamfered surface frame; the third sub-frame (1-4) is fixed to the top surface of the fixed hopper mounting portion (1-1-1), and is a rectangular parallelepiped frame matching the shape of the top surface; the front side of the second sub-frame (1-3) and the top surface of the third sub-frame (1-4) are both provided with a confining pressure jack mounting crossbeam (1-5), and the rear side of the first sub-frame (1-2) is provided with a displacement jack mounting inclined beam (1-6) parallel to the inclined beam of the chamfered surface frame (2); The loading hopper comprises a fixed hopper (3) and a movable hopper (4); the fixed hopper (3) is composed of a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate installed on the corresponding surface of the fixed hopper installation part of the upper frame, and the corresponding surface, top surface and front side surface of the chamfered surface frame of the fixed hopper installation part (1-1-1) remain open; the movable hopper (4) is composed of a movable hopper frame, a rectangular bottom plate, a rectangular side plate and a right-angled trapezoidal side plate, and the movable hopper frame is composed of a hollow inner cavity and a The main frame is composed of a movable hopper frame body (4-1) whose shape matches that of a movable hopper accommodating portion (1-1-2) of an upper frame in the main frame, a side frame (4-2) and a top frame (4-3); the movable hopper frame body (4-1) is an inverted right-angled trapezoid, the inclined surface frame of the movable hopper frame body and the beveled surface frame of the fixed hopper mounting portion (1-1-1) are parallel to each other, and the side frame (4-2) is fixed to the front side surface of the movable hopper frame body (4-1) and is an inverted right-angled trapezoid that matches the shape of the front side surface. The right-angled trapezoidal frame, the inclined surface frame of the side frame is flush with the inclined surface frame of the movable hopper frame body, forming an extended inclined surface frame, the extended inclined surface frame and the extended chamfered surface frame formed by the fixed hopper mounting portion (1-1-1) and the second sub-frame (1-3) in the support frame are of the same size and parallel to each other, the top frame (4-3) is fixed on the top surface of the movable hopper frame body (4-1), and is a rectangular parallelepiped frame matching the shape of the top surface; the bottom plate and side plates of the movable hopper are arranged correspondingly in shape. The movable hopper frame body is installed on the bottom and side surfaces, and the front side surface, inclined surface and top surface of the movable hopper frame body are open; a displacement jack mounting crossbeam (4-4) is provided on the rear side surface of the movable hopper frame body (4-1), and a confining pressure jack mounting crossbeam (1-5) is provided on the top surface of the top frame (4-3) and the front side surface of the side frame (4-2); a lining model insertion port (5) is provided on the rectangular side panels of the fixed hopper and the movable hopper; and scale lines are provided on the side panels of the fixed hopper and the movable hopper; The bidirectional power system includes a displacement jack (6) for providing power for the horizontal and longitudinal movement of the movable hopper; The guide rails include a movable hopper guide rail, an oblique displacement jack guide rail (11) and a horizontal displacement jack guide rail (12); the movable hopper guide rails include two mutually parallel oblique movable hopper guide rails (13) and two mutually parallel horizontal movable hopper guide rails (14); the oblique movable hopper guide rails (13) are respectively mounted on two oblique beams of an extended oblique cut surface frame formed by a main frame and a second sub-frame, a slider (15) is mounted on the oblique movable hopper guide rail (13), and the horizontal movable hopper guide rail (14) is mounted on the slider of the oblique movable hopper guide rail (13) and is perpendicular to the oblique movable hopper guide rail (13), and a slider (15) is mounted on the horizontal movable hopper guide rail (14). The movable hopper frame is provided with a block (15), and a slider of the horizontal movable hopper guide rail is fixed on the extended inclined surface frame of the movable hopper frame; the oblique displacement jack guide rail (11) is installed on the displacement jack installation oblique beam (1-6) of the first sub-frame (1-2), and a slider (15) is installed on the oblique displacement jack guide rail (11), and the oblique displacement jack guide rail and the oblique movable hopper guide rail (13) are parallel to each other; the horizontal displacement jack guide rail (12) is installed on the lower frame below the movable hopper accommodating portion (1-1-2), and the horizontal displacement jack guide rail (12) and the horizontal movable hopper guide rail (14) are parallel to each other, and a slider (15) is installed on the horizontal jack guide rail (12); The displacement jack (6) comprises a displacement jack arranged horizontally and a displacement jack arranged perpendicular to the horizontal plane; the bottom of the horizontal displacement jack is mounted on the oblique displacement jack guide rail (11) via a slider (15), and the top is fixed on the displacement jack mounting crossbeam (4-4) of the movable hopper frame body (4-1); the bottom of the displacement jack arranged perpendicular to the horizontal plane is mounted on the horizontal displacement jack guide rail (12) via a slider (15), and the top is in contact with the bottom plate of the movable hopper via a supporting pad; The confining pressure loading system comprises a confining pressure jack (7) for providing simulated overlying stratum pressure and horizontal tectonic stress for the surrounding rock materials in the fixed hopper (3) and the movable hopper (4); the bottom of the confining pressure jack (7) is respectively mounted on the confining pressure jack mounting cross beams (1-5) of the second sub-frame, the third sub-frame, the side frame of the movable hopper frame, and the top frame of the movable hopper frame, and the top of the confining pressure jack (7) is respectively mounted with a pressure plate (7-1) for applying confining pressure to the surrounding rock materials in the loading hopper; The displacement jack (6) and the confining pressure jack (7) are used in conjunction with an oil pump (8), an oil pipeline (9) and a power distribution control box (10).

2. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to claim 1 is characterized in that: The included angle between the chamfered surface frame on the upper frame and the bottom plate of the fixed hopper is 30° to 80°.

3. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to claim 1 is characterized in that: There are at least four confining pressure jacks (7), a pad (7-2) is provided between the pressure plate (7-1) and the top of the confining pressure jack (7), and the pressure plate (7-1) is fixedly connected to the top of the confining pressure jack via the pad and screws (7-3).

4. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: The distance between the two oblique movable hopper guide rails (13) is 1.5 to 2 times the distance between the front and rear side surfaces of the upper frame, and the length of the oblique movable hopper guide rail is greater than or equal to the length of the oblique beam of the beveled surface frame on the upper frame; the distance between the two horizontal movable hopper guide rails (14) is 0.6 to 0.8 times the length of the oblique beam of the beveled surface frame on the upper frame, and a slider (15) of one of the horizontal movable hopper guide rails is fixed on the bottom frame bar of the inclined surface frame of the movable hopper frame body.

5. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: The gap between the inclined beam of the chamfered surface frame of the upper frame and the movable hopper (4) is blocked by a rubber strip (16).

6. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: There are 1 to 3 oblique displacement jack guide rails (11), each of which is parallel to each other, and each oblique displacement jack guide rail is provided with a displacement jack (6); there are 1 to 3 horizontal displacement jack guide rails (12), each of which is parallel to each other, and each of which is provided with 1 to 2 displacement jacks (6).

7. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: The support frame (1) and the movable hopper frame are welded from angle steels, the side panels of the fixed hopper (3) and the movable hopper (4) are made of tempered glass, and the bottom panels of the fixed hopper (3) and the movable hopper (4) and the pressure plates of the confining pressure jacks are made of steel plates.

8. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: The bottom of the lower frame is provided with a universal wheel (17).

9. The mechanical behavior characteristics simulation test device for cross-fault tunnels under different burial depths and different tectonic stresses according to any one of claims 1 to 3, characterized in that: The volume of the fixed hopper (3) is greater than the volume of the movable hopper (4).

10. A method for testing the mechanical behavior characteristics of cross-fault tunnels under different burial depths and different tectonic stresses, characterized by: The method is performed on the basis of using the simulation test device according to any one of claims 1 to 9, and comprises the following steps: ① Brush a layer of engine oil on the inner wall of the loading hopper of the simulation test device, adjust the position of the movable hopper of the simulation test device according to the test requirements, install a displacement meter on the simulation test device, lay surrounding rock materials in the loading hopper of the simulation test device, and install lining models, strain gauges and earth pressure cells in the surrounding rock materials during the laying of surrounding rock materials; ② After the surrounding rock material is laid to the required height for the test, it is left to stand until the surrounding rock material reaches the required strength for the test. According to the test needs, the oil pump is turned on to control the confining pressure jack to apply vertical and horizontal pressure to the surrounding rock material to simulate the overlying stratum pressure and tectonic stress respectively; by adjusting the magnitude of the vertical and horizontal pressure applied by the confining pressure jack to the surrounding rock material, different burial depths and different tectonic stress conditions are simulated; ③ According to the test needs, the oil pump is turned on to control the displacement jack to provide power for the horizontal and / or longitudinal movement of the movable bucket. The monitoring instrument connected with the strain gauge and the earth pressure box is used to monitor the stress and strain data of the movable bucket when it moves horizontally and / or longitudinally under different burial depths and different structural stresses in real time. At the same time, the displacement meter is used to measure the horizontal and longitudinal movement distance of the movable bucket in real time; ④ By analyzing the stress, strain and displacement data collected in step ③, the mechanical behavior characteristics of the tunnel under different overlying formation pressures and different tectonic stress conditions, such as strike-slip faults, normal-reverse faults or composite dislocations, are obtained.

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