Full-scale test device for bearing performance of subsurface tunnel

Abstract

The invention belongs to the technical field of large-scale structure test equipment, and particularly relates to a bored tunnel bearing performance full-scale test device which comprises an annular test piece arranged in the center, an integrated counter-force system is coaxially arranged on the outer side of the annular test piece, and a three-dimensional electromagnetic space positioning system is arranged between the integrated counter-force system and the annular test piece. The three-dimensional electromagnetic space positioning system is provided with a plurality of loading systems, the three-dimensional electromagnetic space positioning system is used for adjusting the heights and horizontal positions of the plurality of loading systems, and the plurality of loading systems are circumferentially arranged on the outer side of the annular test piece; the movable end of the loading system is in contact with the outer wall of the annular test piece through a cushion block; the annular test piece is placed on the cushion layer structure; and the three-dimensional electromagnetic space positioning system and the loading system are connected with a device control system. According to the device, free movement of the loading system at vertical and horizontal annular positions can be realized through the three-dimensional electromagnetic space positioning system, and position adjustment of a loading point in a three-dimensional space can be realized by matching with a cushion block.

Description

Technical Field

[0001] This invention belongs to the technical field of large-scale structural testing equipment, and in particular relates to a full-scale testing device for the bearing capacity of mined tunnels. Background Technology

[0002] As the scale of various tunnels continues to grow, tunnels constructed in the early stages are gradually showing signs of deformation and cracking due to various factors, becoming key maintenance targets and drawing significant attention to the overall safety of tunnel structures. Currently, empirical observation, theoretical calculation and analysis, numerical calculation, and similar model tests are the main methods used by experts and scholars to judge and analyze the structural condition of mined tunnels and assess safety risks.

[0003] However, in practical applications, the inevitable simplification or omission of some parameters, especially in numerical calculations and similar model experiments, may lead to biases in the analysis results.

[0004] Full-scale testing can reproduce tunnel structures and defects at a 1:1 scale, making it a powerful method for analyzing tunnel structural performance. However, current full-scale testing platforms for shield tunnels are insufficient to meet testing requirements. For example, the loading points of existing full-scale testing platforms are usually fixed and cannot be flexibly adjusted according to testing needs, deviating from actual working conditions and leading to decreased testing accuracy. Therefore, there is an urgent need for a full-scale testing device for the bearing capacity of mined tunnels. Summary of the Invention

[0005] The purpose of this invention is to provide a full-scale testing device for the bearing capacity of mined tunnels to solve the above-mentioned problems.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A full-scale test device for the bearing capacity of a mined tunnel includes an annular specimen set at the center, an integrated reaction system coaxially arranged on the outer side of the annular specimen, a three-dimensional electromagnetic spatial positioning system between the integrated reaction system and the annular specimen, a plurality of loading systems arranged in the three-dimensional electromagnetic spatial positioning system, the three-dimensional electromagnetic spatial positioning system being used to adjust the height and horizontal position of the plurality of loading systems, the plurality of loading systems being arranged circumferentially on the outer side of the annular specimen;

[0008] The movable end of the loading system contacts the outer wall of the annular specimen through a pad;

[0009] The annular specimen was placed on the padding structure;

[0010] The three-dimensional electromagnetic spatial positioning system and the loading system are connected to a device control system.

[0011] Optionally, the integrated reaction system is a circular sunken foundation pit, the integrated reaction system is a cast-in-place reinforced concrete structure, and the inner wall of the integrated reaction system is provided with a waterproof structure.

[0012] Optionally, the three-dimensional electromagnetic spatial positioning system includes several vertical electromagnetic slide rails, which are circumferentially spaced and embedded in the inner wall of the integrated reaction system.

[0013] Several vertical electromagnetic slide rails are fixed to several circumferential electromagnetic slide rails that are equally spaced along the height direction. Loading system mounting sliders that match the number of loading systems are slidably fitted on the circumferential electromagnetic slide rails, and the loading system mounting sliders correspond one-to-one with the loading systems.

[0014] Optionally, a connecting pad is provided between the circumferential electromagnetic slide rail and the vertical electromagnetic slide rail, and the two ends of the connecting pad are respectively fixed to the circumferential electromagnetic slide rail and the vertical electromagnetic slide rail.

[0015] Optionally, the loading system includes a jack, the hydraulic connection end of which is fixed to a corresponding loading system mounting slider, and a pressure sensing end is provided at the top of the jack, which contacts a corresponding pad.

[0016] Optionally, the pressure sensing end is a pressure displacement sensor, the movable end of the pressure displacement sensor is in contact with the corresponding pad, the fixed end of the pressure displacement sensor is fixed to the top of the jack, and the pressure displacement sensor is electrically connected to the device control system.

[0017] Optionally, the padding structure includes a waterstop strip, the top of which is fixed with two spaced steel plates, the two steel plates forming a cavity for filling with explosion-proof sealing oil, and the top steel plate for placing annular test specimens.

[0018] Optionally, two circumferential electromagnetic slide rails are arranged along the height direction. Every two loading systems located in the same vertical direction constitute a loading group. Each loading group corresponds to one pad block, and the number of loading groups is 24.

[0019] Optionally, the integrated reaction system has an inner diameter of 20m and a depth of 4m, and the waterproof structure is provided in two layers.

[0020] Optionally, a laser positioning device is installed on the loading system mounting slider.

[0021] Compared with the prior art, the present invention has the following advantages and technical effects:

[0022] In use, this device can be assembled based on annular specimens, thus enabling performance tests on mined tunnels of different sizes and cross-sectional styles. It can also conduct loading tests on large concrete components with various cross-sectional forms, such as shield tunnels, pipe galleries, and pipelines. The three-dimensional electromagnetic spatial positioning system allows for free movement of the loading system in both vertical and horizontal circumferential directions. Combined with pads, the loading point can be adjusted in three-dimensional space, meeting the loading requirements of different types of mined tunnel specimens and other large structural specimens, overcoming the limitation of existing full-scale test platforms where the loading point cannot be freely adjusted. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a top view of the structure of the present invention;

[0025] Figure 2 This is a cross-sectional view of the structure of the present invention;

[0026] Figure 3 This is a schematic diagram of the loading system structure of the present invention;

[0027] Figure 4 This is a schematic cross-sectional view of the cushion layer structure of the present invention;

[0028] Figure 5 This is a schematic diagram of the three-dimensional electromagnetic spatial positioning system of the present invention;

[0029] Figure 6 This is a schematic diagram of the pad structure in Embodiment 2 of the present invention;

[0030] The components include: 1. Device control system; 2. Three-dimensional electromagnetic spatial positioning system; 3. Loading system; 4. Integrated reaction system; 5. Cushion structure; 6. Cushion block; 21. Vertical electromagnetic slide rail; 22. Circumferential electromagnetic slide rail; 23. Connecting pad block; 24. Loading system mounting slider; 31. Hydraulic connection end; 32. Jack top; 33. Pressure sensing end; 34. Pressure displacement sensor; 51. Steel plate; 52. Waterstop strip; 53. Explosion-proof sealing oil; 61. Telescopic support arm fixing plate; 62. Screw; 63. Limit slider; 64. Smooth rod. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1:

[0034] Reference Figures 1 to 5 This invention discloses a full-scale test device for the bearing capacity of a mined tunnel, including an annular specimen set at the center, an integrated reaction system 4 coaxially set on the outer side of the annular specimen, a three-dimensional electromagnetic space positioning system 2 set between the integrated reaction system 4 and the annular specimen, a plurality of loading systems 3 set on the three-dimensional electromagnetic space positioning system 2, the three-dimensional electromagnetic space positioning system 2 is used to adjust the height and horizontal position of the plurality of loading systems 3, and the plurality of loading systems 3 are circumferentially set on the outer side of the annular specimen;

[0035] The active end of the loading system 3 contacts the outer wall of the annular specimen through the pad 6;

[0036] The annular specimen was placed on the padding structure 5;

[0037] The three-dimensional electromagnetic spatial positioning system 2 and the loading system 3 are connected to the device control system 1.

[0038] In use, this device can be assembled based on annular specimens, thus enabling performance tests on mined tunnels of different sizes and cross-sectional styles. It can also conduct loading tests on large concrete components with various cross-sectional forms, such as shield tunnels, pipe galleries, and pipelines. The three-dimensional electromagnetic spatial positioning system 2 allows the loading system 3 to move freely in both vertical and horizontal circumferential directions. Combined with the pads 6, it allows for three-dimensional spatial position adjustment, thereby meeting the loading requirements of different types of mined tunnel specimens and other large structural specimens, overcoming the limitation of existing full-scale test platforms where the loading points cannot be freely adjusted.

[0039] The device control system 1 consists of a control terminal and an integrated oil source servo control terminal. The control console of device control system 1 embeds a load control system, a positioning control system, and a data acquisition system. The load control system includes a load calculation module, allowing users to input parameters such as formation and burial depth. This device control system 1 automatically calculates the load, converting formation pressure into point pressure values, ensuring load accuracy of no less than 92%. It also features one-button pause and pressure holding functions, facilitating user observation of experimental phenomena.

[0040] As an optional implementation, the integrated reaction system 4 is a circular sunken foundation pit, the integrated reaction system 4 is a cast-in-place reinforced concrete structure, and the inner wall of the integrated reaction system 4 is equipped with a waterproof structure.

[0041] This invention adopts an integrated design of a sunken reaction frame and reaction wall. By setting up a waterproof structure and using a waterproof hydraulic jack as the core component of the loading system 3, it can simulate the external water environment of the specimen, thereby enabling observation of the entire process of specimen deformation, cracking and leakage.

[0042] As an optional implementation, the three-dimensional electromagnetic spatial positioning system 2 includes several vertical electromagnetic slide rails 21, which are arranged at equal intervals around the circumference and are embedded in the inner wall of the integrated reaction system 4.

[0043] Several vertical electromagnetic slide rails 21 are fixedly connected to several circumferential electromagnetic slide rails 22 that are equally spaced along the height direction. Loading system mounting sliders 24, matching the number of loading systems 3, slide on the circumferential electromagnetic slide rails 22. The loading system mounting sliders 24 correspond one-to-one with the loading systems 3.

[0044] As an optional implementation, a connecting pad 23 is provided between the circumferential electromagnetic slide rail 22 and the vertical electromagnetic slide rail 21, with both ends of the connecting pad 23 fixed to the circumferential electromagnetic slide rail 22 and the vertical electromagnetic slide rail 21, respectively.

[0045] As an optional implementation, the loading system 3 includes a jack, the hydraulic connection end 31 of which is fixed to the corresponding loading system mounting slider 24, and the top end 32 of the jack is provided with a pressure sensing end 33, which contacts the corresponding pad 6.

[0046] As an optional implementation, the pressure sensing end 33 is a pressure displacement sensor 34. The movable end of the pressure displacement sensor 34 contacts the corresponding pad 6, and the fixed end of the pressure displacement sensor 34 is fixed to the top end 32 of the jack. The pressure displacement sensor 34 is electrically connected to the device control system 1.

[0047] The loading system 3 consists of several bidirectional large-tonnage jacks, which have good waterproof performance and can meet the requirements for underwater operation. At the same time, the loading system 3 is connected to the servo oil source control cabinet and operates according to control signals.

[0048] The loading system 3 includes a hydraulic connection end 31, a jack top end 32, a pressure sensing end 33, and a pressure displacement sensor 34.

[0049] A pad 6 is provided between the loading system 3 and the outer wall of the specimen. The pad 6 is used to compensate for the distance between the top 32 of the jack of the loading system 3 and the outer wall of the specimen. It is suitable for situations where the loading system 3 reaches the limit length but the loading force does not reach the preset value. By adding the pad 6, the loading system 3 can easily transfer the loading force to the specimen.

[0050] As an optional implementation, the pad structure 5 includes a waterstop 52, with two spaced steel plates 51 fixed to the top of the waterstop 52. The two steel plates 51 enclose a cavity for filling with explosion-proof sealing oil 53, and the top steel plate 51 is used to place an annular specimen.

[0051] The cushion structure 5 is a self-sealing liquid-sealed annular support. This support consists of a 3-layer structure, with a waterstop 52 at the bottom and two layers of steel plates 51 on top. Explosion-proof sealing oil 53 is filled between the steel plates 51 to reduce friction and provide a sealing effect, thus providing an environment suitable for underwater testing. At the same time, the steel plates 51 are replaceable parts. If the support steel plates 51 are damaged after the on-site casting of the test specimen, they can be disassembled and replaced.

[0052] Furthermore, the area of ​​the cushion structure 5 is sufficient. When casting the specimen on-site, a pad can be placed on the steel plate 51, and the specimen can be cast on the pad. If it is necessary to fix the template, it can be welded to the steel plate. After the specimen is made, it can be removed at will.

[0053] As an optional implementation, two circumferential electromagnetic slide rails 22 are arranged along the height direction. Every two loading systems 3 located in the same vertical direction constitute a loading group. Each loading group corresponds to a pad block 6, and the number of loading groups is 24.

[0054] In this embodiment, the three-dimensional electromagnetic spatial positioning system 2 consists of two circumferential electromagnetic slide rails 22 and twenty-four vertical electromagnetic slide rails 21. The vertical electromagnetic slide rails 21 are fixed at equal intervals to the reaction structure wall of the integrated reaction system 4. The two circumferential electromagnetic slide rails 22 are connected to the twenty-four vertical electromagnetic slide rails 21. The loading system 3 is installed on the circumferential electromagnetic slide rails 22. The loading system 3 moves up and down by controlling the circumferential electromagnetic slide rails 22 along the vertical electromagnetic slide rails 21. The loading system mounting slider 24 on the circumferential electromagnetic slide rails 22 moves to adjust the horizontal position of the loading system 3. The combination of these two methods allows for the adjustment of the loading system 3's position in three-dimensional space, thus adapting to tunnel specimens with different cross-sectional shapes. Simultaneously, a laser positioning device is installed on the loading system mounting slider 24, using the center point of the excavation pit as a reference point for auxiliary positioning.

[0055] The device control system 1 includes a positioning system. This system, based on the specimen's cross-sectional shape and deformation during the test, actively adjusts the positions of each loading system 3 via a three-dimensional electromagnetic spatial positioning system 2. This ensures that each loading point remains tangent to the specimen's contact surface, guaranteeing both test effectiveness and safety. The test data analysis system provides multi-channel interfaces, enabling real-time acquisition of various test data and automatic display of any abnormal data.

[0056] Among them, the integrated oil source servo control terminal of the device control system 1 consists of 12 integrated oil source servo control cabinets of the same specifications, which are placed at equal intervals to ensure that the control of each load is synchronized.

[0057] Twenty-four vertical electromagnetic rails 21 are installed at equal intervals on the integrated reaction system 4, thus this embodiment has a 24-point asymmetric loading capability.

[0058] As an optional implementation, the integrated reaction system 4 has an inner diameter of 20m and a depth of 4m, with two layers of waterproof structure.

[0059] The integrated reaction system 4 is a circular sunken pit with a diameter of 20m and a depth of 4m. It consists of a reaction well wall and a waterproof system. The reaction well wall is integrally cast from a reaction steel frame and C80 concrete, and is internally lined with two layers of waterproofing to ensure that the well wall will not deform or be damaged during the test. It also has the function of underwater loading.

[0060] As an optional implementation, a laser positioning device is mounted on the loading system mounting slider 24.

[0061] The steps for conducting experiments using this device are as follows:

[0062] 1) Develop test plan: This includes specimen dimensions, loading scheme, operation steps, etc., to facilitate the preliminary preparation work such as custom servo control system, loading system, three-dimensional electromagnetic space positioning system settings and specimen placement;

[0063] 2) Specimen preparation: Adjust the position of the specimen support components according to the test plan, then place the pad, install the model template, and pour the specimen on site.

[0064] 3) Install telescopic support arms and loading devices: According to the test plan, install an appropriate number of telescopic support arms at each loading point, then install the loading devices. After confirming that they are secure, use the electromagnetic spatial positioning system to position the loading devices. Then adjust the telescopic arms to ensure that the loading jacks are tangent to the surface of the specimen. Next, install the load distribution device by connecting the front end of the jacks to the pre-reserved slot at the front end of the load distribution device. Finally, adjust the telescopic support arms and the lifting amount of the jacks to ensure that the load distribution device is in contact with the specimen.

[0065] 4) Set up data acquisition instruments: Set up data acquisition equipment on the specimen. Common data acquisition instruments include steel stress strain gauges, external strain gauges, concrete strain sensors and various displacement gauges. The data acquisition instruments are set up according to the test plan, and the other end is connected to the control console.

[0066] 5) Servo control system parameter settings:

[0067] Input the relevant parameters according to the test plan, and after the system calculates, set the load value for each point, as well as parameters such as loading accuracy, loading speed, and peak failure strength determination.

[0068] 6) Data Acquisition System Settings: Users can set the parameters of the data acquisition system on the control platform, such as acquisition accuracy, frequency, and type. Users can also configure a computer for independent data acquisition.

[0069] 7) Test loading and data acquisition: Start loading according to the test plan. If the data acquisition system is embedded in the control system, select "Start Loading" directly. The system will automatically store various test data. If it is not embedded, the user needs to start data acquisition manually.

[0070] Example 2:

[0071] refer to Figure 6 The difference between this embodiment and Embodiment 1 is that the pad 6 includes a telescopic support arm fixing plate 61 fixed to the side wall of the annular specimen. The telescopic support arm fixing plate 61 has a lead screw 62 and three smooth rods 64. The lead screw 62 and the three smooth rods 64 are respectively set at the four corners of the telescopic support arm fixing plate 61. The smooth rods 64 are fixed to the telescopic support arm fixing plate 61. The lead screw 62 is rotatably engaged with the telescopic support arm fixing plate 61. The three smooth rods 64 are slidably engaged with the same limiting slider 63. The limiting slider 63 is threadedly engaged with the lead screw 62. The limiting slider 63 is in contact with the corresponding moving end of the loading system 3.

[0072] The pad block 6 consists of a telescopic support arm fixing plate 61, a lead screw 62, a limiting slider 63, and a smooth rod 64. Each lead screw 62 and smooth rod 64 is 1.5m long. The lead screw 62 provides the limiting function. Before use, after adjusting the position of the limiting slider 63, the gap between the telescopic support arm fixing plate 61 and the limiting slider 63 can be filled by pouring concrete to ensure uniform force transmission.

[0073] The adjustable length of the pad 6 allows for flexible compensation of the displacement of the loading system 3.

[0074] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0075] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A full-scale test device for the bearing capacity of a mined tunnel, comprising a ring-shaped specimen positioned at the center, characterized in that, An integrated reaction system (4) is coaxially arranged on the outer side of the annular specimen. A three-dimensional electromagnetic space positioning system (2) is arranged between the integrated reaction system (4) and the annular specimen. The three-dimensional electromagnetic space positioning system (2) is equipped with several loading systems (3). The three-dimensional electromagnetic space positioning system (2) is used to adjust the height and horizontal position of the several loading systems (3). The several loading systems (3) are arranged circumferentially on the outer side of the annular specimen. The movable end of the loading system (3) contacts the outer wall of the annular specimen through the pad (6); The annular specimen is placed on the padding structure (5); The three-dimensional electromagnetic spatial positioning system (2) and the loading system (3) are connected to a device control system (1).

2. The full-scale test device for bearing capacity of mined tunnels according to claim 1, characterized in that: The integrated reaction system (4) is a circular sunken foundation pit. The integrated reaction system (4) is a cast reinforced concrete structure, and the inner wall of the integrated reaction system (4) is equipped with a waterproof structure.

3. The full-scale test device for bearing capacity of mined tunnels according to claim 1, characterized in that: The three-dimensional electromagnetic spatial positioning system (2) includes several vertical electromagnetic slide rails (21), which are arranged at equal intervals around the circumference. The vertical electromagnetic slide rails (21) are embedded in the inner wall of the integrated reaction system (4). Several vertical electromagnetic slide rails (21) are fixed to several circumferential electromagnetic slide rails (22) that are equally spaced along the height direction. The circumferential electromagnetic slide rails (22) are slidably fitted with loading system mounting sliders (24) that match the number of loading systems (3). The loading system mounting sliders (24) correspond one-to-one with the loading systems (3).

4. The full-scale test device for the bearing capacity of a mined tunnel according to claim 3, characterized in that, A connecting pad (23) is provided between the circumferential electromagnetic slide rail (22) and the vertical electromagnetic slide rail (21), and the two ends of the connecting pad (23) are fixed to the circumferential electromagnetic slide rail (22) and the vertical electromagnetic slide rail (21) respectively.

5. The full-scale test device for bearing capacity of mined tunnels according to claim 3, characterized in that: The loading system (3) includes a jack, the hydraulic connection end (31) of the jack is fixed to the corresponding loading system mounting slider (24), and the top end (32) of the jack is provided with a pressure sensing end (33), which is in contact with the corresponding pad (6).

6. The full-scale test device for bearing capacity of mined tunnels according to claim 5, characterized in that: The pressure sensing end (33) is a pressure displacement sensor (34). The movable end of the pressure displacement sensor (34) is in contact with the corresponding pad (6). The fixed end of the pressure displacement sensor (34) is fixed to the top of the jack (32). The pressure displacement sensor (34) is electrically connected to the device control system (1).

7. The full-scale test device for bearing capacity of mined tunnels according to claim 1, characterized in that: The padding structure (5) includes a waterstop (52), and two spaced steel plates (51) are fixed to the top of the waterstop (52). The two steel plates (51) together form a cavity for filling with explosion-proof sealing oil (53). The steel plate (51) at the top is used to place the annular specimen.

8. The full-scale test device for bearing capacity of mined tunnels according to claim 3, characterized in that: The circumferential electromagnetic slide rail (22) is arranged in two tracks along the height direction. Every two loading systems (3) located in the same vertical direction constitute a loading group. Each loading group corresponds to one pad (6). The number of loading groups is 24.

9. A full-scale test device for the bearing capacity of a mined tunnel according to claim 2, characterized in that: The integrated reaction system (4) has an inner diameter of 20m and a depth of 4m, and the waterproof structure is provided in two layers.

10. A full-scale test device for the bearing capacity of a mined tunnel according to claim 3, characterized in that: The loading system is mounted on a slider (24) with a laser positioning device installed.

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