Test device and test method for simulating tunnel excavation unloading driving process

Abstract

The application provides a test device and a test method for simulating a tunnel excavation unloading driving process, and relates to the technical field of geotechnical engineering, and comprises: a loading simulation box for pressurizing a model main body, and a simulation tunnel is formed in the model main body; a loading and unloading assembly is installed in the simulation tunnel, a plurality of telescopic units are sequentially distributed along the axial direction of the loading and unloading assembly and are telescopic along the radial direction of the loading and unloading assembly, the plurality of telescopic units are suitable for being loaded into the simulation tunnel and being extended to press against the inner circumferential wall of the simulation tunnel, and the plurality of telescopic units are suitable for being sequentially contracted to be separated from the inner circumferential wall of the simulation tunnel; a strain adjusting system is used for adjusting the loading pressure of the loading simulation box according to an actual working condition, and is used for detecting the stress change of the model main body in the process that the plurality of telescopic units are sequentially contracted. The test device for simulating the tunnel excavation unloading driving process of the embodiment of the application can accurately simulate the dynamic unloading characteristics in the tunnel driving process, and can guarantee the safety of tunnel construction and the stability of long-term service.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering technology, and in particular to a test apparatus and test method for simulating the tunnel excavation and unloading process. Background Technology

[0002] The deformation and stress redistribution of surrounding rock during tunnel excavation and unloading are core research topics for tunnel construction safety and long-term service stability. Accurate model tests are needed to recreate the stress environment and dynamic unloading process. Existing test devices simulating tunnel excavation and unloading often perform one-time unloading in simulations, failing to reproduce the dynamic unloading characteristics during tunnel excavation. This results in low reliability of the test data obtained, affecting tunnel construction safety and long-term service stability, indicating room for improvement. Summary of the Invention

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a test device for simulating the unloading process of tunnel excavation. The device has a simple structure and can accurately simulate the dynamic unloading characteristics during tunnel excavation, thereby ensuring the reliability of the test data measured by the test device and guaranteeing the safety of tunnel construction and the stability of long-term service.

[0004] An experimental apparatus for simulating the excavation and unloading process of a tunnel according to an embodiment of the present invention includes: a loading simulation box; a model body installed inside the loading simulation box, the loading simulation box being used to pressurize the model body, and a simulated tunnel being formed inside the model body; a loading and unloading assembly installed inside the simulated tunnel, the loading and unloading assembly including multiple telescopic units, the multiple telescopic units being sequentially distributed along the axial direction of the loading and unloading assembly and being radially expandable and contractible, the multiple telescopic units being adapted to be inserted into the simulated tunnel and extend out to press against the inner peripheral wall of the simulated tunnel, and the multiple telescopic units being adapted to retract sequentially to separate from the inner peripheral wall of the simulated tunnel; and a strain adjustment system, the strain adjustment system being used to adjust the loading pressure of the loading simulation box according to the actual working conditions, and to detect the stress change of the model body during the sequential retraction of the multiple telescopic units.

[0005] The test device for simulating the unloading and tunneling process of a tunnel according to an embodiment of the present invention applies pressure to the main body of the model by loading a simulation box to simulate actual working conditions. An loading and unloading assembly is set inside the simulated tunnel, and multiple telescopic units of the loading and unloading assembly can sequentially contract to separate from the inner wall of the simulated tunnel. This accurately simulates the dynamic unloading characteristics during tunnel excavation. Simultaneously, a strain adjustment system can detect stress changes in the main body of the model during the sequential contraction of multiple telescopic units, thereby ensuring the reliability of the test data measured by the test device, guaranteeing the safety of tunnel construction and the stability of long-term service, resulting in better performance and a wider range of applications.

[0006] According to some embodiments of the present invention, a test device for simulating the tunnel excavation and unloading process includes a telescopic unit comprising multiple telescopic members and multiple support plates. The multiple telescopic members are spaced apart circumferentially along the loading and unloading assembly. The multiple telescopic members and the multiple support plates are arranged in a one-to-one correspondence. Each support plate is installed at one end of the corresponding telescopic member. The telescopic member is used to drive the support plate to move radially.

[0007] According to some embodiments of the present invention, the test device for simulating the tunnel excavation and unloading process includes multiple support plates comprising multiple type I plates and multiple type II plates. The type I plate is constructed as a fan-shaped ring with an outer ring central angle smaller than the inner ring central angle, and the type II plate is constructed as a fan-shaped ring with an outer ring central angle larger than the inner ring central angle. The multiple type I plates and the multiple type II plates are staggered and distributed sequentially along the circumferential direction. Wherein, the first type plate is adapted to radially contract before the second type plate, and the second type plate is adapted to radially extend before the first type plate.

[0008] According to some embodiments of the present invention, the test device for simulating the tunnel excavation and unloading process includes a mounting column, a plurality of the telescopic units being distributed axially on the outer peripheral wall of the mounting column, and the other end of the plurality of telescopic members being connected to the mounting column. The mounting column is coaxially arranged with the simulated tunnel.

[0009] According to some embodiments of the present invention, a test apparatus for simulating the unloading and tunneling process of a tunnel excavation includes a loading simulation box comprising a box body and a plurality of pressurizing components. The box body is located outside the loading simulation box, and the plurality of pressurizing components are arranged around the inner wall of the box body, and the plurality of pressurizing components are used to pressurize the model body.

[0010] According to some embodiments of the present invention, the test device for simulating the unloading and tunneling process of tunnel excavation includes a loading simulation box further comprising four pressure plates. The four pressure plates are installed inside the box and are respectively arranged corresponding to the inner bottom wall, inner top wall, left inner side wall and right inner side wall of the box. One end of the pressure member is connected to the box and the other end is connected to the pressure plate. The pressure member is adapted to drive the pressure plate to press against the model body.

[0011] According to some embodiments of the present invention, the test apparatus for simulating the unloading and tunneling process of a tunnel excavation includes a loading simulation box further comprising a support frame, the support frame being installed inside the box and supported between the box and the model body, the support frame forming an avoidance area, and the pressure plate being adapted to move through the avoidance area to press against the model body.

[0012] According to some embodiments of the present invention, in a test apparatus for simulating the unloading and tunneling process of a tunnel excavation, the front side of the support frame is configured as an observation window, and the strain adjustment system is adapted to detect stress changes in the model body through the observation window.

[0013] According to some embodiments of the present invention, in the test apparatus for simulating the tunnel excavation and unloading process, the rear side of the support frame is a mounting plate, and one end of the loading and unloading assembly is detachably mounted on the mounting plate along the axial direction. And / or, the outer peripheral wall of the housing is formed with a first reinforcing member.

[0014] The present invention also proposes an experimental method for simulating the tunnel excavation and unloading process.

[0015] The test method for simulating tunnel excavation and unloading tunneling process according to embodiments of the present invention is applicable to the test apparatus for simulating tunnel excavation and unloading tunneling process described in any of the above claims, and the test method includes: Multiple telescopic units of the loading and unloading assembly are controlled to extend and press against the inner peripheral wall of the simulated tunnel; The loading simulation box is controlled to apply simulated pressure to the model body, and the simulated pressure reaches the target pressure of the actual working tunnel. The multiple telescopic units of the loading and unloading assembly are controlled to retract sequentially to gradually remove the support for the inner peripheral wall of the simulated tunnel along the axial direction. The stress changes of the model body are obtained during the sequential contraction of the multiple expansion units, and the stress changes are analyzed.

[0016] The test method for simulating tunnel excavation and unloading process and the test device for simulating tunnel excavation and unloading process described above have the same advantages over the prior art, and will not be repeated here.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of a test device for simulating the tunnel excavation and unloading process according to an embodiment of the present invention; Figure 2 This is a partial cross-sectional view of a test apparatus for simulating the tunnel excavation and unloading process according to an embodiment of the present invention; Figure 3 This is a partial structural schematic diagram of a test device for simulating the tunnel excavation and unloading process according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the loading / unloading component according to an embodiment of the present invention. Figure 1 ; Figure 5 This is a schematic diagram of the loading / unloading component according to an embodiment of the present invention. Figure 2 ; Figure 6 This is a flowchart of an experimental method for simulating the tunnel excavation and unloading process according to an embodiment of the present invention.

[0019] Figure label: Experimental apparatus 100 simulating the tunnel excavation and unloading process. The simulation chamber 1 includes a base plate 111, a top plate 112, a left side plate 113, a right side plate 114, a main body 115, a connecting part 116, a second reinforcing member 117, a first reinforcing member 118, an observation window 119, a mounting plate 120, a pressure member 12, a pressure plate 13, a support frame 14, and a connecting part 15. Model body 2, simulated tunnel 21, Loading / unloading component 3, mounting column 31, telescopic unit 32, telescopic component 321, type I plate 322, type II plate 323, wiring harness 33, strain adjustment system 4. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not 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 the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] The following is for reference. Figures 1-5 The experimental apparatus 100 described in this embodiment of the invention, which simulates the unloading process of tunnel excavation, has a simple structure and can accurately simulate the dynamic unloading characteristics during tunnel excavation, thereby ensuring the reliability of the experimental data measured by the experimental apparatus and guaranteeing the safety of tunnel construction and the stability of long-term service.

[0024] like Figures 1-5 As shown, a test apparatus 100 for simulating the tunnel excavation and unloading process according to an embodiment of the present invention includes: a loading simulation box 1, a model body 2, a loading and unloading component 3, and a strain adjustment system 4.

[0025] The model body 2 is installed inside the loading simulation box 1, which is used to pressurize the model body 2. A simulated tunnel 21 is formed inside the model body 2. The loading and unloading assembly 3 is installed inside the simulated tunnel 21. The loading and unloading assembly 3 includes multiple telescopic units 32. The multiple telescopic units 32 are distributed sequentially along the axial direction of the loading and unloading assembly 3 and are radially expandable and contractible. The multiple telescopic units 32 are adapted to be inserted into the simulated tunnel 21 and extend out to press against the inner peripheral wall of the simulated tunnel 21. The multiple telescopic units 32 are adapted to retract sequentially to separate from the inner peripheral wall of the simulated tunnel 21. The strain adjustment system 4 is used to adjust the loading pressure of the loading simulation box 1 according to the actual working conditions and to detect the stress change of the model body 2 during the sequential retraction of the multiple telescopic units 32.

[0026] Specifically, the test device 100 for simulating the tunnel excavation and unloading process is equipped with a loading simulation box 1 and a model body 2. The model body 2 is a cubic specimen that can be cast before the test. A simulated tunnel 21 is formed inside the model body 2. The simulated tunnel 21 is cylindrical and runs horizontally through the model body 2. The loading simulation box 1 is located on the outermost side of the test device. During the test, the model body 2 is installed inside the loading simulation box 1. The loading simulation box 1 can apply pressure to the model body 2 so that the stress state of the model body 2 can be consistent with the actual working conditions, thereby ensuring the accuracy of the test results.

[0027] Furthermore, the test device 100 for simulating the tunnel excavation and unloading process is also equipped with a loading and unloading component 3. The loading and unloading component 3 can be installed inside the simulated tunnel 21 and is detachably connected to the loading simulation box 1. The loading and unloading component 3 is equipped with multiple telescopic units 32, that is, the telescopic units 32 can be set to two, three or four, etc. The multiple telescopic units 32 are distributed along the axial direction of the simulated tunnel 21. Before the test, the loading and unloading component 3 can be installed inside the simulated tunnel 21 and the multiple telescopic units 32 can be extended to press against and support the inner peripheral wall of the simulated tunnel 21 to simulate the shape of the tunnel 21 before excavation.

[0028] Furthermore, the test device 100 simulating the tunnel excavation and unloading process is equipped with a strain adjustment system 4. The strain adjustment system 4 may be equipped with a high-speed camera and a control device. The control device can control the loading simulation box 1 and the loading and unloading component 3, so that when the loading simulation box 1 applies pressure to the model body 2 and during the test, the strain adjustment system 4 can obtain the stress change state of the model body 2 through the high-speed camera and transmit it to the control device. The control device can then control the loading simulation box 1 and the loading and unloading component 3 based on the acquired data, thereby obtaining the deformation characteristics and stress evolution law during the tunnel excavation and unloading process.

[0029] In addition, before the test, the strain adjustment system 4 can adjust the loading pressure of the loading simulation box 1 according to the actual working conditions to ensure that the test results are consistent with the actual situation. During the test, the strain adjustment system 4 can control the multiple telescopic units 32 of the loading and unloading component 3 to contract sequentially along the axial direction of the simulated tunnel 21, so that the loading and unloading component 3 can remove the supporting force on the inner wall of the simulated tunnel 21 sequentially along the axial direction, thereby accurately simulating the dynamic unloading characteristics during the tunnel excavation process. At the same time, the strain adjustment system 4 detects the stress change of the model body 2 during the sequential contraction of the multiple telescopic units 32, so that the user can obtain the deformation characteristics and stress evolution law during the tunnel excavation unloading process, which can ensure the reliability of the test data measured by the test device, thereby ensuring the safety of tunnel construction and the stability of long-term service.

[0030] According to an embodiment of the present invention, a test device 100 for simulating the unloading and tunneling process of a tunnel excavation applies pressure to the model body 2 by loading a simulation box 1 to simulate actual working conditions. An loading and unloading assembly 3 is set inside the simulated tunnel 21. Multiple telescopic units 32 of the loading and unloading assembly 3 can be sequentially contracted to separate from the inner peripheral wall of the simulated tunnel 21, thereby accurately simulating the dynamic unloading characteristics during the tunnel excavation process. At the same time, the strain adjustment system 4 can detect the stress change of the model body 2 during the sequential contraction of multiple telescopic units 32, thereby ensuring the reliability of the test data measured by the test device, ensuring the safety of tunnel construction and the stability of long-term service, resulting in better performance and a wider range of applications.

[0031] In some embodiments, the telescopic unit 32 includes a plurality of telescopic members 321 and a plurality of support plates. The plurality of telescopic members 321 are spaced apart along the circumference of the loading and unloading assembly 3. The plurality of telescopic members 321 and the plurality of support plates are arranged in a one-to-one correspondence. Each support plate is installed at one end of the corresponding telescopic member 321. The telescopic member 321 is used to drive the support plate to move radially.

[0032] Specifically, the loading / unloading component 3 is provided with multiple telescopic units 32 arranged sequentially along the axial direction, and as shown in the figure. Figures 4-5 As shown, the telescopic unit 32 is provided with multiple telescopic components 321 and multiple support plates. That is, the telescopic components 321 can be set to two, three, or four, and the support plates can also be set to two, three, or four, etc. The multiple telescopic components 321 are distributed circumferentially, and the multiple telescopic components 321 and the multiple support plates are arranged in a one-to-one correspondence, so that each telescopic component 321 has a support plate at one end. Each support plate is installed at the end of the telescopic component 321 near the inner peripheral wall of the simulated tunnel 21, so that each telescopic unit 32 is provided with multiple support plates circumferentially, and the telescopic components 321 extend and retract radially, so that each telescopic component 321 can control the support plate to move radially closer to or away from the inner peripheral wall of the simulated tunnel 21 during the extension and retraction process, and so that the telescopic unit 32 can support the inner peripheral wall of the simulated tunnel 21 circumferentially.

[0033] In actual setup, the telescopic component 321 can be radially contracted during assembly, thereby reducing the overall radial dimension of the loading / unloading assembly 3, facilitating its installation within the simulated tunnel 21. After installation, the telescopic component 321 can be extended, allowing it to drive the support plate against the inner wall of the simulated tunnel 21, thus providing pre-support for the inner wall. During testing, the telescopic components 321 of the multiple telescopic units 32 of the loading / unloading assembly 3 can sequentially contract axially, driving the support plate away from the inner wall of the simulated tunnel 21, thereby removing support from the inner wall and simulating the dynamic unloading characteristics during tunnel excavation.

[0034] In some embodiments, the plurality of support plates include a plurality of primary plates 322 and a plurality of secondary plates 323. The primary plate 322 is configured as a fan-shaped ring with an outer central angle smaller than the inner central angle, and the secondary plate 323 is configured as a fan-shaped ring with an outer central angle larger than the inner central angle. The plurality of primary plates 322 and the plurality of secondary plates 323 are arranged alternately in the circumferential direction. The primary plate 322 is adapted to radially contract before the secondary plate 323, and the secondary plate 323 is adapted to radially extend before the primary plate 322.

[0035] Specifically, the telescopic unit 32 is provided with multiple telescopic components 321 and multiple support plates, and as follows: Figures 4-5 As shown, the multiple support plates include multiple type I plates 322 and multiple type II plates 323. The multiple type I plates 322 and multiple type II plates 323 are distributed sequentially along the circumference. When the telescopic members 321 of the telescopic unit 32 are all extended, the support plates of the multiple telescopic members 321 can be constructed together into a ring. This allows the multiple type I plates 322 and multiple type II plates 323 to press against and support the inner wall of the simulated tunnel 21 when the telescopic unit 32 supports the inner wall of the simulated tunnel 21, thus ensuring the reliability of the support.

[0036] Furthermore, the first type plate 322 is constructed as a fan-shaped ring with an outer ring central angle smaller than the inner ring central angle, meaning the outer ring width of the first type plate 322 is smaller than the inner ring width, resulting in the width of the first type plate 322 gradually decreasing radially outwards. The second type plate 323 is constructed as a fan-shaped ring with an outer ring central angle larger than the inner ring central angle, meaning the outer ring width of the first type plate 322 is larger than the inner ring width, resulting in the width of the first type plate 322 gradually decreasing radially inwards, thereby enabling expansion and contraction... When the support force is removed from the simulated tunnel 21 by unit 32, the telescopic member 321 of the first plate 322 can retract first, and the telescopic member 321 of the second plate 323 can retract later. When the telescopic unit 32 supports the simulated tunnel 21, the telescopic member 321 of the second plate 323 can extend first, and the telescopic member 321 of the first plate 322 can extend later, so as to avoid interference between the first plate 322 and the second plate 323 and ensure the operational reliability of the telescopic unit 32.

[0037] In some embodiments, the loading and unloading assembly 3 further includes a mounting column 31, a plurality of telescopic units 32 are axially distributed on the outer peripheral wall of the mounting column 31, and the other end of the plurality of telescopic members 321 is connected to the mounting column 31, wherein the mounting column 31 is coaxially arranged with the simulated tunnel 21.

[0038] Specifically, the loading component is installed inside the simulated tunnel 21 and is equipped with a mounting column 31. One end of the mounting column 31 can be connected to the loading simulation box 1 through a connector or the like. Multiple telescopic units 32 can be distributed sequentially along the axial direction of the mounting column 31 on the outer peripheral wall of the mounting column 31, so that multiple telescopic units 32 can be installed inside the simulated tunnel 21 through the mounting column 31. When multiple telescopic units 32 are retracted, they can also be spaced apart from the inner peripheral wall of the simulated tunnel 21 through the mounting column 31 to ensure the reliability of removing the support force.

[0039] Furthermore, one end of each of the multiple telescopic components 321 is connected to the support plate, and the other end of each telescopic component 321 can be connected to the mounting column 31. The mounting column 31 can be a hollow column, and the external wiring harness 33 can be inserted inside the mounting column 31 to connect with the multiple telescopic components 321. This allows the strain adjustment system 4 to be electrically connected to the multiple telescopic components 321 to control the extension and retraction of the multiple telescopic components 321, ensuring the reliability of the simulation. The mounting column 31 is coaxially arranged with the simulated tunnel 21, so that the distance between the outer peripheral wall of the mounting column 31 and the inner peripheral wall of the simulated tunnel 21 is the same, so that the length traveled by each telescopic component 321 when it extends is also equal. This ensures the consistency of the supporting force of each telescopic unit 32 on the inner peripheral wall of the simulated tunnel 21, thereby ensuring the accuracy of the simulation.

[0040] In some embodiments, the loading simulation box 1 includes a box body and a plurality of pressurizing components 12. The box body is located outside the loading simulation box 1, and the plurality of pressurizing components 12 are arranged around the inner wall of the box body, and the plurality of pressurizing components 12 are used to pressurize the model body 2.

[0041] Specifically, loading the simulation chamber 1 can pressurize the main body of the model 2, and as... Figures 1-2 As shown, the loading simulation chamber 1 is equipped with a chamber body located on the outermost side of the loading simulation chamber 1, which can provide mounting points and support for the internal structure. The loading simulation chamber 1 is also equipped with multiple pressure-pressurizing components 12, that is, the pressure-pressurizing components 12 can be set to two, three or four, etc., and the multiple pressure-pressurizing components 12 are arranged around the inner wall of the chamber body. One end of the pressure-pressurizing component 12 can be connected to the inner wall of the chamber body, and the other end can extend towards the model body 2 to pressurize the model body 2. The multiple pressure-pressurizing components 12 are arranged around the inner wall of the chamber body, so that the pressure-pressurizing components 12 can be installed on the inner bottom wall, inner top wall, left inner side wall and right inner side wall of the chamber body, etc., so that the model body 2 can be pressurized all around the chamber body to simulate the actual working conditions and improve the accuracy of the test.

[0042] Furthermore, such as Figure 1 As shown, the enclosure is provided with a bottom plate 111, a top plate 112, a left side plate 113, and a right side plate 114. The bottom plate 111 and the top plate 112 are arranged facing each other vertically, and the left side plate 113 and the right side plate 114 are arranged facing each other horizontally. Multiple pressure components 12 can be installed on the inner side of the bottom plate 111, the top plate 112, the left side plate 113, and the right side plate 114 respectively. The left side plate 113 and the right side plate 114 are each provided with a main body 115 and a connecting part 116. The connecting part 116 is located at the upper and lower ends of the main body 115. The connecting part 116 is bent and connected to the main body 115 and extends outward. The top plate 112 can be detachably connected to the connecting part 116 at the upper end of the left side plate 113 and the right side plate 114 through the connecting piece 15. The bottom plate 111 can be detachably connected to the connecting part 116 at the lower end of the left side plate 113 and the right side plate 114 through the connecting piece 15, which facilitates installation.

[0043] In addition, a second reinforcing member 117 is provided between the connecting part 116 and the main body 115. The second reinforcing member 117 can be configured as a reinforcing plate with a triangular structure, which can improve the structural strength between the connecting part 116 and the main body 115, so as to ensure the overall structural strength of the enclosure and improve the reliability of use.

[0044] In some embodiments, the loading simulation box 1 further includes four pressure plates 13. The four pressure plates 13 are installed in the box and are respectively arranged corresponding to the inner bottom wall, inner top wall, left inner side wall and right inner side wall of the box. One end of the pressure member 12 is connected to the box and the other end is connected to the pressure plate 13. The pressure member 12 is adapted to drive the pressure plate 13 to press against the model body 2.

[0045] Specifically, such as Figures 1-2 As shown, the loading simulation box 1 is also equipped with a pressure plate 13. The pressure plate 13 is a plate-shaped structure, and there are four pressure plates 13. The four pressure plates 13 can be respectively set to correspond to the inner bottom wall, inner top wall, left inner side wall and right inner side wall of the box, so that the end of the pressure member 12 set on the inner bottom wall, inner top wall, left inner side wall and right inner side wall away from the box can be connected to the pressure plate 13. In this way, the pressure member 12 can drive the pressure plate 13 to press against the top surface, bottom surface, left side and right side of the model body 2, and the pressure plate 13 can distribute the force of the pressure member 12 evenly to the entire plane of the model body 2 to improve the uniformity of pressure.

[0046] Furthermore, multiple pressure-applying components 12 are correspondingly provided on the inner bottom wall, inner top wall, left inner side wall, and right inner side wall, and the number of pressure-applying components 12 provided on the inner bottom wall, inner top wall, left inner side wall, and right inner side wall is equal. The pressure-applying components 12 provided on the inner bottom wall, inner top wall, left inner side wall, and right inner side wall can be electrically connected to the strain adjustment system 4 respectively, and the pressure-applying components 12 provided on the inner bottom wall, inner top wall, left inner side wall, and right inner side wall can be controlled separately to accurately simulate the stress required by the actual working condition and improve the accuracy of the test results.

[0047] In some embodiments, the loading simulation box 1 further includes a support frame 14, which is installed inside the box and supported between the box and the model body 2. The support frame 14 forms a clearance area, and the pressure plate 13 is adapted to move through the clearance area to press against the model body 2.

[0048] Specifically, such as Figure 3 As shown, the loading simulation box 1 is also equipped with a support frame 14, which is installed inside the box. The model body 2 is located inside the support frame 14, so that the support frame 14 can support the box body, ensuring the overall structural strength of the test device 100 for simulating the tunnel excavation and unloading process, and thus ensuring the reliability of use. The support frame 14 forms a clearance area, which is located on the upper, lower, left and right sides of the support frame 14. That is, the clearance area is set corresponding to the four pressure plates 13, so that when the pressure member 12 drives the pressure plate 13 to run, the pressure plate 13 can move through the clearance area to press against the model body 2, thus ensuring the structural strength while avoiding interference with the movement of the pressure plate 13, thereby improving the reliability of use.

[0049] In some embodiments, the front side of the support frame 14 is configured as an observation window 119, and the strain adjustment system 4 is adapted to detect stress changes in the model body 2 through the observation window 119.

[0050] Specifically, such as Figures 2-3As shown, the support frame 14 is provided with four support columns, which extend along the axial direction of the simulated tunnel 21. The front ends of the four support columns are connected to the front end plate, which can be constructed as an observation window 119. The observation window 119 is set corresponding to the front end of the model body 2. The high-speed camera of the strain adjustment system 4 can be installed on the front side of the loading simulation box 1 and facing the observation window 119, so that the strain adjustment system 4 can detect the stress change of the model body 2 through the observation window 119, so as to ensure the accuracy of the detection results while ensuring the structural strength.

[0051] In some embodiments, the rear side of the support frame 14 is configured as a mounting plate 120, and the loading / unloading assembly 3 is detachably mounted on the mounting plate 120 at one end along the axial direction.

[0052] Specifically, such as Figures 2-3 As shown, the support frame 14 is provided with four support columns, which extend along the axial direction of the simulated tunnel 21. The rear ends of the four support columns are all connected to the rear end plate, which can be constructed as a mounting plate 120. The loading and unloading assembly 3 is provided with mounting columns 31. The rear ends of the mounting columns 31 can be connected to the middle of the mounting plate 120 by bolts or other structures. Bolt installation is convenient and the setup cost is low. This allows the loading and unloading assembly 3 to be detachably installed on the mounting plate 120 at one end along the axial direction, which facilitates the installation, disassembly, and debugging of the loading and unloading assembly 3 and saves test time.

[0053] In other embodiments, the outer peripheral wall of the housing is formed with a first reinforcing member 118.

[0054] Specifically, such as Figures 1-2 As shown, a first reinforcing member 118 is formed on the outer peripheral wall of the box. The first reinforcing member 118 can be constructed as a reinforcing protrusion, and the first reinforcing member 118 is formed on the top, bottom, left and right outer walls of the box, so that the first reinforcing member 118 can be correspondingly set with the pressure member 12 to ensure the structural strength of the box at all parts. There are two first reinforcing members 118 on each side of the box. The two first reinforcing members 118 extend along the diagonal of each side and are staggered to improve the structural strength of each side of the box and ensure the reliability of use.

[0055] The present invention also proposes an experimental method for simulating the tunnel excavation and unloading process.

[0056] The test method for simulating tunnel excavation and unloading tunneling process according to embodiments of the present invention is applicable to the test apparatus 100 for simulating tunnel excavation and unloading tunneling process described above. Figure 6 As shown, the test methods include: S1. Multiple telescopic units 32 of the loading and unloading assembly 3 extend and press against the inner wall of the simulated tunnel 21; S2. Control the loading simulation box 1 to apply simulated pressure to the model body 2, and make the simulated pressure reach the target pressure of the actual working condition tunnel. S3. The multiple telescopic units 32 of the loading and unloading assembly 3 are retracted in sequence to gradually remove the support for the inner wall of the simulated tunnel 21 along the axial direction. S4. Obtain the stress change of the model body 2 during the sequential contraction of multiple expansion units 32, and analyze the stress change.

[0057] Specifically, before conducting the experiment, the main body 2 of the model needs to be fabricated and the loading simulation box 1 needs to be assembled. The process is as follows: According to the similarity ratio of the physical model test, a cubic sample containing a tunnel structure is prefabricated and cast to form the main body 2 of the model. A simulated tunnel 21 is formed inside the main body 2 of the model. The loading and unloading component 3 is placed inside the simulated tunnel 21. The support frame 14 is installed on the bottom wall of the box, and the pressure plate 13 corresponding to the bottom wall of the box is precisely fitted into the avoidance area of ​​the support frame 14. Then, the main body 2 of the model with the loading and unloading component 3 is installed in the support frame 14. The rear end of the mounting column 31 of the loading and unloading component 3 is connected to the center position of the mounting plate 120 of the support frame 14 by bolts to ensure the stability of the structure. At the same time, the front end of the mounting column 31 is tightly fitted to the observation window 119.

[0058] Next, the left side plate 113 and right side plate 114 of the box are connected to the bottom plate 111 with bolts, and the pressure plate 13 corresponding to the left side plate 113 and right side plate 114 can be precisely fitted into the clearance area of ​​the support frame 14. Then, the top plate 112 is connected to the left side plate 113 and right side plate 114 with bolts, and the pressure plate 13 corresponding to the top plate 112 can be precisely fitted into the clearance area of ​​the support frame 14. Finally, the strain adjustment system 4 is set up in front of the observation window 119 to complete the complete assembly process of the loading simulation box 1.

[0059] Furthermore, the strain adjustment system 4 can be electrically connected to multiple telescopic components 321 of the loading and unloading assembly 3 via the wiring harness 33, so that the strain adjustment system 4 can control the extension and retraction of the telescopic unit 32. The strain adjustment system 4 controls the telescopic components 321 of the multiple telescopic units 32 of the loading and unloading assembly 3 to slowly pressurize, so that the telescopic unit 32 can extend and press against the inner peripheral wall of the simulated tunnel 21, thereby completing the pre-contact of the support in the simulated tunnel 21. The strain adjustment system 4 is also electrically connected to the pressurizing component 12 of the loading simulation box 1, so that the strain adjustment system 4 can control the loading simulation box 1 to apply simulated pressure to the model body 2. At the same time, the strain adjustment system 4 can monitor the model body 2 in real time until the simulated pressure reaches the target pressure of the actual working tunnel.

[0060] Furthermore, the strain adjustment system 4 can control the multiple telescopic units 32 of the loading and unloading component 3 to contract sequentially along the axial direction of the simulated tunnel 21, so as to gradually remove the support on the inner wall of the simulated tunnel 21 along the axial direction, thereby simulating the excavation and unloading process of the tunnel 21. At the same time, the strain adjustment system 4 can also monitor the model body 2 in real time during the excavation and unloading process of the simulated tunnel 21, so that the strain adjustment system 4 can obtain the deformation characteristics and stress evolution law during the tunnel excavation and unloading process based on the feedback data.

[0061] Thus, by controlling the sequential contraction of the telescopic unit 32 in the loading and unloading assembly 3, the excavation and unloading process of tunnel 21 can be simulated. The operation is convenient and can meet the requirements for accurate simulation of the excavation and unloading process of tunnels under various geological conditions, ensuring the scientific nature and accuracy of tunnel excavation model tests, and thus ensuring the safety of tunnel construction and the stability of long-term service.

[0062] According to the experimental method for simulating the unloading and tunneling process of a tunnel according to an embodiment of the present invention, the model body 2 is pressurized by loading simulation box 1 to simulate actual working conditions. An loading and unloading component 3 is set in the simulated tunnel 21. Multiple telescopic units 32 of the loading and unloading component 3 can be contracted sequentially to separate from the inner peripheral wall of the simulated tunnel 21, thereby accurately simulating the dynamic unloading characteristics during the tunnel excavation process. At the same time, the strain adjustment system 4 can detect the stress change of the model body 2 during the sequential contraction of multiple telescopic units 32, thereby ensuring the reliability of the test data measured by the test device, ensuring the safety of tunnel construction and the stability of long-term service, with better performance and wider applicability.

[0063] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0064] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A test apparatus for simulating the unloading and tunneling process of tunnel excavation, characterized in that, include: Load the simulation box (1); Model body (2), the model body (2) is installed in the loading simulation box (1), the loading simulation box (1) is used to pressurize the model body (2), and a simulated tunnel (21) is formed in the model body (2). Loading and unloading assembly (3), which is installed in the simulated tunnel (21), includes multiple telescopic units (32), which are distributed sequentially along the axial direction of the loading and unloading assembly (3) and are radially retractable. The multiple telescopic units (32) are adapted to be inserted into the simulated tunnel (21) and extend to press against the inner peripheral wall of the simulated tunnel (21), and the multiple telescopic units (32) are adapted to retract sequentially to separate from the inner peripheral wall of the simulated tunnel (21). The strain adjustment system (4) is used to adjust the loading pressure of the loading simulation box (1) according to the actual working conditions, and to detect the stress change of the model body (2) during the sequential contraction of the multiple expansion units (32).

2. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 1, characterized in that, The telescopic unit (32) includes multiple telescopic components (321) and multiple support plates. The multiple telescopic components (321) are distributed circumferentially along the loading and unloading assembly (3). The multiple telescopic components (321) and the multiple support plates are arranged in a one-to-one correspondence. Each support plate is installed at one end of the corresponding telescopic component (321). The telescopic component (321) is used to drive the support plate to move radially.

3. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 2, characterized in that, The plurality of support plates include a plurality of type I plates (322) and a plurality of type II plates (323). The type I plate (322) is constructed as a fan-shaped ring with an outer ring central angle smaller than the inner ring central angle, and the type II plate (323) is constructed as a fan-shaped ring with an outer ring central angle larger than the inner ring central angle. The plurality of type I plates (322) and the plurality of type II plates (323) are staggered in sequence along the circumferential direction. The first type plate (322) is adapted to radially contract before the second type plate (323), and the second type plate (323) is adapted to radially extend before the first type plate (322).

4. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 2, characterized in that, The loading and unloading assembly (3) also includes a mounting post (31), a plurality of telescopic units (32) are axially distributed on the outer peripheral wall of the mounting post (31), and the other end of the plurality of telescopic members (321) is connected to the mounting post (31); The mounting column (31) is coaxially arranged with the simulated tunnel (21).

5. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 1, characterized in that, The loading simulation box (1) includes a box body and multiple pressurizing components (12). The box body is located outside the loading simulation box (1), and the multiple pressurizing components (12) are arranged around the inner wall of the box body. The multiple pressurizing components (12) are used to pressurize the model body (2).

6. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 5, characterized in that, The loading simulation box (1) also includes four pressure plates (13). The four pressure plates (13) are installed in the box and are respectively arranged corresponding to the inner bottom wall, inner top wall, left inner side wall and right inner side wall of the box. One end of the pressure member (12) is connected to the box and the other end is connected to the pressure plate (13). The pressure member (12) is adapted to drive the pressure plate (13) to press against the model body (2).

7. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 6, characterized in that, The loading simulation box (1) also includes a support frame (14), which is installed inside the box and supported between the box and the model body (2). The support frame (14) forms a clearance area, and the pressure plate (13) is adapted to move through the clearance area to press against the model body (2).

8. The experimental apparatus for simulating tunnel excavation and unloading process according to claim 7, characterized in that, The front of the support frame (14) is constructed as an observation window (119), and the strain adjustment system (4) is adapted to detect stress changes in the model body (2) through the observation window (119).

9. The experimental apparatus for simulating the tunnel excavation and unloading process according to claim 7, characterized in that, The rear side of the support frame (14) is a mounting plate (120), and the loading and unloading assembly (3) is detachably mounted on the mounting plate (120) at one end along the axial direction. And / or, the outer peripheral wall of the housing is formed with a first reinforcing member (118).

10. A test method for simulating the unloading and tunneling process of tunnel excavation, characterized in that, The test apparatus (100) applicable to the simulated tunnel excavation and unloading process according to any one of claims 1-9, the test method comprising: The multiple telescopic units (32) of the loading and unloading assembly (3) are controlled to extend and press against the inner peripheral wall of the simulated tunnel (21); The loading simulation box (1) is controlled to apply simulated pressure to the model body (2), and the simulated pressure reaches the target pressure of the actual working tunnel. The multiple telescopic units (32) of the loading and unloading assembly (3) are controlled to retract sequentially to gradually remove the support for the inner peripheral wall of the simulated tunnel (21) along the axial direction; The stress changes of the model body (2) are obtained during the sequential contraction of the multiple expansion units (32), and the stress changes are analyzed.

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