Experimental device for simulating surface load and foundation settlement

Abstract

The invention relates to the technical field of geological simulation, and discloses an experimental device for simulating surface load and foundation settlement, which comprises a frame main body, a model box, a loading plate, a loading assembly, a movable door assembly and a pipeline, the frame body is fixed to the ground, the model box is installed in the frame body and filled with simulation media, the loading plate is arranged at the top of the model box in an up-down sliding mode, the loading assembly is installed at the top of the frame body and used for applying downward pressure to the loading plate, and the movable door assembly forms the bottom of the model box. The movable door assembly comprises a plurality of movable doors which are sequentially and adjacently arranged, any movable door is connected with the frame main body in an up-down sliding manner, the pipeline is horizontally fixed in the model box, the length direction of the pipeline is parallel to the arrangement direction of the movable doors, and the pipeline is fixed between the loading plate and the movable door assembly; various simulation tests are realized for the buried pipeline by using one experimental device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of geological simulation, and particularly relates to an experimental device for simulating surface load and foundation settlement. BACKGROUND

[0002] Buried pipelines are key lifelines in urban infrastructure, responsible for transporting public utility resources such as water and gas under roads and developed land.

[0003] Urban traffic roads are complex, and development and construction are often carried out in urban areas. Traffic and operation scenes inevitably intersect with buried pipelines. The buried pipelines at the intersection are often subjected to periodic loads from the ground (such as traffic loads) and external static loads (such as surrounding excavation and construction loads), thereby generating static and dynamic stresses in the pipeline structure and the surrounding soil.

[0004] In recent years, researchers have explored various protection methods for buried pipelines, including laying rubber sand mixture, foam lightweight soil, geogrid and recycled aggregate above the pipeline to reduce external loads and improve the anti-deformation capacity of the structure. In order to observe the surface settlement and pipeline response when using protective materials under the action of loads, researchers tend to use simulation devices for testing.

[0005] Existing simulation devices are mostly used for soil arch research and cannot bury pipelines, making it difficult to evaluate pipeline responses under complex foundation deformation and surface load. Most simulation devices are single-function type and lack a flexible switching combination system, which cannot realize integrated testing of progressive failure and surface load application in the same test framework. This functional separation leads to repeated investment in equipment, experimental space and operating resources.

[0006] Therefore, how to develop a comprehensive experimental device for multiple simulation tests of buried pipelines has become a technical problem to be solved. SUMMARY

[0007] The technical problem to be solved by the present application is how to develop a comprehensive experimental device for multiple simulation tests of buried pipelines.

[0008] In order to solve the above technical problems, the present application provides an experimental device for simulating ground load and foundation settlement, comprising: a frame body fixed on the ground; a model box installed in the inside of the frame body, the model box is filled with simulation medium; a loading plate slidingly arranged on the top of the model box; a loading assembly installed on the top of the frame body, used for applying downward pressure to the loading plate; a movable door assembly constituting the bottom of the model box, the movable door assembly comprises a plurality of movable doors arranged in sequence, any movable door is slidingly connected with the frame body; a pipeline horizontally buried in the simulation medium, the length direction of the pipeline is parallel to the arrangement direction of the plurality of movable doors, and the pipeline is located between the loading plate and the movable door assembly.

[0009] In an embodiment, the experimental device further comprises two plugboards, the two plugboards are distributed on both sides of the pipeline, and the two plugboards abut against the side wall of the model box, the length of the two plugboards is greater than the length of the movable door assembly, and the two plugboards are used for adjusting the available width of the movable door assembly.

[0010] In an embodiment, at least one plugboard is made of transparent material, and a first visual window is formed in the side wall close to the transparent plugboard.

[0011] In an embodiment, a second visual window is formed in the side wall of the model box perpendicular to the pipeline, and the second visual window is located at a position corresponding to the fixed position of the pipeline.

[0012] In an embodiment, a horizontal slide rail is arranged on the frame body, the model box is slidingly connected with the horizontal slide rail, one end of the horizontal slide rail close to the loading assembly is a loading position, the other end of the horizontal slide rail is a loading and unloading position, and the model box is further used for reciprocating sliding between the loading position and the loading and unloading position.

[0013] In an embodiment, a sand discharging hole is formed in the side of the model box, a sand discharging plate covers the sand discharging hole, the sand discharging plate is detachably connected with the model box, and a sand discharging interface is further arranged on the frame body, the sand discharging hole is aligned with the sand discharging interface when the model box slides to the loading and unloading position.

[0014] In an embodiment, the horizontal slide rail comprises a plurality of rollers arranged at intervals, and the model box rolls on the rollers.

[0015] In an embodiment, the loading assembly is an electric cylinder, the maximum loading capacity of the electric cylinder is 20kN, and the dynamic load frequency range of the electric cylinder is 0-1Hz.

[0016] In an embodiment, the movable door assembly comprises five movable doors, the long side of any movable door is 300mm, the short side of any movable door is 150mm, the long side of any movable door is used as the width of the movable door assembly, and the sum of the short sides of the five movable doors is used as the length of the movable door assembly.

[0017] In an embodiment, the experimental device further comprises at least one of the following sensors: an LVDT displacement sensor, which is placed inside the pipe, for measuring the displacement of the pipe in any direction during loading; a strain sensor, which is laid on the pipe, for providing strain data required to calculate the bending moment of the pipe; a pressure sensor, which is arranged in the simulated medium surrounding the pipe.

[0018] Compared with the prior art, the experimental device for simulating ground load and foundation settlement has the following beneficial effects:

[0019] In the experimental device, the upper loading assembly can push the loading plate from top to bottom, and then compress the simulated medium downward, thereby realizing the experimental function of simulating ground load. The plurality of movable doors are arranged adjacent to each other, and each movable door is independently slidable upward and downward, so that complex foundation deformation such as local voiding, soil arching effect and progressive failure can be simulated. Similarly, using one movable door or multiple movable doors to move downward synchronously and slowly can simulate ground subsidence, and when the movable door moves downward quickly, soil collapse can be simulated. Since the pipe is arranged in the model box and located between the loading plate and the movable door assembly, the effects of various loads and geological changes on the buried pipe can be intuitively and accurately evaluated, and multiple simulation tests for the buried pipe can be realized by using one experimental device. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a perspective view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0021] Figure 2 is a front view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0022] Figure 3 is a right view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0023] Figure 4 is a front view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0024] Figure 5 is a top view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0025] Figure 6 is a front view of an experimental device for simulating ground load and foundation settlement according to an embodiment of the present application.

[0026] Figure 7 is a connection diagram of a data acquisition instrument and a LVDT displacement sensor of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0027] Figure 8 is a layout diagram of a strain sensor on a pipeline of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0028] Figure 9 is a layout diagram of a pressure sensor on a pipeline of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0029] Figure 10 is a right view diagram of a pipeline of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0030] Figure 11 is a top view diagram of a model box of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0031] Figure 12 is a sectional view diagram of a model box of an experimental device for simulating ground surface load and foundation settlement exemplarily shown by an embodiment of the present application.

[0032] Reference signs:

[0033] 1, model box, 2, loading assembly, 3, movable door assembly, 4, loading plate, 5, plug-in plate, 6, sand unloading plate, 7, sand unloading interface, 8, horizontal slide rail, 9, frame main body, 10, pipeline, 11, first visual window, 12, movable door power device, 13, second visual window, 14, data acquisition instrument, 15, LVDT displacement sensor, 16, strain sensor, 17, pressure sensor. DETAILED DESCRIPTION

[0034] The specific embodiments of the present application are described in further detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0035] In the description of the present application, it should be understood that the term "assembly" is used in the present application only to represent the containing relationship of the device, and is not used to limit the structural form of the device in the present application. The terms such as "sand discharge hole", "sand discharge plate" and "sand discharge interface" are only named for the commonly used medium, but not used to limit the used simulation medium. The terms such as "first", "second" are intended to distinguish similar objects, and are not used to describe a specific structure. It should be understood that under appropriate circumstances, such terms can be interchangeable, so that the embodiments of the present application can be implemented in structures other than those shown or described. In addition, "include", "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a product or device including a series of components or units need not be limited to only those components or units explicitly listed, but can also include other components or units not explicitly listed but inherent to such products or devices.

[0036] Buried pipelines are key lifelines in urban infrastructure, responsible for transporting water, gas and other public utility resources under roads and developed land.

[0037] Urban traffic roads are complex, and development and construction are often carried out in urban areas. Traffic and operation scenarios will inevitably intersect with buried pipelines. The buried pipelines at the intersection are often subjected to periodic loads from the ground surface (such as traffic loads) and external static loads (such as surrounding excavation and construction loads), thereby generating static and dynamic stresses in the pipeline structure and the surrounding soil.

[0038] In recent years, researchers have explored various protection methods for buried pipelines, including laying rubber sand mixture, foam lightweight soil, geogrid and recycled aggregate above the pipeline to reduce external loads and improve the anti-deformation capacity of the structure. In order to observe the ground settlement and pipeline response when using protective materials under load, researchers tend to use simulation devices for testing.

[0039] Existing simulation devices are mostly used for soil arch research and cannot be used to bury pipelines, making it difficult to evaluate pipeline response under complex ground deformation and ground load. Moreover, most simulation devices are single-function type and lack a flexible switching combination system, which cannot realize integrated testing of progressive failure and ground load application in the same test framework. This functional separation leads to repeated investment in equipment, experimental space and operating resources.

[0040] To solve this problem, as shown in Figure 1 , Figure 5 and Figure 6 , the preferred embodiment of the embodiment of the present application is an experimental device for simulating ground load and ground settlement, which comprises: a frame body 9, a model box 1, a loading plate 4, a loading assembly 2, a movable door assembly 3 and a pipeline 10.

[0041] The frame body 9 is fixed on the ground, the model box 1 is installed in the inside of the frame body 9, the model box 1 is filled with simulation medium, the loading plate 4 is slidably arranged on the top of the model box 1, the loading assembly 2 is installed on the top of the frame body 9, and the loading assembly 2 is used for applying downward pressure to the loading plate 4, the movable door assembly 3 is composed of the bottom of the model box 1, the movable door assembly 3 comprises a plurality of movable doors arranged in sequence, any movable door is slidably connected with the frame body 9 in the up-down direction, the pipeline 10 is horizontally buried in the simulation medium, the length direction of the pipeline 10 is parallel to the arrangement direction of the plurality of movable doors, and the pipeline 10 is located between the loading plate 4 and the movable door assembly 3.

[0042] The loading assembly 2 located above the model box 1 can push the loading plate 4 from top to bottom, thereby applying pressure to the simulation medium, and the experimental function of simulating the ground surface load is realized.

[0043] The plurality of movable doors are arranged in sequence, and each movable door is independently slidable in the up-down direction, so that complex foundation deformation such as local voiding, soil arching effect and progressive failure can be simulated.

[0044] For example, when part of the movable doors are static and part of the movable doors are sunken, the mechanical environment of 'uneven support' in the process of local voiding of the foundation can be simulated, and the stress transfer path formed by the particle redistribution of the simulation medium can be directly observed;

[0045] By adjusting the differential settlement rate of the movable doors (for example, slow in the middle and fast on both sides), the dynamic process of 'arch formation-stress transfer to arch foot-stress release in arch' in the soil arching effect can be reproduced, and visual experimental basis is provided for the soil arching mechanism research.

[0046] For progressive failure, by controlling the slow and stepped sinking of the movable doors, the damage accumulation process of the simulation medium from local crack initiation to overall instability can be accurately captured, and the defect that the traditional device is difficult to simulate 'time effect' is overcome.

[0047] The experimental device integrates the functions of 'ground surface load simulation', 'foundation deformation simulation' and'response evaluation of the buried pipeline 10' in one, and multiple scene experiments can be completed without replacing the equipment, so that the experimental efficiency is greatly improved:

[0048] The loading assembly 2 can simulate different types of ground surface loads such as static load (such as peripheral excavation and construction load) and dynamic cyclic load (such as traffic load) by adjusting the pressure size and loading rate, and the influence law of load characteristics on foundation deformation can be studied;

[0049] The'slow motion-fast motion' mode switching of the movable doors can seamlessly link the simulation of 'ground subsidence' and'soil collapse': the slow motion simulates the long-term and slow subsidence process, the fast motion simulates the sudden and local collapse and damage, and the differential effects of the two phenomena on the pipeline 10 are compared;

[0050] The built-in pipeline 10 design makes the experiment always revolve around the "foundation-pipeline 10" interaction, avoids the disconnection problem of traditional "separate measurement of foundation" and "separate measurement of pipeline 10", and more truly reflects the stress, deformation and damage characteristics of the pipeline 10 under the combined geological action in engineering.

[0051] It can be understood that the simulation medium in the application can be one of the following materials or a composite of multiple materials: rubber sand mixture, sand, soil, geogrid, foam lightweight soil, recycled aggregate, elastomer composite material, polyurethane foam, elastomer composite geotechnical net, nano-enhanced soil, variable density medium, intelligent response material and geotextile.

[0052] In order to adapt to different experimental requirements, the application does not limit the specific simulation medium, so any simulation medium provided by the application or other medium not listed falls within the protection scope of the application when it does not affect the implementation of the application.

[0053] In an embodiment, as shown in the perspective view of Figure 1 and the top view of Figure 3 , the experimental device can further include two insertion plates 5, which are distributed on both sides of the pipeline 10 and abut against the side walls of the model box 1. The lengths of the two insertion plates 5 are both greater than the length of the movable door assembly 3, and the two insertion plates 5 are used to adjust the available width of the movable door assembly 3.

[0054] The available width (such as 300mm or 600mm) of the movable door assembly 3 can be adjusted by the insertion plate 5, that is, the action range of the simulation medium is adjusted, and different specifications of simulation experiments can be performed.

[0055] For example, when simulating the uneven foundation settlement condition, the insertion plate 5 does not need to be installed, and the full-width area of the model box 1 is used for test operation; when simulating the uniform foundation settlement condition, the insertion plate 5 can be installed to limit the effective width, and the uniform settlement and uneven settlement conditions can be flexibly simulated.

[0056] It can be understood that, in order to make the control of the movable door assembly 3 effective, the length of the pipeline 10 in the application is greater than the length of the movable door assembly 3, so that each movable door can correspond to a region of the same size on the pipeline 10, and the stress difference between the end and other positions of the pipeline 10 is reduced. The influence on the experimental results.

[0057] For the same reason, the length of the insertion plate 5 is also greater than the length of the movable door assembly 3, so that each movable door is within the coverage range of the insertion plate 5, and the effective width of each movable door can be adjusted by the insertion plate 5.

[0058] An exemplary structure of the insertion plate 5 is shown in Figure 4As shown, a plurality of beam column structures can be arranged to strengthen, and the middle part can be made of transparent material to facilitate observation.

[0059] It can be understood that in the simulation experiment, observation can be performed in various ways, such as built-in camera, and data acquisition can also be performed through sensors. In the present application, in order to intuitively observe the experimental process and understand the relationship between the experimental data and the experimental process, the process of the simulation experiment can be observed by naked eye.

[0060] As shown in an embodiment, at least one plugboard 5 is made of transparent material, and a first visual window 11 is arranged on the side wall close to the transparent plugboard 5. Figure 2

[0061] By using transparent material as the plugboard 5, the visualization of the plugboard 5 is realized, and the movement of the simulation medium can be directly observed from the outside through the first visual window 11, so as to intuitively observe the experimental process.

[0062] It can be understood that the present application does not make specific limitations on the transparent material, and specific transparent materials such as acrylic, PC (Polycarbonate) or other transparent materials with certain mechanical properties can be used.

[0063] Furthermore, in order to realize visualization from more angles and observe the state of another view of the pipeline 10, a second visual window 13 is arranged on the side wall of the model box 1 perpendicular to the pipeline 10, and the arrangement position of the second visual window 13 corresponds to the fixed position of the pipeline 10. The second visual window 13 on the side of the model box 1 is used to observe the deformation of the pipeline 10 and the simulation medium around the pipeline 10 in the experimental process from the axial direction of the pipeline 10.

[0064] The first visual window 11 and the second visual window 13 can be arranged in a way that the opening is first and then the transparent material is used for sealing, so as to realize visualization without affecting the simulation experiment.

[0065] In an embodiment, a horizontal sliding rail 8 is arranged on the frame body 9, the model box 1 is slidingly connected with the horizontal sliding rail 8, one end of the horizontal sliding rail 8 close to the loading assembly 2 is a loading position, the other end of the horizontal sliding rail 8 is a loading and unloading position, and the model box 1 is further used for reciprocating sliding between the loading position and the loading and unloading position.

[0066] Since the experimental device needs a large loading force, more beam column structures are added to the frame body 9 to ensure the structural strength, and these reinforced structures make it difficult to fill the simulation medium in the model box 1 located in the frame body 9.

[0067] ​And through the horizontal slide rail 8, the model box 1 is allowed to reciprocate between the loading position (for load test) and the loading and unloading position (for unloading or adjusting position), which can avoid these reinforced structures, and realize quick loading and replacement of simulation medium.

[0068] In the application, the design of the horizontal slide rail 8 can combine high friction-resistant materials (such as PC polycarbonate) or lubrication systems to ensure the stability and reliability of the model box 1 during sliding, and avoid experimental errors caused by poor sliding.

[0069] In the previous embodiment, when the model box 1 slides to the loading and unloading position, the simulation medium can be poured or taken out directly from the opening in the upper part, although the interference of the frame body 9 is avoided, but the efficiency is low.

[0070] In order to further improve the efficiency, on the basis of the above embodiment, as shown in the figure, Figure 1 The side of the model box 1 can be provided with a sand discharging hole, and a sand discharging plate 6 covers the sand discharging hole, the sand discharging plate 6 is detachably connected with the model box 1, and the frame body 9 is also provided with a sand discharging interface 7, and when the model box 1 slides to the loading and unloading position, the sand discharging hole is aligned with the sand discharging interface 7.

[0071] By setting a special sand discharging structure and sand discharging hole, removing the sand discharging plate 6, the simulation medium can be quickly taken out by gravity, and the simulation medium can be introduced into other containers through the sand discharging interface 7 for easy storage.

[0072] The horizontal slide rail 8 can adopt any structure, such as a linear guide rail, an optical axis or other structures that can slide along a straight line.

[0073] In an embodiment of the application, the horizontal slide rail 8 can include a plurality of rollers arranged at intervals, and the model box 1 rolls on the rollers.

[0074] The main demand point of the application is to bear weight and move between two positions, and the precision requirement is low, the roller is used as the horizontal slide rail 8, the load is high, the assembly precision requirement is low, the demand of bearing and low precision straight line movement in the application can be met, the cost can be appropriately reduced, the maintenance requirement is low, and the durability is stronger.

[0075] In an embodiment, the loading assembly 2 is an electric cylinder, the maximum loading capacity of the electric cylinder is 20kN, and the dynamic load frequency range of the electric cylinder is 0-1Hz. The electric cylinder supports constant pressure loading, constant tension loading, and can also be speed controlled and displacement controlled, and has multiple loading modes to adapt to different test requirements.

[0076] Due to the 0-1Hz dynamic control of the electric cylinder, a plurality of power devices are not needed, and a set of electric cylinder can meet the requirements of various experiments.

[0077] In addition, as shown in the figure,Figure 2 and Figure 3 As shown in the figure, each movable door is equipped with a movable door power device 12, and each movable door power device 12 can independently control whether to move, movement speed and movement displacement.

[0078] By equipping each movable door with an independent power device, precise control of the movement state of the movable door is achieved, significantly improving the flexibility and refinement level of the application in simulating the uneven settlement of the municipal underground pipeline 10 foundation. It can simulate differential settlement for specific pipeline 10 areas (such as construction disturbance areas or traffic load areas), effectively avoid test distortion caused by traditional synchronous movement, and more accurately quantify the damage risk of local settlement to the pipeline 10, providing quantifiable high-precision data support for urban underground pipeline safety evaluation.

[0079] As shown in the figure, Figure 11 In an embodiment, the movable door assembly 3 includes five movable doors, the long side of any movable door is 300 mm, the short side of any movable door is 150 mm, the long side of any movable door serves as the width of the movable door assembly 3, and the sum of the short sides of the five movable doors serves as the length of the movable door assembly 3.

[0080] This embodiment optimizes the geometric size of the movable door assembly 3 (width 300 mm, length 750 mm) to achieve high-precision simulation in a small model test space: the short side (150 mm) of each movable door serves as an independent settlement unit, which can apply differential settlement displacement to specific areas, effectively avoiding test distortion caused by uneven settlement distribution in traditional single movable door devices, thereby significantly improving the safety evaluation accuracy of urban underground pipelines 10 under foundation settlement conditions, and providing more reliable damage risk quantification basis for engineering practice.

[0081] As shown in the figure, Figure 12 To match it, the length, width and height of the optional model box 1 in the application are 1200 mm, 600 mm and 1000 mm.

[0082] In an embodiment, the experimental device further comprises at least one of the following sensors:

[0083] As shown in the figure, Figure 7 LVDT (Linear Variable Differential Transformer) displacement sensor 15, LVDT displacement sensor 15 is placed inside the pipeline 10, used to measure the displacement of the pipeline 10 in any direction during loading.

[0084] As shown in the figure, Figure 8 Strain sensor 16, strain sensor 16 is laid on the pipeline 10, used to provide strain data required to calculate the bending moment of the pipeline 10.

[0085] As Figure 9 and Figure 10 The pressure sensor 17 is arranged in the simulated medium around the pipeline 10.

[0086] By integrating the LVDT displacement sensor 15 for monitoring the displacement of the pipeline 10, the strain sensor 16 for providing strain data to calculate the bending moment, and the pressure sensor 17 arranged in the simulated medium to measure the ground pressure, the multi-physical field coupling analysis capability of the present application in the test of the underground pipeline 10 is significantly improved, the displacement, bending stress and ground pressure distribution of the pipeline 10 under dynamic load can be quantified comprehensively, the monitoring blind area caused by traditional single sensor is effectively avoided, and high-precision damage risk quantification basis is provided for safety evaluation of urban underground pipeline.

[0087] The LVDT directly monitors the small displacement change inside the pipeline 10, avoiding external interference; the strain sensor 16 focuses on the mechanical deformation of the surface of the pipeline 10, providing raw data for bending moment calculation; the pressure sensor 17 independently senses the pressure distribution of the ground medium, thereby completely separating and quantifying the interaction between the displacement, internal strain and external ground pressure of the pipeline 10, avoiding signal confusion or measurement blind area caused by co-location of sensors, and ensuring that the test results can truly reflect the safety state of the urban underground pipeline under dynamic load.

[0088] As Figure 7 The experimental device in the present application can also include a data acquisition instrument 14, which is used to collect any sensor, and through real-time synchronous processing of multi-source sensor data, realizes accurate monitoring of the dynamic response of the displacement, strain and ground pressure of the pipeline 10, and effectively improves the evaluation reliability of the municipal underground pipeline 10 ground settlement test.

[0089] The above is only the preferred embodiment of the present application, it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and substitutions can be made, these improvements and substitutions should also be considered as the protection scope of the present application.

Claims

1. An experimental apparatus for simulating a ground surface load and a ground settlement, characterized by, The utility model relates to a kind of experimental device for simulating sand production in oil and gas reservoirs, comprising: Frame body (9), which is fixed on the ground; Model box (1), which is installed inside the frame body (9), filled with simulation medium inside the model box (1); Loading plate (4), which is arranged on the top of the model box (1) and slides up and down; Loading assembly (2), which is installed on the top of the frame body (9) and is used to apply downward pressure to the loading plate (4); Movable door assembly (3), which constitutes the bottom of the model box (1), comprises a plurality of movable doors arranged in sequence and adjacent to each other, and any movable door is connected to the frame body (9) in a sliding manner; Pipeline (10), which is horizontally buried in the simulation medium, the length direction of the pipeline (10) is parallel to the arrangement direction of the plurality of movable doors, and the pipeline (10) is located between the loading plate (4) and the movable door assembly (3).

2. The experimental setup of claim 1, wherein, The experimental device further comprises two plug-in plates (5), which are distributed on both sides of the pipeline (10) and abut against the side walls of the model box (1), and the lengths of the two plug-in plates (5) are greater than the length of the movable door assembly (3). The two plug-in plates (5) are used to adjust the available width of the movable door assembly (3).

3. The experimental set-up of claim 2, wherein, At least one of the plug-in plates (5) is made of transparent material, and a first visual window (11) is formed in the side wall close to the transparent plug-in plate (5).

4. The experimental setup of claim 1, wherein, A second visual window (13) is formed in the side wall of the model box (1) perpendicular to the pipeline (10), and the position of the second visual window (13) corresponds to the fixed position of the pipeline (10).

5. The experimental setup of claim 1, wherein, A horizontal sliding rail (8) is arranged on the frame body (9), the model box (1) is connected to the horizontal sliding rail (8) in a sliding manner, one end of the horizontal sliding rail (8) close to the loading assembly (2) is a loading position, the other end of the horizontal sliding rail (8) is a loading and unloading position, and the model box (1) is further used to reciprocate between the loading position and the loading and unloading position.

6. The experimental setup of claim 5, wherein, A sand discharging hole is formed in the side of the model box (1), a sand discharging plate (6) covers the sand discharging hole, the sand discharging plate (6) is detachably connected to the model box (1), a sand discharging interface (7) is further arranged on the frame body (9), and when the model box (1) slides to the loading and unloading position, the sand discharging hole is aligned with the sand discharging interface (7).

7. The experimental setup of claim 5, wherein, The horizontal sliding rail (8) comprises a plurality of rollers arranged at intervals, and the model box (1) rolls on the rollers.

8. The experimental setup of claim 1, wherein, The loading assembly (2) is an electric cylinder, the maximum loading capacity of the electric cylinder is 20kN, and the dynamic loading frequency range of the electric cylinder is 0-1Hz.

9. The experimental setup of claim 1, wherein, The movable door assembly (3) comprises five movable doors, the long side of any movable door is 300mm, the short side of any movable door is 150mm, the long side of any movable door serves as the width of the movable door assembly (3), and the sum of the short sides of the five movable doors serves as the length of the movable door assembly (3).

10. The experimental setup of claim 1, wherein, The experimental set-up also comprises at least one sensor: - an LVDT displacement sensor (15) placed inside the pipe (10) for measuring the displacement of the pipe (10) along either direction during loading; - a strain sensor (16) laid on the pipe (10) for providing strain data necessary to calculate the bending moment of the pipe (10); - a pressure sensor (17) arranged in the simulated medium surrounding the pipe (10).

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