Test apparatus and test method for the coupled effect of foundation pit dewatering and excavation on adjacent pipelines

Abstract

This invention provides a test apparatus and method for studying the coupled effects of dewatering and excavation on adjacent pipelines in foundation pits. This addresses the limitations of existing technologies in studying the combined disturbance effects of dewatering and excavation on adjacent pipelines and in simulating the coupled disturbance mechanisms between adjacent foundation pits. The apparatus includes: a base, simulated pipelines, a dewatering simulation mechanism, and an excavation simulation mechanism. The simulated pipelines include a first pipeline and a second pipeline, with multiple first pipelines and / or multiple second pipelines within an annular groove. The dewatering simulation mechanism includes a hydraulic simulation component and a monitoring component. The excavation simulation mechanism includes a suspension component and at least two excavation components. The suspension component is positioned above the base and drives the excavation components to rotate around the axis of the annular groove, thereby changing the spacing between the excavation components. This apparatus can simulate both the combined effects of dewatering and excavation on adjacent pipelines and the coupled disturbance mechanisms between adjacent foundation pits.

Description

Technical Field

[0001] This invention belongs to the field of building engineering technology, and in particular relates to a test device and test method for the coupling effect of foundation pit dewatering excavation on adjacent pipelines. Background Technology

[0002] In recent years, as my country's urbanization has entered a stage of high-quality renewal and development, urban surface infrastructure has become increasingly sophisticated, and surface land resources are approaching saturation. Urban development and construction models have gradually shifted from traditional large-scale above-ground construction to in-depth expansion into underground space. As a core public welfare project in urban underground space development, subway engineering has seen continuous improvement in its construction scale, coverage, and construction depth. Simultaneously, the underground pipe network system in urban core areas is dense and complex, with various pipelines and ancillary facilities such as water supply, drainage, gas, heating, electricity, communications, and broadcasting widely distributed, constituting a core "lifeline" project that maintains the normal operation of the city and ensures the production and lives of residents. These pipelines are characterized by dense layout, complex ownership, varying burial depths, diverse pipe diameters, and significant material differences, making the situation of deep foundation pit construction for subways adjacent to and intersecting with existing underground pipelines a common occurrence in the industry.

[0003] However, existing research and supporting experimental equipment still have significant technical shortcomings, making it difficult to adapt to the complex construction scenarios of urban cluster foundation pits and the comparative research needs of multiple types of pipelines. Existing research mostly focuses on simulating single foundation pit excavation or single dewatering conditions, failing to study the superimposed disturbance effect of the coupled synergistic effect of simulated dewatering and excavation on adjacent pipelines. The research conditions deviate from actual construction conditions, leading to incomplete mechanism analysis. Furthermore, existing experimental equipment has limited functionality, only capable of simulating independent excavation of a single foundation pit, unable to reproduce the cluster construction conditions commonly found in urban engineering, such as simultaneous excavation of multiple foundation pits or staggered excavation in stages. It is difficult to simulate the coupled superimposed disturbance mechanism between adjacent foundation pits, and it is impossible to conduct multivariate comparative experiments with different foundation pit spacing, excavation sequence, and excavation rate. It cannot systematically reveal the impact mechanism of cluster foundation pit construction on ground settlement and pipeline deformation. The theoretical research system is incomplete, and the experimental results have poor authenticity and engineering adaptability.

[0004] Furthermore, the layout of urban underground pipelines is complex, with pipelines of different diameters, burial depths, materials, and arrangements coexisting on the same construction site. The response mechanisms of these pipelines to dewatering and excavation disturbances vary significantly. Existing testing equipment cannot perform simultaneous, controlled tests on multiple types of pipelines in a single space. Under uniform testing conditions, it is difficult to accurately compare and analyze the influence of key parameters such as pipe diameter, burial depth, material, and arrangement on the pipeline's deformation response to dewatering, and thus cannot accurately reveal the differentiated deformation mechanisms of different types of pipelines. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a test device and test method for the coupling effect of foundation pit dewatering and excavation on adjacent pipelines, so as to solve the problems in the prior art that cannot study the superimposed disturbance effect of the coupled effect of dewatering and excavation on adjacent pipelines and cannot simulate the coupling superimposed disturbance mechanism between adjacent foundation pits.

[0006] To achieve the above and other related objectives, the present invention provides a test apparatus for coupling the dewatering excavation of a foundation pit with the action of adjacent pipelines, comprising: The base has a downwardly recessed annular groove on its top surface; The simulated pipeline includes a first pipeline and a second pipeline, and the annular groove has a plurality of the first pipelines and / or a plurality of the second pipelines; A precipitation simulation mechanism, comprising a hydraulic simulation component and a monitoring component, wherein the hydraulic simulation component has a first state and a second state, wherein the hydraulic simulation component is configured to allow water to flow into the annular groove in the first state to establish an initial water level, and to pump water from a simulated pit in the annular groove in the second state. The monitoring component is configured to acquire the internal state parameters of the annular groove in real time during the test. An excavation simulation mechanism includes a suspension assembly and at least two excavation assemblies. The suspension assembly is configured above the base to drive the excavation assemblies to perform circular motion around the axis of the annular groove, thereby changing the spacing between the excavation assemblies. The excavation assembly includes a fixed arm, a vertical power unit, and an excavation part. The fixed arm is fixedly connected to the suspension assembly, and the vertical power unit is configured on the fixed arm to drive the excavation part to move in the vertical direction.

[0007] Optionally, the plurality of first pipelines are pipes and / or cables, and the plurality of second pipelines are pipes and / or cables; Multiple first pipelines within the same horizontal plane are arranged collinearly with and / or at an angle to the central axis of the annular groove, and multiple second pipelines within the same horizontal plane are arranged perpendicularly to and / or at an angle to the central axis of the annular groove.

[0008] Optionally, the multiple first pipelines are buried at the same and / or different depths, and the multiple second pipelines are buried at the same and / or different depths; And / or, multiple first pipelines are made of the same and / or different materials, and multiple second pipelines are made of the same and / or different materials; And / or, multiple first pipelines have the same and / or different diameters, and multiple second pipelines have the same and / or different diameters.

[0009] Optionally, it also includes at least two partition plates, which divide the annular groove into two simulated slots for placing simulated foundation pit soil. The excavation mechanism has at least four excavation components.

[0010] Optionally, the suspension assembly includes a suspension plate, a first track, a second track, an internal gear, an external gear, and a moving part; The suspension plate is ring-shaped, and the first track and the second track are located above the suspension plate. The central axis of the first track, the second track and the suspension plate are collinear. The internal gear and the external gear are coaxially fixed to the inner and outer sides of the suspension plate, respectively. The first track and the second track each have at least one moving part. The moving part is configured to mesh with the internal gear or the external gear to make circumferential movement along the first track or the second track, thereby driving the excavation component to change position. The number of excavation components is equal to the sum of the number of moving parts on the first track and the second track.

[0011] Optionally, the moving part includes a motion mounting base, a stabilizing roller, a drive gear, and a motion power source; The stabilizing roller has a groove on its side; The motion mounting base is located above the first track. Multiple stabilizing rollers are rotatably mounted on both sides of the bottom surface of the motion mounting base. The grooves on the stabilizing rollers on both sides are respectively in rolling cooperation with the inner and outer tracks of the first track, and the rolling axis is parallel to the central axis of the first track. The drive gear is rotatably connected to the motion mounting base. The motion power source of the moving part located on the first track drives the drive gear to rotate and meshes with the internal gear to make the moving part perform circular motion around the central axis of the internal gear. The motion power source of the moving part located on the second track drives the drive gear to rotate and meshes with the external gear to make the moving part perform circular motion around the central axis of the external gear.

[0012] Optionally, the excavation section includes a connecting arm, which is fixedly connected to the telescopic end of the vertical power section; A receiving cavity, the receiving cavity being fixedly connected to the connecting arm and having an internal space extending axially; A drive rod is rotatably connected to the receiving cavity. The top end of the drive rod extends out of the receiving cavity, and the bottom end is fixedly connected to an excavation unit. The drive rod forms a through space along its own axis for the dewatering well to pass through. The conveying screw is located from the middle to the bottom of the drive rod. The conveying screw contacts and engages with the inner surface of the receiving cavity to form a conveying channel for conveying soil from bottom to top along the axial direction. A storage area is formed between the top of the receiving cavity and the circumferential sidewall and the top of the conveying screw. The excavation power unit is used to drive the drive rod to rotate, so as to drive the excavation unit to excavate the simulated foundation pit soil.

[0013] Optionally, the excavation unit includes a first ring body, which is coaxially rotatably connected to the bottom end of the receiving cavity; The second ring body is coaxially disposed below the first ring body and is coaxially fixedly engaged with the bottom end of the drive rod; Multiple helical cutter arms are evenly spaced along the circumference of the first ring body. Each helical cutter arm is fixedly connected to the first ring body and the second ring body at both ends, and each helical cutter arm has a number of cutting teeth along its own helical direction.

[0014] Optionally, the hydraulic simulation component includes a water supply unit, a dewatering well, a dewatering pipe, and a first vertical pipe, wherein the number of the dewatering well, the dewatering pipe, and the simulation tank are equal; The dewatering well is located inside the simulated foundation pit, and the insertion end of the dewatering well has several water holes evenly arranged along its own axial and circumferential directions. One end of the dewatering pipe is located inside the dewatering well. Both the first vertical pipe and the dewatering pipe are equipped with water pumps and control valves. During the test, the other end of the dewatering pipe is connected to the second spiral pipe through a quick connector. The water supply unit is connected to the first vertical pipe to provide an initial water level for the simulation tank.

[0015] A test method for a test device that couples the effects of foundation pit dewatering and excavation with those of adjacent pipelines, applicable to the test device that couples the effects of foundation pit dewatering and excavation with those of adjacent pipelines, comprising the following steps: Soil laying steps: According to the test requirements, a cohesive relative water-impermeable layer and a sandy confined aquifer with a specified particle size are laid in the annular groove. According to the test plan, dewatering wells are buried at predetermined elevations and positions. The first pipeline and / or the second pipeline are buried at preset positions. The monitoring component is set in the annular groove, wherein the dewatering well is set at the center of the simulated foundation pit. Simulated foundation pit selection steps: Select the location of the simulated foundation pit and install a water-stop curtain at the edge of the foundation pit; Initial positioning steps for excavation: Place each of the excavation components at the preset center point of the simulated foundation pit, extend the vertical power unit, pass the dewatering well through the center of the excavation part, and as the excavation part moves downward, the dewatering well extends out of the top of the excavation part. One end of the dewatering pipe is located in the dewatering well, and the other end is connected to the second spiral pipe through a quick connector. Initial water level setting steps: When the hydraulic simulation component is in the first state, water is injected into the concave groove through the pre-reserved interconnected holes in each soil layer to apply a preset initial water head to the impermeable layer and the confined aquifer respectively. After static stabilization, the monitoring component collects the initial basic parameters in real time to complete the calibration of the initial test conditions. The water-induced excavation simulation steps are as follows: When the hydraulic simulation component is in the second state, water is first pumped out from the simulated foundation pit in the annular groove and left to stand for 30 minutes. Then, the vertical power unit is activated to drive the excavation unit to move downward to the predetermined excavation depth and stays for 30 minutes. Throughout the process, data is collected in real time through the monitoring component. The above process is repeated until the test ends.

[0016] As described above, the experimental apparatus and method for coupling the dewatering excavation of a foundation pit with the adjacent pipeline, according to the present invention, have at least the following beneficial effects: By linking and coordinating the dewatering simulation mechanism and the excavation simulation mechanism, simultaneous simulations of foundation pit dewatering and soil excavation can be conducted. This simulates the evolution of ground stress, water level, and settlement under the coupled effects of dual working conditions, as well as the superimposed disturbance deformation characteristics of adjacent underground pipelines. This allows for a comprehensive and realistic revelation of the disturbance mechanism of foundation pit construction on pipelines, thus improving the relevant theoretical research system. Through the configuration of at least two excavation components and the circular motion function driven by the suspension component, the spacing between the excavation components can be changed, enabling various cluster construction modes such as simultaneous excavation of multiple foundation pits and staggered excavation. This allows for the study of the coupling and superimposed disturbance mechanism between adjacent foundation pits. Furthermore, by independently driving each excavation component and precisely controlling the excavation rate and depth by the vertical power unit, multivariate comparative experiments can be conducted with different foundation pit spacings, excavation sequences, and excavation rates. This systematically reveals the impact mechanism of cluster foundation pit construction on ground settlement and pipeline deformation, significantly improving the engineering adaptability and realism of the experimental results. Through the design of at least two partition plates, simulated pipelines, dewatering simulation mechanism and excavation simulation mechanism, the first pipeline in the same plane is arranged collinearly / inclined along the central axis of the annular groove, and the second pipeline in the same plane is arranged perpendicular to the central axis / inclined. The two types of pipelines can be arranged separately in a single simulated trench, arranged differently in two trenches, or arranged in the same trench. This allows for the simulation of underground integrated pipe corridors, the reproduction of underground pipelines with arbitrary directions and arrangements around the foundation pit, and the study of the impact of soil displacement caused by dewatering and excavation on pipeline deformation and damage. It can also systematically reveal the influence of different pipeline arrangements on the response deformation of dewatering and excavation under the same test conditions. Attached Figure Description

[0017] Figure 1 The diagram shown is a three-dimensional structural schematic of the present invention. Figure 2 The diagram shows the assembly of the base and hydraulic simulation components of this invention. Figure 3 The diagram shown is a schematic representation of the simulated pipeline structure of the present invention. Figure 4 The diagram shown is a three-dimensional structural schematic of the excavation simulation mechanism of the present invention. Figure 5 Shown as the present invention Figure 4 Enlarged view of section A in the middle; Figure 6 The diagram shown is a three-dimensional structural schematic of the excavation component of the present invention. Figure 7 The image shown is a cross-sectional view of the excavation component of the present invention. Figure 8 The diagram shown is a three-dimensional structural schematic of the excavation unit of the present invention. Figure 9 The image shown is a cross-sectional view of the hydraulic simulation component of this invention.

[0018] Component designation explanation Base 1, Annular Groove 11, Simulation Groove 111, Slot 112, Divider 2, Sealing Strip 21, Simulation Pipeline 3, First Pipeline 31, Second Pipeline 32, Hydraulic Simulation Component 4, Water Supply Section 41, Water Supply Pipe 411, Branch Pipe 412, Dewatering Well 42, Water Hole 421, Recharge Well 43, Dewatering Pipe 44, Water Supply Pipe 45, First Vertical Pipe 46, Water Pump 461, Control Valve 462, First Spiral Pipe 47, Ring Pipe 48, Water Supply Tank 49, Wastewater Tank 410, Second Spiral Pipe 4101, Second Vertical Pipe 4102, Monitoring Component 5, Strain Gauge 51, Displacement Gauge 52, Pore Water Pressure Gauge 53, Flow Meter 54, Water Level Observation Well 55, Suspension Component 6, Suspension Plate 61, First Track 62, Annular Groove 621, Second Track 63, Inner Gear 64, external gear 65, moving part 66, moving mounting base 661, stabilizing roller 662, groove 6621, drive gear 663, moving power source 664, supporting roller 665, excavation assembly 7, fixed arm 71, vertical power unit 72, excavation part 73, connecting arm 731, mounting groove 7311, receiving cavity 732, drive rod 733, through space 7331, excavation unit 734, first ring body 7341, second ring body 7342, spiral cutter arm 7343, cutter teeth 7344, material conveying spiral blade 735, conveying channel 7351, material storage area 7352, excavation power unit 736, first gear 7361, second gear 7362, excavation power source 7363, sliding guide seat 74, sliding rod 75, balance plate 6. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0020] Please see Figures 1 to 9 It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0021] The following embodiments are for illustrative purposes only. These embodiments can be combined and are not limited to the content shown in any single embodiment below.

[0022] In this embodiment, please refer to Figures 1 to 9 The present invention provides a test device for the coupling effect of foundation pit dewatering and excavation on adjacent pipelines, comprising: a base 1, a simulated pipeline 3, a dewatering simulation mechanism and an excavation simulation mechanism; The base 1 has a downward-concave annular groove 11 on its top surface. The annular shape can eliminate stress concentration at corners. According to simulation needs, cohesive soil (relative to the impermeable layer) and sandy soil (confined aquifer) can be laid in layers from top to bottom inside the annular groove 11. The particle size of the soil is set according to the actual site conditions, which is common knowledge to those skilled in the art. For example, the confined aquifer sandy soil consists of coarse sand with a particle size of 0.3mm-2.2mm and fine sand with a particle size of 0.15-0.28mm, while the impermeable clay layer is cohesive soil with a particle size less than 0.005mm. The thickness of each soil layer can be adjusted according to the simulated working conditions, but it is necessary to ensure that each soil layer has a hole within the annular groove 11 that communicates with the hydraulic simulation component 4. This hole is used by the hydraulic simulation component 4 to control the water head pressure of each soil layer, and a soil-prevention mesh is installed at the hole location to prevent soil from entering and clogging it. The simulated pipeline 3 includes a first pipeline 31 and a second pipeline 32, and the annular groove 11 has a plurality of first pipelines 31 and / or a plurality of second pipelines 32. The precipitation simulation mechanism includes a hydraulic simulation component 4 and a monitoring component 5. The hydraulic simulation component 4 has a first state and a second state. The hydraulic simulation component 4 is configured to allow water to flow into the annular groove 11 in the first state to establish an initial water level, and to pump water from the simulated pit in the annular groove 11 in the second state. The monitoring component 5 is configured to acquire the internal state parameters of the annular groove 11 in real time during the test; the excavation simulation mechanism includes a suspension component 6 and at least two excavation components 7. The suspension component 6 is configured above the base 1 to drive the excavation components 7 to make circular motion around the axis of the annular groove 11, so as to change the spacing between the excavation components 7. The excavation assembly 7 includes a fixed arm 71, a vertical power unit 72, and an excavation part 73. The vertical power unit 72 includes an electric push rod, a cylinder, or a hydraulic cylinder. The fixed arm 71 is fixedly connected to the suspension assembly 6. The vertical power unit 72 is configured on the fixed arm 71 to drive the excavation part 73 to move in the vertical direction.

[0023] By linking and coordinating the dewatering simulation mechanism and the excavation simulation mechanism, simultaneous simulations of foundation pit dewatering and soil excavation can be conducted. This simulates the evolution of ground stress, water level, and settlement under the coupled effects of dual working conditions, as well as the superimposed disturbance deformation characteristics of adjacent underground pipelines. This allows for a comprehensive and realistic revelation of the disturbance mechanism of foundation pit construction on pipelines, thus improving the relevant theoretical research system. Through the configuration of at least two excavation components 7 and the circular motion function driven by the suspension component 6, the spacing between the excavation components 7 can be changed, enabling various cluster construction modes such as simultaneous excavation of multiple foundation pits and staggered excavation. This allows for the study of the coupling and superimposed disturbance mechanism between adjacent foundation pits. Furthermore, by independently driving each excavation component 7 and precisely controlling the excavation rate and depth by the vertical power unit 72, multivariate comparative experiments can be conducted with different foundation pit spacings, excavation sequences, and excavation rates. This systematically reveals the impact mechanism of cluster foundation pit construction on ground settlement and pipeline deformation, significantly improving the engineering adaptability and realism of the test results. In this embodiment, please refer to... Figure 3 Multiple first pipelines 31 are pipes and / or cables, and multiple second pipelines 32 are pipes and / or cables, which makes them fit the real laying environment of urban underground space and improves the engineering applicability of test results; Multiple first pipelines 31 within the same horizontal plane are collinear with and / or inclined at an angle to the central axis of the annular groove 11, and multiple second pipelines 32 within the same horizontal plane are perpendicular to and / or inclined at an angle to the central axis of the annular groove 11. The simulated foundation pit may be located between or on the side of the multiple first pipelines 31 and / or the multiple second pipelines 32, and a water-stop curtain is provided at the edge of the simulated foundation pit.

[0024] In this embodiment, please refer to Figure 3 Multiple first pipelines 31 are buried at the same and / or different depths, and multiple second pipelines 32 are buried at the same and / or different depths. By setting the burial depths of each first pipeline 31 and second pipeline 32 to be the same or different, the current situation of vertical layered arrangement of underground pipelines in the project can be restored. It can simulate both dense pipeline groups at the same burial depth and pipeline layouts with alternating depths, accurately study the differential disturbance law of uneven vertical and horizontal settlement of the stratum caused by foundation pit dewatering on pipelines at different burial depths, and improve the engineering applicability of the test results. And / or, multiple first pipelines 31 may be made of the same or different materials, and multiple second pipelines 32 may be made of the same or different materials; the first pipelines 31 and the second pipelines 32 may be made of the same or different materials, which can set up control groups for pipes with different stiffness such as steel pipes, PE pipes, concrete pipes, and plastic pipes, quantitatively analyze the differences in stress, strain, and damage modes of rigid and flexible pipelines under uneven displacement, clarify the influence mechanism of material factors on pipeline safety, and provide experimental basis for differentiated protection schemes for pipelines of different materials around the foundation pit; And / or, multiple first pipelines 31 may have the same and / or different diameters, and multiple second pipelines 32 may have the same and / or different diameters. By configuring first pipelines 31 and second pipelines 32 with the same or different diameters, the actual situation of large-diameter main pipelines and small-diameter branch pipelines interspersed in urban pipe networks can be reproduced, the differences in deformation resistance caused by differences in pipe diameter can be studied, the differences in deformation risk of pipelines with different diameters under precipitation disturbance can be analyzed, the experimental variables can be enriched, and the dimensions of pipe network safety evaluation can be improved.

[0025] By flexibly adjusting the burial depth, material, and diameter of the first pipeline 31 and the second pipeline 32, the actual engineering conditions of underground pipelines with varying depths, materials, and diameters can be replicated. Furthermore, single-variable or multi-variable coupled control experiments can be conducted to accurately study the influence of burial depth, pipe material, and pipe diameter on pipeline deformation caused by foundation pit dewatering. The device can switch test conditions without overall modification, is highly versatile, has controllable test variables, and provides high data comparison reliability, offering ample experimental support for optimizing underground pipeline protection schemes.

[0026] In this embodiment, please refer to Figure 1 and Figure 2It also includes at least two partition plates 2, which divide the annular groove 11 into two simulated troughs 111 for placing simulated foundation pit soil. Each simulated trough 111 has a drainage outlet at the bottom and a valve for controlling opening and closing is provided in the drainage outlet. The annular groove 11 has a slot 112 for detachably inserting the partition plate 2. A sealing strip 21 is provided on the side near both ends of the partition plate 2. The sealing strip 21 can be a U-shaped rubber strip. The partition plate 2 can be detachably plugged in and installed via slot 112, which can precisely limit and flexibly adjust the division pattern of the annular groove 11 to adapt to various working conditions in the control test. The sealing strip 21 on the partition plate 2 can seal the assembly gap, realize the water-proof seal between adjacent simulation tanks 111, effectively prevent water from flowing between simulation tanks 111, ensure that each simulation tank 111 is independent, improve the data accuracy of head control and monitoring, and facilitate disassembly, cleaning, and reuse, making the device more versatile and reliable. Multiple first pipelines 31 and / or multiple second pipelines 32 are placed in the soil according to the position requirements in the simulated working conditions. This can be done by setting multiple first pipelines 31 in one simulation tank 111 and multiple second pipelines 32 in another simulation tank 111, or by setting the first pipelines 31 and second pipelines 32 in the two simulation tanks 111 in the same or different arrangements. The excavation mechanism has at least four excavation components 7. By simulating the foundation pit between pipelines or on the side of pipelines, and combining it with a water-stop curtain structure, common engineering scenarios such as foundation pits adjacent to pipelines and foundation pits located in the middle of pipeline groups can be simulated respectively, and the disturbance law of foundation pit dewatering on surrounding underground pipelines can be studied in a targeted manner.

[0027] Through the design of at least two partition plates 2, simulated pipelines 3, dewatering simulation mechanism and excavation simulation mechanism, the first pipeline 31 in the same plane is arranged collinearly / inclined along the central axis of the annular groove 11, and the second pipeline 32 in the same plane is arranged perpendicular to the central axis / inclined. The two types of pipelines can be arranged separately in a single simulated groove 111, arranged differently in two grooves, or arranged in the same groove. This allows for the simulation of underground integrated pipe corridors, the reproduction of underground pipelines with arbitrary directions and arrangements around the foundation pit, and the study of the impact of soil displacement caused by dewatering and excavation on pipeline deformation and damage. It can also systematically reveal the influence of different pipeline arrangements on the response deformation of dewatering and excavation under the same test conditions.

[0028] In this embodiment, please refer to Figure 1 , Figures 4 to 8 The suspension assembly 6 includes a suspension plate 61, a first track 62, a second track 63, an internal gear 64, an external gear 65, and a moving part 66; The suspension plate 61 is ring-shaped and is fixedly connected to the upper part of the base 1. The first track 62 and the second track 63 are located above the suspension plate 61, and the central axes of the first track 62, the second track 63 and the suspension plate 61 are collinear. The internal gear 64 and the external gear 65 are coaxially fixed on the inner and outer sides of the suspension plate 61, respectively. The first track 62 and the second track 63 each have at least one moving part 66. The moving part 66 is configured to mesh with the internal gear 64 or the external gear 65, so that it can move circumferentially along the first track 62 or the second track 63, thereby driving the excavation component 7 to change position. The number of the excavation components 7 is equal to the total number of the moving parts 66 on the first track 62 and the second track 63.

[0029] The suspension assembly 6 uses the annular suspension plate 61 as the overall load-bearing base, and the first track 62 and the second track 63 are coaxially arranged. The inner gear 64 and the outer gear 65 are coaxially fixed on the inner and outer sides of the suspension plate 61. At least one moving part 66 is arranged on the first track 62 and the second track 63 respectively. The moving part 66 can move circumferentially along the first track 62 and the second track 63 to achieve rotational positioning around the central axis through meshing transmission with the inner gear 64 and the outer gear 65. The annular arrangement position and relative spacing of each moving part 66 can be flexibly and independently adjusted to simulate different foundation pit spacing and different foundation pit distribution forms. By ensuring a one-to-one correspondence between the number of excavation components 7 and the total number of all moving parts 66, each excavation component 7 is rigidly connected to the moving part 66 via a fixed arm 71, enabling the work position to be adjusted synchronously with the moving part 66. Simultaneously, each excavation component 7 is independently equipped with a vertical power unit 72 and an excavation unit 73. The vertical power unit 72 can independently drive the corresponding excavation unit 73 to complete vertical feeding, excavation, stopping excavation, and rate control, enabling multi-condition simulation of simultaneous excavation of multiple foundation pits, staggered excavation in stages, and differentiated rate excavation. This realistically reproduces the coupling and superposition effect of excavation of adjacent foundation pits, improving the authenticity of the experiment.

[0030] In this embodiment, please refer to Figure 4 and Figure 5 The moving part 66 includes a moving mounting base 661, a stabilizing roller 662, a drive gear 663, and a moving power source 664, wherein the moving power source 664 includes a motor; The stabilizing roller 662 is provided with a groove 6621 on its side; The motion mounting base 661 is located above the first track 62. Multiple stabilizing rollers 662 are rotatably mounted on both sides of the bottom surface of the motion mounting base 661. The rolling grooves 6621 on the stabilizing rollers 662 on both sides are respectively in rolling cooperation with the inner track and outer track of the first track 62, and the rolling axis is parallel to the central axis of the first track 62. The drive gear 663 is rotatably connected to the motion mounting base 661. The motion power source 664 of the motion part 66 located on the first track 62 drives the drive gear 663 to rotate and meshes with the internal gear 64 to make the motion part 66 perform circular motion around the central axis of the internal gear 64. The motion power source 664 of the moving part 66 located on the second track 63 drives the drive gear 663 to rotate and meshes with the external gear 65 to make the moving part 66 perform circular motion around the central axis of the external gear 65.

[0031] In another specific embodiment, a bearing may also be included, wherein the motion mounting seat 661 of the motion part 66 located on the first track 62 is fixedly connected to the inner ring of the bearing, and the outer ring is coaxially fixedly engaged with the base 1; the motion mounting seat 661 of the motion part 66 located on the second track 63 is fixedly connected to the outer ring of the bearing, and the inner ring is coaxially fixedly engaged with the base 1.

[0032] The moving part 66 arranged on the first track 62 is driven by the power source 664 to rotate the gear 663. The driving gear 663 meshes with the inner gear 64 on the inner side of the suspension plate 61, driving the entire moving part 66 to make precise circular motion around the central axis along the first track 62. The moving part 66 arranged on the second track 63 is driven by the power source 664 to rotate the gear 663. The driving gear 663 meshes with the outer gear 65 on the outer side of the suspension plate 61, driving the entire moving part 66 to make circular motion around the central axis along the second track 63. This enables precise and controllable adjustment of the rotation angle and circumferential position of each moving part 66, thereby precisely changing the annular arrangement position and relative spacing of each excavation component 7.

[0033] Both the first track 62 and the second track 63 have annular grooves 621 on their top surfaces along their circumference. The bottom surface of the motion mounting base 661 is provided with a support roller 665 that rolls with the annular grooves 621. The rolling axis of the support roller 665 is perpendicular to the central axis of the first track 62. The support roller 665 plays the role of transferring the load on the motion mounting frame to the first track 62 and the second track 63, and at the same time enhances the motion capability of the motion part 66. Multiple sets of annular grooves 621 and multiple sets of support rollers 665 can be arranged in parallel to enhance the load-bearing capacity and stability of the motion part 66.

[0034] In this embodiment, please refer to Figures 6 to 8 The excavation section 73 includes a connecting arm 731, which is fixedly connected to the telescopic end of the vertical power section 72. A receiving cavity 732 is fixedly connected to the connecting arm 731 and has an internal space extending axially; A drive rod 733 is rotatably connected to the receiving cavity 732. The top end of the drive rod 733 extends out of the receiving cavity 732, and the bottom end is fixedly connected to an excavation unit 734. The drive rod 733 forms a through space 7331 along its own axis for the dewatering well 42 to pass through. A conveying auger 735 is disposed at the middle position to the bottom of the drive rod 733. The conveying auger 735 contacts and engages with the inner surface of the receiving cavity 732 to form a conveying channel 7351 for conveying soil from bottom to top along the axial direction. A storage area 7352 is formed between the top and circumferential sidewalls of the receiving cavity 732 and the top of the conveying auger 735. The excavation power unit 736 is used to drive the drive rod 733 to rotate, so as to drive the excavation unit 734 to excavate the simulated foundation pit soil.

[0035] The moving part 66 moves along the first track 62 and the second track 63, precisely positioning each excavation component 7 to the preset center point of the simulated foundation pit. The vertical power unit 72 extends, pressing the connecting arm 731 along with the entire excavation part 73 down to the surface of the simulated soil, establishing the initial excavation point. The excavation power unit 736 is then activated, and the drive rod 733 drives the bottom excavation unit 734 to rotate and cut the simulated strata. The cut soil is conveyed upward along the inner surface of the receiving cavity 732 by the conveying screw 735 in the lower part of the drive rod 733, forming an axial upward conveying channel 7351, and stored in the storage area 7352. This allows the vertical power unit 72 to continuously feed downward without stopping for cleaning, avoiding the redistribution of strata stress caused by frequent shutdowns. Furthermore, the axial penetration of the space 7331 by the drive rod 733 allows for simultaneous pit dewatering simulation tests throughout the entire excavation process.

[0036] In this embodiment, please refer to Figure 8 The excavation unit 734 includes a first ring body 7341, which is coaxially rotatably connected to the bottom end of the receiving cavity 732. The second ring body 7342 is coaxially disposed below the first ring body 7341 and is coaxially fixedly engaged with the bottom end of the drive rod 733. Multiple helical cutter arms 7343 are evenly spaced along the circumference of the first ring body 7341. Each helical cutter arm 7343 is fixedly connected to the first ring body 7341 and the second ring body 7342 at both ends. Each helical cutter arm 7343 has a number of cutter teeth 7344 along its own helical direction.

[0037] During the simulated excavation of the foundation pit, the drive rod 733 drives the overall excavation unit 734 to rotate at high speed coaxially. The spiral cutter arm 7343 uses its own spiral angle and surface array of cutter teeth 7344 to cut and break the simulated soil below. With the uniform vertical feed of the vertical power unit 72, the soil is peeled off layer by layer and cut into neat shapes. At the same time, the spiral structure of the spiral cutter arm 7343 can guide the cut and broken soil upwards and smoothly connect with the conveying spiral blade 735 of the upper drive rod 733, so that the broken soil enters the cavity conveying channel smoothly, realizing the integrated continuous operation of cutting, guiding, conveying and storing materials.

[0038] The excavation power unit 736 includes a first gear 7361, a second gear 7362, and an excavation power source 7363. The excavation power source 7363 includes a motor. An installation groove 7311 is provided on the connecting arm 731. The first gear 7361 is rotatably connected to the installation groove 7311. The second gear 7362 is coaxially fixedly engaged with the drive rod 733. The output power of the excavation power source 7363 is transmitted to the drive rod 733 through the meshing of the first gear 7361 and the second gear 7362, enabling the drive rod 733 to rotate around its own axis. The excavation power source 7363 drives the first gear 7361 to rotate. Through the meshing of the first gear 7361 and the second gear 7362, power is smoothly transmitted to the second gear 7362, thereby driving the drive rod 733 and the bottom integrated excavation unit 734 to rotate around their own axes, providing stable torque and speed for the cutting and breaking operations of the foundation pit soil.

[0039] The excavation assembly 7 also includes two sliding guide seats 74 and two sliding rods 75. The two sliding guide seats 74 are disposed on the fixed arm 71 and are symmetrically arranged along the vertical power unit 72. The two sliding rods 75 slide through the sliding guide seats 74. During the entire process of the vertical power unit 72 driving the excavation unit 73 to vertically feed and return, the sliding cooperation between the sliding guide seats 74 and the sliding rods 75 provides bidirectional vertical guidance and radial limitation for the telescopic end of the vertical power unit 72, the connecting arm 731, and the entire excavation unit 73, constraining the excavation assembly 7 to only make linear displacement in the vertical direction and limiting its horizontal swaying, yaw, and torsional displacement.

[0040] A balance plate 6 is fixedly sleeved between adjacent slide rods 75. The balance plate 6 is disposed above the slide guide seat 74, so that the two independent slide rods 75 can achieve synchronous linkage and synchronous sliding, ensuring that the connecting arm 731 always maintains a horizontal state.

[0041] In this embodiment, please refer to Figure 2 and Figure 9 The hydraulic simulation component 4 includes a water supply unit 41, a dewatering well 42, a dewatering pipe 44, and a first vertical pipe 46. The number of the dewatering well 42, the dewatering pipe 44, and the simulation tank 111 are equal. The dewatering well 42 is located inside the simulated foundation pit. The insertion end of the dewatering well 42 has a number of water holes 421 evenly arranged along its own axial and circumferential directions. A filter screen is provided on the outside of the water holes 421. The filter screen can be made of nylon filter cloth and has multiple layers, so as to achieve multi-layer gradient filtration, take into account both water permeability and sand blocking effect, prevent fine soil particles from flowing into the well, and avoid blockage and failure of the dewatering well 42 and the recharge well 43 pipeline.

[0042] One end of the downwater pipe 44 is located inside the downwater well 42. Both the first vertical pipe 46 and the downwater pipe 44 are equipped with a water pump 461 and a control valve 462. The control valve 462 includes a one-way valve and an on / off valve. The water pumps 461 on the first vertical pipe 46 and the downwater pipe 44 are located in the water supply tank 49 and the downwater well 42, respectively. During the test, the other end of the downwater pipe 44 is connected to the second spiral pipe 4101 through a quick connector. The quick connector facilitates the disassembly and assembly of the pipeline and the cleaning of the equipment before and after the test. The quick connector is a common type of quick connector and is common knowledge to those skilled in the art. The water supply unit 41 is connected to the first vertical pipe 46 to provide an initial water level for the simulation tank 111.

[0043] The hydraulic simulation component 4 also includes at least two recharge wells 43, at least two water supply pipes 45, at least two first spiral pipes 47 and a ring pipe 48. The number of recharge wells 43, water supply pipes 45 and first spiral pipes 47 are equal. The dewatering wells 42 and recharge wells 43 can be made of PVC material. The dewatering well 42 and the recharge well 43 have the same structure. The recharge well 43 is located between the simulated foundation pit and the first pipeline 31 and the second pipeline 32. That is, the recharge well 43 can be arranged between the foundation pit and the adjacent pipeline, and adjacent recharge wells 43 can be staggered. The ring pipe 48 is disposed on the top edge of the base 1. One end of the first vertical pipe 46 and the first spiral pipe 47 are respectively connected to the ring pipe 48. The end of the first spiral pipe 47 connected to the ring pipe 48 is provided with a solenoid valve. The solenoid valve on each first spiral pipe 47 can be opened and closed independently. One end of the water supply pipe 45 is located in the reinjection well 43. During the test, the other end of the water supply pipe 45 is connected to the other end of the first spiral pipe 47 through a quick connector. In the first state, the water supply unit 41 injects water into the annular groove 11 or the two simulated trenches 111 through the pre-reserved connecting holes in each soil layer to provide the initial water level; in the second state, the water pump 461 of the dewatering pipe 44 is turned on and the valve is turned on and off, and the dewatering well 42 collects the groundwater in the pit through the permeable holes 421 evenly distributed in the well wall, and pumps it out through the dewatering pipe 44 to simulate the process of depressurization and dewatering of the confined water in the pit; the one-way valve in the pipeline can prevent the backflow of groundwater after the pumping stops, and ensure that the pumping flow and the water level in the pit are stable and controllable. According to the test plan, the water pump 461 and control valve 462 on the first vertical pipe 46 and the solenoid valve on the first spiral pipe 47 are turned on. Water flows through the ring pipe 48, the first spiral pipe 47 and the water supply pipe 45 and is sent into the recharge well 43 between the foundation pit and the pipeline. The recharge well 43 replenishes water evenly to the soil outside the foundation pit and around the pipeline through the water permeable holes 421 in the well wall to raise the water head, offset the water head drop caused by the foundation pit dewatering, and simulates the engineering measures of recharge to protect the underground pipeline. Multiple sets of independent recharge branches can realize multi-point synchronous or differentiated water replenishment, and restore the on-site well group recharge working conditions.

[0044] The number of water supply units 41 is equal to the number of simulation tanks 111. Each water supply unit 41 includes a water supply pipe 411 and multiple branch pipes 412. The water supply pipe 411 is connected to the first vertical pipe 46, and the connection point is located between the control valve 462 and the water pump 461. The water supply pipe 411 may be equipped with an openable / closable valve. The multiple branch pipes 412 are arranged at intervals along the vertical height of the simulation tank 111, connecting the water supply pipe 411 to the simulation tank 111. Each branch pipe 412 is equipped with an openable / closable valve. The multiple branch pipes 412 are arranged at intervals along the vertical height of the simulation tank 111, and can connect to different strata (upper cohesive impermeable layer, lower pressure-bearing sand layer). With the independent valves of each branch pipe 412, water can be injected into each soil layer individually to stabilize the pressure, establishing an initial groundwater level layer by layer, accurately simulating the original pressure-bearing state of a multi-layered hydrogeological structure.

[0045] Initial water level preparation stage: Open the water pump 461 on the first vertical pipe 46 and the valve on the water supply pipe 411. Water flows through the water supply pipe 411 to each branch pipe 412. According to the height of the test soil layer, open the valve of the branch pipe 412 at the corresponding height. The water flow is delivered through the branch pipe 412 to the soil layer at the corresponding depth. Water is injected into the cohesive aquitard and the confined aquifer. Observe the data fed back by the monitoring component 5. After the water head at the layer stabilizes, close the main valve of the water supply pipe 411 to complete the initial hydrological boundary setting.

[0046] The hydraulic simulation component 4 also includes a water supply tank 49 and a wastewater tank 410; The water supply trough 49 is located outside the base 1 and is ring-shaped. The central axis of the water supply trough 49 is collinear with the central axis of the annular groove 11. The other end of the first vertical pipe 46 extends into the water supply trough 49. The wastewater tank 410 is located outside the water supply tank 49. The other end of the downcomer 44 is connected to the wastewater tank 410 through a second spiral pipe 4101 and a second vertical pipe 4102. The bottom surface of the wastewater tank 410 is higher than the bottom surface of the water supply tank 49. Filter holes communicating with the water supply tank 49 are formed circumferentially on the sidewall of the wastewater tank 410. The drain outlet can also be connected to the wastewater tank 410 through a drain pipe, and a water pump 461 is installed on the drain pipe. Because the bottom surface of the wastewater tank 410 is higher than the bottom surface of the water supply tank 49, gravity drainage is achieved due to the difference in liquid level. The circumferentially arranged filter holes on the sidewall of the wastewater tank 410 allow wastewater to flow back to the inner water supply tank 49 for recycling, achieving gravity-flow filtration and reuse of wastewater, reducing experimental water consumption, saving energy and protecting the environment, and lowering the water cost of multiple experiments.

[0047] The monitoring component 5 includes a plurality of strain gauges 51, which are respectively disposed on the inner and outer surfaces of the first pipeline 31 and the second pipeline 32 to monitor the displacement, bending moment, and axial force of the first pipeline 31 and the second pipeline 32. Dewatering of the foundation pit causes uneven soil settlement, resulting in compression, tension, and bending forces on the first pipeline 31 and the second pipeline 32. The pipelines undergo slight deformation, and the strain gauges 51 attached to the inner and outer walls of the pipeline deform synchronously with the pipeline, causing corresponding changes in their resistance values. The data acquisition unit collects the strain resistance signals in real time, obtains the strain values ​​at various points along the pipeline through conversion formulas, and further calculates the axial displacement, axial force, and bending moment of the pipeline to determine its stress safety status. Earth pressure gauges, multiple earth pressure gauges are evenly arranged vertically along the outside of the waterstop curtain to monitor earth pressure; Displacement gauge 52 is located on the surface of the simulated soil to monitor the settlement of the surrounding ground. It can measure the deformation at different locations of the soil. The displacement gauge 52 is arranged at different locations on the soil surface to obtain surface settlement data at multiple locations around the foundation pit and along the pipeline. It can draw the spatial distribution curve of surface settlement, analyze the uneven settlement law of the strata under the action of precipitation, and quantify the differences in soil deformation at the locations of pipelines with different burial depths, materials, and orientations. It provides surface deformation data support for pipeline protection and water-stop curtain optimization. The pore water pressure gauge 53 is used to measure the pore water pressure at different depths in the confined aquifer. Multiple gauges can be installed at different depths in the soil to calculate the water level changes. The pore water pressure gauges 53 are vertically layered and installed at different depths in the confined aquifer and impermeable layer. They can monitor the dynamic changes of pore water pressure at each layer in real time, calculate the groundwater level development process, and clearly reflect the protective effect of dewatering and external recharge on the aquifer head. A flow meter 54 is installed on the hydraulic simulation component 4 to measure the flow rate of pumping and replenishing water when the hydraulic simulation component 4 is in the second state. The flow meter 54 can be installed on the dewatering pipe 44 and the replenishment pipe 45 respectively, and can record the pumping volume of the foundation pit and the replenishment volume of each reinjection well 43 in real time. Combined with pore water pressure, settlement and pipeline strain data, a quantitative correspondence of "water volume-water head-formation deformation-pipeline stress" is established to accurately analyze the degree of disturbance of pumping rate and reinjection flow rate to the surrounding environment and pipeline. The data acquisition unit includes strain gauges 51, displacement gauges 52, pore water pressure gauges 53, and flow meters 54, all electrically connected to it. The data acquisition unit can be a DataTaker automated data acquisition instrument, capable of continuously recording precipitation data throughout the entire experimental process around the clock. The data is automatically stored, facilitating subsequent data fitting, modeling, and analysis. The experimental process can be completely reproduced, resulting in more scientifically sound experimental conclusions.

[0048] The monitoring component 5 also includes water pipe observation wells and water level gauges. There are multiple water level observation wells 55, which are located outside the simulated foundation pit between the first pipeline 31 and the second pipeline 32, and on the side of the first pipeline 31 and the second pipeline 32 away from the simulated foundation pit. The water level gauges are respectively located inside the water level observation wells 55 and inside the dewatering wells 42 of the hydraulic simulation component 4. By arranging water level observation wells 55 at multiple points between the foundation pit and the pipeline, and on the side of the pipeline away from the foundation pit, and installing water level gauges in the observation wells and dewatering wells 42, the groundwater level changes in the near-site area of ​​the foundation pit, the pipeline protection area, and the outer area can be monitored in segments. This allows for accurate depiction of the dewatering distribution and a direct evaluation of the head protection effect of the cutoff wall and recharge measures on the pipeline area. At the same time, the data is cross-checked with the monitoring data of the pore water pressure gauge 53 to improve the accuracy of water level monitoring. It can also quantify the degree of hydraulic disturbance in the pipeline area. The experimental layout is consistent with the actual project and provides a reliable hydrological monitoring basis for optimizing the safety protection scheme for pipelines around the foundation pit.

[0049] In this embodiment, please refer to Figures 1 to 9 A test method for a test device for the coupled effect of foundation pit dewatering excavation on adjacent pipelines, applicable to the test device for the coupled effect of foundation pit dewatering excavation on adjacent pipelines, includes the following steps: Soil laying steps: According to the test requirements, a cohesive relative water-resistant layer and a sandy confined aquifer with a specified particle size are laid in the annular groove 11. According to the test plan, dewatering wells 42 are buried at predetermined elevations and positions. The first pipeline 31 and / or the second pipeline 32 are buried at preset positions respectively. The first pipeline 31 and the second pipeline 32 with different burial depths, different materials, and different pipe diameters can be set. The monitoring component 5 is set in the annular groove 11. The dewatering well 42 is set at the center of the simulated foundation pit. Simulated foundation pit selection steps: Select the location of the simulated foundation pit, and install a water-stop curtain at the edge of the foundation pit. The insertion depth of the water-stop curtain can be the same or different. Initial positioning steps for excavation: each of the excavation components 7 is placed at the preset center point of the simulated foundation pit, the vertical power unit 72 extends out, the dewatering well 42 passes through the center of the excavation part 73, and as the excavation part 73 moves downward, the dewatering well 42 extends out of the top of the excavation part 73. One end of the dewatering pipe 44 is located inside the dewatering well 42, and the other end is connected to the second spiral pipe 4101 through a quick connector; Initial water level setting steps: When the hydraulic simulation component 4 is in the first state, water is injected into the concave groove through the pre-reserved interconnected holes of each soil layer to apply a preset initial water head to the impermeable layer and the confined aquifer respectively. After standing for 24 hours, when the soil layer has completed consolidation and settlement, fill the soil to the set elevation. After standing and stabilizing, the monitoring component 5 collects the initial foundation parameters in real time to complete the calibration of the initial test conditions. Water-induced excavation simulation steps: When the hydraulic simulation component 4 is in the second state, water is first pumped out from the simulated foundation pit in the annular groove 11 and left to stand for 30 minutes. Then, the vertical power unit 72 is started to drive the excavation unit 73 to move downward to the predetermined excavation depth and stays to stand for 30 minutes. Data is collected in real time through the monitoring component 5 throughout the process. The above process is repeated until the test ends.

[0050] In summary, this invention, through the coordinated operation of the dewatering simulation mechanism and the excavation simulation mechanism, can simultaneously simulate foundation pit dewatering and soil excavation. It simulates the evolution of ground stress, water level, and settlement under the coupled effects of dual working conditions, as well as the superimposed disturbance deformation characteristics of adjacent underground pipelines. This allows for a comprehensive and realistic revelation of the disturbance mechanism of foundation pit construction on pipelines, thus improving the relevant theoretical research system. By configuring at least two excavation components 7 and utilizing the circular motion function driven by the suspension component 6, the spacing between the excavation components 7 can be changed, enabling various cluster construction modes such as simultaneous excavation of multiple foundation pits and staggered excavation. This allows for the study of the coupling and superimposed disturbance mechanism between adjacent foundation pits. Furthermore, by independently driving each excavation component 7 and precisely controlling the excavation rate and depth by the vertical power unit 72, multivariate comparative experiments with different foundation pit spacings, excavation sequences, and excavation rates can be conducted. This systematically reveals the impact mechanism of cluster foundation pit construction on ground settlement and pipeline deformation, significantly improving the engineering adaptability and realism of the experimental results. Through the design of at least two partition plates 2, simulated pipelines 3, a dewatering simulation mechanism, and an excavation simulation mechanism, the first pipeline 31 in the same plane is arranged collinearly / inclined along the central axis of the annular groove 11, and the second pipeline 32 in the same plane is arranged perpendicular to / inclined to the central axis. The two types of pipelines can be arranged individually in a single simulated groove 111, arranged differently in two grooves, or arranged mixed in the same groove. This allows for the simulation of underground integrated utility tunnels, the reproduction of underground pipelines with arbitrary directions and arrangements around the foundation pit, and the study of the impact of soil displacement caused by dewatering and excavation on pipeline deformation and damage. It also systematically reveals the influence of different pipeline arrangements on the response deformation of dewatering and excavation under the same test conditions. Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0051] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A test device for coupling the dewatering excavation of a foundation pit with the action of an adjacent pipeline, characterized in that, include: The base has a downwardly recessed annular groove on its top surface; The simulated pipeline includes a first pipeline and a second pipeline, and the annular groove has a plurality of the first pipelines and / or a plurality of the second pipelines; A precipitation simulation mechanism, comprising a hydraulic simulation component and a monitoring component, wherein the hydraulic simulation component has a first state and a second state, wherein the hydraulic simulation component is configured to allow water to flow into the annular groove in the first state to establish an initial water level, and to pump water from a simulated pit in the annular groove in the second state. The monitoring component is configured to acquire the internal state parameters of the annular groove in real time during the test. An excavation simulation mechanism includes a suspension assembly and at least two excavation assemblies. The suspension assembly is configured above the base to drive the excavation assemblies to perform circular motion around the axis of the annular groove, thereby changing the spacing between the excavation assemblies. The excavation assembly includes a fixed arm, a vertical power unit, and an excavation part. The fixed arm is fixedly connected to the suspension assembly, and the vertical power unit is configured on the fixed arm to drive the excavation part to move in the vertical direction.

2. The test device for coupling the dewatering excavation of the foundation pit with the adjacent pipeline as described in claim 1, characterized in that: The plurality of first pipelines are pipes and / or cables, and the plurality of second pipelines are pipes and / or cables; Multiple first pipelines within the same horizontal plane are arranged collinearly with and / or at an angle to the central axis of the annular groove, and multiple second pipelines within the same horizontal plane are arranged perpendicularly to and / or at an angle to the central axis of the annular groove.

3. The test device for coupling the dewatering excavation of the foundation pit with the adjacent pipeline as described in claim 1, characterized in that: Multiple first pipelines are buried at the same and / or different depths, and multiple second pipelines are buried at the same and / or different depths; And / or, multiple first pipelines are made of the same and / or different materials, and multiple second pipelines are made of the same and / or different materials; And / or, multiple first pipelines have the same and / or different diameters, and multiple second pipelines have the same and / or different diameters.

4. The test device for coupling the dewatering excavation of the foundation pit with the adjacent pipeline as described in claim 1, characterized in that: It also includes at least two partition plates, which divide the annular groove into two simulated slots for placing simulated foundation pit soil. The excavation mechanism has at least four excavation components.

5. The test device for coupling the dewatering excavation of the foundation pit with the adjacent pipeline as described in claim 1, characterized in that: The suspension assembly includes a suspension plate, a first track, a second track, an internal gear, an external gear, and a moving part; The suspension plate is ring-shaped, and the first track and the second track are located above the suspension plate. The central axis of the first track, the second track and the suspension plate are collinear. The internal gear and the external gear are coaxially fixed to the inner and outer sides of the suspension plate, respectively. The first track and the second track each have at least one moving part. The moving part is configured to mesh with the internal gear or the external gear to make circumferential movement along the first track or the second track, thereby driving the excavation component to change position. The number of excavation components is equal to the sum of the number of moving parts on the first track and the second track.

6. The test device for coupling the dewatering excavation of a foundation pit with the adjacent pipeline as described in claim 1, characterized in that: The moving part includes a motion mounting base, stabilizing rollers, drive gears, and a motion power source; The stabilizing roller has a groove on its side; The motion mounting base is located above the first track. Multiple stabilizing rollers are rotatably mounted on both sides of the bottom surface of the motion mounting base. The grooves on the stabilizing rollers on both sides are respectively in rolling cooperation with the inner and outer tracks of the first track, and the rolling axis is parallel to the central axis of the first track. The drive gear is rotatably connected to the motion mounting base. The motion power source of the moving part located on the first track drives the drive gear to rotate and meshes with the internal gear to make the moving part perform circular motion around the central axis of the internal gear. The motion power source of the moving part located on the second track drives the drive gear to rotate and meshes with the external gear to make the moving part perform circular motion around the central axis of the external gear.

7. The test device for coupling the dewatering excavation of a foundation pit with the adjacent pipeline as described in claim 1, characterized in that: The excavation section includes a connecting arm, which is fixedly connected to the telescopic end of the vertical power section; A receiving cavity, the receiving cavity being fixedly connected to the connecting arm and having an internal space extending axially; A drive rod is rotatably connected to the receiving cavity. The top end of the drive rod extends out of the receiving cavity, and the bottom end is fixedly connected to an excavation unit. The drive rod forms a through space along its own axis for the dewatering well to pass through. The conveying screw is located from the middle to the bottom of the drive rod. The conveying screw contacts and engages with the inner surface of the receiving cavity to form a conveying channel for conveying soil from bottom to top along the axial direction. A storage area is formed between the top of the receiving cavity and the circumferential sidewall and the top of the conveying screw. The excavation power unit is used to drive the drive rod to rotate, so as to drive the excavation unit to excavate the simulated foundation pit soil.

8. The test device for coupling the dewatering excavation of a foundation pit with the adjacent pipeline as described in claim 7, characterized in that: The excavation unit includes a first ring body, which is coaxially rotatably connected to the bottom end of the receiving cavity; The second ring body is coaxially disposed below the first ring body and is coaxially fixedly engaged with the bottom end of the drive rod; Multiple helical cutter arms are evenly spaced along the circumference of the first ring body. Each helical cutter arm is fixedly connected to the first ring body and the second ring body at both ends, and each helical cutter arm has a number of cutting teeth along its own helical direction.

9. The test device for coupling the dewatering excavation of a foundation pit with the adjacent pipeline as described in claim 1, characterized in that: The hydraulic simulation component includes a water supply unit, a dewatering well, a dewatering pipe, and a first vertical pipe, wherein the number of the dewatering well, the dewatering pipe, and the simulation tank are equal; The dewatering well is located inside the simulated foundation pit, and the insertion end of the dewatering well has several water holes evenly arranged along its own axial and circumferential directions. One end of the dewatering pipe is located inside the dewatering well. Both the first vertical pipe and the dewatering pipe are equipped with water pumps and control valves. During the test, the other end of the dewatering pipe is connected to the second spiral pipe through a quick connector. The water supply unit is connected to the first vertical pipe to provide an initial water level for the simulation tank.

10. A test method for a test device for coupling the dewatering excavation of a foundation pit with the adjacent pipeline, characterized in that: The test apparatus applicable to the coupled action of foundation pit dewatering excavation on adjacent pipelines as described in claim 9 includes the following steps: Soil laying steps: According to the test requirements, a cohesive relatively impermeable layer and a sandy confined aquifer with a specified particle size are laid in the annular groove. According to the test plan, dewatering wells are buried at predetermined elevations and positions. The first pipeline and / or the second pipeline are buried at preset positions. The monitoring component is set in the annular groove, wherein the dewatering well is set at the center of the simulated foundation pit. Simulated foundation pit selection steps: Select the location of the simulated foundation pit and install a water-stop curtain at the edge of the foundation pit; Initial positioning steps for excavation: Place each of the excavation components at the preset center point of the simulated foundation pit, extend the vertical power unit, pass the dewatering well through the center of the excavation part, and as the excavation part moves downward, the dewatering well extends out of the top of the excavation part. One end of the dewatering pipe is located in the dewatering well, and the other end is connected to the second spiral pipe through a quick connector. Initial water level setting steps: When the hydraulic simulation component is in the first state, water is injected into the concave groove through the pre-reserved interconnected holes in each soil layer to apply a preset initial water head to the impermeable layer and the confined aquifer respectively. After static stabilization, the monitoring component collects the initial basic parameters in real time to complete the calibration of the initial test conditions. The water-induced excavation simulation steps are as follows: When the hydraulic simulation component is in the second state, water is first pumped out from the simulated foundation pit in the annular groove and left to stand for 30 minutes. Then, the vertical power unit is activated to drive the excavation unit to move downward to the predetermined excavation depth and stays for 30 minutes. Throughout the process, data is collected in real time through the monitoring component. The above process is repeated until the test ends.

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