A ground settlement device for simulating well flow stratified pumping

Abstract

This utility model relates to the field of land settlement simulation technology, and discloses a land settlement device for simulating well flow stratified pumping, including a model box, an injection pipe, a pumping pipe, a water pump, a pressure measuring pipe, an earth pressure sensor, and a pore pressure sensor. The model box is cylindrical and is filled with alternating layers of clay and sand. A pumping pipe is installed along the central axis of the model box, and the injection pipe extends into it from the outside to the inside circumferentially. The pumping pipe has a multi-layered casing structure, with sealing airbags between the casings. The inner casing extends to a deeper sand layer, and the outer casing extends to a shallower sand layer. The pressure measuring pipe is installed within the depth range of each of the multiple sand-filled layers. Each casing of the injection pipe is connected to a water pump. Earth pressure sensors and pore pressure sensors are uniformly and symmetrically arranged inside the model box. This utility model aims to construct a geotechnical test chamber and simulate the radial flow field characteristics of a pumping well point through stratified pumping control, providing support for water-based well drilling projects.

Description

Technical Field

[0001] This utility model relates to the field of ground subsidence simulation technology, and in particular to a ground subsidence device for simulating well flow stratified pumping. Background Technology

[0002] Groundwater, as an important freshwater resource, is widely extracted globally to meet the needs of agricultural irrigation, industrial production, and urban life. However, large-scale, long-term groundwater extraction significantly reduces the hydraulic head pressure of aquifers, leading to compaction and deformation of the aquifers and overlying soil layers, ultimately causing land subsidence. This subsidence is characterized by its irreversibility, cumulative nature, and wide-ranging impact, posing a serious threat to infrastructure (such as buildings, roads, bridges, and underground pipelines), flood control projects, urban drainage systems, high-speed railways, and the ecological environment. It has become a major geological and environmental hazard problem globally, especially in low-lying coastal areas and cities on large alluvial plains.

[0003] To study the causes and mechanisms of land subsidence, physical model tests are used for analysis. However, current physical model tests, both domestically and internationally, have significant shortcomings in simulating large-scale, multi-layered aquifer system subsidence caused by pumping. These shortcomings mainly include: the model size being too small, making it difficult to accurately reflect the spatial scale and boundary effects of the actual aquifer system, leading to distortion of the physical process; insufficient precision in pumping control and monitoring, with limited ability to precisely control the location, flow rate, and pumping process of pumping wells, and low accuracy in key parameters such as surface displacement, pore water pressure, and soil pressure; and the fact that most current model boxes use cuboid or cubic frames, resulting in localized stress concentrations within the model box, causing the subsidence process to not match reality. Utility Model Content

[0004] To address existing problems, this utility model provides a ground settlement device for simulating well flow stratified pumping. The purpose is to construct a cylindrical geotechnical test chamber that fully considers the marginal effect. By controlling pumping in layers, it simulates the three-dimensional radial flow field characteristics caused by point source pumping from a pumping well, monitors the seepage path and soil deformation, and provides physical experimental support for mechanism research, model verification, and disaster prevention in large-scale drinking water well drilling projects.

[0005] To achieve the above objectives, the present invention provides the following technical solution.

[0006] A ground settlement device simulating well flow stratified pumping includes a model box, an injection pipe, a pumping pipe, a water pump, a pressure measuring pipe, an earth pressure sensor, and a pore pressure sensor. The model box is cylindrical and is filled with alternating layers of clay and sand. The pumping pipe is installed along its central axis inside the model box, and extends into the injection pipe from the outside to the inside along its circumference. The pumping pipe has a multi-layered casing structure, with sealing airbags between the casings. The inner casing extends to the deeper sand layer, and the outer casing extends to the shallower sand layer. The pressure measuring pipe is installed within the depth range of each of the multiple sand-filled layers. Each casing of the injection pipe is connected to a water pump. Earth pressure sensors and pore pressure sensors are uniformly and symmetrically arranged inside the model box.

[0007] As a further improvement of this utility model, the water injection pipe includes a water distribution pipe and a flexible connecting pipe; the water distribution pipe is an internally connected square pipe matrix, one end of the water distribution pipe is connected to the water source pipe through a water injection hole, and the other end is connected to another water distribution pipe through a flexible connecting pipe.

[0008] As a further improvement of this utility model, the water distribution pipes are symmetrically and evenly arranged in the model box for immersing the sand layer and clay layer.

[0009] As a further improvement of this utility model, water outlet holes are evenly arranged on the water distribution pipe.

[0010] As a further improvement of this utility model, the soil pressure sensor and the pore pressure sensor are arranged orthogonally and symmetrically along the central axis of the model box.

[0011] As a further improvement of this utility model, it also includes displacement sensors; displacement sensors are uniformly and symmetrically arranged inside the model box.

[0012] As a further improvement of this utility model, the displacement sensor is arranged symmetrically along the central axis of the model box.

[0013] As a further improvement of this utility model, support legs are provided on the outer side of the model box.

[0014] As a further improvement of this utility model, a water stop valve is provided on the water pumping pipe.

[0015] As a further improvement of this utility model, the sleeve of the water pumping pipe is composed of multiple sleeve pipe sections spliced ​​together.

[0016] This utility model has the following beneficial effects:

[0017] This comprehensive device design can simulate real geological environments (interlaced clay and sand layers) and the well flow stratified pumping process, providing near-realistic experimental conditions for studying land subsidence and helping to gain a deeper understanding of the impact mechanism of stratified pumping on land subsidence.

[0018] Preferably, the water distribution pipes and flexible connecting pipes are used. The water distribution pipes are internally interconnected square pipe matrices. This structural design makes the water injection process more uniform and controllable. The square pipe matrix can expand the water injection range, while the flexible connecting pipes increase the flexibility of the pipe layout, allowing the water pumping pipes located along the central axis to be avoided. This facilitates adjustments based on the device layout within the model box, ensuring that water can be injected evenly into different layers and positions.

[0019] Preferably, a symmetrical and uniform arrangement of water distribution pipes can ensure that the sand and clay layers are consistently wetted by water in all directions, avoiding local geological differences caused by uneven water injection, thereby improving the accuracy and reliability of experimental results.

[0020] Preferably, the uniformly arranged water outlets enable water to flow out of the pipe at a relatively uniform flow rate and volume, further ensuring the uniform distribution of water in the sand and clay layers, simulating a more realistic groundwater recharge situation, and facilitating accurate research on the impact of stratified pumping on land subsidence.

[0021] Preferably, an orthogonal symmetrical arrangement can comprehensively and accurately measure the changes in earth pressure and water pressure at different locations and directions within the model box. This arrangement facilitates the systematic deployment and numbering of sensors, the identification of data anomalies, and the acquisition of more comprehensive and richer data. It also helps to deeply analyze the distribution patterns of earth pressure and water pressure under different pumping conditions and their impact on ground settlement, thereby improving the completeness of experimental data and the accuracy of analysis.

[0022] Preferably, the displacement sensors can monitor the displacement changes of each point in the model box in real time. The uniform and symmetrical arrangement can comprehensively reflect the spatial distribution of ground settlement, help engineers accurately understand the deformation characteristics of the ground during the stratified pumping process, simulate the local soil composition and settlement mechanism, and guide the development of well drilling projects.

[0023] Preferably, the centrally symmetrical arrangement further optimizes the monitoring effect of the displacement sensor, enabling it to more accurately capture changes in ground settlement with the central axis as the axis of symmetry.

[0024] Preferably, the support legs provide stable support for the model box, ensuring that the model box will not shake or tilt during the experiment due to its own weight or experimental operations (such as water injection, water pumping, etc.), thus ensuring the stability of the experimental environment, reducing the stress concentration caused by marginal effects and asymmetry, and improving the reliability of the experimental results.

[0025] Preferably, the stop valve can control the opening and closing of the pumping pipe, and can quickly close when pumping needs to be stopped to prevent water from continuing to flow out, making it convenient for experimenters to accurately control the pumping process and the amount of water pumped. At the same time, during the experimental preparation stage or when pumping is not required, the stop valve can ensure that the pumping pipe is in a closed state to avoid external factors interfering with the experiment.

[0026] Optionally, a multi-segment sleeve pipe splicing method can be adopted, allowing the length and shape of the water pumping pipe to be flexibly adjusted according to the actual size of the model box and experimental requirements. This design improves the versatility and adaptability of the device, making it convenient for use in experiments of different scales and reducing the manufacturing and operating costs of the device. Attached Figure Description

[0027] The accompanying drawings described herein are for illustrative purposes only and do not limit the scope of this invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely schematic to aid in understanding the invention and do not specifically limit the shapes and proportions of the components. In the drawings:

[0028] Figure 1 This is a schematic diagram of a model box for a ground settlement device for simulating well flow stratified pumping as described in Example 1;

[0029] Figure 2 This is a diagram showing the stratum distribution of the ground settlement device for simulating well flow stratified pumping as described in Example 1;

[0030] Figure 3 This is a diagram showing the arrangement of the soil pressure sensor and pore pressure sensor in a ground settlement device for simulating well flow stratified pumping as described in Example 1.

[0031] Figure 4 This is a diagram showing the arrangement of displacement sensors in a ground settlement device for simulating well flow stratified pumping as described in Example 1.

[0032] Figure 5 This is a schematic diagram of the water distribution pipeline of a ground settlement device for simulating well flow stratified pumping as described in Example 1;

[0033] Figure 6 This is a schematic diagram of the sealing airbag of a ground settlement device for simulating well flow stratified pumping as described in Example 1.

[0034] Among them, 1-1, first water pump; 1-2, second water pump; 2-1, first water distribution pipe; 2-2, second water distribution pipe; 2-3, water injection hole; 2-4, water outlet hole; 3-1, first water injection pipe; 3-2, second water injection pipe; 4-1, first pressure measuring pipe; 4-2, second pressure measuring pipe; 5, outer sleeve water inlet; 6, inner sleeve; 7-1, first stop valve; 7-2, second stop valve; 8, outer sleeve; 9, sealing airbag; 10, inner sleeve water inlet; 11, support leg; 12, model box; 13, flexible connecting pipe; 14, soil pressure sensor; 15, borehole pressure sensor; 16, displacement sensor. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0036] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0037] Unless otherwise defined below, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0038] Example 1

[0039] A ground settlement device simulating well flow stratified pumping includes a model box 12, an injection pipe, a pumping pipe, a water pump, a pressure measuring pipe, an earth pressure sensor 14, and a pore pressure sensor 15. The model box 12 is cylindrical, with the pumping pipe arranged along its central axis and extending circumferentially from the outside to the inside into the injection pipe. The pumping pipe has a multi-layered casing structure, with sealing airbags 9 between the casings. The inner casing extends to a deeper sand layer, and the outer casing extends to a shallower sand layer. The pressure measuring pipe is installed within the depth range of each of the multiple sand-filled layers. Each casing of the injection pipe is connected to a water pump. The earth pressure sensor 14 and the pore pressure sensor 15 are evenly and symmetrically arranged within the model box 12. A stop valve is installed on the pumping pipe. The casing of the pumping pipe is composed of multiple sections of pipe spliced ​​together.

[0040] Specifically, such as Figure 1As shown, the model box 12 is a cylindrical model box frame structure, consisting of tempered glass sidewalls, a cage-shaped steel frame, and a waterproof bottom plate. The tempered glass sidewalls facilitate visibility of the interior, allowing for visual observation of the degree of immersion and water level. The pumping system is composed of a first stop valve 7-1, a second stop valve 7-2, a first water pump 1-1, a second water pump 1-2, a sealing airbag 9, an inner sleeve 6, and an outer sleeve 8. The inner sleeve 6 and the outer sleeve 8 are fused together. The outer sleeve 8 controls the upper aquifer, with an inlet hole 5 at the upper aquifer, and a filter screen is wrapped around the perforation. The inner sleeve 6 controls the lower aquifer, with an inlet hole 10 at the lower aquifer, and a filter screen is wrapped around the perforation. The sealing airbag 9 is located between the outer side of the inner sleeve 6 and the inner side of the outer sleeve 8, and its purpose is to prevent water from flowing from the upper layer to the lower layer.

[0041] The water injection pipe includes a water distribution pipe and a flexible connecting pipe 13. The water distribution pipe is an internally interconnected square pipe matrix. One end of the water distribution pipe is connected to the water source pipe through water injection holes 2-3, and the other end is connected to another water distribution pipe through the flexible connecting pipe 13. The water distribution pipes are symmetrically and evenly arranged in the model box 12 for immersing the sand and clay layers. Water outlet holes 2-4 are evenly arranged on the water distribution pipes.

[0042] Specifically, the first water pump 1-1 and the second water pump 1-2 use peristaltic pumps to control the extraction rate; the water injection system consists of a first water injection pipe 3-1, a second water injection pipe 3-2, a first water distribution pipe 2-1, a second water distribution pipe 2-2, and a flexible connecting pipe 13. The first water distribution pipe 2-1 and the second water distribution pipe 2-2 are a PVC square pipe matrix. The model box 12 contains an alternating layer of clay and sand, as shown in the image. Figure 2 As shown. In order to ensure uniform water infiltration and protect the formation structure from damage, water outlet holes 2-4 are drilled in the square pipe matrix, and filter screens are wrapped around the holes and connected in pairs by flexible connecting pipes 13; the side wall of the model box 12 is equipped with a first pressure measuring pipe 4-1 and a second pressure measuring pipe 4-2, which are located at the upper and lower sand layers (aquifers) respectively.

[0043] Support legs 11 are provided on the outer side of the model box 12. Specifically, the model box 12 is provided with I-shaped steel support legs 11 around its perimeter.

[0044] like Figure 3 As shown, the soil pressure sensor 14 and the pore pressure sensor 15 are arranged orthogonally and symmetrically along the central axis of the model box 12.

[0045] Example 2

[0046] The difference between this embodiment and Embodiment 1 is that:

[0047] 1) It also includes displacement sensors 16; displacement sensors 16 are evenly and symmetrically arranged inside the model box 12.

[0048] 2) The displacement sensor 16 is arranged symmetrically along the central axis of the model box 12.

[0049] like Figure 4 As shown, displacement sensors 16 are centrally symmetrically arranged in the horizontal plane along straight lines at 60° intervals, with a spacing of 30 cm. A 40 cm space is left at the top of the horizontal plane. The displacement sensors 16 can monitor the displacement changes of each point within the model box 12 in real time. The uniform and symmetrical arrangement can comprehensively reflect the spatial distribution of ground settlement, helping engineers accurately understand the deformation characteristics of the ground during stratified pumping, simulating the local soil composition and settlement mechanism, and guiding the implementation of well drilling projects.

[0050] The support leg 11 provides stable support for the model box 12, ensuring that the model box 12 will not shake or tilt due to its own weight or experimental operations (such as water injection, water pumping, etc.) during the experiment, thus ensuring the stability of the experimental environment, reducing the stress concentration caused by marginal effects and asymmetry, and improving the reliability of the experimental results.

[0051] The specific steps for using this utility model are as follows:

[0052] 1. Preparation: To prevent sand particles from entering the first water distribution pipe 2-1 and the second water distribution pipe 2-2, cover all the water outlets 2-4 of the square pipe matrix with a filter screen, and fix the sealing airbag 9, inner sleeve 6, and outer sleeve 8. The sealing airbag 9 can effectively seal the gap between the inner sleeve 6 and the outer sleeve 8, preventing water flow conversion in the aquifer.

[0053] 2. Lay the first layer (base layer) of clay, the second layer of sand, and bury the second water distribution pipes 2-2 on both sides of the second sand layer, connecting them with flexible connecting pipes 13. Lay the third layer of clay, the fourth layer of sand, bury the first water distribution pipe 2-1 of the fourth layer, and lay the fifth layer of clay, leaving a 40 cm space at the top for the placement of displacement sensors 16 and fixed pumping pipes (casing structure). The geological structure is as follows. Figure 2 As shown: Earth pressure sensor 14 and pore pressure sensor 15 are embedded in the center of each layer. Displacement sensor 16 is embedded in the top surface of the fifth layer. The embedding arrangement is as follows. Figure 3 and Figure 4 As shown.

[0054] 3. Open the valves of the first water injection pipe 3-1 and the second water injection pipe 3-2 to inject water until the soil is saturated, then let it stand. At the same time, turn on the monitoring instruments, and start pumping water when the surface displacement of the soil layer stops changing or the change is small.

[0055] 4. Start pumping. Both the first pump 1-1 and the second pump 1-2 will generate air pressure in the inner casing 6 and the outer casing 8. Therefore, when pumping water from the corresponding aquifer, the stop valve controlling the other aquifer pipe must be opened to ensure that water is only pumped out from the corresponding pipe. For pumping water from the second sand layer, open the second stop valve 7-2 to ensure that water does not flow out of the outer casing 8. At the same time, turn on the first pump 1-1 to start pumping. Since the outer casing 8 is closed and the valve is shut off, water will only flow out of the inner casing 6. The pressure head of the second layer can be observed through the corresponding first pressure measuring pipe 4-1 and second pressure measuring pipe 4-2. After the second layer is pumped out, close the second stop valve 7-2 and the first pump 1-1. For pumping water from the fourth sand layer, open the first stop valve 7-1 to ensure that water does not flow out of the inner casing. At the same time, turn on the second pump 1-2 to start pumping. Since the inner casing 6 is closed and the first stop valve 7-1 is shut off, water will only flow out of the outer casing 8. If an aquifer (clay layer and sand layer) is added, it is only necessary to extend the pumping pipe (using a multi-segment casing pipe) and seal the airbag 9.

[0056] 5. To enhance the load-bearing capacity of the model box 12, a cage-like steel support frame is constructed on the outer wall of the model box 12. To prevent excessive soil pressure on one side of the model box 12 during ground settlement, T-shaped steel support legs 11 are fabricated around the model box 12.

[0057] The above embodiments are merely one of the implementation methods for achieving the technical solution of this utility model. The scope of protection claimed by this utility model is not limited to this embodiment, but also includes any variations, substitutions, and other implementation methods that are easily conceived by those skilled in the art within the scope of the technology disclosed in this utility model. Although embodiments of this utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this utility model. The scope of this utility model is defined by the appended claims and their equivalents.

Claims

1. A ground subsidence device simulating well stream zonal pumping, characterized by, The system includes a model box, an injection pipe, a pumping pipe, a water pump, a pressure measuring pipe, a soil pressure sensor, and a pore pressure sensor. The model box is cylindrical and is filled with alternating layers of clay and sand. A pumping pipe is installed along the central axis of the model box, and the injection pipe extends into it from the outside to the inside along its circumference. The pumping pipe has a multi-layered sleeve structure, with sealing airbags between the sleeves. The inner sleeve extends to the deeper sand layer, and the outer sleeve extends to the shallower sand layer. The pressure measuring pipe is installed within the depth range of each of the multiple sand filling layers. Each sleeve of the injection pipe is connected to a water pump. Soil pressure sensors and pore pressure sensors are evenly and symmetrically arranged inside the model box.

2. The ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, The water injection pipe includes a water distribution pipe and a flexible connecting pipe; the water distribution pipe is an internally connected square pipe matrix, one end of the water distribution pipe is connected to the water source pipe through a water injection hole, and the other end is connected to another water distribution pipe through a flexible connecting pipe.

3. The ground settlement device for simulating well flow stratified pumping according to claim 2, characterized in that, The water distribution pipes are symmetrically and evenly arranged in the model box for immersing the sand and clay layers.

4. The ground settlement device for simulating well flow stratified pumping according to claim 2, characterized in that, Water outlet holes are evenly arranged on the water distribution pipe.

5. The ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, The soil pressure sensor and the pore pressure sensor are arranged orthogonally and symmetrically along the central axis of the model box.

6. The ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, It also includes displacement sensors; displacement sensors are uniformly and symmetrically arranged inside the model box.

7. A ground settlement device for simulating well flow stratified pumping according to claim 6, characterized in that, The displacement sensors are arranged symmetrically along the central axis of the model box.

8. The ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, Support legs are provided on the outside of the model box.

9. A ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, A stop valve is installed on the pumping pipe.

10. A ground settlement device for simulating well flow stratified pumping according to claim 1, characterized in that, The casing of the pumping pipe is made up of multiple sections of casing pipe spliced ​​together.

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