A model test device and method for studying deterioration characteristics of foundation soil under rainfall infiltration

Abstract

The application discloses a model test device for researching the deterioration characteristics of foundation soil under rainfall infiltration, which comprises a model box, a loading device and a rainfall device, wherein the loading device is connected with a force frame through a tension and compression sensor; a model pile is arranged in the model box, and the high end of the model pile is detachably connected with the force frame; a flowmeter is arranged on the rainfall device; and a pore water pressure gauge, a soil pressure cell and a humidity sensor are embedded in the test soil. The application has the beneficial effect that different material backfill conditions are filled in the model box, the loading device and the force frame are matched to simulate loading on the test soil, rainfall operation is carried out through the rainfall device, different foundation trench backfill conditions and rainfall infiltration processes can be simulated, and the change of the rainfall infiltration amount of the test soil in different upper foundation trenches on the foundation soil and the mutual influence between the stress field and the seepage field of the underground soil body in the rainfall process can be deeply researched.

Description

Technical Field

[0001] This invention relates to the field of underground engineering, specifically to a model test apparatus and method for studying the deterioration characteristics of foundation soil under rainfall infiltration. Background Technology

[0002] Solving the problem of precise prevention and control of urban underground engineering disasters under extreme heavy rainfall conditions is a major need, and exploring the mechanism of urban underground engineering disasters under extreme heavy rainfall conditions is also an important part of this.

[0003] Extreme heavy rainfall can trigger various disasters such as ground collapse, foundation uplift, pit collapse, and tunnel water and sand inrush. Studying the disaster mechanisms of urban underground engineering under extreme heavy rainfall conditions is an important foundation for scientifically understanding the disaster-causing laws and effectively mitigating disaster risks. Domestic and international understanding of urban underground engineering disasters under extreme heavy rainfall conditions began in the 1940s. After more than eighty years of research, relatively rich research results have been accumulated in the study of seepage damage caused by extreme heavy rainfall and its coupled disaster mechanisms.

[0004] Currently, most soil rainfall model test devices can only simulate rainfall tests on unloaded open soil surfaces. While small devices can simulate loading relatively well, they directly achieve infiltration from high to low by injecting water, which cannot effectively simulate the process of soil infiltration from a high-moisture unsaturated state to a low-moisture unsaturated state during rainfall. Furthermore, there are few current rainfall test devices that can be combined with foundation trench backfill materials for disaster theory research.

[0005] Therefore, providing a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration is a problem worthy of research. Summary of the Invention

[0006] In order to overcome the shortcomings of the existing technology, the purpose of this invention is to explore the deterioration mechanism of different soil foundations under extreme rainfall conditions, select appropriate foundation trench backfill materials, prevent underground engineering disasters, and improve economic efficiency.

[0007] The objective of this invention is achieved as follows:

[0008] A model test apparatus for studying the deterioration characteristics of foundation soil under rainfall infiltration, comprising a model box, a loading device, and a rainfall device, characterized in that:

[0009] The model box is used to fill the test soil;

[0010] The loading device is connected to a force transmission frame corresponding to the test soil in the model box via tension and compression sensors, which is used to simulate the upper load coverage of the test soil.

[0011] The model box is equipped with model piles, and the high end of the model piles is detachably connected to the force transmission frame.

[0012] The outlet of the rainfall device corresponds to the model box, and the rainfall device is equipped with a flow meter. The rainfall device is used to carry out rainfall infiltration model tests.

[0013] It also includes a pore water pressure gauge, an earth pressure cell, and a humidity sensor buried in the test soil. The tension / compression sensor, the flow meter, the pore water pressure gauge, the earth pressure cell, and the humidity sensor are electrically connected to the terminal equipment to monitor rainfall intensity and the load value on the upper part of the test soil.

[0014] In some embodiments, a base plate is connected to the bottom of the model box, and a reaction frame for fixing the loading device is slidably connected to the base plate.

[0015] In some embodiments, the reaction frame has a gate-shaped structure, with two vertical sidewalls extending downward to the base plate and slidingly engaging with the base plate, and the loading device located at the bottom of the horizontal sidewall of the reaction frame.

[0016] In some embodiments, the horizontal sidewall of the reaction frame is detachably connected to the vertical sidewall of the reaction frame, and the vertical sidewall of the reaction frame is provided with a plurality of insertion holes corresponding to the horizontal sidewall of the reaction frame.

[0017] In some embodiments, the upper part of the tension / compression sensor is connected to the bottom end of the loading device, and the bottom end of the tension / compression sensor is connected to the force transmission frame through a positioning sleeve.

[0018] In some embodiments, the system also includes a circulating water tank and a water supply tank. The rainfall device includes at least three spray pipes, the front end of which is connected to a pressure nozzle corresponding to the model box. Each set of three spray pipes is connected to one water supply pipe. A flow meter is installed on the water supply pipe to control the flow rate and volume within the water supply pipe. The bottom end of the water supply pipe is connected to a water pump located in the circulating water tank and the water supply tank.

[0019] In some embodiments, the circulating water tank includes three mutually isolated spaces distributed along its length, the connection end of the circulating drain pipe and the circulating water tank is connected to the middle space, the water pump is located in the end space of the circulating water tank, the middle space of the circulating water tank is provided with a drain pump, and the water delivery end of the drain pump guides water to the end space for water circulation through the drain pipe.

[0020] In some embodiments, the water supply tank is arranged on the front and rear sides of the model box, and the circulating water supply tank is arranged on the left and right sides of the model box.

[0021] In some embodiments, the model box is connected to an opening and closing steel plate and a steel rib latch for fixing the opening and closing steel plate, the opening and closing steel plate being movably connected to the model box.

[0022] A model test method for studying the deterioration characteristics of foundation soil under rainfall infiltration includes the following steps:

[0023] S1: Filling the lower test soil and embedding measuring elements: Fill the model box with multiple layers of test soil and compact it. After each layer of soil is compacted, roughen its surface. When the test soil is filled to the measuring point, embed the pore water pressure gauge, soil pressure cell and humidity sensor.

[0024] S2: Embedding model piles: When filling the model piles to the bearing layer, the model piles are buried in the test soil. The top of the model piles is connected to the force transmission frame. When the loading device lifts the force transmission frame to the predetermined position, the test soil is filled to the bottom of the force transmission frame. The model piles are removed, the loading device lifts the force transmission frame, and the test soil is filled until it is level with the bottom of the foundation trench.

[0025] S3: Filling the upper foundation trench backfill test soil: When the backfill soil is filled to the bottom of the foundation trench, the loading device drives the force transmission frame to move downward, connects the force transmission frame and the model pile, and fills the upper foundation trench backfill test soil to the top of the box.

[0026] S4: Loading, Rainfall and Data Monitoring: After the loading device presses down on the force transmission frame for a preset time, the rainfall device is activated. The data is monitored in real time through the pore water pressure gauge, soil pressure cell, humidity sensor, tension and compression sensor and water supply pipe, and the real-time data is observed through the terminal equipment.

[0027] S5: Data organization and test site: After the test is completed, the collected data is saved and organized.

[0028] Positive and beneficial effects:

[0029] Different backfilling conditions were filled inside the model box. The test soil was simulated by loading device and force transmission frame. Rainfall was carried out by rainfall device to simulate different foundation trench backfilling conditions and rainfall infiltration process. The study was conducted in depth on the changes in the infiltration of foundation soil by different upper foundation trench backfill test soil during rainfall, as well as the mutual influence between the stress field and seepage field of underground soil.

[0030] This study has significant scientific research value and economic benefits for investigating the principle of bearing capacity change in foundation soil caused by fluid-structure interaction under rainfall conditions and for exploring suitable backfill materials for foundation trenches.

[0031] The device uses a pore water pressure gauge, soil pressure cell, and humidity sensor in the test soil to monitor soil infiltration, soil pressure, and soil humidity in real time, making the monitoring of changes in foundation soil infiltration and rainfall infiltration process more accurate.

[0032] In a preferred embodiment, the drainage hole, circulating drainage pipe, and circulating water tank can be used to collect and recycle the seepage water inside the model box, thus saving more test water.

[0033] Model tests were conducted on the deterioration of foundation soil under multiple rainfall infiltration conditions based on different backfill materials for foundation trenches. In the model tests, the soil in the model box was loaded, rainfall was applied, and the pore water pressure, soil pressure, and humidity of the soil at different locations were measured to analyze their variation patterns. This study plays a very important role in the research on the coupled disaster mechanism of foundation soil under rainfall conditions. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the experimental apparatus of the present invention;

[0035] Figure 2 This is a rear view schematic diagram of the model box in the experimental device of the present invention;

[0036] Figure 3 This is a schematic diagram of the cross-sectional installation structure of the force transmission frame in the test device of the present invention;

[0037] Figure 4 This is a schematic diagram of the rainfall device in the experimental apparatus of the present invention;

[0038] Figure 5 This is a schematic diagram of the steps of the test method of the present invention;

[0039] The diagram shows: 1. Reaction frame; 2. Loading device; 3. Force transmission frame; 4. Rainfall device; 5. Flow meter; 6. Water supply pipe; 7. Model box; 8. Steel rib; 9. Opening and closing steel plate; 10. Steel rib latch; 11. Circulating water supply tank; 12. Water supply tank; 13. Circulating drainage pipe; 14. Base plate; 15. Drain hole; 16. Model pile; 17. Transparent acrylic plate; 18. Tension and compression sensor; 19. Positioning sleeve; 20. Drainage pipe; 21. Water pump; 22. Drainage pump; 23. Pressure nozzle. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] See Figures 1-5As shown, the present invention provides a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration, including a model box 7, a loading device 2, and a rainfall device 4. The model box 7 has a length, width, and height of 1000mm × 1000mm × 1500mm and is used to fill the test soil. Angle steel of 100mm × 100mm × 10mm is welded around the model box 7 to increase the support strength of the model box 7. The loading device 2 is located above the model box 7. When the loading device 2 is installed, the bottom of the model box 7 is provided with a base plate 14, which is a steel plate with a thickness of 20mm. A reaction frame 1 is installed on the surface of the base plate 14. The reaction frame 1 has a door-shaped structure. During installation, the two vertical side walls of the reaction frame 1 are located on both sides of the model box 7, and its bottom end is connected to the base plate 14 through a slide rail. The bottom surface of the horizontal side wall of the reaction frame 1 is connected to the loading device 2. During connection, it can be connected to the top of the loading device 2 by snap-fit ​​or bolt connection.

[0042] The loading device 2 can be loaded by a pneumatic cylinder, a hydraulic cylinder, or an electric telescopic rod. Its telescopic end faces downward and is connected to a tension / compression sensor 18 by bolts. The upper part of the force transmission frame 3 has an open structure. The tension / compression sensor 18 is located inside the force transmission frame 3. The distance from the top of the model box 7 to the top plate of the reaction frame 1 is greater than the height of the force transmission frame 3 to facilitate the positioning of the force transmission frame 3. In specific installation, the upper part of the tension / compression sensor 18 is connected to the loading device 2 by bolts, and the lower part of the tension / compression sensor 18 is connected to the positioning sleeve 19. The lower end of the positioning sleeve 19 can be connected to the force transmission frame 3 and the lower model pile 16 by a flange. The flange is fixed by bolts, thereby realizing the detachable connection between the force transmission frame 3 and the model pile 16.

[0043] The bottom of the tension / compression sensor 18 is connected to the inner bottom surface of the force transmission frame 3 via a positioning sleeve 19. The bottom of the force transmission frame 3 has bolt holes. The bottom of the force transmission frame 3 is detachably connected to the model pile 16 via a flange. The model pile 16 extends vertically downward into the interior of the model box 7, which can serve the purpose of vertical positioning. The force transmission frame 3 can compact the test soil inside the model box 7 to simulate the upper load coverage of the test soil.

[0044] Rainfall devices 4 are provided around the top of the model box 7. Each rainfall device 4 includes at least three spray pipes. The front end of each spray pipe is connected to a pressure nozzle 23 corresponding to the model box 7. Each three spray pipes are connected to a water supply pipe 6. A flow meter 5 is installed on the water supply pipe 6 to control the flow rate and flow rate in the water supply pipe 6. The bottom end of the water supply pipe 6 is connected to a water pump 21 located in the water supply tank 12. The outlet of the rainfall device 4 corresponds to the model box 7, and the rainfall device 4 is equipped with a flow meter 5. The rainfall device 4 is used to carry out rainfall infiltration model tests.

[0045] In the specific arrangement, six spray pipes are arranged on each side of the model box 7. The front end of the spray pipe is connected to the pressure nozzle 23. The pressure nozzle 23 corresponds to the opening of the model box 7. The end of every three spray pipes is connected to a water supply pipe 6. The water supply pipe 6 is a medium soft plastic pipe with an outer diameter of 6mm. The flow meter 5 is installed on the water supply pipe 6 to control the flow rate of the water supplied in the water supply pipe 6. The bottom end of the water supply pipe 6 is connected to the water delivery end of the water pump 21. The water pump 21 can pump the water from the circulating water tank 11 and the water tank 12 to different water supply pipes 6. The water can be discharged into the model box 7 through the pressure nozzle 23 at the front end of the spray pipe.

[0046] The circulating water tanks 11 and 12 have dimensions of 400mm × 150mm × 300mm. During installation, water tank 12 is positioned at the front and rear of the model box 7, while circulating water tank 11 is positioned on the left and right sides of the model box 7. This means that circulating water tank 11 corresponds to the two vertical side walls of the reaction frame 1. Multiple drainage holes 15, each 1cm in diameter, are threaded through the side walls of the model box 7 corresponding to the circulating water tank 11. There can be three drainage holes 15 located near the bottom of the model box 7. The interior of the model box 7 is covered with filter paper and wire mesh covering the drainage holes 15. A circulating drain pipe 13, connected to the circulating water tank 11, is connected to the outer wall of the model box 7. The internal parts of the circulating water tank 11 and the model box 7 are connected through the drainage holes 15. Furthermore… The circulating drain pipe 13 is inclined and its lower end is connected to the circulating water supply tank 11 to facilitate the drainage of water from the model box 7 into the circulating water supply tank 11. The circulating water supply tank 11 is equipped with two partitions along its length, which divide the interior into three spaces. The connection end of the circulating drain pipe 13 to the circulating water supply tank 11 corresponds to the middle space. After the water in the model box 7 is filtered by filter paper and wire mesh, it flows into the middle of the circulating water supply tank 11 through the circulating drain pipe 13. A drain pump 22 is installed in the middle space of the circulating water supply tank 11. The water delivery end of the drain pump 22 is connected to the drain pipe 20. When the drain pump 22 is working, it can pump the water in the middle space of the circulating water supply tank 11 to the edge space of the circulating water supply tank 11, and then pump it into the water supply pipe 6 by the water pump 21, thereby supplying water to the rain device 4.

[0047] It also includes a pore water pressure gauge, an earth pressure cell, and a humidity sensor buried inside the lower test soil. The tension-compression sensor 18, the flow meter 5, the pore water pressure gauge, the earth pressure cell, and the humidity sensor are electrically connected to the terminal equipment. The terminal equipment can be a computer terminal, a mobile device terminal, or other terminal receiving device. The terminal equipment includes at least a display screen, through which the data monitored by the tension-compression sensor 18, the flow meter 5, the pore water pressure gauge, the earth pressure cell, and the humidity sensor can be displayed and viewed.

[0048] In a preferred embodiment, the opening and closing steel plate 9 is located in the middle of the model box 7. The opening and closing steel plate 9 has a length, width, and thickness of 1000mm × 500mm × 10mm. The surface opposite to the opening and closing steel plate 9 is provided with a transparent acrylic plate 17 with a thickness of 10mm on the opposite side, which allows observation of the interior of the model box 7 through the transparent acrylic plate 17. On both sides of the opening and closing steel plate 9, the wall thickness of the model box 7 is 10mm and it is an integral fixed steel plate. Multiple steel ribs 8 are distributed on the side of the model box 7 along the horizontal and vertical directions to improve the support strength of the model box 7. There can be three steel ribs 8.

[0049] In the specific connection, the opening and closing steel plate 9 is connected to the model box 7 via a hinge. A steel rib 8 latch is detachably installed on the outside of the model box 7. The steel rib 8 latch is used to limit the opening and closing steel plate 9. In use, after the opening and closing steel plate 9 is rotated to correspond with the opening on the model box 7, the steel rib 8 latch has a strip-shaped structure. Its two ends are fixed to the outside of the model box 7 by bolts. Alternatively, the two ends of the steel rib 8 latch can be connected and fixed to the steel rib 8 on the model box 7 by bolts. The opening and closing steel plate 9 is limited by the steel rib 8 latch. The side of the model box 7 corresponding to the opening and closing steel plate 9 is a transparent acrylic plate 17, which is detachably connected to the model box 7.

[0050] In a preferred embodiment, the horizontal sidewall of the reaction frame 1 is detachably connected to the vertical sidewall of the reaction frame 1. The vertical sidewall of the reaction frame 1 is provided with multiple insertion holes, which are evenly distributed along the height direction of the vertical sidewall of the reaction frame 1. The horizontal sidewall section of the reaction frame 1 is connected to the insertion holes. Adjusting the insertion position of the horizontal sidewall of the reaction frame 1 can adjust the height of the loading device 2, thereby adapting to soil tests at greater heights and having a wide range of applications.

[0051] like Figure 5 As shown, a model test apparatus for studying the deterioration characteristics of foundation soil under rainfall infiltration includes the following steps:

[0052] S1: Filling the lower test soil and embedding measuring elements: Fill the model box 7 with multiple layers of test soil and compact it. After each layer of soil is compacted, its surface is roughened. When the test soil is filled to the measuring point, embed the pore water pressure gauge, soil pressure cell and humidity sensor.

[0053] S2: Installing model piles: When filling model piles 16 into the bearing layer, bury model piles 16 into the test soil. The top of model piles 16 is connected to the force transmission frame 3. When the loading device 2 lifts the force transmission frame 3 to the predetermined position, fill the test soil to the bottom of the force transmission frame 3, remove model piles 16, lift the force transmission frame 3 with the loading device 2, and continue to fill the test soil until it is level with the bottom of the foundation trench.

[0054] S3: Filling the upper foundation trench backfill test soil: When the backfill soil is filled to the bottom of the foundation trench, the loading device 2 drives the force transmission frame 3 to move downward, connects the force transmission frame 3 and the model pile 16, and fills the upper foundation trench backfill test soil to the top of the box.

[0055] S4: Loading, rainfall and data monitoring: After the loading device 2 presses down on the force transmission frame 3 for a preset time, the rainfall device 4 is turned on. The data is monitored in real time through the pore water pressure gauge, soil pressure box, humidity sensor, tension and compression sensor 18 and water supply pipe 6, and the real-time data is observed through the terminal equipment.

[0056] S5: Data organization and test site: After the test is completed, the collected data is saved and organized.

[0057] In practice, before the test begins, waterproof and seal the model box 7, apply paint and rust inhibitor to the surface of the model box 7, cover the steel plate joints with aluminum foil tape, and then apply a layer of sealant. After it solidifies, the test can begin.

[0058] Open the hinged steel plate 9, mark the scale lines every 5cm inside the model box 7, fill the lower test soil powder into the model box 7 every 5cm and compact it. After each layer of soil is compacted, roughen the surface. When filling to the measurement point, embed the pore water pressure gauge, soil pressure box and humidity sensor. Use waterproof tape to stick the connection of the measuring element wires. After the measuring element wires are bent and run to the inner wall of the model box 7, cover them with waterproof tape. Lead them up along the box wall of the model box 7 to connect to the CM-2B static resistance strain gauge. When the lower test soil powder in the box is filled to the lower part of the hinged steel plate 9, close the hinged steel plate 9, tighten the bolts and insert the steel rib 8 latch to fix the hinged steel plate 9.

[0059] In this embodiment, aluminum pipe piles are used for model pile 16. When filling to the bearing layer of model pile 16, model pile 16 is buried. The top of model pile 16 is connected to force transmission frame 3 to ensure verticality. Loading device 2 is connected to force transmission frame 3 and lifted to ensure verticality. Force transmission frame 3 is lifted to a predetermined position. Except for the bottom, the surrounding area is the foundation trench space. When filling to the bottom of force transmission frame 3, model pile 16 and force transmission frame 3 are removed. The force transmission device is lifted by loading device 2 and filling continues until the bottom of the foundation trench is level.

[0060] When the test soil is filled to the bottom of the foundation trench, the force transmission frame 3 is lowered and connected to the model pile 16 through the loading device 2. The test soil for the upper foundation trench backfill is then filled to 3-10cm from the top of the box, preferably 5cm. In this embodiment, the test soil for the upper foundation trench backfill can be geopolymer solidified soil.

[0061] After all the test soil is filled, the loading device 2 presses down the force transmission frame 3 for a preset time, which can be 15-50 minutes, preferably 30 minutes or 35 minutes. The rain device 4 is placed around the top of the model box 7 and fixed with tape. The rain device 4 is turned on. In this embodiment, an electromagnetic flow meter 5 is connected to the water supply pipe 6, and a water pump 21 with a rated power of 1000W is connected to the bottom. In this embodiment, a drainage pump 22 with a rated power of 200W is used. The drain hole 15 at the bottom of the model box 7 is connected to the circulating water supply tank 11 by the circulating drainage pipe 13. In this embodiment, the circulating drainage pipe 13 is a transparent silicone hose.

[0062] In this embodiment, the loading device 2 uses a hydraulic cylinder for loading. The tension / compression sensor 18 is connected and installed to the loading device 2 by bolts. In this embodiment, the tension / compression sensor 18 is an S-type tension / compression sensor with a range of 3t. The wires are connected to the matching reading instrument. The loading device 2 and the rainfall device 4 are started synchronously. The display instrument matching the tension / compression sensor 18 reads the simulated upper load weight. The static resistance strain gauge collects pore water pressure, soil pressure, and humidity sensor data. The terminal equipment includes at least one display to display the monitoring results. The data is monitored in real time through the pore water pressure gauge, soil pressure cell, humidity sensor, tension / compression sensor 18, and water supply pipe 6. The real-time data is observed through the terminal equipment.

[0063] After the experiment, the data should be organized to facilitate subsequent data analysis. The experimental site should be tidied up to prepare for the next experiment.

[0064] The above content is only for illustrating the technical concept of the present invention and cannot limit the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in the present invention shall fall within the scope of protection of the claims of the present invention.

Claims

1. A test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration, characterized in that, The device includes a model box (7), a loading device (2), and a rainfall device (4), wherein the model box (7) is used to fill the test soil; The loading device (2) is connected to a force transmission frame (3) corresponding to the test soil in the model box (7) via a tension and compression sensor (18) to simulate the upper load covering of the test soil; The model box (7) is equipped with a model pile (16), and the high end of the model pile (16) is detachably connected to the force transmission frame (3); The outlet of the rainfall device (4) corresponds to the model box (7), and the rainfall device (4) is equipped with a flow meter (5). The rainfall device (4) is used to carry out rainfall infiltration model tests. It also includes a pore water pressure gauge, a soil pressure cell, and a humidity sensor buried in the test soil. The tension and compression sensor (18), the flow meter (5), the pore water pressure gauge, the soil pressure cell, and the humidity sensor are electrically connected to the terminal equipment to monitor the rainfall intensity and the load value on the upper part of the test soil. The method includes the following steps: S1: Fill the lower test soil and bury the measuring elements: Fill the model box (7) with multiple layers of test soil and compact it. After each layer of soil is compacted, roughen its surface. When the test soil is filled to the measuring point, bury the pore water pressure gauge, soil pressure box and humidity sensor. S2: Embedding model piles: When filling to the bearing layer, embed the model pile (16). The top of the model pile (16) is connected to the force transmission frame (3). When the loading device (2) lifts the force transmission frame (3) to the predetermined position, fill the test soil to the bottom of the force transmission frame (3), disconnect the connection between the force transmission frame (3) and the model pile (16), lift the force transmission frame (3) with the loading device (2), and continue to fill the test soil until it is level with the bottom of the foundation trench. S3: Filling test soil: When filling the soil to the bottom of the foundation trench, the loading device (2) drives the force transmission frame (3) to move downward, connects the force transmission frame (3) and the model pile (16), and fills the test soil to the top of the box; S4: Loading, rainfall and data monitoring: After the loading device (2) presses down the force transmission frame (3) for a preset time, the rainfall device (4) is turned on. The data is monitored in real time through the pore water pressure gauge, soil pressure box, humidity sensor and tension-compression sensor (18), and the real-time data is observed through the terminal equipment. S5: Data processing and test site management: After the test is completed, the collected data is saved and processed.

2. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 1, characterized in that: Includes a base plate (14) connected to the bottom of the model box (7), on which a reaction frame (1) for fixing the loading device (2) is slidably connected.

3. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 2, characterized in that: The reaction frame (1) has a gate-shaped structure. The two vertical sidewalls of the reaction frame (1) extend downward to the base plate (14) and slide in cooperation with the base plate (14). The loading device (2) is located at the bottom of the horizontal sidewall of the reaction frame (1).

4. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 3, characterized in that: The horizontal sidewall of the reaction frame (1) is detachably connected to the vertical sidewall of the reaction frame (1), and the vertical sidewall of the reaction frame (1) is provided with a plurality of insertion holes corresponding to the horizontal sidewall of the reaction frame (1).

5. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 1 or 2, characterized in that: The upper part of the tension / compression sensor (18) is connected to the bottom end of the loading device (2), and the bottom end of the tension / compression sensor (18) is connected to the force transmission frame (3) through the positioning sleeve (19).

6. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 1 or 2, characterized in that: It also includes a circulating water tank (11) and a water tank (12). The rainfall device (4) includes no less than three spray pipes, and the front end of the spray pipes is connected to a pressure nozzle (23) corresponding to the model box (7). Among them, every three spray pipes are connected to a water supply pipe (6), and the flow meter (5) is installed on the water supply pipe (6) to control the flow rate and flow rate in the water supply pipe (6); The bottom end of the water supply pipe (6) is connected to a water pump (21) located in the circulating water tank (11) and the water supply tank (12).

7. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 6, characterized in that: The circulating water tank (11) includes three mutually isolated spaces distributed along its length. The connection end of the circulating drain pipe (13) and the circulating water tank (11) is connected to the middle space. The water pump (21) is located in the end space of the circulating water tank (11). The middle space of the circulating water tank (11) is equipped with a drain pump (22). The water delivery end of the drain pump (22) guides water to the end space for water circulation through the drain pipe (20).

8. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 6, characterized in that: The water supply tank (12) is arranged on the front and rear sides of the model box (7), and the circulating water supply tank (11) is arranged on the left and right sides of the model box (7).

9. The test method for a model test device for studying the deterioration characteristics of foundation soil under rainfall infiltration as described in claim 1 or 2, characterized in that: The model box (7) is connected to an opening and closing steel plate (9) and a steel rib (8) latch that fixes the opening and closing steel plate (9). The opening and closing steel plate (9) is movably connected to the model box (7).

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