A test device and method for simulating seepage erosion of soil-rock mixture under cyclic water action

Abstract

The application discloses a kind of test device and method for simulating seepage erosion of soil-rock mixture under cyclic hydraulic action, and the device includes water head control system, cyclic hydraulic action seepage device, soil-water collection system and data acquisition and control system;Method is, cyclic hydraulic action seepage device fills sample and observes erosion phenomenon, monitors local hydraulic gradient in test;Soil-water collection system monitors cumulative erosion amount of fine particles and collects erosion fine particles, total seepage water amount;Data acquisition and control system collect local water pressure of sample, erosion particle concentration and seepage water amount, calculate local hydraulic gradient of corresponding section, calculate cumulative erosion fine particle mass according to turbidity value and seepage water mass increment, calculate average seepage velocity according to seepage water volume increment in unit time and cross-sectional area of soil-rock mixture sample, and control the size and application direction of applied water head.The application reflects the seepage erosion process of soil-rock mixture under cyclic hydraulic action, and makes up for the deficiency that traditional test is difficult to simulate reciprocating hydraulic condition.

Description

Technical Field

[0001] This invention relates to the field of laboratory testing for seepage erosion of soil-rock mixtures, and more particularly to a test apparatus and method for simulating seepage erosion of soil-rock mixtures under the action of circulating hydraulics. Background Technology

[0002] Soil-rock mixtures are highly heterogeneous, loose media composed of boulders, soil, and pores, widely distributed in landslide deposits, hydropower project overburden, road slopes, and reservoir bank deposits. Under the influence of groundwater seepage, reservoir water level fluctuations, rainfall infiltration, and reciprocating hydraulic disturbances, the fine particles within these mixtures are easily activated, migrated, and lost, leading to changes in pore structure, evolution of permeability, and localized damage expansion. In severe cases, this can induce slope instability. Therefore, conducting seepage erosion tests on soil-rock mixtures under circulating hydraulic action is of great significance for revealing their erosion mechanisms, evolution of permeability characteristics, and failure criteria.

[0003] Existing seepage erosion tests are mostly conducted on homogeneous soils, sandy soils, or single-particle media, typically using constant unidirectional seepage conditions. While these tests can reflect general particle loss and seepage deformation phenomena, they are difficult to realistically simulate the complex response of soil-rock mixtures under circulating hydraulic action. Especially in actual engineering, the seepage direction and hydraulic gradient often change repeatedly with variations in external hydraulic conditions. The local water pressure, local hydraulic gradient, and fine-particle erosion process within the sample all exhibit significant time-varying and spatial differences, and traditional devices struggle to effectively simulate and continuously monitor such processes.

[0004] Currently, the apparatus used for seepage erosion tests has the following problems: ① Most conventional seepage erosion test apparatuses adopt a unidirectional constant seepage method, which is difficult to simulate the circulating hydraulic action of seepage direction changing repeatedly in actual engineering, and is not suitable for the erosion response of soil-rock mixtures under complex hydraulic conditions; ② Conventional apparatuses have limited precision in adjusting and controlling water head and hydraulic gradient, and mostly focus on observing the overall seepage phenomenon, lacking real-time monitoring means for local water pressure and local hydraulic gradient inside the sample, making it difficult to reflect the local evolution characteristics in the seepage erosion process; ③ Existing technologies mostly use discrete methods of collecting, drying, and weighing after the test to measure eroded fine particles, which makes it difficult to achieve continuous quantitative monitoring of erosion and is not conducive to identifying the moment of erosion change and its correspondence with seepage response; ④ Some test apparatuses have low levels of visualization and automation, making it difficult to meet the needs of intuitive observation of erosion phenomena, research on erosion of fine particles of different sizes, and long-term continuous testing. Summary of the Invention

[0005] Purpose of the Invention: To address the problems existing in the background technology, this invention proposes an experimental device and method for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action. This device and method can adjust the height of a constant head water supply tank via an electric guide rail, achieving stable, continuous, and controllable application of the water head. It automatically switches the seepage direction using an electric three-way ball valve and upper and lower outlet ball valves, simulating the reciprocating hydraulic conditions in actual engineering projects. The seepage chamber is made of transparent acrylic material to facilitate observation of the evolution of seepage channels, fine particle migration, and local erosion damage phenomena under circulating hydraulic action. Evenly spaced water pressure sensors can acquire real-time changes in internal local water pressure. The combination of a turbidity probe and a weighing device enables continuous monitoring of the cumulative loss of eroded fine particles and the amount of seepage water. This invention realistically reflects the seepage erosion process of soil-rock mixtures under circulating hydraulic action, overcoming the shortcomings of traditional experiments in simulating reciprocating hydraulic conditions. It achieves simultaneous monitoring of erosion development, seepage response, and fine particle loss, which is beneficial for deeply revealing the seepage erosion mechanism of soil-rock mixtures and providing a basis for related engineering prevention and control.

[0006] Technical solution: To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This invention relates to an experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action. The apparatus includes a head control system, a circulating hydraulic seepage device, a soil-water collection system, and a data acquisition and control system. The head control system comprises an electric guide rail, a constant head water supply tank, a water storage tank, and a water pump. It is used to raise the constant head water supply tank to a specified height according to experimental needs, providing a constant head of hydraulic force to the soil-rock mixture sample. The circulating hydraulic seepage device includes a seepage chamber, a soil-rock mixture sample, a water pressure sensor, and an electric three-way ball valve. It is used to fill the soil-rock mixture sample and apply circulating hydraulic force, monitoring the local hydraulic gradient of the sample in real time during the experiment. A transparent acrylic material allows observation of the seepage erosion phenomenon of the soil-rock mixture sample under circulating hydraulic action.

[0008] The soil-water collection system includes a particle collection tank, a turbidity probe, a filter screen, a water collection tank, and a weighing device. It is used to monitor the cumulative erosion of fine particles in real time and collect eroded fine particles for subsequent research on the gradation of these particles. It also collects the total amount of seepage water to calculate the permeability coefficient of the soil-rock mixture sample during erosion. The data acquisition and control system includes a computer used to acquire local water pressure, eroded particle concentration, and seepage volume of the sample in real time. It calculates the local hydraulic gradient of the corresponding section based on pore water pressure measured by adjacent water pressure sensors, the elevation of the measuring points, and the distance between the measuring points. It calculates the cumulative mass of eroded fine particles based on the turbidity value measured by the turbidity probe and the mass increment of seepage water measured by the weighing device. It calculates the average seepage velocity based on the volume increment of seepage water per unit time and the cross-sectional area of ​​the soil-rock mixture sample. Simultaneously, it controls the applied water head and automatically adjusts the direction of hydraulic action.

[0009] The electric guide rail of the head control system consists of a slider platform, a lower limit switch, and an upper limit switch. The slider platform is used to lift the constant head water supply tank. The lower limit switch and the upper limit switch are used to limit the vertical height of the slider platform to prevent the constant head water supply tank from falling to the lower limit of the required height under the action of gravity.

[0010] The constant head water supply tank consists of a guide plate, an overflow trough, an inlet, an overflow outlet, and an outlet. The guide plate is inserted obliquely into the constant head water supply tank to guide excess water to the overflow trough, and then flows back to the storage tank through the overflow outlet, thereby realizing the recycling of excess water and saving water.

[0011] The constant head water supply tank uses a water pump to deliver water from the storage tank to the supply tank through the inlet, always maintaining the highest water level, and provides a constant head effect to the circulating hydraulic seepage device, including the seepage chamber, through the outlet.

[0012] The seepage chamber consists of an upper outlet trough, a lower outlet trough, a gravel cushion layer, a water pressure sensor, an upper inlet, a lower inlet, an acrylic filter plate, and a waterproof gasket. The entire seepage chamber is made of transparent acrylic material and is used to observe the seepage erosion phenomenon of soil-rock mixture samples under the action of circulating water. A waterproof gasket is placed between the upper outlet trough, the lower outlet trough, and the gravel cushion layer to prevent water from seeping out.

[0013] An acrylic filter plate and a waterproof gasket are placed between the upper outlet tank and the seepage chamber, and an acrylic filter plate and a waterproof gasket are placed between the lower outlet tank and the seepage chamber to control the particle size of the seepage erosion particles. By replacing acrylic filter plates of different sizes, the seepage erosion mechanism under different erosive fine particle sizes can be studied. Water pressure sensors are arranged at the same height intervals on the seepage chamber to measure the local hydraulic gradient of the soil-rock mixture sample in real time.

[0014] The seepage chamber is connected to the water head control system and the soil water collection system via an electric three-way ball valve, an upper outlet electric ball valve, and a lower outlet electric ball valve. It is controlled by a data acquisition and control system to adjust the water flow direction in the seepage chamber.

[0015] The filter screen is used to completely block the corrosive fine particles in the particle collection pool; the turbidity probe measures the concentration of corrosive fine particles in the particle collection pool, and the data acquisition and control system calculates and records the total mass of corrosive fine particles in the current particle collection pool in real time.

[0016] The present invention provides an experimental method for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action, comprising the following steps:

[0017] 1) Construct an indoor test apparatus to simulate seepage erosion of soil-rock mixtures under circulating hydraulic action. Turn on the water pressure sensor, turbidity probe, and weighing device, and debug the computer, performing zeroing and calibration.

[0018] 2) Turn on the electric guide rail and adjust the liquid level of the constant head water supply tank to be level with the top of the seepage chamber. At this time, the hydraulic gradient in the seepage chamber is 0. Turn on the water pump to send the water in the storage tank to the constant head water supply tank. The overflowing water flows back to the storage tank along the guide plate and overflow channel.

[0019] 3) Open the automatic control electric three-way ball valve and the upper outlet electric ball valve to allow water to flow from bottom to top through the seepage chamber until the air in the seepage chamber is exhausted; control the electric three-way ball valve, the upper outlet electric ball valve and the lower outlet electric ball valve to control the seepage direction and change the seepage direction in the seepage chamber at set intervals.

[0020] 4) Turn on the water pressure sensor, turbidity probe and weighing device, and transmit the measured data to the computer in real time to start continuously recording the local water pressure in the seepage chamber, the particle concentration in the particle collection tank and the amount of seepage in the collection tank.

[0021] 5) Calculate based on the pore water pressure measured by each water pressure sensor. Total head at corresponding measuring points:

[0022]

[0023] And calculate the first based on the total head difference and spacing between adjacent water pressure sensors. Local hydraulic gradient of each monitoring section :

[0024]

[0025] in, The water head at the corresponding measuring point. Let g be the density of water and g be the acceleration due to gravity. The distance between the ringing water pressure sensors; based on the mass increment at adjacent sampling times of the weighing device. Calculate the average seepage velocity inside the soil-rock mixture sample and permeability coefficient :

[0026]

[0027]

[0028] in, Let be the cross-sectional area of ​​the soil-rock mixture sample, and i be the total hydraulic gradient applied to the soil-rock mixture sample; based on the mass concentration of eroded fine particles output by the turbidity probe. Calculate the cumulative amount of eroded fine particles :

[0029]

[0030] in, It represents the increase in the volume of seepage water per unit time; when the cumulative amount of eroded fine particles or the average seepage velocity changes abruptly, the corresponding time is recorded and it is indicated that the sample is undergoing erosion and damage.

[0031] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0032] (1) The device and method of the present invention realize the automatic periodic switching of the seepage direction, and more realistically simulate the circulating hydraulic action of soil-rock mixture in actual engineering.

[0033] (2) By adjusting the height of the constant head water supply tank, the water head size is precisely controlled, thereby achieving stable, continuous and controllable hydraulic gradient loading.

[0034] (3) By installing water pressure sensors along the flow chamber, the local water pressure changes inside the sample can be obtained in real time and the local hydraulic gradient can be calculated.

[0035] (4) By utilizing the turbidity probe, filter screen and weighing device, the cumulative loss of erosion fine particles and the amount of seepage water can be continuously monitored, thereby improving the quantitative analysis capability of the erosion process.

[0036] (5) It has both transparent and visual observation and automated data acquisition and control functions, which can intuitively reveal the evolution process of seepage erosion and improve experimental efficiency and research applicability. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the experimental device for simulating seepage erosion of soil-rock mixtures under the action of circulating hydraulics, as per the present invention.

[0038] Figure 2 This is a three-dimensional schematic diagram of the circulating hydraulic seepage device used in the experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to the present invention.

[0039] Figure 3 This is a three-dimensional schematic diagram of the constant head water supply tank used in the experimental device for simulating seepage erosion of soil-rock mixture under circulating hydraulic action according to the present invention.

[0040] Figure 4 This diagram illustrates the data processing procedure for cyclic seepage erosion of soil-rock mixtures, which is used in the experimental apparatus of this invention to simulate seepage erosion of soil-rock mixtures under cyclic hydraulic action. Detailed Implementation

[0041] Figures 1 to 3In the middle: 1-Electric guide rail, 2-Slider platform, 3-Lower limiter, 4-Upper limiter, 5-Constant head water supply tank, 6-Guide plate, 7-Overflow trough, 8-Water storage tank, 9-Water pump, 10-Inlet, 11-Overflow port, 12-Outlet, 13-Electric three-way ball valve, 14-Seepage chamber, 15-Soil-rock mixture sample, 16-Upper outlet trough, 17-Lower outlet trough, 18-Gravel cushion layer, 19-Water pressure sensor, 20-Upper inlet, 21-Lower inlet, 22-Upper outlet electric ball valve, 23-Lower outlet electric ball valve, 24-Particle collection tank, 25-Turbidity probe, 26-Filter screen, 27-Collection tank, 28-Weighing device, 29-Computer, 30-Acrylic filter plate, 31-Waterproof gasket.

[0042] This invention relates to an experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action, comprising a head control system, a circulating hydraulic seepage device, a soil-water collection system, and a data acquisition and control system, wherein:

[0043] The head control system includes an electric guide rail 1, a constant head water supply tank 5, a water storage tank 8, and a water pump 9. The head control system raises the constant head water supply tank 5 to a specified height according to experimental needs, providing a constant head of hydraulic force to the soil-rock mixture sample 15. The electric guide rail 1 consists of a slider platform 2, a lower limit switch 3, and an upper limit switch 4. The slider platform 2 is used to raise the constant head water supply tank 5. The lower limit switch 3 and the upper limit switch 4 are used to limit the vertical height of the slider platform 2, preventing the constant head water supply tank 5 from descending to the required lower limit under gravity.

[0044] The constant head water supply tank 5 consists of a guide plate 6, an overflow trough 7, an inlet 10, an overflow outlet 11, and an outlet 12. The guide plate 6 is inserted obliquely into the constant head water supply tank 5 to guide excess water to the overflow trough 7, and then flows back to the storage tank 8 through the overflow outlet 11, thereby realizing the recycling of excess water and saving water. Water from the storage tank 8 is pumped by the water pump 9 to the constant head water supply tank 5 through the inlet 10, always maintaining the highest water level, and providing a constant head effect to the circulating hydraulic seepage device, including the seepage chamber 14, through the outlet 12.

[0045] The circulating hydraulic seepage device includes a seepage chamber 14, a soil-rock mixture sample 15, a water pressure sensor 19, and an electric three-way ball valve 13. It is used to fill the soil-rock mixture sample 15 and apply circulating hydraulic action, monitoring the local hydraulic gradient of the sample in real time during the test. The transparent acrylic material allows observation of the seepage erosion phenomenon of the soil-rock mixture sample 15 under circulating hydraulic action. The seepage chamber 14 consists of an upper outlet trough 16, a lower outlet trough 17, a gravel cushion layer 18, a water pressure sensor 19, an upper inlet 20, a lower inlet 21, an acrylic filter plate 30, and a waterproof gasket 31. The entire seepage chamber 14 is made of transparent acrylic material for observing the seepage erosion phenomenon of the soil-rock mixture sample under circulating hydraulic action. The upper outlet trough 16 is connected to the gravel cushion layer 18, and the lower outlet... A waterproof gasket 31 is placed between the water tank 17 and the gravel cushion layer 18 to prevent water seepage. Acrylic filter plates 30 and waterproof gaskets 31 are placed between the upper water outlet tank 16 and the seepage chamber 14, and between the lower water outlet tank 17 and the seepage chamber 14, to control the particle size of seepage erosion. Different sizes of acrylic filter plates 30 can be replaced to study the seepage erosion mechanism under different erosive fine particle sizes. Water pressure sensors 19 are arranged at the same height intervals on the seepage chamber 14 to measure the local hydraulic gradient of the soil-rock mixture sample in real time. The seepage chamber 14 is connected to the water head control system and the soil-water collection system through an electric three-way ball valve 13, an upper water outlet electric ball valve 22, and a lower water outlet electric ball valve 23. The data acquisition and control system controls the flow direction of the water in the seepage chamber 14.

[0046] The soil and water collection system includes a particle collection tank 24, a turbidity probe 25, a filter screen 26, a water collection tank 27, and a weighing device 28. It is used to monitor the cumulative erosion of fine particles in real time and collect the eroded fine particles for subsequent research on the gradation law of the eroded fine particles, and to collect the total amount of seepage water to calculate the permeability coefficient of the soil-rock mixture sample during the erosion process. The filter screen 26 is used to completely block the eroded fine particles in the particle collection tank 24. The turbidity probe 25 measures the fine particle concentration of the eroded fine particles in the particle collection tank 24, and calculates and records the total mass of the cumulative eroded fine particles in the particle collection tank 24 in real time through the data acquisition and control system.

[0047] The data acquisition and control system includes a computer 29, which is used to acquire local water pressure, erosion particle concentration and seepage volume of the sample in real time. It calculates the local hydraulic gradient of the corresponding section based on the pore water pressure, measuring point elevation and measuring point spacing measured by adjacent water pressure sensors 19, calculates the cumulative mass of eroded fine particles based on the turbidity value measured by the turbidity probe 25 and the mass increment of seepage measured by the weighing device 28, and calculates the average seepage velocity based on the volume increment of seepage per unit time and the cross-sectional area of ​​the soil-rock mixture sample 15. At the same time, it controls the applied water head and automatically adjusts the direction of hydraulic action.

[0048] The working process of the indoor test method for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action, as described in this invention, is as follows:

[0049] 1) Construct an indoor test apparatus to simulate seepage erosion of soil-rock mixtures under circulating hydraulic action. Turn on the water pressure sensor 19, turbidity probe 25 and weighing device 28 and debug the computer 29, performing zeroing and calibration.

[0050] 2) Turn on the electric guide rail 1 and adjust the liquid level of the constant head water supply tank 5 to be level with the top of the seepage chamber 14. It is determined that the hydraulic gradient in the seepage chamber 14 is 0 at this time. Turn on the water pump 9 to send the water in the storage tank 8 to the constant head water supply tank 5. The overflowing water flows back to the storage tank 8 along the guide plate 6 and the overflow channel 7.

[0051] 3) Open the automatic control electric three-way ball valve 13 and the upper outlet electric ball valve 22 to allow water to flow from bottom to top through the seepage chamber 14 until the air in the seepage chamber 14 is exhausted; use computer 29 to automatically control the electric three-way ball valve 13, the upper outlet electric ball valve 22 and the lower outlet electric ball valve 23 to control the seepage direction and change the seepage direction in the seepage chamber 14 every 10 minutes.

[0052] 4) Turn on the water pressure sensor 19, turbidity probe 25 and weighing device 28, and transmit the measured data to computer 29 in real time to start automatically and continuously recording the local water pressure in seepage chamber 14, particle concentration in particle collection tank 24 and seepage volume in water collection tank 27.

[0053] 5) Data processing: The computer 29 calculates the pore water pressure measured by each water pressure sensor 19. Total head at corresponding measuring points: ;

[0054] And calculate the first based on the total head difference and spacing between adjacent water pressure sensors. Local hydraulic gradient of each monitoring section : ;

[0055] in, The water head at the corresponding measuring point. Let g be the density of water and g be the acceleration due to gravity. The distance between the ringing water pressure sensors; based on the mass increment at adjacent sampling times of the weighing device 28. Calculate the average seepage velocity inside soil-rock mixture sample 15. and permeability coefficient :

[0056]

[0057]

[0058] in, Let be the cross-sectional area of ​​the soil-rock mixture sample 15, and i be the total hydraulic gradient applied to sample 15; based on the mass concentration of eroded fine particles output by the turbidity probe 25. Calculate the cumulative amount of eroded fine particles :

[0059]

[0060] in, It represents the increase in the volume of seepage water per unit time; when the cumulative amount of eroded fine particles or the average seepage velocity changes abruptly, the corresponding time is recorded and it is indicated that the sample is undergoing erosion and damage.

Claims

1. A test apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action, characterized in that: This includes a head control system, a circulating hydraulic seepage device, a soil and water collection system, and a data acquisition and control system; The water head control system includes an electric guide rail (1), a constant head water supply tank (5), a water storage tank (8), and a water pump (9); the electric guide rail (1) includes a slider platform (2), the slider platform (2) has a lower limit switch (3) and an upper limit switch (4), and the constant head water supply tank (5) is raised and lowered by the slider platform (2); The constant head water supply tank (5) includes a guide plate (6), an overflow trough (7) and an overflow port (11), wherein the guide plate (6) is obliquely inserted into the constant head water supply tank (5); The circulating hydraulic seepage device includes a seepage chamber (14), a soil-rock mixture sample (15), and an electric three-way ball valve (13). The seepage chamber (14) includes an upper outlet trough (16), a lower outlet trough (17), a gravel cushion layer (18), a water pressure sensor (19), an upper inlet (20), and a lower inlet (21). A waterproof gasket (31) is provided between the upper outlet trough (16) and the gravel cushion layer (18), and a waterproof gasket (31) is provided between the lower outlet trough (17) and the gravel cushion layer (18). A filter plate is provided between the upper outlet trough (16) and the seepage chamber (14), and a filter plate is provided between the lower outlet trough (17) and the seepage chamber (14). The water pressure sensors (19) are arranged at the same height intervals on the seepage chamber (14). The soil and water collection system includes a particle collection tank (24), a turbidity probe (25), a filter screen (26), a water collection tank (27), and a weighing device (28).

2. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action as described in claim 1, characterized in that: It also includes an upper outlet electric ball valve (22) and a lower outlet electric ball valve (23). The seepage chamber (14) is connected to the water head control system and the soil water collection system through an electric three-way ball valve (13), an upper outlet electric ball valve (22) and a lower outlet electric ball valve (23).

3. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action as described in claim 1, characterized in that: The data acquisition and control system includes a computer (29). The data acquisition and control system acquires the local water pressure of the sample, the concentration of eroded particles and the amount of seepage water. Based on the pore water pressure, the elevation of the measuring point and the distance between the measuring points measured by the adjacent water pressure sensor (19), the local hydraulic gradient of the corresponding section is calculated.

4. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action as described in claim 1, characterized in that: The data acquisition and control system calculates the cumulative erosion fine particle mass based on the turbidity value measured by the turbidity probe (25) and the mass increment of the seepage water measured by the weighing device (28).

5. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to claim 1, characterized in that: The data acquisition and control system calculates the average seepage velocity based on the increase in seepage volume per unit time and the cross-sectional area of ​​the soil-rock mixture sample (15).

6. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to claim 1, characterized in that: The data acquisition and control system controls the applied water head and adjusts the direction of the hydraulic action.

7. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to claim 1, characterized in that: The seepage chamber (14) is made of transparent material.

8. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to claim 1, characterized in that: A waterproof gasket (31) is placed between the upper water outlet trough (16) and the seepage chamber (14), and a waterproof gasket (31) is placed between the lower water outlet trough (17) and the seepage chamber (14).

9. The experimental apparatus for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action according to claim 1, characterized in that: The lower limiter (3) is located below the slider platform (2), and the upper limiter (4) is located above the slider platform (2).

10. A test method for simulating seepage erosion of soil-rock mixtures under circulating hydraulic action, characterized in that: The test apparatus for seepage erosion of soil-rock mixture as described in claim 1 is used, and the method includes the following steps: 1) Turn on the water pressure sensor (19), turbidity probe (25) and weighing device (28); 2) Turn on the electric guide rail (1) and adjust the liquid level of the constant head water supply tank (5) to be level with the top of the seepage chamber (14) until the hydraulic gradient in the seepage chamber (14) is zero; turn on the water pump (9) and send the water in the storage tank (8) to the constant head water supply tank (5). The water overflowing from the constant head water supply tank flows back to the storage tank (8) along the guide plate (6) and the overflow trough (7); 3) Open the electric three-way ball valve (13) and the upper outlet electric ball valve (22) to make the water flow from bottom to top through the seepage chamber (14) to exhaust the air in the seepage chamber (14); control the seepage direction and change the seepage direction in the seepage chamber (14) at set intervals; 4) Turn on the water pressure sensor (19), turbidity probe (25) and weighing device (28), and transmit the measured data to the computer (29) in real time to start continuously recording the local water pressure in the seepage chamber (14), the particle concentration in the particle collection tank (24) and the amount of seepage in the water collection tank (27); 5) Calculate the pore water pressure measured by each water pressure sensor (19). Total head at corresponding measuring points : ; And calculate the first based on the total head difference and spacing between adjacent water pressure sensors. Local hydraulic gradient of each monitoring section : ; in, The water head at the corresponding measuring point. Let g be the density of water and g be the acceleration due to gravity. The distance between the ringing water pressure sensors; According to the mass increment of the weighing device (28) at adjacent sampling times Calculate the average seepage velocity inside the soil-rock mixture sample (15) and permeability coefficient : ; ; in, Let be the cross-sectional area of ​​the soil-rock mixture sample (15), and i be the total hydraulic gradient applied to the soil-rock mixture sample (15). According to the mass concentration of erosion particles output by the turbidity probe (25) Calculate the cumulative amount of eroded fine particles : ;in, It represents the increase in the volume of seepage water per unit time. When the cumulative amount of eroded fine particles or the average seepage velocity changes abruptly, the corresponding time is recorded and the sample is indicated to be undergoing erosion and damage.

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