A seepage erosion test system and method

Abstract

The invention discloses a seepage erosion test system and method, which comprises a seepage erosion test device, an automatic water supply device, a height adjustment device and a data acquisition system. In the seepage erosion test system, the electric signal between a water pump, a control box and a float liquid level gauge is used to realize automatic water supply and unchanged liquid level in a water supply cylinder; a micro electric crane is used to work in combination with a steel strand, a pulley and the like to freely adjust the pressurized water head; and a compiled LABVIEW control program is used to monitor and obtain the change of the permeability performance of a soil sample in the seepage erosion test device in real time. The whole system is highly integrated and has a high degree of automation.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering test devices, and in particular relates to a seepage erosion test system. Background Art

[0002] The phenomenon of pipe burst in earth-rock dams caused by reservoir water level and soil parameters, as well as landslides, mudslides and other geological disasters caused by slope runoff erosion, all involve the migration and flow of fine particles in soil pores during seepage. At present, there are indoor model tests that use the constant head method to simulate the changes in soil permeability, shear strength, particle grading, etc. caused by fine particle erosion, but they face the problem that the pressurized head cannot be adjusted freely and it is difficult to determine the changing trend of the overall permeability of the soil during seepage erosion.

[0003] In summary, how to effectively solve the problem that the pressure head on the upper surface of the sample in the seepage erosion test device cannot be freely adjusted, and how to accurately measure the changes in the overall permeability of the soil during the seepage erosion process are problems that technical personnel in this field urgently need to solve. Summary of the invention

[0004] In order to overcome the above defects and shortcomings, the present invention discloses a seepage erosion test system which can freely adjust the pressure head and accurately measure the change of the overall permeability of the soil during the seepage erosion process, and accurately measure the loss of fine particles. The experimental system utilizes the linear relationship between liquid pressure and vertical distance, and adopts an electric method to realize the free adjustment of the pressure head at the upper surface of the sample in the seepage erosion device, and utilizes a water pump, a control box and a float level gauge to achieve constant liquid level. The pressure signals measured by pressure sensors at various locations are transmitted to a PC through wires through a data acquisition card, and finally the data information is directly read through a window.

[0005] In order to realize the above-mentioned technical features, the object of the present invention is realized as follows: a seepage erosion test system, which includes a seepage erosion test device, an automatic water supply device, a height adjustment device and a data acquisition system; the water inlet at the top of the seepage erosion test device is provided with a valve, and is connected to the water supply cylinder of the automatic water supply device through a conduit, and a particle collection bucket for collecting lost fine particles is placed under the water outlet at the bottom end of the seepage erosion test device, and the particle collection bucket is connected to the liquid storage bucket; the automatic water supply device cooperates with the height adjustment device and adjusts the pressure head; the seepage erosion test device is connected to the data acquisition system through a signal line.

[0006] The top water inlet valve of the seepage erosion test device is provided with an exhaust pipeline, a water inlet pipeline, and a saturated water inlet pipeline connected to the water inlet pipeline through a three-way connector, and valves for controlling water flow are provided on the three pipelines.

[0007] A filter test block is obliquely placed at one corner of the bottom of the particle collection barrel, and multiple layers of filter paper are wrapped on the filter test block. The filter test block is made of porous and permeable material; the bottom of the particle collection barrel and the filter test block on the same side is connected to the liquid storage barrel through a water pipe.

[0008] Pressure sensors are arranged at the water inlet at the top of the seepage erosion test device, at 1 / 3 and 2 / 3 of the height of the sample tube wall, and at the bottom of the liquid storage barrel. The pressure sensors transmit signals to a data acquisition card through wires, and the data acquisition card is connected to a PC.

[0009] The seepage erosion test device has multiple groups and adopts a parallel structure. The water inlet pipeline of each seepage erosion test device is connected to the main pipeline through a three-way or four-way joint.

[0010] The automatic water supply device comprises a water pump, the water inlet end of the water pump is connected to the water tank, and the water outlet end is connected to the water inlet of the water supply cylinder through a water guide pipe.

[0011] A water inlet is arranged at the top of the water supply cylinder, and a water outlet valve is arranged at the bottom; a circular level bubble is arranged at the center of the barrel cover on the top of the water supply cylinder; a control box and a float level gauge are placed on the barrel cover on the top of the water supply cylinder, and the control box is connected to the water pump and the float level gauge through wires respectively, and the float level gauge has a rod with a float extending into the water, and the control box, the water pump and the float level gauge cooperate to realize automatic water supply in the water supply cylinder and keep the liquid level unchanged.

[0012] The height adjustment device includes a micro electric crane and a lifting bracket, on which a support platform with slidable height adjustment is placed, on which a water supply cylinder is placed, and the support platform is connected to the micro electric crane through a steel strand, a movable pulley and a fixed pulley fixed to the top of the bracket.

[0013] The data acquisition system comprises a pressure sensor, the pressure sensor is connected to a data acquisition card via a signal line, and the data acquisition card is connected to a PC.

[0014] The test method using any one of the seepage erosion test systems comprises the following steps:

[0015] Step 1: Exhaust bubbles: First, turn on the water pump to pump water into the water supply cylinder and maintain a constant water head. Open the outlet valve, the fourth valve, and the third valve in the water supply cylinder. Keep the first and second valves closed. When a stable and continuous water flow flows out from the end of the saturated water inlet pipeline, the bubbles in the main pipeline and the saturated water inlet pipeline have been exhausted. At this time, close the third valve, open the second valve and the first valve, exhaust the bubbles in the water inlet pipeline, and finally close the second valve.

[0016] Step 2: Saturation: Connect the end of the saturated water inlet pipe to the outlet valve at the bottom of the seepage erosion test device, open the third valve, the outlet valve at the bottom of the seepage erosion test device, and the inlet valve at the top of the seepage erosion test device in sequence, so that the water flow slowly infiltrates the entire sample. When a continuous water flow gushes out of the end of the exhaust pipe without bubbles, close the first valve, the inlet valve at the top of the seepage erosion test device, the outlet valve at the bottom of the seepage erosion test device, and the third valve, disconnect the end of the saturated water inlet pipe from the outlet valve at the bottom of the seepage erosion test device, and let the sample stand for a period of time to be saturated;

[0017] Step 3: Seepage erosion test: Open the data acquisition system in the PC, open the second valve, the water inlet valve at the top of the seepage erosion test device, and the water outlet valve at the bottom of the seepage erosion test device in sequence, and the seepage test begins. When water flows through the sample, it will bring out fine particles in the pores of the sample. The fine particles flow into the particle collection bucket through the water outlet valve. The fine particles are filtered by the filter block and remain in the particle collection bucket, while the water carrying fine particles continues to flow into the liquid storage bucket. At the same time, the pressure sensors at all four sides transmit the measured pressure signals to the computer;

[0018] Step 4: Calculation: The pressure signal transmitted to the computer by the pressure sensor at the top water inlet of the seepage erosion test device will be corrected to the pressure signal on the upper surface of the sample through the written program. At this time, the sample is equivalent to having three pressure sensors installed. The readings of these three pressure sensors from top to bottom are set as p m , p n , p s , assuming that the reading of the pressure sensor at the liquid storage tank is p k , the data acquisition system takes a reading every Δt, t i The sensor readings at each moment are shown in the table below:

[0019]

[0020] According to the calculation method of constant head permeability coefficient in the "Standard for Geotechnical Test Methods" and the data information collected in this test system, t i The calculation formula of the average permeability coefficient of the sample at the time is:

[0021]

[0022]

[0023]

[0024] in:

[0025] ——When the water temperature is T℃t i-1 toi The average permeability coefficient of the sample over time (cm / s);

[0026] Q i ——t i-1 to i Water seepage in time (cm 3 );

[0027] L——the distance between the centers of the two pressure sensors (cm);

[0028] A——Cross-sectional area of ​​the sample (cm 2 );

[0029] H i ——t i Average water level difference at each moment (cm);

[0030] Δt——t i-1 to i Time interval (s);

[0031] S——Cross-sectional area of ​​liquid storage tank (cm 2 );

[0032] ——t i The reading of the pressure sensor at the liquid storage tank at the moment (Pa);

[0033] ——t i-1 The reading of the pressure sensor at the liquid storage tank at the moment (Pa);

[0034] ——t i The reading of the pressure sensor at the outlet of the seepage erosion test device at any moment (Pa);

[0035] ——t i The reading of the second pressure sensor from top to bottom of the seepage erosion test device at any moment (Pa);

[0036] ——t i The reading of the third pressure sensor from top to bottom of the seepage erosion test device at any moment (Pa);

[0037] This can be used to learn the continuous change of the permeability coefficient of the sample at each moment during the test period under a certain hydraulic gradient; when the hydraulic gradient needs to be adjusted, press the button of the micro electric crane to adjust the water supply cylinder to the required height; the collection and weighing of fine particles can be carried out after each hydraulic gradient or the entire seepage erosion test is completed; after the test is completed, close all valves, organize the test instruments and test data and subsequent related tests.

[0038] The present invention has the following beneficial effects:

[0039] 1. The present invention is a new type of test system. The required materials are easy to buy in the market or on the Internet, and the experimental operation is relatively convenient.

[0040] 2. The present invention can not only carry out one set of seepage erosion tests, but also can carry out multiple sets of parallel tests at the same time, which can greatly improve the test efficiency while ensuring the test precision and accuracy;

[0041] 3. It has a high-speed USB compatible interface, which can be connected to a PC and use the program to realize the data collection work of the PC for the entire system, with a high degree of automation.

[0042] 4. The present invention utilizes the conversion and transmission of electrical signals between a float level gauge, a control box and a water pump to achieve the effect of detecting and controlling the liquid level position, which can not only ensure accuracy but also save manpower and has a high degree of automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0044] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0045] Figure 2 It is a schematic diagram of the structure of the seepage erosion test device and the particle and liquid collection device of the present invention.

[0046] Figure 3 This is a schematic diagram of the water supply cylinder installation structure of the present invention.

[0047] Figure 4 It is a schematic diagram of the structure of the height adjustment device of the present invention.

[0048] In the figure: 1 PC; 2 seepage erosion test device; 3 micro electric crane; 4 water supply cylinder; 5 lifting bracket; 6 water pump; 7 water tank; 8 particle collection bucket; 9 liquid storage bucket; 10 data acquisition card; 0 pressure sensor; 3-1 steel strand; 3-2 movable pulley; 3-3 fixed pulley; 4-1 control box; 4-2 float level gauge; 4-3 water inlet; 4-4 water outlet valve; 4-5 circular level bubble; 5-1 support table; 8-1 filter test block; A exhaust pipeline; B water inlet pipeline; C saturated water inlet pipeline; D main pipeline; a first valve; b second valve; c third valve; d fourth valve. DETAILED DESCRIPTION

[0049] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0050] Embodiment 1:

[0051] See also Figure 1-4 , a seepage erosion test system, which includes a seepage erosion test device 1, an automatic water supply device, a height adjustment device and a data acquisition system.

[0052] Furthermore, a valve is provided at the water inlet at the top of the seepage erosion test device 1 and is connected to the water supply cylinder 4 through a conduit. A particle collection bucket 8 is placed under the water outlet at the bottom of the seepage erosion test device 1 to facilitate the collection of lost fine particles.

[0053] Furthermore, the automatic water supply device includes a water supply cylinder 4, a water pump 6, and a water tank 7 placed on the ground, so as to realize the automatic supply of water in the water supply cylinder 4 and maintain the liquid level unchanged.

[0054] Furthermore, the height adjustment device includes a micro electric crane 3 and a lifting bracket 5, and the pressure head is adjusted through the operation of the micro electric crane 3, which saves time and labor.

[0055] Furthermore, the data acquisition system includes a pressure sensor 0, a data acquisition card 10, and a PC 1, and can realize automation of data reading.

[0056] Furthermore, the water inlet valve at the top of the seepage erosion test device 1 is provided with an exhaust pipe A, a water inlet pipe B, and a saturated water inlet pipe C connected to the water inlet pipe B via a tee, and valves for controlling water flow are provided on the three pipes.

[0057] Furthermore, a filter block 8-1 is obliquely placed at one corner of the particle collection barrel 8, and two layers of chronic filter paper are wrapped on the filter block 8. The filter block 8 can use porous structures such as permeable stone to facilitate collecting the outflowing particles and discharging water.

[0058] Furthermore, the bottom of the particle collection barrel 8 on the same side as the filter test block 8 - 1 is connected to the liquid storage barrel 9 through a water pipe, so as to collect the water discharged from the particle collection barrel 8 .

[0059] Furthermore, pressure sensors 0 are provided at the water inlet at the top of the seepage erosion test device 1, at 1 / 3 and 2 / 3 of the height of the sample tube wall, and at the bottom of the liquid storage barrel 9. The pressure sensor 0 transmits the signal to the data acquisition card 10 through a wire. The data acquisition card 10 is connected to the PC 1. Finally, the LABVIEW control interface is written through the PC 1, and the pressure information is directly read through the window. The degree of automation is high and the test results are more accurate.

[0060] Furthermore, by adding a three-way head, a four-way head or a multi-way head in the main pipeline D, multiple groups of parallel tests can be carried out simultaneously, greatly improving the test efficiency.

[0061] Furthermore, the water inlet end of the water pump 6 in the automatic water supply device is connected to the water tank 7, and the water outlet end is connected to the water inlet 4-3 of the water supply cylinder 4 through a water pipe. The water in the water tank 7 is pumped into the water supply cylinder 4 by the water pump 6, providing power for water transportation.

[0062] Furthermore, a water inlet 4-3 is arranged at the top of the water supply cylinder 4, and a water outlet valve 4-4 is arranged at the bottom.

[0063] Furthermore, a circular level bubble 4-5 is provided at the center of the top cover of the water supply cylinder 4, and a monitoring support platform 5-1 is provided to ensure that the position of the water supply cylinder 4 is balanced.

[0064] Furthermore, a control box 4-1 and a float level gauge 4-2 are mounted on the top cover of the water supply cylinder 4. The control box 4-1 is connected to the water pump 6 and the float level gauge 4-2 through wires, wherein the float level gauge 4-2 has a rod with a float extending into the water. Through the joint action of the control box 4-1, the water pump 6 and the float level gauge 4-2, automatic water supply is achieved in the water supply cylinder 4 without changing the liquid level.

[0065] Furthermore, a support platform 5-1 with a slidable height adjustment is arranged on the lifting bracket 5, and a water supply cylinder 4 is placed on the support platform 5-1. The support platform 5-1 is connected to the micro electric crane 3 through a steel strand 3-1, a movable pulley 3-2 and a fixed pulley 3-3 fixed to the top of the bracket. The pressure head is adjusted by electric means, which saves time and effort while ensuring accuracy.

[0066] Embodiment 2:

[0067] The test method using any one of the seepage erosion test systems comprises the following steps:

[0068] Step 1: exhaust bubbles: first open the water pump 6 to pump water into the water supply cylinder 4 and maintain a constant water head, open the outlet valve 4-4, the fourth valve d, and the third valve c in the water supply cylinder 4, and keep the first valve a and the second valve b closed. When a stable and continuous water flow flows out from the end of the saturated water inlet pipeline C, the bubbles in the main pipeline D and the saturated water inlet pipeline C have been exhausted. At this time, close the third valve c, open the second valve b and the first valve a, exhaust the bubbles in the water inlet pipeline B, and finally close the second valve b;

[0069] Step 2: Saturation: Connect the end of the saturated water inlet pipe C to the water outlet valve at the bottom of the seepage erosion test device 2, and open the third valve c, the water outlet valve at the bottom of the seepage erosion test device 2, and the water inlet valve at the top of the seepage erosion test device 2 in sequence, so that the water flow slowly infiltrates the entire sample. When a continuous water flow gushes out from the end of the exhaust pipe A without bubbles, close the first valve a, the water inlet valve at the top of the seepage erosion test device 2, the water outlet valve at the bottom of the seepage erosion test device 2 and the third valve c, disconnect the end of the saturated water inlet pipe C and the water outlet valve at the bottom of the seepage erosion test device 2, and let the sample stand for a period of time to be saturated;

[0070] Step 3: Seepage erosion test: Open the data acquisition system in the PC 1, open the second valve b, the water inlet valve at the top of the seepage erosion test device 2, and the water outlet valve at the bottom of the seepage erosion test device 2 in sequence, and the seepage test begins. When water flows through the sample, it will bring out fine particles in the pores of the sample. The fine particles flow into the particle collection barrel 8 through the water outlet valve. The fine particles are filtered by the filter block 8-1 and remain in the particle collection barrel 8, while the water carrying fine particles continues to flow into the liquid storage barrel 9. At the same time, the pressure sensors 0 at four locations transmit the measured pressure signals to the computer;

[0071] Step 4: Calculation: The pressure signal transmitted to the computer by the pressure sensor 0 at the top water inlet of the seepage erosion test device 2 will be corrected to the pressure signal on the upper surface of the sample through the written program. At this time, the sample is equivalent to having three pressure sensors 0. The readings of these three pressure sensors 0 from top to bottom are set as p m , p n , p s , assuming that the reading of the pressure sensor 0 at the liquid storage tank 9 is p k , the data acquisition system takes a reading every Δt, t i The sensor readings at each moment are shown in the table below:

[0072]

[0073]

[0074] According to the calculation method of constant head permeability coefficient in the "Standard for Geotechnical Test Methods" and the data information collected in this test system, t i The calculation formula of the average permeability coefficient of the sample at the time is:

[0075]

[0076]

[0077]

[0078] in:

[0079] ——When the water temperature is T℃t i-1 to i The average permeability coefficient of the sample over time (cm / s);

[0080] Q i ——t i-1 to i Water seepage in time (cm 3 );

[0081] L——the distance between the centers of the two pressure sensors (cm);

[0082] A——Cross-sectional area of ​​the sample (cm 2 );

[0083] H i ——t i Average water level difference at each moment (cm);

[0084] Δt——t i-1 to i Time interval (s);

[0085] S——Cross-sectional area of ​​liquid storage tank (cm 2 );

[0086] ——t i The reading of the pressure sensor at the liquid storage tank at the moment (Pa);

[0087] ——t i-1 The reading of the pressure sensor at the liquid storage tank at the moment (Pa);

[0088] ——t i The reading of the pressure sensor at the outlet of the seepage erosion test device at any moment (Pa);

[0089] ——t i The reading of the second pressure sensor from top to bottom of the seepage erosion test device at any moment (Pa);

[0090] ——t i The reading of the third pressure sensor from top to bottom of the seepage erosion test device at any moment (Pa);

[0091] Thus, the continuous change of the permeability coefficient of the whole sample at each moment in the test time period under a certain hydraulic gradient can be known; when the hydraulic gradient needs to be adjusted, the button of the micro electric crane 3 is pressed to adjust the water supply cylinder 4 to the required height; the collection and weighing of fine particles can be carried out after each hydraulic gradient or the entire seepage erosion test is completed; after the test is completed, the valves are closed, and the test instruments and test data and subsequent related tests are organized.

[0092] The above embodiments are used to illustrate the present invention rather than to limit the present invention. Any modification and change made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A test method for a seepage erosion test system, the seepage erosion test system comprising a seepage erosion test device (2), an automatic water supply device, a height adjustment device and a data acquisition system; the water inlet at the top of the seepage erosion test device (2) is provided with a valve, and is connected to a water supply cylinder (4) of the automatic water supply device through a conduit; a particle collection bucket (8) for collecting lost fine particles is placed under the water outlet at the bottom of the seepage erosion test device (2), and the particle collection bucket (8) is connected to a liquid storage bucket (9); the automatic water supply device cooperates with the height adjustment device and adjusts the pressure head; the seepage erosion test device (2) is connected to the data acquisition system through a signal line; The automatic water supply device comprises a water pump (6), the water inlet end of the water pump (6) is connected to the water tank (7), and the water outlet end is connected to the water inlet (4-3) of the water supply cylinder (4) through a water guide pipe; The water supply cylinder (4) is provided with a water inlet (4-3) at the top and a water outlet valve (4-4) at the bottom; a circular level bubble (4-5) is provided at the center of the top barrel cover of the water supply cylinder (4); a control box (4-1) and a float liquid level gauge (4-2) are arranged on the top barrel cover of the water supply cylinder (4); the control box (4-1) is connected to the water pump (6) and the float liquid level gauge (4-2) respectively through wires; the float liquid level gauge (4-2) has a rod with a float extending into the water, and the control box (4-1), the water pump (6) and the float liquid level gauge (4-2) cooperate to realize automatic water supply in the water supply cylinder (4) and keep the liquid level unchanged; A filter test block (8-1) is obliquely placed at one corner of the bottom of the particle collection barrel (8), the filter test block (8-1) is covered with multiple layers of filter paper, and the filter test block (8-1) is made of a porous water-permeable material; the bottom of the particle collection barrel (8) and the filter test block (8-1) on the same side is connected to the liquid storage barrel (9) through a water pipe; Pressure sensors (0) are provided at the water inlet at the top of the seepage erosion test device (2), at 1 / 3 and 2 / 3 of the height of the sample tube wall, and at the bottom of the liquid storage barrel (9). The pressure sensor (0) transmits a signal to a data acquisition card (10) via a wire. The data acquisition card (10) is connected to a PC (1). The height adjustment device comprises a micro electric crane (3) and a lifting bracket (5); a support platform (5-1) capable of sliding and adjusting the height is arranged on the lifting bracket (5); a water supply cylinder (4) is placed on the support platform (5-1); the support platform (5-1) is connected to the micro electric crane (3) via a steel strand (3-1), a movable pulley (3-2), and a fixed pulley (3-3) fixed to the top of the bracket; The data acquisition system comprises a pressure sensor (0), the pressure sensor (0) being connected to a data acquisition card (10) via a signal line, and the data acquisition card (10) being connected to a PC (1); It is characterized in that The test method comprises the following steps: Step 1: Exhaust bubbles: First, turn on the water pump (6) to pump water into the water supply cylinder (4) and maintain a constant water head. Open the outlet valve (4-4), the fourth valve (d), and the third valve (c) in the water supply cylinder (4). Keep the first valve (a) and the second valve (b) closed. When a stable and continuous water flow flows out from the end of the saturated water inlet pipeline (C), the bubbles in the main pipeline (D) and the saturated water inlet pipeline (C) have been exhausted. At this time, close the third valve (c), open the second valve (b) and the first valve (a), exhaust the bubbles in the water inlet pipeline (B), and finally close the second valve (b). Step 2: Saturation: Connect the end of the saturated water inlet pipe (C) to the outlet valve at the bottom of the seepage erosion test device (2), and open the third valve (c), the outlet valve at the bottom of the seepage erosion test device (2), and the inlet valve at the top of the seepage erosion test device (2) in sequence, so that the water flow slowly infiltrates the entire sample. When a continuous water flow without bubbles gushes out from the end of the exhaust pipe (A), close the first valve (a), the inlet valve at the top of the seepage erosion test device (2), the outlet valve at the bottom of the seepage erosion test device (2), and the third valve (c), disconnect the end of the saturated water inlet pipe (C) and the outlet valve at the bottom of the seepage erosion test device (2), and allow the sample to stand for a period of time to become saturated; Step 3: Seepage erosion test: Open the data acquisition system in the PC (1), open the second valve (b), the water inlet valve at the top of the seepage erosion test device (2), and the water outlet valve at the bottom of the seepage erosion test device (2) in sequence, and start the seepage test. When water flows through the sample, it will bring out fine particles in the pores of the sample. The fine particles flow into the particle collection bucket (8) through the water outlet valve. The fine particles are filtered by the filter block (8-1) and remain in the particle collection bucket (8). The water carrying the fine particles continues to flow into the liquid storage bucket (9). At the same time, the four pressure sensors (0) transmit the measured pressure signals to the computer; Step 4: Calculation: The pressure signal transmitted to the computer by the pressure sensor (0) at the top water inlet of the seepage erosion test device (2) is corrected to the pressure signal on the upper surface of the sample through the programmed program. At this time, the sample is equivalent to having three pressure sensors (0) set up. The readings of these three pressure sensors (0) from top to bottom are , , , assuming that the reading of the pressure sensor (0) at the liquid storage tank (9) is , the data acquisition system is Read once, The sensor readings at each moment are shown in the table below: According to the calculation method of constant head permeability coefficient in the "Standard for Geotechnical Test Methods" and the data information collected in this test system, The calculation formula of the average permeability coefficient of the sample at the time is: （1） （2） （3） in: ——Water temperature is hour to The average permeability coefficient of the sample over time ( ); —— to The amount of water seepage during the time period ( ); ——The distance between the centers of the two pressure sensors ( ); ——Cross-sectional area of ​​the specimen ( ); —— Average water level difference at any time ( ); —— to Time interval ( ); ——Cross-sectional area of ​​liquid storage tank ( ); —— The reading of the pressure sensor at the liquid storage tank at the moment ( ); —— The reading of the pressure sensor at the liquid storage tank at the moment ( ); —— The reading of the pressure sensor at the outlet of the seepage erosion test device at the moment ( ); —— The reading of the second pressure sensor from top to bottom of the seepage erosion test device at the same time ( ); —— The reading of the third pressure sensor from top to bottom of the seepage erosion test device at that moment ( ); Thus, the continuous change of the permeability coefficient of the whole sample at each moment in the test time period under a certain hydraulic gradient can be known; when the hydraulic gradient needs to be adjusted, the button of the micro electric crane (3) is pressed to adjust the water supply cylinder (4) to the required height; the collection and weighing of fine particles can be carried out after each hydraulic gradient or the entire seepage erosion test is completed; after the test is completed, the valves are closed, and the test instruments and test data and subsequent related tests are sorted out.

2. The test method of the seepage erosion test system according to claim 1, characterized in that: The top water inlet valve of the seepage erosion test device (2) is provided with an exhaust pipeline (A), a water inlet pipeline (B), and a saturated water inlet pipeline (C) connected to the water inlet pipeline (B) via a three-way connector, and valves for controlling water flow are provided on all three pipelines.

3. The test method of the seepage erosion test system according to claim 1, characterized in that: The seepage erosion test device (2) comprises multiple groups, which adopt a parallel structure. The water inlet pipeline (B) of each seepage erosion test device (2) is connected to the main pipeline (D) through a three-way or four-way joint.

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