Double-ring type soil water permeability detection method

Abstract

The invention discloses a double-ring type soil water permeability detection method, and relates to the technical field of soil water permeability detection, and the method comprises the following steps: S1, collecting a soil sample, removing large particles and vegetation residues, and retaining an original soil structure; s2, vertically pressing the double-ring infiltration instrument into the soil, and ensuring that the double-ring infiltration instrument is vertical to the ground; s3, water is injected into the inner ring and the outer ring at the same time, the water surface height reaches the set scale, the soil initial moisture is controlled to reach the stable state, and the initial water level is recorded. According to the method, water can gradually and uniformly enter the soil by adopting a mode of respectively injecting water for multiple times at an interval of ten minutes, so that the situation of excessive local water of the soil and insufficient water of other parts possibly caused by one-time large-amount water injection is avoided, the soil has enough time to absorb the water after each time of water injection, and the soil quality is improved. The moisture gradually diffuses in soil pores, so that the uniform distribution of the moisture in the soil is more effectively promoted.

Description

Technical Field

[0001] The invention relates to the technical field of soil water seepage detection, in particular to a double-loop soil water seepage detection method. Background Art

[0002] Hydrogeological survey is to collect environmental hydrogeological data, conduct hydrogeological investigation and supplementary exploration to find out the groundwater recharge runoff conditions and boundary conditions of the hydrogeological unit in the study area, the dynamics of groundwater quality and water level changes, groundwater development and utilization, relevant hydrogeological parameters of the vadose zone and aquifers, hydraulic connections between aquifers, etc., to evaluate the water quality and quantity of groundwater in the study area and predict the possible impact of project construction on groundwater. In hydrogeological survey, the hydrogeological parameters of the vadose zone are usually obtained through test pit seepage tests.

[0003] The commonly used methods for test pit water seepage test are test pit method, single ring method and double ring method. Among them, the test pit method has a simple device, is greatly affected by lateral seepage, and the test result accuracy is poor; the single ring method has a simple device, is greatly affected by lateral seepage, and the test result accuracy is slightly poor; the double ring method has a more complex device, basically eliminates the influence of lateral seepage, and the test result accuracy is higher.

[0004] However, in actual application of the existing double-ring method, the initial moisture of the soil is affected by local climatic conditions, including rainfall, evaporation, etc. Different environmental conditions may cause significant fluctuations in the initial moisture state of the soil, and it is difficult to control the stability of the initial moisture state. If a stable initial moisture state is not fully achieved, it may cause deviations in the measurement results, thereby affecting the permeability test results. Summary of the invention

[0005] The object of the present invention is to provide a dual-ring soil permeability detection method to solve the problem proposed in the above background technology that different environmental conditions may cause significant fluctuations in the initial moisture state of the soil, and it is difficult to control the stability of the initial moisture state. If a stable initial moisture state is not fully achieved, it may cause measurement result deviations, thereby affecting the permeability detection results.

[0006] To achieve the above object, the present invention provides the following technical solution: a double-loop soil water permeability detection method, comprising the following steps:

[0007] S1. Collect soil samples, remove larger particles and vegetation residues, and retain the original soil structure. For areas with a small area and a relatively single soil type, the grid spacing can be set to 5 meters; for areas with a large area and obvious differences in soil types, the grid spacing can be appropriately adjusted to 10-15 meters;

[0008] S2. Press the double-ring infiltration meter vertically into the soil to ensure that the double-ring infiltration meter is perpendicular to the ground. The double-ring infiltration meter consists of an inner ring and an outer ring. The inner ring has a diameter of 15-20 cm, the outer ring has a diameter of 30-40 cm, and the height is generally 30-50 cm.

[0009] S3. Inject water into the inner and outer rings simultaneously, so that the water level reaches the set mark and the initial soil moisture is controlled to reach a stable state. Record the initial water level. During the water injection process, pay attention to controlling the water flow rate to avoid excessive water flow that scours the soil surface and destroys the soil structure.

[0010] S4. Use an electronic water level sensor to regularly measure the water levels of the inner and outer rings, and record the time and corresponding water level;

[0011] S5. Continue observation after determining that the soil permeability has reached a stable state. When the test is finished, record the final water level data and time.

[0012] S6. Calculate the permeability of the target soil based on the test data, output the water level change curve, and analyze the trend of permeability change over time.

[0013] Preferably, in step S1, the process of collecting soil samples is as follows: in the target detection area, multiple sampling points are set according to a certain grid spacing, and 3-5 representative detection points are selected for sample collection according to the distribution of soil characteristics, so as to reduce the measurement error caused by the difference in local soil characteristics and improve the reliability of the detection results. During the collection process, larger particles and vegetation residues are removed by sieve or manually to ensure the purity of the sample, retain the original soil structure, and avoid excessive damage to the arrangement of soil particles and pore structure, because the integrity of the soil structure has an important influence on its water permeability.

[0014] Preferably, in step S2, the vertical insertion depth of the double-ring infiltrator is 20-30 cm, which can not only ensure that the instrument is in full contact with the soil, but also avoid damaging the deep structure of the soil due to too deep insertion or causing water leakage due to too shallow insertion and affecting the test results. After the insertion is completed, the soil around the outer wall of the ring is properly compacted to prevent water from leaking out of the ring.

[0015] Preferably, in step S3, controlling the initial soil moisture to reach a stable state comprises the following steps:

[0016] S31. Inject water several times, with an interval of ten minutes between each injection, observe the water level changes, and record the speed and amplitude of the water level drop to understand the soil's absorption of water;

[0017] S32. After the water is fully injected, the soil is left to stand for 30 to 60 minutes to allow the water to be fully distributed in the soil and reach a more uniform initial water content through the capillary action of the soil pores and gravity.

[0018] S33. During this period, regularly observe whether the water level records of the inner and outer rings have dropped significantly. If the water level is stable and no longer changes, it means that the initial moisture of the soil has roughly reached a stable state. At this time, record the initial water level as the benchmark data for subsequent tests.

[0019] Preferably, in step S5, the criteria for judging whether the soil permeability has reached a stable state include: water level change monitoring and flow rate monitoring;

[0020] Water level change monitoring: During the detection process, the water level changes of the inner and outer rings are measured regularly. When the difference in water level changes between two consecutive observations is no more than 5%, it is judged that the soil permeability has stabilized;

[0021] Flow monitoring: record the flow per unit time, that is, the amount of water flowing in and out. When the difference between two consecutive flow observation results is less than the preset threshold, it indicates that the soil permeability has reached a stable state.

[0022] Preferably, in step S5, the continued observation includes the following steps:

[0023] S51. After initially judging that the water level change and flow are basically stable, continue to observe for 2-3 hours and record the water level change every 5 minutes. By extending the observation time and increasing the observation frequency, you can have a more comprehensive understanding of the stability of soil permeability over a longer period of time.

[0024] S52. During the extended observation period, the electronic water level sensor shall continue to be used to automatically record the water level changes of the inner and outer rings. The data shall be updated in real time. The data recording device shall store and process the real-time acquired water level data for subsequent analysis.

[0025] S53, recording the water inflow and outflow at each time point and performing flow comparison analysis, by comparing the flow data at different time points, observing the change trend of the flow, and judging whether the soil permeability is continuously stable;

[0026] S54. When the water level or flow rate remains within the set threshold value and no longer changes significantly during multiple consecutive observation cycles, the continuous observation is terminated and the final water level data and time are recorded.

[0027] Preferably, in step S6, the calculation of the permeability of the target soil adopts the following formula:

[0028]

[0029] Among them, h in and h out are the water level changes of the inner and outer rings respectively, A is the cross-sectional area of ​​the inner ring, t is the time, and L is the length of the soil column.

[0030] Preferably, in step S6, the output water level change curve graph uses data visualization software to plot the water level change data into a curve graph to intuitively display the trend of permeability change over time.

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

[0032] 1. In this method, by adopting multiple water injections with an interval of ten minutes each time, water can enter the soil gradually and evenly, thus avoiding the situation where a large amount of water injection at one time may cause excessive moisture in some parts of the soil and insufficient moisture in other parts. After each water injection, the soil has enough time to absorb moisture, and the moisture gradually diffuses in the soil pores, thereby more effectively promoting the uniform distribution of moisture in the soil.

[0033] 2. In this method, static observation is carried out after complete water injection, which provides sufficient time for the water to fully penetrate and distribute in the soil. During this period, the water in the soil is further diffused and redistributed in the soil pores through gravity, capillary action, etc., so that the soil reaches a more uniform initial water content state. By continuing observation after the soil permeability has reached a stable state, extending the observation time and increasing the observation frequency, a more comprehensive understanding of the stability of soil permeability over a longer period of time can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The present invention is a flow chart of a double-loop soil water permeability detection method. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Embodiment 1: The present invention provides a technical solution: a double-loop soil water permeability detection method, comprising the following steps:

[0037] Step 1: Collect soil samples from the first area, remove larger particles and vegetation residues, and retain the original soil structure; the process of collecting soil samples: set sampling points at a grid spacing of 10 meters × 10 meters in the target detection area, select 3 representative detection points for sample collection based on the distribution of soil characteristics, and use a sieve or manually remove larger particles and vegetation residues during the collection process to ensure the purity of the sample;

[0038] Step 2: Prepare a double-ring infiltration instrument with an inner ring diameter of 15 cm, an outer ring diameter of 30 cm, and a height of 30 cm. Press the double-ring infiltration instrument vertically into the soil to ensure that the double-ring infiltration instrument is perpendicular to the ground. The vertical insertion depth of the double-ring infiltration instrument is 20 cm. Use a level to ensure that the double rings are perpendicular to the ground. Use soil to tamp the outer wall of the ring to prevent water leakage.

[0039] Step 3: Pour water into the inner and outer rings simultaneously until the water level reaches the mark of 15 cm from the top of the ring and the initial soil moisture is controlled to reach a stable state, and the initial water level is recorded;

[0040] Among them, controlling the initial soil moisture to reach a stable state includes the following steps:

[0041] 31) Inject water several times, with an interval of ten minutes between each injection, and observe the water level changes;

[0042] 32) After the water is fully injected, let it stand for 45 minutes to allow the water to be fully distributed in the soil and reach a more uniform initial moisture state;

[0043] 33) During this period, observe the water levels of the inner and outer rings every 15 minutes to see if the water level records of the inner and outer rings have dropped significantly. If the water level is stable and no longer changes, it means that the initial soil moisture has roughly reached a stable state. When the water level is stable, record the initial water level;

[0044] Step 4: Use the electronic water level sensor to measure the water level of the inner and outer rings every 2 minutes, and record the time and the corresponding water level;

[0045] Step 5: Continue observation after determining that the soil permeability has reached a stable state. When the test is finished, record the final water level data and time. The criteria for determining that the soil permeability has reached a stable state include: water level change monitoring and flow monitoring;

[0046] Water level change monitoring: During the detection process, the water level changes of the inner and outer rings are measured regularly. When the difference in water level changes in two consecutive observations is no more than 5%, it is judged that the soil permeability has stabilized;

[0047] Flow monitoring: record the flow rate per unit time, that is, the amount of water flowing in and out. When the difference between two consecutive flow observation results is less than the preset threshold, it indicates that the soil permeability has reached a stable state;

[0048] Among them, the continued observation includes the following steps:

[0049] 51) After initially judging that the water level change and flow are basically stable, continue to observe for 2 hours and record the water level change every 5 minutes;

[0050] 52) During the extended observation period, the electronic water level sensor shall continue to automatically record the water level changes of the inner and outer rings, and the data shall be updated in real time;

[0051] 53) Record the water inflow and outflow at each time point and conduct flow comparison analysis;

[0052] 54) When the water level or flow rate remains within the set threshold and no longer changes significantly during multiple consecutive observation cycles, the observation is terminated and the final data is recorded;

[0053] Step 6: Calculate the permeability of the target soil based on the test data, output the water level change curve, and analyze the trend of permeability change over time; the permeability of the target soil is calculated using the following formula:

[0054]

[0055] Among them, h in and h out are the water level changes of the inner and outer rings respectively, A is the cross-sectional area of ​​the inner ring, t is the time, and L is the length of the soil column.

[0056] In this embodiment, after calculating the data of the three detection points, the soil permeability at different positions in the detection area is obtained as follows: the permeability of detection point 1: K1 = 0.35 cm / min, the permeability of detection point 2: K2 = 0.32 cm / min, the permeability of detection point 3: K3 = 0.33 cm / min, and the average soil permeability of the area is: K 平均1 =0.33cm / min.

[0057] Embodiment 2: The present invention provides a technical solution: a double-loop soil water permeability detection method, comprising the following steps:

[0058] Step 1: Collect soil samples from the second area, remove larger particles and vegetation residues, and retain the original soil structure; the process of collecting soil samples: set sampling points at a grid spacing of 8 meters × 8 meters in the target detection area, select 4 representative detection points for sample collection based on the distribution of soil characteristics, and use a sieve or manually remove larger particles and vegetation residues during the collection process to ensure the purity of the sample;

[0059] Step 2: Prepare a double-ring infiltration instrument with an inner ring diameter of 20 cm, an outer ring diameter of 40 cm, and a height of 40 cm. Press the double-ring infiltration instrument vertically into the soil to ensure that the double-ring infiltration instrument is perpendicular to the ground. The vertical insertion depth of the double-ring infiltration instrument is 25 cm. Use a level to ensure that the double rings are perpendicular to the ground. Use soil to tamp the outer wall of the ring to prevent water leakage.

[0060] Step 3: Pour water into the inner and outer rings simultaneously until the water level reaches the mark of 20 cm from the top of the ring and the initial soil moisture is controlled to reach a stable state, and the initial water level is recorded;

[0061] Among them, controlling the initial soil moisture to reach a stable state includes the following steps:

[0062] 31) Inject water several times, with an interval of ten minutes between each injection, and observe the water level changes;

[0063] 32) After the water is fully injected, let it stand for 60 minutes to allow the water to be fully distributed in the soil and reach a more uniform initial moisture state;

[0064] 33) During this period, observe the water levels of the inner and outer rings every 20 minutes to see if the water level records of the inner and outer rings have dropped significantly. If the water level is stable and no longer changes, it means that the initial soil moisture has roughly reached a stable state. When the water level is stable, record the initial water level;

[0065] Step 4: Use the electronic water level sensor to measure the water level of the inner and outer rings every 3 minutes, and record the time and the corresponding water level;

[0066] Step 5: Continue observation after determining that the soil permeability has reached a stable state. When the test is finished, record the final water level data and time. The criteria for determining that the soil permeability has reached a stable state include: water level change monitoring and flow monitoring;

[0067] Water level change monitoring: During the detection process, the water level changes of the inner and outer rings are measured regularly. When the difference in water level changes in two consecutive observations is no more than 5%, it is judged that the soil permeability has stabilized;

[0068] Flow monitoring: record the flow rate per unit time, that is, the amount of water flowing in and out. When the difference between two consecutive flow observation results is less than the preset threshold, it indicates that the soil permeability has reached a stable state;

[0069] Among them, the continued observation includes the following steps:

[0070] 51) After initially judging that the water level change and flow are basically stable, continue to observe for 2.5 hours and record the water level change every 5 minutes;

[0071] 52) During the extended observation period, the electronic water level sensor shall continue to automatically record the water level changes of the inner and outer rings, and the data shall be updated in real time;

[0072] 53) Record the water inflow and outflow at each time point and conduct flow comparison analysis;

[0073] 54) When the water level or flow rate remains within the set threshold and no longer changes significantly during multiple consecutive observation cycles, the observation is terminated and the final data is recorded;

[0074] Step 6: Calculate the permeability of the target soil based on the test data, output the water level change curve, and analyze the trend of permeability change over time; the permeability of the target soil is calculated using the following formula:

[0075]

[0076] Among them, h in and h out are the water level changes of the inner and outer rings respectively, A is the cross-sectional area of ​​the inner ring, t is the time, and L is the length of the soil column.

[0077] In this embodiment, after calculating the data of the four detection points, the soil permeability at different positions in the detection area is obtained as follows: the permeability of detection point 1: K1 = 0.42 cm / min, the permeability of detection point 2: K2 = 0.40 cm / min, the permeability of detection point 3: K3 = 0.45 cm / min, the permeability of detection point 4: K4 = 0.41 cm / min, and the average soil permeability of the area is: K 平均2 =0.42cm / min.

[0078] Embodiment 3: The present invention provides a technical solution: a double-loop soil water permeability detection method, comprising the following steps:

[0079] Step 1: Collect soil samples from the third area, remove larger particles and vegetation residues, and retain the original soil structure; the process of collecting soil samples: set sampling points at a grid spacing of 6 meters × 6 meters in the target detection area, select 5 representative detection points for sample collection based on the distribution of soil characteristics, and use a sieve or manually remove larger particles and vegetation residues during the collection process to ensure the purity of the sample;

[0080] Step 2: Prepare a double-ring infiltration instrument with an inner ring diameter of 18 cm, an outer ring diameter of 35 cm, and a height of 35 cm. Press the double-ring infiltration instrument vertically into the soil to ensure that the double-ring infiltration instrument is perpendicular to the ground. The vertical insertion depth of the double-ring infiltration instrument is 22 cm. Use a level to ensure that the double rings are perpendicular to the ground. Use soil to tamp the outer wall of the ring to prevent water leakage.

[0081] Step 3: Pour water into the inner and outer rings simultaneously until the water level reaches the mark of 18 cm from the top of the ring and control the initial soil moisture to a stable state, and record the initial water level;

[0082] Among them, controlling the initial soil moisture to reach a stable state includes the following steps:

[0083] 31) Inject water several times, with an interval of ten minutes between each injection, and observe the water level changes;

[0084] 32) After the water is fully filled, let it stand for 30 minutes to allow the water to be fully distributed in the soil and reach a more uniform initial moisture state;

[0085] 33) During this period, observe the water levels of the inner and outer rings every 10 minutes to see if the water level records of the inner and outer rings have dropped significantly. If the water level is stable and no longer changes, it means that the initial soil moisture has roughly reached a stable state;

[0086] Step 4: Use the electronic water level sensor to measure the water levels of the inner and outer rings every minute, and record the time and corresponding water level;

[0087] Step 5: Continue observation after determining that the soil permeability has reached a stable state. When the test is finished, record the final water level data and time. The criteria for determining that the soil permeability has reached a stable state include: water level change monitoring and flow monitoring;

[0088] Water level change monitoring: During the detection process, the water level changes of the inner and outer rings are measured regularly. When the difference in water level changes between two consecutive observations is no more than 5%, it is judged that the soil permeability has stabilized;

[0089] Flow monitoring: record the flow rate per unit time, that is, the amount of water flowing in and out. When the difference between two consecutive flow observation results is less than the preset threshold, it indicates that the soil permeability has reached a stable state;

[0090] Among them, the continued observation includes the following steps:

[0091] 51) After initially judging that the water level change and flow are basically stable, continue to observe for 3 hours and record the water level change every 5 minutes;

[0092] 52) During the extended observation period, the electronic water level sensor shall continue to automatically record the water level changes of the inner and outer rings, and the data shall be updated in real time;

[0093] 53) Record the water inflow and outflow at each time point and conduct flow comparison analysis;

[0094] 54) When the water level or flow rate remains within the set threshold and no longer changes significantly during multiple consecutive observation cycles, the observation is terminated and the final data is recorded;

[0095] Step 6: Calculate the permeability of the target soil based on the test data, output the water level change curve, and analyze the trend of permeability change over time; the permeability of the target soil is calculated using the following formula:

[0096]

[0097] Among them, h in and h out are the water level changes of the inner and outer rings respectively, A is the cross-sectional area of ​​the inner ring, t is the time, and L is the length of the soil column.

[0098] In this embodiment, after calculating the data of five detection points, the soil permeability at different positions in the detection area is obtained as follows: the permeability of detection point 1: K1 = 0.28 cm / min, the permeability of detection point 2: K2 = 0.26 cm / min, the permeability of detection point 3: K3 = 0.27 cm / min, the permeability of detection point 4: K4 = 0.29 cm / min, the permeability of detection point 5: K5 = 0.28 cm / min, and the average soil permeability of the area is: K 平均3 =0.28cm / min.

[0099] In this method, by adopting multiple separate water injections with a ten-minute interval between each injection, water can be gradually and evenly introduced into the soil, thus avoiding the situation where a large amount of water injection at one time may cause excessive local water in the soil and insufficient water in other parts. After each water injection, the soil has enough time to absorb water, and the water gradually diffuses in the soil pores, thereby more effectively promoting the uniform distribution of water in the soil. After the water is fully injected, it is left to stand for observation for 30 minutes to 1 hour. This process provides sufficient time for the water to fully penetrate and distribute in the soil. During the standing period, the water in the soil is further diffused and redistributed in the soil pores through gravity, capillary action, etc. Gravity causes the water to penetrate downward, while capillary action causes the water to move horizontally and vertically in the pores, so that the soil reaches a more uniform initial water content. In this way, the water distribution inside the soil is more balanced, reducing the impact of uneven water distribution on the permeability test results. During the water injection and standing process, the water level records of the inner and outer rings are regularly observed. By paying close attention to the changes in the water level, the absorption of water by the soil and the dynamic distribution of water in the soil can be discovered in time. If the water level drops too quickly or fluctuates abnormally, it means that the soil moisture distribution may be uneven or there may be problems such as moisture leakage.

[0100] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double-loop soil permeability detection method, characterized in that: The following steps are involved: S1. Collect soil samples, remove larger particles and vegetation residues, and retain the original soil structure; S2. Press the double-ring infiltrator vertically into the soil to ensure that the double-ring infiltrator is perpendicular to the ground; S3, inject water into the inner ring and the outer ring at the same time, make the water level reach the set scale and control the initial soil moisture to reach a stable state, and record the initial water level; S4. Use an electronic water level sensor to regularly measure the water levels of the inner and outer rings, and record the time and corresponding water level; S5. Continue observation after determining that the soil permeability has reached a stable state. When the test is finished, record the final water level data and time. S6. Calculate the permeability of the target soil based on the test data, output the water level change curve, and analyze the trend of permeability change over time.

2. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S1, the process of collecting soil samples is as follows: in the target detection area, multiple sampling points are set according to a certain grid spacing, and 3-5 representative detection points are selected for sample collection according to the distribution of soil characteristics. During the collection process, larger particles and vegetation residues are removed using a sieve or manually to ensure the purity of the sample.

3. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S2, the vertical insertion depth of the double-ring infiltrator is 20-30 cm.

4. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S3, controlling the initial soil moisture to reach a stable state includes the following steps: S31, inject water several times, each time with an interval of ten minutes, and observe the water level changes; S32. After the water is fully injected, let it stand for 30 to 60 minutes to allow the water to be fully distributed in the soil and reach a more uniform initial moisture state; S33. During this period, regularly observe whether the water level records of the inner and outer rings have dropped significantly. If the water level is stable and no longer changes, it means that the initial soil moisture has roughly reached a stable state.

5. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S5, the criteria for determining whether the soil permeability has reached a stable state include: water level change monitoring and flow rate monitoring; Water level change monitoring: During the detection process, the water level changes of the inner and outer rings are measured regularly. When the difference in water level changes in two consecutive observations is no more than 5%, it is judged that the soil permeability has stabilized; Flow monitoring: record the flow per unit time, that is, the amount of water flowing in and out. When the difference between two consecutive flow observation results is less than the preset threshold, it indicates that the soil permeability has reached a stable state.

6. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S5, the continuous observation includes the following steps: S51. After initially judging that the water level change and flow are basically stable, continue to observe for 2-3 hours and record the water level change every 5 minutes; S52. During the extended observation period, the electronic water level sensor shall continue to be used to automatically record the water level changes of the inner and outer rings, and the data shall be updated in real time; S53, recording the water inlet and outlet at each time point and performing flow rate comparison and analysis; S54. When the water level or flow rate remains within the set threshold value and no longer changes significantly during multiple consecutive observation cycles, the continuous observation is terminated.

7. A double-loop soil water permeability detection method according to claim 1, characterized in that: In step S6, the permeability of the target soil is calculated using the following formula: Among them, h in and h out are the water level changes of the inner and outer rings respectively, A is the cross-sectional area of ​​the inner ring, t is the time, and L is the length of the soil column.

8. A double-loop soil water permeability detection method according to claim 6, characterized in that: In step S6, the output water level change curve graph uses data visualization software to plot the water level change data into a curve graph to intuitively display the trend of permeability change over time.

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