Test method for hydraulic erosion of self-expanding particles under seepage stress coupling

Abstract

The invention discloses a test method for self-expanding particle hydraulic erosion under seepage stress coupling, which can accurately simulate the self-expanding particle hydraulic erosion process under different conditions under seepage stress coupling through the arranged test device, thereby ensuring the reliability and accuracy of the test result. According to the design of the special device, various experimental variables and control parameters including water flow velocity, pressure, temperature, initial conditions of soil samples and the like are considered, and various complex conditions possibly encountered in actual engineering can be reproduced. Various data in the experiment process are collected and recorded in real time through a sensor and a monitoring system, and high precision and high resolution of the data are ensured. Besides, the special test device is further provided with an advanced data acquisition and analysis system, experimental data can be processed and analyzed in real time, abnormal conditions in the experimental process can be quickly recognized and corrected, and the accuracy and reliability of experimental results are further improved.

Description

Technical Field

[0001] The invention belongs to the field of self-expanding particle hydraulic erosion test, and in particular relates to a test method for self-expanding particle hydraulic erosion under seepage stress coupling. Background Art

[0002] In the field of water conservancy engineering, understanding the mechanism of hydraulic erosion of self-expanding particles under seepage stress coupling is crucial for the prevention of geological disasters and the protection of engineering safety. Expansive soil is a special type of soil that is prone to volume expansion and contraction under the action of water. The water adsorption and desorption of minerals such as montmorillonite and illite are the main reasons for its volume change. When expansive soil is eroded by water flow, the scouring effect of the water flow will cause the movement and rearrangement of particles inside the soil, thereby aggravating the erosion and damage of the soil and posing a threat to engineering safety.

[0003] Under such circumstances, conducting experimental research on hydraulic erosion of self-expanding particles under seepage stress coupling has important scientific and engineering significance. At present, the research on hydraulic erosion of self-expanding particles under seepage stress coupling requires a lot of experimental verification to reveal the erosion mechanism, assess the risk, and propose corresponding protective measures. However, traditional experimental methods often have problems such as complex operation, inaccurate data acquisition, and difficulty in reproducing experimental results.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a test method for hydraulic erosion of self-expanding particles under seepage stress coupling, thereby solving the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0007] A test method for hydraulic erosion of self-expanding particles under seepage stress coupling, using test equipment to complete the hydraulic erosion test, the test device includes a main test tank, a water pump, a water inlet valve, a pressure gauge, an axial loading system, a pressure gauge a, a pressure gauge b, a nylon tube, a bottom plate and an auxiliary system, the auxiliary system includes a water pump control system, a pressure control system, a temperature control system and a data acquisition system, the water pump is connected to the water inlet pipe of the test tank through the water inlet valve, a pressure gauge is installed on the water inlet pipe to monitor the water flow pressure, an axial loading system is installed on the top of the test tank, the water pressure on the top of the sample is measured through the pressure gauge b, a pressure gauge a is installed on the side of the test tank, connected to the bottom plate through a nylon tube, the water pressure on the side of the sample is measured and water is guided out, the bottom plate is located at the bottom of the test tank, supports the entire device, and is connected to a water collecting tank through a nylon tube to collect the outflowing water, is located on the rightmost side of the device, and the water collecting tank is connected to the bottom plate through a nylon tube to collect the water flowing out of the test tank to prevent water loss;

[0008] The steps for conducting a test using the test device are:

[0009] S1: Selecting expansive granular soil samples, and drying, sieving and mixing the expansive granular soil samples;

[0010] S2: Adjust the flow, pressure and temperature parameters through the auxiliary system to simulate the hydraulic erosion process under different conditions;

[0011] S3: placing the pretreated granular soil sample in the test tank, starting the water pump, allowing the fluid to flow through the test tank and begin to erode the granular soil sample;

[0012] S4: Use sensors and data acquisition systems to monitor key parameters during the test in real time;

[0013] S5: Statistical analysis and processing of key parameters to obtain erosion rate and particle movement law;

[0014] S6: Based on the obtained erosion rate and particle movement law, a mathematical model was established to further study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling, and the corresponding test results were obtained;

[0015] S7: Compare and verify the test results with the actual engineering conditions to verify the accuracy and reliability of the test methods, and formulate corresponding geological disaster protection measures and engineering design recommendations based on the test results.

[0016] Optionally, the expanded granular soil sample is processed by drying, screening and mixing methods, and the specific steps include: selecting a soil sample with expanded particles and performing a drying process to remove moisture from the soil sample; then removing oversized or undersized particles through a screening process; and finally, mixing soil samples from different sources or at different processing stages through a mixing process.

[0017] Optionally, the steps of adjusting the flow, pressure and temperature parameters through the auxiliary system to simulate the hydraulic erosion process under different conditions are:

[0018] Step S1: setting the required water flow rate through the flow regulation function of the water pump, and the water pump control system monitors the water flow rate in real time;

[0019] Step S2: A flow sensor is installed at the water pump, and the flow sensor is used to monitor and feedback the change of water flow speed;

[0020] Step S3: Set the required water flow pressure through the pressure regulating valve, and use the pressure sensor to monitor the change of water flow pressure in real time; then, feed back the preset data to the pressure control system, and the pressure control system adjusts the pressure in real time according to the preset pressure to simulate different water flow impact forces.

[0021] Optionally, the steps for using sensors and data acquisition systems to monitor key parameters during the test in real time are:

[0022] Sensors are placed in the test tank to monitor the soil erosion depth and particle movement speed in real time;

[0023] After the sensor receives the data, it will transmit the data collected by the sensor to the data acquisition system for real-time recording and storage;

[0024] The data acquisition system analyzes the obtained data and performs preliminary processing on the collected data to obtain information on erosion rate and particle movement trajectory.

[0025] Optionally, the data acquisition system analyzes the acquired data and performs preliminary processing on the acquired data. The acquisition logic for acquiring the erosion rate and particle motion trajectory information is as follows:

[0026] By integrating the data of erosion depth changing with time, the change of erosion depth per unit time is calculated to obtain the erosion rate. Based on the water velocity and flow rate, combined with the change of erosion depth, the erosion volume per unit time is calculated and further converted into erosion rate. The expression is: Where A is the cross-sectional area of ​​the specimen, Δd(t) is the change in erosion depth, and v e is the erosion rate, Δt is the time change, d(t) is the erosion depth, and Q is the flow rate;

[0027] According to the particle motion speed and position data, the trajectory reconstruction algorithm is used to reconstruct the particle motion trajectory, and the reconstructed particle motion trajectory is smoothed to remove noise and anomalies in the trajectory to obtain a continuous particle motion trajectory. The motion speed, acceleration and path length are extracted from the particle motion trajectory to analyze the particle motion law;

[0028] The calculation and analysis results are visualized, including erosion rate curves and particle motion trajectory diagrams.

[0029] Optionally, obtain the trajectory r (t) The expressions for obtaining the particle's velocity v(t) and acceleration a(t) are:

[0030]

[0031] in, is the particle position vector r (t) The first derivative with respect to time t represents the velocity vector; r (t) is the particle position vector after smoothing, is the first-order derivative of position x(t) with respect to time t, representing the velocity component in the x direction, is the first-order derivative of position y(t) with respect to time t, representing the velocity component in the y direction, The first derivative of position z(t) with respect to time t represents the velocity component in the z direction, where t is time; is the first-order derivative of the velocity vector v(t) with respect to time t, representing the acceleration vector, is the particle position vector r (t) The second derivative with respect to time t represents the acceleration vector. is the second-order derivative of position x(t) with respect to time t, representing the acceleration component in the x direction, is the second-order derivative of position y(t) with respect to time t, representing the acceleration component in the y direction, is the second derivative of position z(t) with respect to time t, representing the acceleration component in the z direction.

[0032] The mathematical model is established based on the experimental results to deeply study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling. The steps are as follows:

[0033] Based on the erosion rate and particle movement law obtained by statistical analysis, a mathematical model of hydraulic erosion of self-expanding particles under seepage stress coupling is constructed;

[0034] Through computer simulation technology, the constructed mathematical model is verified and optimized, and the optimized mathematical model is applied to hydraulic erosion simulation under different conditions to study the erosion mechanism and law of self-expanding particles under seepage stress coupling.

[0035] Optionally, laboratory test results E lab (t) and hydraulic erosion in actual projects field (t) Compare and verify the reliability of test methods and data and identify potential geological disaster risks in real projects based on comparative analysis results.f , whose expression is: Among them, R f >1 indicates the existence of geological disaster risk; finally, based on the analysis results and mathematical models, specific geological disaster protection measures and engineering design suggestions are proposed.

[0036] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art. Of course, any product implementing the present invention does not necessarily need to achieve all the advantages described below at the same time:

[0037] The present invention can accurately simulate the hydraulic erosion process of self-expanding particles under seepage stress coupling under different conditions by designing a special test device, thereby ensuring the reliability and accuracy of the test results. The design of this special device takes into account a variety of experimental variables and control parameters, including water flow velocity, pressure, temperature and initial conditions of soil samples, and can reproduce various complex situations that may be encountered in actual engineering. Through sensors and monitoring systems, various data during the experiment are collected and recorded in real time, ensuring high precision and high resolution of the data. In addition, the special test device is also equipped with an advanced data acquisition and analysis system, which can process and analyze the experimental data in real time, quickly identify and correct abnormal situations during the experiment, and further improve the accuracy and reliability of the experimental results.

[0038] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0040] In the figure:

[0041] Figure 1 It is a flowchart of the test method;

[0042] Figure 2 A cross-sectional diagram of the test device.

[0043] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0044] 1. Water pump; 2. Water inlet valve; 3. Pressure gauge; 4. Axial loading system; 5. Pressure measuring tube a; 6. Pressure measuring tube b; 7. Nylon tube; 8. Bottom plate.

[0045] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0046] The present invention will now be described in further detail with reference to the accompanying drawings.

[0047] See also Figure 1-2 As shown, in this embodiment, a test method for hydraulic erosion of self-expanding particles under seepage stress coupling is provided, and a test device is used to complete the hydraulic erosion test. The test device includes a main test tank, a water pump 1, a water inlet valve 2, a pressure gauge 3, an axial loading system 4, a pressure measuring tube a5, a pressure measuring tube b6, a nylon tube 7, a bottom plate 8 and an auxiliary system. The auxiliary system includes a water pump 1 control system, a pressure control system, a temperature control system and a data acquisition system. The water pump 1 is connected to the water inlet pipe of the test tank through the water inlet valve 2. A pressure gauge 3 is installed on the water inlet pipe to monitor the water flow pressure. The axial loading system 4 is installed on the top of the test tank to measure the water pressure on the top of the sample through the pressure measuring tube b6. A pressure measuring tube a5 is installed on the side of the test tank and is connected to the bottom plate 8 through the nylon tube 7 to measure the water pressure on the side of the sample and guide the water out. The bottom plate 8 is located at the bottom of the test tank, supports the entire device, and is connected to the water collecting tank through the nylon tube 7 to collect the outflowing water. It is located on the far right side of the device. The water collecting tank is connected to the bottom plate 8 through the nylon tube 7 to collect the water flowing out of the test tank to prevent water loss.

[0048] The steps for conducting a test using the test device are:

[0049] S1: Selecting expansive granular soil samples, and drying, sieving and mixing the expansive granular soil samples;

[0050] S2: Adjust the flow, pressure and temperature parameters through the auxiliary system to simulate the hydraulic erosion process under different conditions;

[0051] S3: placing the pretreated granular soil sample in the test tank, starting the water pump, allowing the fluid to flow through the test tank and begin to erode the granular soil sample;

[0052] S4: Use sensors and data acquisition systems to monitor key parameters during the test in real time;

[0053] S5: Statistical analysis and processing of key parameters to obtain erosion rate and particle movement law;

[0054] S6: Based on the obtained erosion rate and particle movement law, a mathematical model was established to further study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling, and the corresponding test results were obtained;

[0055] S7: Compare and verify the test results with the actual engineering conditions to verify the accuracy and reliability of the test methods, and formulate corresponding geological disaster protection measures and engineering design recommendations based on the test results.

[0056] It should be noted that: by selecting expansive granular soil samples and carrying out drying, screening and mixing treatments, using the auxiliary system to adjust the flow, pressure and temperature parameters to simulate the hydraulic erosion process under different conditions, the pretreated granular soil samples are placed in the test tank, the water pump is started to carry out the erosion experiment, and the key parameters are monitored in real time using sensors and data acquisition systems. The data are statistically analyzed and processed to obtain the erosion rate and particle movement law. Based on this, a mathematical model is established, and the hydraulic erosion mechanism and law of self-expanding particles under seepage stress coupling are deeply studied. The test results are obtained, and they are compared and verified with the actual engineering conditions to ensure the accuracy and reliability of the test method.

[0057] By designing a special test device, the hydraulic erosion process of self-expanding particles under seepage stress coupling under different conditions can be accurately simulated to ensure the reliability and accuracy of the test results. The design of this special device takes into account a variety of experimental variables and control parameters, including water flow velocity, pressure, temperature and initial conditions of soil samples, and can reproduce various complex situations that may be encountered in actual engineering. Through sensors and monitoring systems, various data during the experiment are collected and recorded in real time, ensuring high accuracy and high resolution of the data. In addition, the special test device is also equipped with an advanced data acquisition and analysis system, which can process and analyze the experimental data in real time, quickly identify and correct abnormal situations during the experiment, and further improve the accuracy and reliability of the experimental results.

[0058] In this embodiment, the expanded granular soil sample is processed by drying, screening and mixing methods, and the specific steps include: selecting a soil sample with expanded particles and performing a drying process to remove moisture from the soil sample; then removing oversized or undersized particles through a screening process, and finally mixing soil samples from different sources or at different processing stages through a mixing process. Drying can remove moisture from the soil sample, avoid the influence of changes in moisture content on the experimental results, and improve the precision and accuracy of the experimental processing. Through the screening process, oversized or undersized particles can be removed, the particle size distribution of the sample can be optimized, and the quality of the sample and the consistency of the experimental conditions can be ensured.

[0059] It should be noted that processing the expanded granular soil samples by drying, screening and mixing methods can not only improve the uniformity and consistency of the experimental samples, remove moisture and unqualified particles, and optimize the sample quality, but also make the sample characteristics uniform, reduce experimental errors, and improve the representativeness and applicability of the experimental results.

[0060] In this embodiment, the steps of adjusting the flow rate, pressure and temperature parameters by the auxiliary system to simulate the hydraulic erosion process under different conditions are as follows:

[0061] Step S1: The required water flow rate is set through the flow regulation function of the water pump, and the water pump control system monitors the water flow rate in real time; through the flow regulation function of the water pump, the required water flow rate can be accurately set, and the water pump control system monitors and adjusts the water flow rate in real time to ensure the stability and consistency of the experimental conditions.

[0062] Step S2: A flow sensor is installed at the water pump, and the flow sensor is used to monitor and feedback changes in water flow velocity; installing a flow sensor at the water pump can monitor changes in water flow velocity in real time and feed back data to the control system, so as to adjust the water flow velocity in time to ensure the real-time and dynamic adjustment capabilities of the experimental conditions.

[0063] Step S3: Set the required water flow pressure through the pressure regulating valve, and use the pressure sensor to monitor the change of water flow pressure in real time; then, feed back the preset data to the pressure control system, and the pressure control system adjusts the pressure in real time according to the preset pressure to simulate different water flow impact forces. Set the required water flow pressure through the pressure regulating valve, and use the pressure sensor to monitor and feedback the change of water flow pressure in real time. The control system adjusts the pressure in real time according to the preset pressure, which can simulate different water flow impact forces and meet the diverse experimental needs.

[0064] It should be noted that: the water flow rate is set through the flow adjustment function of the water pump, the flow sensor monitors and feedbacks the change of water flow rate in real time, the pressure regulating valve sets the water flow pressure and monitors and feedbacks the pressure change in real time through the pressure sensor, and the control system adjusts the pressure in real time to simulate different water flow impact forces. These steps not only achieve the goal of accurately controlling the water flow speed and pressure, ensuring the stability and consistency of the experimental conditions, but also improve the accuracy and stability of the experimental data and reduce manual intervention.

[0065] In this embodiment, the steps of using sensors and a data acquisition system to monitor key parameters in real time during the test are as follows:

[0066] Sensors are placed in the test tank to monitor the soil erosion depth and particle movement speed in real time; By placing sensors in the test tank, the soil erosion depth and particle movement speed can be monitored in real time, and data can be obtained in real time to ensure the timeliness and accuracy of the experimental data. The data collected by the sensor will be immediately transmitted to the data acquisition system, and recorded and stored in real time to avoid data loss and ensure the integrity and reliability of the data.

[0067] Through sensors and monitoring devices, key parameters in the test process, such as soil erosion depth, particle movement speed, etc., are monitored in real time to obtain accurate test data, providing a reliable basis for subsequent analysis and research. The application of modern sensor technology and high-precision monitoring devices enables accurate and continuous monitoring of key parameters during the test. Sensors include but are not limited to laser rangefinders, high-definition camera systems, accelerometers and pressure sensors, which can fully capture and record every subtle change in the soil erosion process. The data collected by the sensors is transmitted to the central data processing system in real time through a high-speed data transmission interface to ensure the real-time and integrity of the data.

[0068] The monitoring system can automatically record and store the changes in erosion depth and particle movement speed at each moment during the experiment, and perform preliminary processing on the raw data through data processing algorithms, such as denoising, filtering and error correction, to improve the accuracy of the data. The characteristics of real-time monitoring and data recording not only help to promptly discover and correct abnormal situations in the experiment, but also enable detailed time series analysis after the experiment, helping researchers understand the dynamic changes of the erosion process and the laws of particle movement.

[0069] After the sensor receives the data, it will transmit the data collected by the sensor to the data acquisition system for real-time recording and storage; the data acquisition system analyzes and preliminarily processes the received data, and can quickly obtain erosion rate and particle movement trajectory information, providing basic data for subsequent detailed analysis and improving work efficiency.

[0070] The data acquisition system analyzes the obtained data and performs preliminary processing on the collected data to obtain information on erosion rate and particle movement trajectory.

[0071] It should be noted that by arranging sensors in the test tank for real-time monitoring, data transmission and storage, data analysis and preliminary processing, not only the real-time acquisition and recording of experimental data is achieved, ensuring the integrity and reliability of the data, but also the key parameters can be accurately obtained, supporting multivariate complex analysis, reducing human intervention and errors, and improving data credibility and analysis efficiency.

[0072] In this embodiment, the data acquisition system analyzes the acquired data and performs preliminary processing on the acquired data. The acquisition logic for acquiring the erosion rate and particle motion trajectory information is as follows:

[0073] By integrating the data of erosion depth changing with time, the change of erosion depth per unit time is calculated to obtain the erosion rate. Based on the water velocity and flow rate, combined with the change of erosion depth, the erosion volume per unit time is calculated and further converted into erosion rate. The expression is: Where A is the cross-sectional area of ​​the specimen, Δd(t) is the change in erosion depth, and v e is the erosion rate, Δt is the time change, d(t) is the erosion depth, and Q is the flow rate;

[0074] According to the particle motion speed and position data, the trajectory reconstruction algorithm is used to reconstruct the particle motion trajectory, and the reconstructed particle motion trajectory is smoothed to remove noise and anomalies in the trajectory, and a continuous particle motion trajectory is obtained. The motion speed, acceleration and path length are extracted from the particle motion trajectory to analyze the particle motion law; the erosion rate and erosion volume are calculated by the time integration method to ensure the high accuracy and reliability of the data, reduce experimental errors, and improve the credibility of the results. The trajectory is reconstructed and smoothed using particle motion data to achieve dynamic monitoring and real-time analysis of particle motion and provide real-time data support.

[0075] The calculation and analysis results are visualized, including erosion rate curves and particle motion trajectory diagrams. By extracting particle motion speed, acceleration, and path length, the particle motion law is comprehensively analyzed and the particle motion mechanism is deeply understood.

[0076] In this embodiment, the trajectory r (t) The expressions for obtaining the particle's velocity v(t) and acceleration a(t) are:

[0077]

[0078] in, is the particle position vector r (t) The first derivative with respect to time t represents the velocity vector; r (t) is the particle position vector after smoothing, is the first-order derivative of position x(t) with respect to time t, representing the velocity component in the x direction, is the first-order derivative of position y(t) with respect to time t, representing the velocity component in the y direction, The first derivative of position z(t) with respect to time t represents the velocity component in the z direction, where t is time; is the first-order derivative of the velocity vector v(t) with respect to time t, representing the acceleration vector, is the particle position vector r (t) The second derivative with respect to time t represents the acceleration vector. is the second-order derivative of position x(t) with respect to time t, representing the acceleration component in the x direction, is the second-order derivative of position y(t) with respect to time t, representing the acceleration component in the y direction, It is the second-order derivative of position z(t) with respect to time t, representing the acceleration component in the z direction. Through continuous monitoring of particle position and data processing, the speed and acceleration are calculated using mathematical derivatives to ensure high precision and accuracy of the results; for example, in the monitoring of particle flow in a river channel, the motion state of the particles can be accurately calculated, thereby better predicting the erosion and deposition process.

[0079] By calculating the velocity and acceleration in three-dimensional space, the motion state of particles in all directions is comprehensively analyzed, providing more comprehensive motion characteristic data. When studying debris flow movement, three-dimensional motion analysis can fully understand the motion trajectory and dynamic characteristics of particles in debris flow, providing detailed data support for prevention and control measures.

[0080] In this embodiment, a mathematical model is established based on the experimental results to deeply study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling, and the steps for obtaining the model are as follows:

[0081] According to the erosion rate and particle movement law obtained by statistical analysis, a mathematical model of hydraulic erosion of self-expanding particles under seepage stress coupling is constructed; by constructing a mathematical model based on experimental results, it is ensured that the model can truly reflect the experimental data and improve the accuracy and reliability of the model. For example, in the anti-seepage research of a reservoir dam, the model constructed using laboratory data accurately predicted the key positions and rates of seepage erosion, thus providing a scientific basis for the reinforcement of the dam.

[0082] Through computer simulation technology, the constructed mathematical model is verified and optimized, and the optimized mathematical model is applied to hydraulic erosion simulation under different conditions to study the erosion mechanism and law of self-expanding particles under seepage stress coupling. Through computer simulation technology, the mathematical model is verified and optimized, and the model parameters and structure can be continuously adjusted to improve the prediction ability and applicability of the model. For example, in an erosion risk assessment of an urban underground pipeline network, the model optimized by simulation technology successfully identified several high-risk areas, and protective treatment was carried out in advance to avoid potential pipeline network damage.

[0083] Applying the optimized mathematical model to hydraulic erosion simulation under different conditions can dynamically simulate and predict the erosion process in actual projects and provide real-time data support. For example, in the stability study of a highway slope, the optimized mathematical model was applied to dynamically simulate the erosion process of the slope under different rainfall conditions, guiding the slope protection design and emergency treatment measures.

[0084] In this embodiment, the laboratory test results E lab (t) and hydraulic erosion in actual projects field(t) Compare and verify the reliability of test methods and data and identify potential geological disaster risks in real projects based on comparative analysis results. f , whose expression is: Among them, R f >1 indicates the existence of geological disaster risk; finally, based on the analysis results and mathematical models, specific geological disaster protection measures and engineering design suggestions are proposed.

[0085] It should be noted that by comparing the laboratory test results with the data in the actual project, the accuracy and reliability of the experimental method can be verified to ensure that the experimental data can truly reflect the actual situation in the project. This helps to eliminate the differences between the experimental conditions and the field conditions and improve the credibility of the experimental results.

[0086] By using the comparative analysis results, the potential geological disaster risks in actual projects can be identified. f When it is greater than 1, it indicates the presence of geological disaster risk. By identifying risks early, preventive and response measures can be taken in time to avoid disasters.

[0087] The present invention is not limited to the above-mentioned embodiments. Anyone should be aware that any structural changes made under the enlightenment of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention. The technology, shape, and structural parts not described in detail in the present invention are all well-known technologies.

Claims

1. A test method for hydraulic erosion of self-expanding particles under seepage stress coupling, using a test device to complete the hydraulic erosion test, characterized in that: The test device comprises a main test tank, a water pump (1), a water inlet valve (2), a pressure gauge (3), an axial loading system (4), a pressure measuring tube a (5), a pressure measuring tube b (6), a nylon tube (7), a bottom plate (8) and an auxiliary system. The auxiliary system comprises a water pump (1) control system, a pressure control system, a temperature control system and a data acquisition system. The water pump (1) is connected to the water inlet pipe of the test tank through the water inlet valve (2). A pressure gauge (3) is installed on the water inlet pipe to monitor the water flow pressure. An axial loading system (4) is installed on the top of the test tank. The loading system (4) measures the water pressure on the top of the sample through the pressure measuring tube b (6). A pressure measuring tube a (5) is installed on the side of the test tank and is connected to the bottom plate (8) through a nylon tube (7) to measure the water pressure on the side of the sample and drain the water. The bottom plate (8) is located at the bottom of the test tank, supports the entire device, and is connected to a water collecting tank through a nylon tube (7) to collect the outflowing water. The bottom plate (8) is located on the far right side of the device. The water collecting tank is connected to the bottom plate (8) through a nylon tube (7) to collect the water flowing out of the test tank to prevent water loss. The steps for conducting a test using the test device are: S1: Selecting expansive granular soil samples, and drying, sieving and mixing the expansive granular soil samples; S2: Adjust the flow, pressure and temperature parameters through the auxiliary system to simulate the hydraulic erosion process under different conditions; S3: placing the pretreated granular soil sample in the test tank, starting the water pump, allowing the fluid to flow through the test tank and begin to erode the granular soil sample; S4: Use sensors and data acquisition systems to monitor key parameters during the test in real time; S5: Statistical analysis and processing of key parameters to obtain erosion rate and particle movement law; S6: Based on the obtained erosion rate and particle movement law, a mathematical model is established to further study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling, and the corresponding test results are obtained; S7: Compare and verify the test results with the actual engineering conditions to verify the accuracy of the test method, and formulate corresponding geological disaster protection measures and engineering design recommendations based on the test results.

2. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 1, characterized in that: The expanded particle soil samples are processed by drying, screening and mixing methods. The specific steps include: selecting soil samples with expanded particles and performing drying treatment to remove moisture in the soil samples; then removing the screened particles through a screening process; and finally, mixing soil samples from different sources or at different processing stages through a mixing process.

3. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 1, characterized in that: The steps of adjusting the flow, pressure and temperature parameters through the auxiliary system to simulate the hydraulic erosion process under different conditions are as follows: Step S1: The required water flow rate is set by the flow regulation function of the water pump, and the water pump control system monitors the water flow rate in real time; Step S2: A flow sensor is installed at the water pump, and the flow sensor is used to monitor and feedback the change of water flow speed; Step S3: Set the required water flow pressure through the pressure regulating valve, and use the pressure sensor to monitor the change of water flow pressure in real time; then, feed back the preset data to the pressure control system, and the pressure control system adjusts the pressure in real time according to the preset pressure to simulate different water flow impact forces.

4. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 1, characterized in that: The steps to use sensors and data acquisition systems to monitor key parameters during the test in real time are: Sensors are placed in the test tank to monitor the soil erosion depth and particle movement speed in real time; After the sensor receives the data, it will transmit the data collected by the sensor to the data acquisition system for real-time recording and storage; The data acquisition system analyzes the obtained data and performs preliminary processing on the collected data to obtain information on erosion rate and particle movement trajectory.

5. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 1, characterized in that: The data acquisition system analyzes the acquired data and performs preliminary processing on the acquired data. The acquisition logic of the erosion rate and particle motion trajectory information is as follows: By integrating the data of erosion depth changing with time, the change of erosion depth per unit time is calculated to obtain the erosion rate. Based on the water velocity and flow rate, combined with the change of erosion depth, the erosion volume per unit time is calculated, which is further converted into erosion rate. The expression is: Where A is the cross-sectional area of ​​the specimen, Δd(t) is the change in erosion depth, and v e is the erosion rate, Δt is the time change, d(t) is the erosion depth, and Q is the flow rate; According to the particle motion speed and position data, the trajectory reconstruction algorithm is used to reconstruct the particle motion trajectory, and the reconstructed particle motion trajectory is smoothed to remove noise and anomalies in the trajectory to obtain a continuous particle motion trajectory. The motion speed, acceleration and path length are extracted from the particle motion trajectory to analyze the particle motion law; The calculation and analysis results are visualized, including erosion rate curves and particle motion trajectory diagrams.

6. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 5, characterized in that: By obtaining the trajectory r (t) The expressions for obtaining the particle's velocity v(t) and acceleration a(t) are: in, is the particle position vector r (t) The first derivative with respect to time t represents the velocity vector; r (t) is the particle position vector after smoothing, is the first-order derivative of position x(t) with respect to time t, representing the velocity component in the x direction, is the first-order derivative of position y(t) with respect to time t, representing the velocity component in the y direction, The first derivative of position z(t) with respect to time t represents the velocity component in the z direction, where t is time; is the first-order derivative of the velocity vector v(t) with respect to time t, representing the acceleration vector, is the particle position vector r (t) The second derivative with respect to time t represents the acceleration vector, is the second-order derivative of position x(t) with respect to time t, representing the acceleration component in the x direction, is the second-order derivative of position y(t) with respect to time t, representing the acceleration component in the y direction, is the second derivative of position z(t) with respect to time t, representing the acceleration component in the z direction.

7. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 5, characterized in that: The mathematical model is established based on the experimental results to deeply study the mechanism and law of hydraulic erosion of self-expanding particles under seepage stress coupling. The steps are as follows: Based on the erosion rate and particle movement law obtained by statistical analysis, a mathematical model of hydraulic erosion of self-expanding particles under seepage stress coupling is constructed; Through computer simulation technology, the constructed mathematical model is verified and optimized, and the optimized mathematical model is applied to hydraulic erosion simulation under different conditions to study the erosion mechanism and law of self-expanding particles under seepage stress coupling.

8. The test method for hydraulic erosion of self-expanding particles under seepage stress coupling according to claim 7, characterized in that: The laboratory test results E lab (t) and hydraulic erosion in actual projects field (t) Compare and verify the reliability of test methods and data and identify potential geological disaster risks in real projects based on comparative analysis results. f , whose expression is: Among them, R f >1 indicates the existence of geological disaster risk; finally, based on the analysis results and mathematical models, specific geological disaster protection measures and engineering design suggestions are proposed.

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