Method and system for analyzing migration of particles in loess under seepage action

Abstract

The invention discloses a method and system for analyzing migration of particles in loess under the action of seepage, and relates to the technical field of loess analysis, the method comprises the following steps: carrying out electron microscope scanning and particle size analysis on a soil sample to obtain particle distribution data and images in a soil body before seepage; performing a seepage test on the soil sample through nuclear magnetic resonance, and monitoring changes of water filling pores and water content of the soil sample in real time in a seepage process; after the seepage is finished, acquiring particle distribution data and images in the soil body after the seepage through the electron microscope scanning and particle analysis equipment again; processing the particle distribution images before and after seepage to generate a macroscopic image comparison result; and determining the particle migration rule of the soil sample under the seepage action by combining data comparison results of micro-pores, particle distribution, macroscopic particle migration images and the like before and after the soil sample. The loess internal structure change process in the seepage process can be monitored in real time from the microscopic-macroscopic scale, and the loess internal particle migration process in the seepage process is truly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of loess analysis, and in particular relates to a method and system for analyzing the migration of particles inside loess under seepage. Background Art

[0002] Loess, a typical porous medium, has a well-developed internal pore structure and is rich in clay minerals and fine particles. Loess has a loose microstructure and numerous joints and fissures on a macroscale. This leads to significant structural changes and a sharp drop in strength when it comes into contact with water, which can trigger a series of geological hazards such as loess collapse, ground subsidence, and ground fissures. Years of research have shown that loess particles migrate when it comes into contact with water, causing structural collapse and, in turn, macroscopic ground or slope failure. However, the particle migration process and mechanism of action have been largely unexplained. This is primarily because loess particle migration and structural collapse are multi-scale dynamic processes, involving changes in seepage channels at the microscale that induce macroscopic crack expansion, and microscopic particle migration that causes macroscopic ground or slope collapse. Furthermore, these processes are dynamic, not static, evolutionary processes.

[0003] With the development of science and technology in recent years, many high-precision equipment have been introduced into the geotechnical industry, and many studies have been further brought into the microscopic world. Engineering geologists have also further seen the microscopic action mechanisms of these processes. For example, scanning electron microscopy and quantitative microstructural analysis can reveal the relationship between particle migration and soil anisotropy and pore connectivity, supporting multi-scale (e.g., aggregate-to-single-particle) structural analysis. However, they can only characterize static microstructures and have difficulty capturing dynamic migration processes. Dynamic triaxial testing and particle flow numerical simulation can reproduce the mechanical mechanisms of particle migration under load and quantify the effects of parameters such as porosity and stiffness on the migration threshold. However, numerical models rely on parameter calibration (e.g., friction factor, bond strength), and their accuracy is limited by experimental data, making them of limited applicability to heterogeneous loess. Laser particle size analyzers can quickly and accurately measure particle size distribution and support analysis of particles over a wide range (0.1μm–2mm). However, they cannot distinguish the effects of particle morphology (e.g., sphericity, major / minor axis) on migration and have stringent requirements for the dispersion of samples with high clay content. X-CT scanning technology can obtain three-dimensional pore networks and particle migration trajectories, dynamically visualizing particle migration paths and blockage effects. However, small-scale models may not fully reflect actual engineering conditions. Therefore, it is urgent to explore the combination of multiple methods and technologies, combine the characteristics of loess porous media, and propose a multi-scale particle migration monitoring method suitable for the loess seepage process, so as to more realistically reveal the dynamic mechanism of particle migration in the loess seepage process. Summary of the Invention

[0004] The present invention provides a method and system for analyzing the migration of particles inside loess under seepage, aiming to solve the problem that the current analysis method of the particle migration process under loess seepage is not comprehensive and accurate enough, and cannot comprehensively consider the changes and distribution of particles, resulting in the reliability of the analysis results needing to be further improved.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for analyzing the migration of particles in loess under seepage, comprising the following steps: S1. Pre-treating the soil sample to prepare a reshaped soil sample; S2. Perform electron microscope scanning and particle analysis on the reshaped soil sample to obtain the particle distribution image and particle size distribution data of the reshaped soil sample before seepage; S3. Conduct a seepage test on the reshaped soil sample to monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil sample in real time during the seepage process, and obtain microscopic pore characteristic data of the reshaped soil sample during the seepage process; S4. Scanning electron microscope (SEM) and particle analysis are performed again on the reshaped soil sample after seepage to obtain the particle distribution image and particle size distribution data after seepage, respectively; S5. Binarize the particle distribution images of the reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; S6. Comparing the particle size distribution data of the reshaped soil sample before and after seepage, quantitatively analyzing the migration pattern of the particle size of the reshaped soil sample, and generating quantitative data of particle redistribution; S7. Combine the macroscopic seepage data and microscopic pore characteristic data of the reshaped soil sample during the seepage process obtained by the nuclear magnetic resonance equipment, the quantitative data of particle redistribution obtained by the electron microscope scanning equipment and the particle analysis equipment, and the intuitive image comparison results of particle migration to comprehensively determine the migration law of the reshaped soil sample particles under the action of seepage.

[0006] In some embodiments, in S1, pre-processing the soil sample includes: screening, drying, water spraying, and compacting the soil sample according to a preset moisture content and dry density.

[0007] In some embodiments, in S2, before the electron microscope scanning test, the reshaped soil sample is subjected to gold spraying treatment using an ion sputtering coating machine.

[0008] Furthermore, in S2, a scanning electron microscope is used to perform high-resolution scanning on the soil sample to obtain a reshaped image microstructure image; the reshaped image microstructure image is processed to obtain a particle distribution image of the reshaped soil sample before seepage; a laser particle size analyzer is used to perform particle size analysis on the reshaped soil sample to obtain particle size grading data.

[0009] In some embodiments, in S3, during the seepage test of the reshaped soil sample using the nuclear magnetic resonance module, the magnetic field intensity of the nuclear magnetic resonance seepage test is controlled to a constant value, the pulse frequency range is controlled to be 1-30 MHz, and the reshaped soil sample remains undisturbed during the seepage process.

[0010] Furthermore, in S3, the Nuclear Magnetic Resonance (NMR) module adjusts different flow rates through a constant-speed pump to simulate the migration of reshaped soil sample particles under different seepage conditions and record the T2 spectra and water-filled pore size distribution curves at different flow rates.

[0011] In some embodiments, in S5, the particle distribution image of the reshaped soil sample before and after seepage is binarized using Image-Pro Plus (IPP) software.

[0012] In some embodiments, in S6, quantitatively analyzing the migration pattern of the particle size of the reshaped soil sample and generating quantitative data of particle redistribution includes: calculating the particle size changes of the reshaped soil sample D10, D30, and D60, and generating a gradation curve based on the particle size gradation data to quantify the particle migration effect.

[0013] Furthermore, in S6, a laser particle size analyzer is used to analyze the particle size of the remolded soil samples before and after seepage; an electronic balance is used to weigh the mass of particles of different remolded soil sample sizes to obtain quantitative data on the redistribution of remolded soil sample particles.

[0014] The present invention also provides a system for analyzing the migration of particles inside loess under seepage, the system comprising a nuclear magnetic resonance module, an electron microscope scanning module, an image processing module, and a particle analysis module, wherein: The nuclear magnetic resonance module is used to conduct a seepage test on the reshaped soil sample through the nuclear magnetic resonance module, monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil sample in real time during the seepage process, and obtain the microscopic pore characteristic data of the reshaped soil sample during the seepage process; Nuclear Magnetic Resonance Module: Used to conduct seepage tests on reshaped soil samples through the Nuclear Magnetic Resonance (NMR) module, monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil samples in real time during the seepage process, and obtain macroscopic seepage data and microscopic pore characteristic data of the reshaped soil samples during the seepage process; Electron microscope scanning module: used to perform electron microscope scanning and particle analysis on the reshaped soil sample, respectively obtaining the particle distribution image and particle size gradation data of the reshaped soil sample before seepage; The reshaped soil samples after seepage were scanned again with an electron microscope and subjected to particle analysis to obtain particle distribution images and particle size distribution data after seepage respectively. Image processing module: used to perform binary processing on the particle distribution images of reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; Particle analysis module: used to compare the particle size distribution data of reshaped soil samples before and after seepage through the particle analysis module, quantitatively analyze the migration law of the particle size of the reshaped soil samples, and generate quantitative data of particle redistribution Migration analysis module: It is used to comprehensively determine the migration law of reshaped soil sample particles under seepage by combining the microscopic pore characteristic data of the reshaped soil sample during seepage, the quantitative data of particle redistribution, and the intuitive image comparison results of particle migration.

[0015] Compared with the prior art, the method and system for analyzing the migration of particles in loess under seepage in the present invention have the following beneficial effects: The present invention discloses a method for analyzing particle migration within loess under seepage. This method utilizes nuclear magnetic resonance (NMR) technology, enabling detection without destroying the soil structure. The method integrates multiple particle structure analysis methods, combining the microscopic seepage characteristics obtained by the NMR module, the particle redistribution change characteristics obtained by the particle analysis module, and the particle contact mode and morphological change characteristics obtained by the electron microscope scanning and image processing modules. The method utilizes IPP software to enhance the clarity of particle and pore distinctions in the electron microscope scanning image analysis results, thereby comprehensively exploring the particle migration patterns caused by seepage. The present invention comprehensively considers the microscopic pore particle change characteristics, particle redistribution characteristics, and image comparison, and through microstructural analysis, restores the particle migration process under loess seepage, making the resulting evolution process more accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0017] Figure 1 Schematic diagram of a process for analyzing particle migration in loess under seepage in the present invention; Figure 2 This is a schematic diagram of the architecture of a system for analyzing particle migration inside loess under seepage according to the present invention.

[0018] Figure 3 This is a comparison chart of images obtained by the electron microscope scanning module; Figure 4 This is a comparison chart of images obtained by the particle analysis module; Figure 5 This is the MRI image (macroscopic) obtained by the MRI module; Figure 6 This is the T2 spectrum obtained by the nuclear magnetic resonance module. DETAILED DESCRIPTION

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0022] In the description of the embodiments of the present invention, it should be noted that if the terms "upper," "lower," "horizontal," "inner," etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the inventive product is typically placed when in use. These terms are merely for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," etc. are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0025] How to comprehensively consider the microscopic pore particle change characteristics, particle redistribution characteristics, and image comparison, restore the particle migration process under loess seepage conditions through microstructure analysis, and thus obtain reliable and accurate analysis results of the loess evolution process.

[0026] like Figure 1 and Figure 2 As shown, the present invention provides a method for analyzing the migration of particles inside loess under seepage, comprising the following steps: S1. Pre-treating the soil sample to prepare a reshaped soil sample; S2. Perform electron microscope scanning and particle analysis on the reshaped soil sample to obtain the particle distribution image and particle size distribution data of the reshaped soil sample before seepage; S3. Conduct a seepage test on the reshaped soil sample to monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil sample in real time during the seepage process, and obtain microscopic pore characteristic data of the reshaped soil sample during the seepage process; S4. Perform electron microscope scanning and particle analysis on the reshaped soil sample after seepage to obtain the particle distribution image and particle size distribution data after seepage respectively; S5. Binarize the particle distribution images of the reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; S6. Comparing the particle size distribution data of the reshaped soil sample before and after seepage, quantitatively analyzing the migration pattern of the particle size of the reshaped soil sample, and generating quantitative data of particle redistribution; S7. Combine the macroscopic seepage data and microscopic pore characteristic data of the reshaped soil sample during the seepage process obtained by the nuclear magnetic resonance equipment, the quantitative data of particle redistribution obtained by the electron microscope scanning equipment and the particle analysis equipment, and the intuitive image comparison results of particle migration to comprehensively determine the migration law of the reshaped soil sample particles under the action of seepage.

[0027] The present invention's method for analyzing loess particle migration under seepage conditions involves a comprehensive and systematic study of the behavior of loess particles under seepage, from soil sample pretreatment to seepage testing and subsequent particle analysis before and after seepage. Through the use of electron microscopy, nuclear magnetic resonance (NMR), image processing, and particle analysis, the method comprehensively and systematically investigates the behavior of loess particles under seepage conditions. During the seepage test, the dynamic changes in the water-filled pores and moisture content of the reshaped soil samples were monitored in real time using a NMR module. This data on the microscopic pore characteristics during seepage can be obtained, contributing to a more accurate understanding of the dynamic changes in particle migration during seepage.

[0028] The present invention not only generates intuitive image comparison results of particle migration through the image processing module, but also generates quantitative data of particle redistribution through the particle analysis module. By combining qualitative and quantitative methods, the law of particle migration can be revealed more comprehensively. The present invention can obtain high-resolution particle distribution images and particle size gradation data through electron microscope scanning and particle analysis. Combined with nuclear magnetic resonance technology, it can accurately analyze the changes in microscopic pores during seepage. Combined with the microscopic pore characteristic data, quantitative data of particle redistribution and intuitive image comparison results of macroscopic particle migration, the migration process of particles and structures inside the loess under the action of seepage can be monitored in real time. It can realize dynamic observation of the migration and structural change process of particles inside the loess from a micro-macro multi-scale perspective, and improve the accuracy and reliability of the research on the movement law of loess particle migration.

[0029] In some embodiments, the present invention reshapes soil samples by screening, drying, water spraying, and compacting to ensure uniformity and consistency before seepage testing. The present invention also applies gold spraying to the reshaped soil samples before electron microscopy scanning to improve image quality and reduce charge accumulation on the sample surface, thereby obtaining a clearer image of particle distribution.

[0030] Furthermore, the present invention uses a scanning electron microscope to obtain high-resolution images and a laser particle size analyzer to perform particle size analysis. This ensures the high-precision acquisition of particle distribution images and particle size grading data. In the nuclear magnetic resonance seepage test, the magnetic field intensity and pulse frequency range are controlled, and the soil sample is kept in an undisturbed state, thereby ensuring the stability and consistency of the test conditions and improving the accuracy of the test data. The present invention uses a constant-speed pump to adjust different flow rates, simulates particle migration under different seepage conditions, and records T2 spectra and water-filled pore size distribution curves. This simulation can more realistically reflect the particle migration laws under different seepage conditions, thereby enhancing the applicability of the method.

[0031] Furthermore, the image processing module of the present invention utilizes IPP software for binarization, which enhances the credibility of the intuitive image comparison results of particle migration. Furthermore, by calculating different particle size variations and generating gradation curves, the present invention quantifies the particle migration effect, enabling a more precise description of particle size variation patterns. Combined with a laser particle size analyzer and an electronic balance for particle mass measurement, the method for obtaining quantitative data on particle redistribution is refined, ensuring data accuracy.

[0032] The present invention also provides a system for analyzing the migration of particles inside loess under seepage, the system comprising a nuclear magnetic resonance module, an electron microscope scanning module, an image processing module, and a particle analysis module, wherein: Nuclear Magnetic Resonance Module: Used to conduct seepage tests on reshaped soil samples through the Nuclear Magnetic Resonance (NMR) module, monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil samples in real time during the seepage process, and obtain the microscopic pore characteristic data of the reshaped soil samples during the seepage process; Electron microscope scanning module: used to perform electron microscope scanning and particle analysis on the reshaped soil sample, respectively obtaining the particle distribution image and particle size gradation data of the reshaped soil sample before seepage; The reshaped soil samples after seepage were scanned again with an electron microscope and subjected to particle analysis to obtain particle distribution images and particle size distribution data after seepage respectively. Image processing module: used to perform binary processing on the particle distribution images of reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; Particle analysis module: used to compare the particle size distribution data of the reshaped soil sample before and after seepage through the particle analysis module, quantitatively analyze the migration law of the particle size of the reshaped soil sample, and generate quantitative data of particle redistribution.

[0033] By integrating the above modules, combined with macroscopic seepage data and microscopic pore characteristics of the reshaped soil sample during seepage, quantitative data on particle redistribution, and visual image comparison results of particle migration, the migration patterns of the reshaped soil sample particles under seepage are comprehensively determined from the microscopic to the macroscopic level. The system of the present invention is used to implement a method for analyzing the migration of particles within loess under seepage.

[0034] The following is a further detailed description of a method and system for analyzing particle migration inside loess under seepage in accordance with the present invention through specific embodiments.

[0035] like Figure 1-6As shown, the present invention prepares reshaped soil samples according to the target moisture content and dry density, and tests the reshaped soil samples before the seepage test from different distribution aspects through the electron microscope scanning module and the particle analysis module to obtain image data and quantitative data; the soil sample is subjected to a seepage test through the nuclear magnetic resonance module, and a deep microscopic pore particle structure analysis of the seepage process is performed without damaging the soil sample; the seepage soil sample after the seepage test is tested from different distribution aspects through the electron microscope scanning module and the particle analysis module to obtain image data and quantitative data again; the image analysis module compares and analyzes the particle size of the images before and after the electron microscope scanning to obtain an intuitive particle migration evolution process; the particle analysis module analyzes the samples before and after the nuclear magnetic resonance seepage test to obtain the particle redistribution before and after the seepage to obtain a quantitative data structure; the particle migration is analyzed in combination with the image and quantitative data.

[0036] Specifically, loess samples were first sieved through a 2mm mesh and dried in a 105°C oven. Distilled water was sprayed onto the soil samples until the target moisture content was reached. The samples were then compacted and reshaped into samples with the specified moisture content and dry density. Before seepage, a portion of the prepared soil samples was selected for electron microscopy and particle analysis. For the electron microscopy test, the soil samples were first dried in a 105°C oven. Three pillars, 1 cm long, 1 cm wide, and 2 cm high, were then cut from each side of the dried sample interface. A 1 mm wide groove was carved in the middle to provide a fresh surface for SEM testing. The pillars were then precisely broken along the grooves to expose a fresh surface. Fine particles scattered on the fresh surface were removed using an earwax bulb, and the sample was then placed in an ion sputtering coater for gold coating.

[0037] The gold-plated samples were promptly placed in the sample chamber for analysis. Multiple scans were performed at the center of the sample, with magnifications ranging from 500× to 1000×. For particle analysis, the samples were dried, then screened using an analytical sieve to separate particles of varying sizes. The screened samples were weighed using an electronic balance and analyzed using a laser particle size analyzer. The data from the laser particle size analyzer were collected and analyzed using a computer. A portion of the sample not intended for analysis was placed in the sample chamber of a nuclear magnetic resonance (NMR) instrument, which contains a permanent magnet with a near-constant magnetic field strength and a near-constant temperature. The pulse frequency range was set to 1-30 MHz with an accuracy of 0.1 Hz. After placement in the NMR instrument, the soil sample was preheated by activating the magnetic field. The constant-speed pump was then adjusted to the target flow rate and the test began until the soil sample reached saturation.

[0038] The measured data was inverted and calculated using analytical software to obtain a T2 spectrum. When the soil is fully saturated after seepage, the T2 value of a single pore is proportional to the ratio of the pore's surface area to its volume. Therefore, the water-filled pore size distribution characteristics of the soil sample at each moment can be converted based on the obtained T2 distribution. The water-filled pore size distribution curve obtained by the nuclear magnetic resonance test is smooth across the entire pore size range because placing the soil sample directly into the nuclear magnetic resonance instrument can fully and dynamically capture the soil's seepage process without disturbing the soil sample.

[0039] After the seepage test is completed by the nuclear magnetic resonance module, the soil samples after seepage are processed in the same way as the soil samples before seepage, that is, they are also processed and analyzed by the electron microscope scanning module and the particle analysis module; the images obtained by electron microscope scanning are analyzed by the latest image processing technology (IPP) to obtain the structure and the image results of the pore particle migration change are obtained by the microscopic particle-to-pore ratio, and the particle redistribution results are obtained by the particle analysis results; the nuclear magnetic resonance penetration test is used to observe the water-filled pore volume distribution of the porous sample, the T2 spectrum area, the change characteristics of different types of water-filled pores during infiltration, the particle migration situation, and the different seepage The flow moment nuclear magnetic resonance imaging and other related information and data were used to obtain the pore changes and particle migration under infiltration conditions. The particle migration under different flow rates was obtained by adjusting the constant speed pump. The IPP software was used to enhance the clarity of the electron microscope scanning image analysis results to distinguish between particles and pores. The image was binarized, with pores represented by white and particles by black. The pore percentage at each interface was obtained, thereby obtaining an intuitive law of pore migration changes. The particle size analysis was performed on the soil at the bottom and interface through particle analysis tests to obtain the changes in D30, D60, and D10 to analyze the particle migration.

[0040] The present invention conducts nuclear magnetic resonance (NMR) tests, scanning electron microscopy (SEM) tests, and particle analysis tests on soil samples. Based on the dynamic changes in water-filled pores in the soil during infiltration, advanced digital image processing technology (IPP) is used to analyze the particle size and structural change characteristics of the sample images obtained by scanning electron microscopy before and after seepage. Ultimately, the water-filled pore volume distribution curve, infiltration process imaging, particle morphology, porosity, and inter-particle contact mode at each moment are obtained. Combined with the quantitative data obtained from the particle analysis test, a comprehensive analysis is performed. The present invention combines the microscopic seepage characteristics obtained by the NMR module, the particle redistribution change characteristics obtained by the particle analysis module, and the particle contact mode and morphological change characteristics obtained by the electron microscope scanning module and image processing module to restore the particle migration process under loess seepage conditions from a micro-macro multi-scale perspective, comprehensively exploring the relatively accurate and reliable migration law of loess particles caused by seepage, which has certain reference significance.

[0041] Finally, it should be noted that the above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in this industry can smoothly implement the present invention as shown in the specification and described above. Any equivalent changes, modifications and evolutions made by using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A method for analyzing the migration of particles in loess under seepage, characterized in that: The steps include: S1. Pre-treating the soil sample to prepare a reshaped soil sample; S2. Perform electron microscope scanning and particle analysis on the reshaped soil sample to obtain the particle distribution image and particle size distribution data of the reshaped soil sample before seepage; S3. Conduct a seepage test on the reshaped soil sample to monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil sample in real time during the seepage process, and obtain microscopic pore characteristic data of the reshaped soil sample during the seepage process; S4. Perform electron microscope scanning and particle analysis on the reshaped soil sample after seepage to obtain the particle distribution image and particle size distribution data after seepage respectively; S5. Binarize the particle distribution images of the reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; S6. Comparing the particle size distribution data of the reshaped soil sample before and after seepage, quantitatively analyzing the migration pattern of the particle size of the reshaped soil sample, and generating quantitative data of particle redistribution; S7. Combine the macroscopic seepage data and microscopic pore characteristic data of the reshaped soil sample during the seepage process obtained by the nuclear magnetic resonance equipment, the quantitative data of particle redistribution obtained by the electron microscope scanning equipment and the particle analysis equipment, and the intuitive image comparison results of particle migration to comprehensively determine the migration law of the reshaped soil sample particles under the action of seepage.

2. The method for analyzing the migration of particles in loess under seepage according to claim 1, characterized in that: In said S1, pre-processing the soil sample includes: screening, drying, water spraying and compacting the soil sample according to a preset moisture content and dry density.

3. The method for analyzing the migration of particles in loess under seepage according to claim 1, characterized in that: In the S2, before the electron microscope scanning test, the remolded soil sample is subjected to gold spraying treatment using an ion sputtering coating machine.

4. The method for analyzing the migration of particles in loess under seepage according to claim 3, characterized in that: In S2, a scanning electron microscope is used to perform high-resolution scanning on the soil sample to obtain a microstructure image of the reshaped image before seepage; the microstructure image of the reshaped image is processed to obtain a particle distribution image of the reshaped soil sample before seepage; and a laser particle size analyzer is used to perform particle size analysis on the reshaped soil sample to obtain particle size grading data.

5. The method for analyzing particle migration in loess under seepage according to claim 1, characterized in that: In S3, during the seepage test of the reshaped soil sample using the nuclear magnetic resonance module, the magnetic field intensity of the nuclear magnetic resonance seepage test is controlled to be a constant value, the pulse frequency range is controlled to be 1-30 MHz, and the reshaped soil sample remains in an undisturbed state during the seepage process.

6. The method for analyzing particle migration in loess under seepage according to claim 5, characterized in that: In S3, the nuclear magnetic resonance module adjusts different flow rates through a constant speed pump to simulate the migration of reshaped soil sample particles under different seepage conditions, and records the T2 spectra and water-filled pore size distribution curves under different flow rates.

7. The method for analyzing particle migration in loess under seepage according to claim 1, characterized in that: In the step S5 , the particle distribution images of the reshaped soil sample before and after seepage are binarized using IPP software.

8. The method for analyzing particle migration in loess under seepage according to claim 1, characterized in that: In said S6, quantitatively analyzing the migration law of the particle size of the reshaped soil sample and generating quantitative data of particle redistribution includes: calculating the particle size changes of D10, D30, and D60 of the reshaped soil sample, and generating a gradation curve based on the particle size gradation data to quantify the particle migration effect.

9. The method for analyzing particle migration in loess under seepage according to claim 8, characterized in that: In S6, a laser particle size analyzer is used to analyze the particle size of the remolded soil sample before and after seepage; and an electronic balance is used to weigh the mass of particles of different remolded soil sample sizes to obtain quantitative data on the redistribution of remolded soil sample particles.

10. The system according to any one of claims 1 to 9, wherein the method for analyzing the migration of particles in loess under seepage is based on the system, characterized in that: The system includes a nuclear magnetic resonance module, an electron microscope scanning module, an image processing module and a particle analysis module, wherein: Nuclear Magnetic Resonance Module: Used to conduct seepage tests on reshaped soil samples through the Nuclear Magnetic Resonance (NMR) module, monitor the dynamic changes of the water-filled pores and moisture content of the reshaped soil samples in real time during the seepage process, and obtain macroscopic seepage data and microscopic pore characteristic data of the reshaped soil samples during the seepage process; Electron microscope scanning module: used to perform electron microscope scanning and particle analysis on the reshaped soil sample, respectively obtaining the particle distribution image and particle size gradation data of the reshaped soil sample before seepage; The reshaped soil samples after seepage were scanned again with an electron microscope and subjected to particle analysis to obtain particle distribution images and particle size distribution data after seepage respectively. Image processing module: used to perform binary processing on the particle distribution images of reshaped soil samples before and after seepage, compare the changes in particle morphology, contact mode, and pore distribution, and generate intuitive image comparison results of particle migration; Particle analysis module: used to compare the particle size distribution data of reshaped soil samples before and after seepage through the particle analysis module, quantitatively analyze the migration law of the particle size of the reshaped soil samples, and generate quantitative data of particle redistribution Migration analysis module: It is used to comprehensively determine the migration law of reshaped soil sample particles under seepage by combining the microscopic pore characteristic data of the reshaped soil sample during seepage, the quantitative data of particle redistribution, and the intuitive image comparison results of particle migration.

Images