A soil water characteristic curve acquisition method, system, device and storage medium

Abstract

The application discloses a kind of soil-water characteristic curve acquisition method, system, equipment and storage medium, establish the function relation F (R) of cumulative percentage and particle size R;Determine the component of any particle size Ri belongs to [Ri-△R, Ri+△R];According to the result of S1 and S2, the soil particle quantity corresponding to each component is calculatedAccording to soil particle quantity, the arbitrary pore radius ri corresponding to any particle size Ri is calculated;The cumulative percentage of any pore radius ri less than or equal to a certain pore radius r is calculated, and the volumetric water content of the soil body corresponding to any pore radius ri is calculated according to the cumulative percentage;The matric suction of the soil body is calculated according to any pore radius ri;The relationship between matric suction and saturation is established through any pore radius ri, and the soil-water characteristic curve is obtained.The difference in calculation results caused by the division of random particle groups is eliminated, and the continuous soil-water characteristic curve of different soil bodies, different particle gradation and different compactness can be predicted.

Description

Technical Field

[0001] This invention belongs to the field of soil and water characteristic research, and relates to a method, system, device and storage medium for obtaining soil and water characteristic curves. Background Technology

[0002] In hydrology, the soil-water characteristic curve (SWCC) is one of the most fundamental concepts defining the relationship between soil suction and water content in unsaturated soils, and it is also a basic tool for modeling water, temperature, and solute transport in unsaturated soils. Obtaining a complete SWCC through laboratory experiments is usually very time-consuming and labor-intensive; therefore, establishing a mathematical model of the SWCC from basic unsaturated soil properties is currently the most feasible approach. Existing mathematical models are generally obtained in two ways: empirical models (Van Genuchten and Fredlund & Xing models) and theoretical models (Chen, Mohammadi & Meskini-Vishkaee models). Empirical models are often obtained by fitting many discrete experimental data to form a continuous function. These models, through many fitting parameters, can often fit the experimental data well. However, these empirical models depend on model calibration and the accuracy of experimental data, and many fitting parameters are physically meaningless. Therefore, many scholars have proposed predictive soil-water characteristic curves based on soil material properties, such as mineral content and type, soil density, and pore shape and size. Compared to empirical models, these models can generally reflect the influence of soil properties on soil-water characteristic curves (SWCC) and do not rely on a large amount of experimental time and data. Among them, the Arya and Paris model (hereinafter referred to as the AP model), which considers the effect of particle size distribution (GSD) on the prediction of soil-water characteristic curves, has been widely used. The AP model is a conceptual and mathematical model for predicting soil-water characteristic curves of different soil samples based on particle size distribution and pore conditions. Although the AP model has been adopted by many scholars, several problems have been discovered during its use. For example, the magnitude of the matric suction predicted by the AP model is closely related to the mass of the soil sample; the larger the mass of the soil sample, the larger the predicted value. The results of the AP model are closely related to the particle size distribution, and currently, no reasonable and unified distribution method has been determined. The AP model does not achieve continuous processing of the soil-water characteristic curves, which can lead to biases in the obtained soil-water characteristic curves and result in poor accuracy. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method, system, device and storage medium for obtaining soil-water characteristic curves. This eliminates the differences in calculation results caused by the division of random particle groups and can predict the continuity of soil-water characteristic curves for different soil types, different particle sizes and different compaction degrees.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] A method for obtaining soil-water characteristic curves includes the following steps:

[0006] S1. Establish the functional relationship F(R) between the cumulative percentage and the particle size R;

[0007] S2. Determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs;

[0008] S3. Based on the results of S1 and S2, calculate the number of soil particles n corresponding to each component. i ;

[0009] S4. Based on the number of soil particles n i Calculate the arbitrary pore radius ri corresponding to any particle size Ri;

[0010] S5. Calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r;

[0011] S6. Calculate the matric suction of the soil based on any pore radius ri;

[0012] S7. Calculate the volumetric water content θ of the soil corresponding to any pore radius ri based on the cumulative percentage. vi ;

[0013] S8. Based on matrix suction and volumetric water content θ vi The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves.

[0014] Preferably, 20-30 discretized ΔR ratios are taken and compared with the corresponding arbitrary particle size Ri. The relationship between ΔR / Ri and arbitrary particle size Ri is obtained by nonlinear fitting to obtain the nonlinear equation of Ri-ΔR / Ri. Through the nonlinear equation of Ri-ΔR / Ri, the ΔR corresponding to each average particle size R is calculated to obtain the component [Ri-ΔR, Ri+ΔR] to which the arbitrary particle size Ri belongs.

[0015] Preferably, the number of soil particles n i The calculation formula is:

[0016]

[0017] Where, ρ s m is the particle density. i Let m be the mass of soil component i. i = s ·ω i m s For the mass of the soil, m s =1g, ωi Let i be the mass percentage of component i.

[0018] Preferably, the formula for calculating the arbitrary pore radius ri is:

[0019]

[0020] Where e is the void ratio; ρ s m is the particle density. s For the mass of the soil, m s =1g; α is the shape coefficient of soil particles, α>1.

[0021] Preferably, the matrix suction is calculated using the Young-Laplace equation.

[0022]

[0023] Where σ is the surface tension of water, taken as 72.0 mN / m; The contact angle is given because the water in the soil is pure. r is the pore radius.

[0024] Preferably, assuming that the pores of components with a pore radius less than or equal to ri are filled with water, the volumetric water content θ of the soil with a pore radius less than or equal to ri is... vi It can be represented as:

[0025]

[0026] Where e is the void ratio; ω i Let i be the mass percentage of component i.

[0027] Preferably, based on the matrix suction and volumetric water content θ vi Establish the relationship between particle radius Ri and corresponding matrix suction Ψ i The relationship between R i (Ψ i And by relating this to the soil saturation equation, we can obtain:

[0028]

[0029] Where S is the soil saturation; θ res θ represents the residual water content of the soil. sat denoted as saturated water content of the soil; e is the void ratio.

[0030] A soil-water characteristic curve acquisition system includes:

[0031] The module for establishing functional relationships is used to establish the functional relationship F(R) between the cumulative percentage and the particle size R.

[0032] The component determination module is used to determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs;

[0033] The soil particle quantity calculation module is used to calculate the soil particle quantity n corresponding to each component based on the results of the functional relationship establishment module and the component determination module. i ;

[0034] Arbitrary pore radius calculation module, used to calculate based on the number of soil particles n i Calculate the arbitrary pore radius ri corresponding to any particle size Ri;

[0035] The cumulative percentage calculation module is used to calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r.

[0036] The matrix suction calculation module is used to calculate the matrix suction of soil based on any pore radius ri.

[0037] The volumetric water content calculation module is used to calculate the volumetric water content θ of soil corresponding to any pore radius ri based on a cumulative percentage. vi ;

[0038] The soil-water characteristic curve acquisition module is used to obtain the characteristic curves of the soil based on the matrix suction and volumetric water content θ. vi The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves.

[0039] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for obtaining soil and water characteristic curves.

[0040] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method for obtaining soil and water characteristic curves.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] This invention addresses the problem of existing AP models predicting the matric suction of soil being affected by soil sample mass by defining soil mass as a unit mass (1g), thus ensuring that the calculation results are unaffected by soil mass. By combining 20-30 discretized ratios of ΔR to corresponding particle size Ri proposed by numerous researchers, a nonlinear equation Ri-ΔR / Ri is obtained through nonlinear fitting. This ensures the continuity and determinism of particle size group division, resolving the issue of inconsistent particle size group division affecting the prediction results of existing AP models and eliminating the discrepancies in calculation results caused by random particle size group division. Furthermore, by sorting the pore radii calculated from arbitrary particle sizes and establishing the relationship between pore radius and cumulative percentage, a monotonically continuous soil-water characteristic curve for saturation and matric suction is obtained, solving the problem that the calculated soil-water characteristic curve may not be monotonically continuous due to different slopes of particle size distribution curves. This invention allows for the prediction of continuous soil-water characteristic curves for different soil types, particle sizes, and compaction degrees without requiring extensive laboratory tests of soil matrix suction. It can be achieved solely through the gradation curves and basic physical and mechanical parameters of the tested soil, thus saving a significant amount of experimental work. Attached Figure Description

[0043] Figure 1 This is an AP model flowchart of the method for obtaining soil-water characteristic curves according to the present invention;

[0044] Figure 2 This is a schematic diagram of the nonlinear fitting of △R / Ri-Ri according to the present invention;

[0045] Figure 3 This is a schematic diagram of the particle size distribution curve of the present invention;

[0046] Figure 4 This is a schematic diagram illustrating the functional relationship between the cumulative percentage of the present invention and any particle size Ri;

[0047] Figure 5 This is a schematic diagram of the soil-water characteristic curve of sandy soil predicted by the AP model of the present invention. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0049] It should be noted that the terms “front,” “back,” “left,” “right,” “up,” and “down” used in the following description refer to the directions shown in the attached diagram, while the terms “inside” and “outside” refer to the directions toward or away from the geometric center of a specific component, respectively.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0051] like Figure 1 As shown, this is the method for obtaining soil-water characteristic curves according to the present invention. The AP model first divides the soil particle size distribution (GSD) into n components according to particle size, and sets all components to have the same particle density ρ. s And the void ratio e. Assuming the particle size is spherical, the pores between soil particles in each component are cylindrical. For any particle size Ri of each component in GSD, an arbitrary pore radius ri can be calculated. Based on the calculated arbitrary pore radius ri, the matrix suction Ψ(Ri) of different components can be obtained using the Young-Laplace equation.

[0052] The specific process is as follows:

[0053] 1. Establish the functional relationship F(R) between the cumulative percentage and the particle size R.

[0054] The test soil with the predicted soil-water characteristic curve was subjected to sieve analysis to obtain the gradation curve of the relationship between the cumulative percentage and the particle size R. The functional relationship F(R) between the cumulative percentage and the particle size R was further established.

[0055] 2. Determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs.

[0056] Points are taken at 0.002 mm intervals (0.002 mm, 0.004 mm, 0.006 mm… 0.960 mm…), and each particle size R corresponds to a component [R-ΔR, R+ΔR]. Before solving for the matrix suction Ψ(Ri) corresponding to any particle size Ri, it is necessary to identify the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs from the gradation curve.

[0057] To address the issue of inconsistent ΔR values ​​leading to discrepancies in AP model calculations, this invention combines 20-30 discretized ΔR ratios to corresponding arbitrary particle sizes Ri proposed by numerous researchers, and the relationship between ΔR / Ri and arbitrary particle size Ri. Through nonlinear fitting, a nonlinear equation of Ri-ΔR / Ri is obtained, as shown in [reference needed]. Figure 2 .

[0058] The nonlinear equation Ri-ΔR / Ri can be used to calculate ΔR corresponding to each average particle size R, and thus the composition [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs can be obtained.

[0059] 3. Calculate the number of soil particles n corresponding to each component. i .

[0060] The particle volume V within the range [Ri-△R, Ri+△R] of the i-th component is... si and pore volume V vi It can be represented as:

[0061]

[0062]

[0063] Where, ρ s Particle density (g / cm³) 3 e represents the void ratio (-); m represents the porosity. i Let m be the mass (g) of soil component i. i = s ·ω i m s Let m be the mass of the soil (g). To eliminate the influence of soil mass on the calculation results of matrix suction, m is defined as... s =1g, ω i n is the mass percentage of component i; i The number of soil particles is obtained by reasoning using formula (1):

[0064]

[0065] 4. Calculate the arbitrary pore radius ri corresponding to any particle size Ri.

[0066] Dividing formula (2) by formula (1), the relationship between particle radius Ri and arbitrary pore radius ri is obtained as follows:

[0067]

[0068] Among them, L i L is the length of the cylindrical pore. When the soil particles are assumed to be homogeneous spherical particles, L... i =2Ri n i However, soil particles are usually heterogeneous spherical, and a single soil particle can often provide more than 2 i The pore length, in fact, is L. i >2 i n i Therefore, a shape factor α for soil particles was proposed, where α > 1, such as... Figure 1 As shown.

[0069]

[0070] Substituting formula (5) into formula (4) yields the soil particle size R. i With average aperture r i The correspondence between them yields the formula for calculating the radius ri of any pore:

[0071]

[0072] 5. The cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r.

[0073] The arbitrary pore radii ri corresponding to different components obtained through formula (6) need to be rearranged from smallest to largest. Statistical analysis is performed on particle components with pore radii smaller than a certain pore radius r to obtain the corresponding percentage F. ri≤r (R i ). Among them, F ri≤r (R i Let be the cumulative percentage of any pore radius ri calculated from any particle size Ri that is less than or equal to a certain pore radius r. The above operations eliminate the problem that any particle size Ri and any pore radius ri are not necessarily monotonically positively correlated.

[0074] Since the particle size range is determined by taking samples at 0.002 mm intervals, the radius R of each particle is... i The corresponding mass percentage can be calculated by [F(R)] i +0.001)-(R i +0.001)] is obtained.

[0075] 6. Calculate the matric suction of the soil.

[0076] Calculation of matrix suction using the Young-Laplace equation

[0077]

[0078] Where σ is the surface tension of water, taken as 72.0 mN / m; The contact angle is given because the water in the soil is pure. r is the pore radius.

[0079] 7. Calculate the volumetric water content θ of the soil corresponding to any pore radius ri. vi .

[0080] Assuming that the pores of components with pore radii less than or equal to ri are filled with water, then the volumetric water content (cm³) of the soil with pore radii less than or equal to ri is... 3 / cm 3 )θ vi It can be represented as:

[0081]

[0082] 8. Establish the relationship between matrix suction and saturation.

[0083] Combining formulas (6) and (7), we can establish the relationship between particle radius Ri and the corresponding matrix suction ψ. i The relationship between R i (ψ i And by relating this to the soil saturation equation, we can obtain:

[0084]

[0085] Where S is the soil saturation; θ res θ represents the residual water content of the soil. sat This represents the saturated water content of the soil.

[0086] Based on the relationship between matrix suction and saturation, the soil-water characteristic curve is obtained.

[0087] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. This embodiment predicts the soil-water characteristic curves of typical aeolian sandy soil in roadbeds in Northwest China.

[0088] 1. According to the "Specifications for Geotechnical Testing of Highways" (JTG 3430-2020), if... Figure 3 As shown in Table 1, the basic physical properties of the test soil, such as specific gravity, optimum moisture content, maximum dry density, and particle size distribution, were measured through indoor tests. The shape factor α of the test soil was 1.5.

[0089] Table 1. Basic physical properties of the soil used in the experiment

[0090]

[0091]

[0092] 2. For example Figure 4 As shown, a functional relationship F(Ri) between the cumulative percentage and any particle size Ri is established.

[0093] 3. Take points at 0.002 mm intervals within the particle size range (0.001-1 mm), and calculate the mass percentage ω of the component corresponding to each arbitrary particle size Ri. i =[F(R i +ΔR)-(R i +ΔR)], and then calculate the arbitrary pore radius ri corresponding to each arbitrary particle size Ri according to formula (6) and the basic physical properties of the test soil. Then calculate the corresponding matrix suction Ψ(Ri) according to the Young-Laplace equation (formula 7), as shown in Table 2.

[0094] Table 2. Calculation of matrix suction

[0095]

[0096] 4. As shown in Table 3, due to the difference in particle size distribution slope, the particle size and pore radius are not necessarily monotonically positively correlated. Therefore, smaller particle size does not necessarily mean greater matrix suction calculated by the AP model.

[0097] Table 3. Cases where particle size and pore radius are not monotonically positively correlated.

[0098]

[0099] At this point, the calculated arbitrary pore radii *ri* need to be reordered from smallest to largest. Assuming that the pores of components with pore radii less than or equal to *ri* are filled with water, then the volumetric water content θ of the soil with pore radii less than or equal to *ri* is... vi Calculated using formula (8).

[0100] 5. Establish the correspondence between soil saturation S and matrix suction Ψ using formula (9), such as Figure 5 As shown, the soil-water characteristic curves relating soil saturation S and matrix suction Ψ are plotted.

[0101] The following are embodiments of the apparatus of the present invention, which can be used to execute embodiments of the method of the present invention. For details not omitted in the apparatus embodiments, please refer to the embodiments of the method of the present invention.

[0102] In another embodiment of the present invention, a soil-water characteristic curve acquisition system is provided. This soil-water characteristic curve acquisition system can be used to implement the above-mentioned soil-water characteristic curve acquisition method. Specifically, the soil-water characteristic curve acquisition system includes a function relationship establishment module, a component determination module, a soil particle quantity calculation module, an arbitrary pore radius calculation module, a cumulative percentage calculation module, a matrix suction calculation module, a volumetric water content calculation module, and a soil-water characteristic curve acquisition module.

[0103] The function relationship establishment module is used to establish the functional relationship F(R) between the cumulative percentage and the particle size R.

[0104] The component determination module is used to determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs.

[0105] The soil particle quantity calculation module is used to calculate the soil particle quantity n corresponding to each component based on the results of the functional relationship establishment module and the component determination module. i .

[0106] The arbitrary pore radius calculation module is used to calculate the pore radius based on the number of soil particles n. i Calculate the arbitrary pore radius ri corresponding to any particle size Ri.

[0107] The cumulative percentage calculation module is used to calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r.

[0108] The matrix suction calculation module is used to calculate the matrix suction of soil based on any pore radius ri.

[0109] The volumetric water content calculation module is used to calculate the volumetric water content θ of soil corresponding to any pore radius ri based on the cumulative percentage. vi .

[0110] The soil-water characteristic curve acquisition module is used to obtain the characteristic curves of the soil based on the matrix suction and the volumetric water content θ. vi The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves.

[0111] In another embodiment of the present invention, a terminal device is provided, the terminal device including a processor and a memory, the memory being used to store a computer program, the computer program including program instructions, and the processor being used to execute the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to achieve the corresponding method flow or corresponding function. The processor described in this embodiment can be used in the operation of the soil-water characteristic curve acquisition method, including: S1, establishing a functional relationship F(R) between the cumulative percentage and the particle size R; S2, determining the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs; S3, calculating the number of soil particles n corresponding to each component based on the results of S1 and S2. i S4. Based on the number of soil particles n i S5. Calculate the arbitrary pore radius ri corresponding to any particle size Ri; S6. Calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r; S7. Calculate the matric suction of the soil based on any pore radius ri; S8. Calculate the volumetric water content θ of the soil corresponding to any pore radius ri based on the cumulative percentage. vi S8. Based on the matrix suction and volumetric water content θ vi The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves.

[0112] In another embodiment, the present invention also provides a computer-readable storage medium (Memory), which is a memory device in a terminal device for storing programs and data. It is understood that the computer-readable storage medium here may include both the built-in storage medium in the terminal device and extended storage media supported by the terminal device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor, which may be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here may be high-speed RAM or non-volatile memory, such as at least one disk storage device.

[0113] One or more instructions stored in the computer-readable storage medium can be loaded and executed by the processor to implement the corresponding steps of the soil-water characteristic curve acquisition method in the above embodiments; one or more instructions in the computer-readable storage medium are loaded and executed by the processor in the following steps: S1, establish the functional relationship F(R) between the cumulative percentage and the particle size R; S2, determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs; S3, calculate the number of soil particles n corresponding to each component based on the results of S1 and S2. i S4. Based on the number of soil particles n i S5. Calculate the arbitrary pore radius ri corresponding to any particle size Ri; S6. Calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r; S7. Calculate the matric suction of the soil based on any pore radius ri; S8. Calculate the volumetric water content θ of the soil corresponding to any pore radius ri based on the cumulative percentage. vi S8. Based on the matrix suction and volumetric water content θ vi The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves.

[0114] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0115] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0116] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0117] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0118] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0119] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A method for obtaining soil-water characteristic curves, characterized in that, Includes the following processes: S1. Establish the functional relationship F(R) between the cumulative percentage and the particle size R; S2. Determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs; Take 20-30 discretized ΔR ratios and corresponding arbitrary particle sizes Ri. The relationship between ΔR / Ri and arbitrary particle sizes Ri is obtained by nonlinear fitting to obtain the nonlinear equation of Ri-ΔR / Ri. Through the nonlinear equation of Ri-ΔR / Ri, the ΔR corresponding to each average particle size R is calculated to obtain the component [Ri-ΔR, Ri+ΔR] to which the arbitrary particle size Ri belongs. S3. Based on the results of S1 and S2, calculate the number of soil particles corresponding to each component. ; S4. Based on the number of soil particles Calculate the arbitrary pore radius ri corresponding to any particle size Ri; The formula for calculating the radius ri of any pore is: ； in, Porosity; Particle density; For the quality of the soil, ; This represents the shape factor of the soil particles. ; S5. Calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r; S6. Calculate the matric suction of the soil based on any pore radius ri; S7. Calculate the volumetric water content of the soil corresponding to any pore radius ri based on the cumulative percentage. ; Assuming that the pores of components with a pore radius less than or equal to ri are filled with water, then the volumetric water content of the soil with a pore radius less than or equal to ri is... It can be represented as: ； in, Porosity; This represents the mass percentage of component i. S8. Based on matrix suction and volumetric moisture content The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves; Based on matrix suction and volumetric water content Establish the relationship between particle radius Ri and corresponding matrix suction. Relationship And by establishing a connection with the soil saturation equation, we can obtain: ； in, Soil saturation; This refers to the residual water content of the soil. The saturated water content of the soil; It represents the void ratio.

2. The method for obtaining soil-water characteristic curves according to claim 1, characterized in that, Number of soil particles The calculation formula is: ； in, Particle density; Let i be the mass of the soil component. , For the quality of the soil, , Let i be the mass percentage of component i.

3. The method for obtaining soil-water characteristic curves according to claim 1, characterized in that, Calculation of matrix suction using the Young-Laplace equation ； in, The surface tension of water is taken as 72.0 mN / m; The contact angle is given because the water in the soil is pure. ; Where is the pore radius.

4. A system for obtaining soil-water characteristic curves, characterized in that, include: The module for establishing functional relationships is used to establish the functional relationship F(R) between the cumulative percentage and the particle size R. The component determination module is used to determine the component [Ri-ΔR, Ri+ΔR] to which any particle size Ri belongs; Take 20-30 discretized ΔR ratios and corresponding arbitrary particle sizes Ri. The relationship between ΔR / Ri and arbitrary particle sizes Ri is obtained by nonlinear fitting to obtain the nonlinear equation of Ri-ΔR / Ri. Through the nonlinear equation of Ri-ΔR / Ri, the ΔR corresponding to each average particle size R is calculated to obtain the component [Ri-ΔR, Ri+ΔR] to which the arbitrary particle size Ri belongs. The soil particle quantity calculation module is used to calculate the soil particle quantity corresponding to each component based on the results of the function relationship establishment module and the component determination module. ; Arbitrary pore radius calculation module, used to calculate based on the number of soil particles Calculate the arbitrary pore radius ri corresponding to any particle size Ri; The formula for calculating the radius ri of any pore is: ； in, Porosity; Particle density; For the quality of the soil, ; This represents the shape factor of the soil particles. ; The cumulative percentage calculation module is used to calculate the cumulative percentage of any pore radius ri that is less than or equal to a certain pore radius r. The matrix suction calculation module is used to calculate the matrix suction of soil based on any pore radius ri. The volumetric water content calculation module is used to calculate the volumetric water content of soil corresponding to any pore radius ri based on a cumulative percentage. ; Assuming that the pores of components with a pore radius less than or equal to ri are filled with water, then the volumetric water content of the soil with a pore radius less than or equal to ri is... It can be represented as: ； in, Porosity; This represents the mass percentage of component i. The soil-water characteristic curve acquisition module is used to obtain the characteristic curves of the soil based on the matrix suction and volumetric water content. The relationship between matrix suction and saturation was established to obtain soil-water characteristic curves; Based on matrix suction and volumetric water content Establish the relationship between particle radius Ri and corresponding matrix suction. Relationship And by establishing a connection with the soil saturation equation, we can obtain: ； in, Soil saturation; This refers to the residual water content of the soil. The saturated water content of the soil; It represents the void ratio.

5. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method for obtaining soil and water characteristic curves as described in any one of claims 1 to 3.

6. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for obtaining soil and water characteristic curves as described in any one of claims 1 to 3.

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