Method and device for acquiring application range of anchoring effect of plant root system

Abstract

The invention discloses a method and device for obtaining the application range of the anchoring effect of a plant root system. The method for acquiring the application range of the anchoring effect of the plant root system comprises the following steps: acquiring parameter information of a to-be-detected plant; obtaining a plant root system anchoring effect index model; inputting the parameter information of the plant to be detected into the plant root system anchoring effect index model so as to obtain a plant root system anchoring effect index; obtaining an index suggestion comparison table, wherein the index suggestion comparison table comprises at least one preset numerical value interval and an applicable suggestion corresponding to each preset numerical value interval; and obtaining an applicable suggestion corresponding to the preset numerical value interval in which the anchoring effect index of the plant root system is located. According to the method for obtaining the application range of the anchoring effect of the plant root system, multiple root system parameters are normalized and integrated into a comparable index, the comparable index is used for evaluating the anchoring capacity of the plant root system, and engineering plant selection and slope stability design are facilitated.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of soil and water loss prevention, and in particular to a method for obtaining the applicable range of plant root anchoring effect and a device for obtaining the applicable range of plant root anchoring effect. BACKGROUND

[0002] At present, in slope reinforcement and soil and water conservation engineering, means such as anchor rods, sprayed concrete and geogrids are often used, which can effectively enhance the stability of the slope, but are often accompanied by high energy consumption, high cost and great disturbance to the ecological environment. The plant soil fixation method gradually attracts attention due to its low carbon and environmental protection and low cost. However, the traditional plant soil fixation method mainly relies on the natural growth of plant roots, lacks scientific evaluation and construction guidance, and has unstable anchoring effect, long cycle and weak anti-scouring ability, which limits its engineering application.

[0003] The "plant root anchoring effect" refers to the interaction between plant roots and soil through physical, chemical and biological mechanisms, which enhances the stability of the slope soil, improves the anti-scouring and anti-sliding abilities, and thus plays a role in "anchoring" the surface and shallow soil similar to an anchor rod to a certain extent. This effect has important significance in the fields of ecological restoration, slope stability, vegetation slope protection and soil and water conservation.

[0004] At present, the understanding of the plant anchoring mechanism in engineering practice is still rough, mainly relying on the natural growth of plant roots and empirical layout, lacking systematic mechanical modeling and construction parameter guidance, resulting in problems such as large fluctuation of anchoring effect, long action cycle and insufficient anti-disturbance ability, which seriously limits the engineering popularization and application efficiency of the plant anchoring effect. Therefore, it is urgent to build an improved model of plant root anchoring effect based on mechanical principles, which can accurately represent the process of plant root-soil interaction, improve the engineering controllability and adaptability of plant soil fixation technology, and provide a scientific basis for slope ecological reinforcement design and construction.

[0005] The main mechanism and performance of the root anchoring effect: root penetration and winding effect, the plant roots penetrate the soil to form "natural anchor rods", generate friction force through the root-soil contact interface, and enhance the integrity and shear strength of the soil structure. Root reinforcement effect, similar to the principle of reinforced soil in engineering, plant roots as "natural reinforcement material" form a complex network structure in the soil, improve the soil tensile and shear resistance, inhibit crack propagation and sliding, thereby increasing the surface soil erosion resistance, reducing the surface runoff erosion and fine soil loss caused by rainfall, and reducing the erosion risk.

[0006] Plant root exudates can promote the formation of granular structure, for example, polysaccharides, organic acids and the like help fine soil particles to be cemented into more stable soil granular structure, and enhance the soil structure stability and aeration and drainage capacity. At the same time, root microorganisms (such as nitrogen-fixing bacteria and mycorrhizal fungi) further improve the root anchoring capacity and soil anti-disturbance performance by promoting nutrient cycling, soil particle cementation, regulating root growth and the like.

[0007] The influence of root characteristics on anchoring effect is as follows: Root characteristics Effect on anchoring Root density The higher the density, the stronger the anchoring capacity; enhances the reinforcement and retention of surface soil Root distribution depth Deep-rooted plants have stronger anchoring capacity in deep soil, suitable for steeper slopes Root morphology Fibrous roots are beneficial to surface soil fixation, while taproots are beneficial to penetrating deep structures Root growth direction and angle Roots that tend to be horizontally distributed are more beneficial to shear strength enhancement, while vertical distribution enhances slip resistance The existing "anchoring effect calculation model" cannot comprehensively reflect the influence of root characteristics on anchoring effect. SUMMARY

[0008] The present application aims to provide a plant root anchoring effect applicable range acquisition method to at least solve one of the above technical problems.

[0009] In one aspect of the present application, a plant root anchoring effect applicable range acquisition method is provided, which comprises: acquiring plant parameter information to be detected; acquiring a plant root anchoring effect index model; inputting the plant parameter information to be detected into the plant root anchoring effect index model, thereby acquiring a plant root anchoring effect index; acquiring an index suggestion table, the index suggestion table comprising at least one preset numerical interval and an applicable suggestion corresponding to each preset numerical interval; acquiring the applicable suggestion corresponding to the preset numerical interval in which the plant root anchoring effect index is located.

[0010] Optionally, the plant root anchoring effect index model is as follows: ; wherein RREI is a plant root anchoring effect index; is a normalized root density; is a normalized average root length; is a normalized root distribution angle factor; is a normalized root elastic modulus; is a normalized maximum tensile strength of root; is a weight coefficient, wherein i=1, 2, 3, 4, 5, and W1+W2+W3+W4+W5=1.

[0011] Optionally, before the plant root anchoring effect index model is acquired, the plant root anchoring effect applicable range acquisition method further comprises: acquiring basic parameters of the land to be transplanted; acquiring equivalent shear strength of root-soil composite according to the basic parameters of the land to be transplanted; acquiring equivalent shear strength of root-soil composite and root length density according to the equivalent shear strength of root-soil composite; acquiring slope safety factor according to the equivalent shear strength of root-soil composite, the equivalent shear strength of root-soil composite and the root length density; acquiring adaptive weight coefficient set according to the slope safety factor and plant parameter information to be detected; the plant root anchoring effect index model, thereby acquiring the plant root anchoring effect index. the plant root anchoring effect index model, thereby acquiring the plant root anchoring effect index.

[0012] Optionally, the plant root anchoring effect index model is as follows: ; wherein RREI is the plant root anchoring effect index; is the normalized plant parameter information to be detected; is the slope safety factor; is the minimum value of the slope safety factor; is the maximum value of the slope safety factor; is the weight coefficient.

[0013] Optionally, the basic parameters of the land to be transplanted include internal friction angle, cohesion, slope geometric parameters and water characteristic curve. the basic parameters of the land to be transplanted includes internal friction angle, cohesion, slope geometric parameters and water characteristic curve. acquiring root-soil interface crack propagation parameters and critical crack length according to the basic parameters of the land to be transplanted and the plant parameter information to be detected; generating root-soil interface equivalent shear strength according to the root-soil interface crack propagation parameters and the water characteristic curve.

[0014] Optionally, the acquiring equivalent shear strength of root-soil composite and root length density according to the equivalent shear strength of root-soil composite includes: establishing a root-soil composite two-dimensional model using FLAC3D, defining a root distribution area, and assigning root parameters and soil parameters; performing mechanical response simulation on the root-soil composite two-dimensional model, thereby acquiring the equivalent shear strength of root-soil composite and the root length density.

[0015] Optionally, the obtaining the slope safety factor according to the equivalent shear strength of the root-soil composite, the equivalent shear strength of the root-soil composite, and the root length density comprises: constructing a dynamic root-soil composite constitutive model; obtaining a corrected internal friction angle according to the internal friction angle; obtaining a corrected cohesion according to the cohesion; obtaining a slope safety factor according to the dynamic root-soil composite constitutive model, the corrected internal friction angle, the corrected cohesion, and slope geometric parameters.

[0016] Optionally, the obtaining the slope safety factor according to the dynamic root-soil composite constitutive model, the corrected internal friction angle, the corrected cohesion, and slope geometric parameters comprises: constructing a meso-scale finite element model, the meso-scale finite element model comprising: generating a slope surface according to a slope angle, a height, and a platform width by a geometric projection method; generating randomly distributed beam elements in the soil according to a root distribution depth, the direction of the beam elements subjecting to a statistical distribution of a branching angle β; constructing a root constitutive relationship and a soil constitutive relationship; performing grid division, the grid division principles comprising: using a structured hexahedral grid in a root region; using an unstructured tetrahedral grid in a non-root region, the element size gradually increasing from the root boundary outward; displacement constraints comprising: fixing the bottom and applying rolling support to the lateral boundary; load application comprising: applying a gravity load to the top and loading step by step in 10 load steps; iteratively calculating by a finite element solver (such as an explicit algorithm of FLAC3D or an implicit algorithm of ABAQUS) and outputting a soil strain distribution cloud map and stress field data; based on the soil strain distribution cloud map output by the meso-scale finite element model, using a strain energy density criterion to define a region with a strain of >0.5% as a high strain region; equally spacing sampling the high strain region along the slope direction, each sampling point corresponding to an initial sliding surface, the sliding surface being a circular arc, thereby obtaining an initial sliding surface set; optimizing the initial sliding surface set by a genetic algorithm, thereby obtaining optimal sliding surface control point coordinates and a minimum safety factor, the minimum safety factor being the slope safety factor.

[0017] Optionally, when optimizing the initial sliding surface set by the genetic algorithm, the fitness function used is as follows: ; wherein, , wherein, is the slope safety factor; is the corrected soil cohesion; b is the strip width; is the shear strength of the root-soil composite; is the tangent value of the corrected internal friction angle of soil; is the soil density; g is the acceleration of gravity; and z is the strip depth; is the sine value of the strip inclination angle.

[0018] The application further provides a plant root anchoring effect applicable range obtaining device, which comprises: a to-be-detected plant parameter information obtaining module, which is configured to obtain to-be-detected plant parameter information; a model obtaining module, which is configured to obtain a plant root anchoring effect index model; an effect index calculating module, which is configured to input the to-be-detected plant parameter information into the plant root anchoring effect index model, so as to obtain a plant root anchoring effect index; a reference table obtaining module, which is configured to obtain an index suggestion reference table, the index suggestion reference table comprising at least one preset numerical interval and an applicable suggestion corresponding to each preset numerical interval; an applicable suggestion obtaining module, which is configured to obtain the applicable suggestion corresponding to the preset numerical interval in which the plant root anchoring effect index is located.

[0019] Beneficial effects:

[0020] The plant root anchoring effect applicable range obtaining method provided by the application integrates multiple root system parameters into one comparable index, which is used to evaluate the strength of the plant root anchoring capacity, and is convenient for engineering plant selection and slope stability design. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a flowchart of the plant root anchoring effect applicable range obtaining method according to an embodiment of the application; Figure 2 is a schematic diagram of measuring root system mechanical parameters by using an electronic universal testing machine. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0023] Example 1:

[0024] like Figure 1 The methods for determining the applicable scope of the plant root anchoring effect shown include: Step 1: Obtain the parameter information of the plant to be tested; Step 2: Obtain the plant root anchoring effect index model; Step 3: Input the plant parameter information to be detected into the plant root anchoring effect index model to obtain the plant root anchoring effect index; Step 4: Obtain the index suggestion reference table, which includes at least one preset value range and the applicable suggestions corresponding to each preset value range; Step 5: Obtain applicable recommendations corresponding to the preset numerical range in which the plant root anchoring effect index is located.

[0025] This paper presents a Root Reinforcement Effect Index (RREI) model. This model normalizes and integrates multiple root parameters into a comparable index to assess the strength of plant root anchoring capacity, facilitating engineering planting and slope stability design.

[0026] The plant root anchoring effect index model is a multi-factor evaluation model that takes root structure characteristic parameters as input and outputs an anchoring effect strength index. The model features: strong engineering applicability; parameters can be measured or assigned values ​​from literature; and it can be used to evaluate the suitability of different plant species and slope types.

[0027] This paper defines the anchoring effect strength index (RREI) as: , The parameters are defined as follows:

[0028] In order to realize the integration of different dimension indexes, each parameter is normalized by using the minimum-maximum normalization method: , The final model is expressed as: ; Wherein: W1+W2+W3+W4+W5=1; Root distribution angle factor calculation: ; Wherein: : average angle between root and slope normal When approaching 90° (perpendicular to the slope), the anchoring effect is best.

[0029] In this embodiment, the index recommendation table is as shown in Table 2: Table 2:

[0030] The present application is further described in detail by way of example, and it can be understood that the example does not constitute any limitation on the present application.

[0031] For the purpose of calculation process description, it is assumed that the measured results of each parameter of a certain plant are as follows: =0.35g / cm3, the minimum value is 0.20, the maximum value is 0.45, and the weight coefficient is 0.25; =35cm, the minimum value is 0.20, the maximum value is 0.40, and the weight coefficient is 0.20; =70°, and the weight coefficient is 0.20; Er=200Mpa, the minimum value is 200, the maximum value is 300, and the weight coefficient is 0.15; Tr=180N, the minimum value is 100, the maximum value is 2300, and the weight coefficient is 0.20; After normalization, the formula is calculated as: , ; The calculation results are shown in Table 3: Table 3:

[0032] The final RREI=0.53 → the anchoring effect is "strong", and the application suggestion is obtained: it can be planted as the main species of ecological slope protection for medium and gentle slopes.

[0033] The root system physical parameters (such as Table 4) are measured by using a root system scanning instrument with giant reed as the test plant.

[0034] Table 4:

[0035] Referring to Figure 2 The root system mechanical parameters are measured by using an electronic universal testing machine. The bottom stem of the mature giant reed is subjected to the tensile test along the grain by using the electronic universal material testing machine. The average moisture content of the bottom stem of the giant reed is 75%, the average value of the tensile elastic modulus of the bottom stem of the giant reed is 587.74 MPa, the minimum value is 513.18 MPa, and the maximum value is 690.25 MPa; the average value of the maximum tensile strength is 91.12 N, the minimum value is 74.31 N, and the maximum value is 103.28 N.

[0036] The plant root anchoring effect index model is substituted to obtain Table 5: Table 5:

[0037] The final RREI is 0.45, the anchoring effect is “strong”, and the applicable suggestion is obtained: the giant reed can be planted as the main species of the ecological slope protection.

[0038] Embodiment 2:

[0039] On the basis of the above method, the present application is improved as follows: Before the plant root anchoring effect index model is obtained, the plant root anchoring effect applicable range acquisition method further includes: Basic parameters of the land to be transplanted are acquired; in the embodiment, the basic parameters of the land to be transplanted can include root system morphological parameters, root system mechanical parameters, and the basic parameters of the land to be transplanted include an internal friction angle, a cohesion, a slope geometric parameter, and a water characteristic curve, wherein the root system morphological parameters include a root diameter distribution (RD), a branch angle (β), and a root length density (RLD); the root system mechanical parameters include an elastic modulus (Er), a tensile strength (Tr), and a fracture strain (εf).

[0040] The equivalent shear strength of the root-soil composite is acquired according to the basic parameters of the land to be transplanted. In the embodiment, the equivalent shear strength of the root-soil composite is acquired according to the basic parameters of the land to be transplanted, which includes: The root-soil interface crack propagation parameters and the critical crack length are acquired according to the basic parameters of the land to be transplanted and the plant parameter information to be detected. The root-soil interface equivalent shear strength is generated according to the root-soil interface crack propagation parameters and the water characteristic curve.

[0041] Specifically, according to the basic parameters of the land to be transplanted and the plant parameter information to be detected, the root-soil interface crack propagation parameters and the critical crack length are obtained, including: Based on the Griffith theory, a root-soil interface crack propagation model is established, RD, β, Er, Tr are input, the stress intensity factor (K) and the energy release rate (G) are calculated, when G≥2γs (γs is the surface energy), the crack starts to expand, the crack propagation path is adjusted combined with the soil water characteristic curve, so as to obtain the root-soil interface crack propagation parameters and the critical crack length.

[0042] Specifically, the stress intensity factor is calculated by the following formula: ; Wherein a is the crack length, RD is the root diameter, β is the angle between the root and the slope surface. Tr is the tensile strength of the root (MPa); Specifically, the energy release rate is calculated by the following formula: ; Wherein Er is the elastic modulus of the root.

[0043] When , the crack starts to expand unstably, wherein is the surface energy of the soil. Substitute the expression of G into the critical condition: , and solve a by algebraic transformation: ; In this embodiment, a is a variable, and the critical condition is a specific value when , so the solved a is this specific value, that is, the critical crack length .

[0044] A model is established based on the actual size of the root-soil interface by the finite element method, wherein the establishment conditions are as follows: The boundary conditions include normal stress, tangential stress and water circulation.

[0045] Crack propagation simulation: Path adjustment: Wetting stage: the soil suction decreases, and the crack tends to expand along the root direction (θ≈β).

[0046] Dry stage: the soil suction (ψ) increases, and the crack propagation direction deviates from the root (θ>β).

[0047] Rate calculation: ; Wherein C and m are material constants (calibrated by cyclic loading test), is the stress intensity factor amplitude.

[0048] The crack propagation direction (θ) and rate (da / dN) are obtained by finite element calculation.

[0049] In this embodiment, the equivalent shear strength of the root-soil composite is calculated by the following formula: , wherein, is the equivalent shear strength of the root-soil composite; reflects the weakening of the crack propagation direction on the root reinforcement effect (the greater θ, the more significant the weakening); reflects the attenuation of the crack length on the root reinforcement effect (the greater a, the more significant the attenuation); c is the soil cohesion; is the normal stress; is the internal friction angle of the soil; RTD is the root tensile density; is the root tensile strength; RD is the root diameter; is the crack length; is the critical crack length; is the included angle between the crack propagation direction and the root.

[0050] In this embodiment, the mesoscopic root-soil composite equivalent shear strength and root length density are obtained according to the equivalent shear strength of the root-soil composite, including: A two-dimensional model of the root-soil composite is established using FLAC3D, the root distribution area is defined, and the root parameters and soil parameters are assigned; The mechanical response simulation of the two-dimensional model of the root-soil composite is performed (gravity load is applied, and the stress-strain relationship of the root-soil composite under the action of the load is calculated), so as to obtain the equivalent shear strength of the root-soil composite and the root length density.

[0051] The slope safety factor is obtained according to the microcosmic root-soil composite equivalent shear strength, the mesoscopic root-soil composite equivalent shear strength, and the root length density, including: A dynamic root-soil composite constitutive model is constructed; A corrected internal friction angle is obtained according to the internal friction angle; A corrected cohesion is obtained according to the cohesion; The slope safety factor is obtained according to the dynamic root-soil composite constitutive model, the corrected internal friction angle, the corrected cohesion, and the slope geometric parameters.

[0052] Specifically, the dynamic constitutive model is constructed as follows: A nonlinear relationship between the strength of the root-soil composite and the strain (ε) is defined: ; wherein: k is the attenuation coefficient (determined by microcosmic fracture test), Strain of soil (extracted from meso-scale finite element model).

[0053] Introducing the spatial distribution function of RLD: where z is the depth, is the root distribution depth, is the average root length density.

[0054] Adjusting the internal friction angle and cohesion of soil according to RLD(z): , ; The method for obtaining the safety factor of the slope according to the dynamic root-soil composite constitutive model, the adjusted internal friction angle, the adjusted cohesion, and the geometric parameters of the slope comprises the following steps: Constructing a meso-scale finite element model, the meso-scale finite element model comprising: generating a slope surface by a geometric projection method according to a slope angle, a height, and a platform width; generating randomly distributed beam elements in the soil according to a root distribution depth, the direction of the beam elements subjecting to a statistical distribution of a branching angle; constructing a root constitutive relationship and a soil constitutive relationship; performing mesh division, the mesh division principles comprising: using a structured hexahedral mesh in a root region; using an unstructured tetrahedral mesh in a non-root region, and gradually increasing the element size from the root boundary outward; displacement constraints comprising: fixing the bottom and applying rolling support to the lateral boundary; load application comprising: applying a gravity load to the top and loading step by step in 10 load steps; iteratively calculating by a finite element solver (such as an explicit algorithm of FLAC3D or an implicit algorithm of ABAQUS), and outputting a soil strain distribution cloud and stress field data; Based on the soil strain distribution cloud output by the meso-scale finite element model, using a strain energy density criterion, defining the region with a strain of greater than 0.5% as a high strain region; Equidistantly sampling the high strain region along the slope direction, each sampling point corresponding to an initial sliding surface, the sliding surface being a circular arc, and the radius R being determined by the principle of minimum potential energy, thereby obtaining an initial sliding surface set (containing 10-20 candidate sliding surfaces, each sliding surface being generated from a high strain region sampling point); Optimizing the initial sliding surface set by a genetic algorithm, thereby obtaining optimal sliding surface control point coordinates and a minimum safety factor, the minimum safety factor being used as the safety factor of the slope.

[0055] Specifically, the core of the genetic algorithm optimization is to find the most dangerous sliding surface corresponding to the minimum safety factor (Fs) through iterative search. The specific steps are as follows: Chromosome coding and decoding: converting the sliding surface parameters into a gene form operable by the genetic algorithm, and ensuring that the decoded sliding surface has physical meaning.

[0056] Encoding: Operation object: each sliding surface in the initial sliding surface set.

[0057] Method: map the sliding surface control point coordinates (x, y) into a binary string.

[0058] Each coordinate is represented by 16 bits of binary (precision 0.1 m).

[0059] Total chromosome length L = 2 x N x 16, N being the number of control points.

[0060] For example, the control point coordinates (x = 2.5 m, y = 1.8 m) converted to binary can be as follows: x: 00000010100101 (corresponding to decimal 2.5), y: 00000001111010 (corresponding to decimal 1.8).

[0061] Decoding: Operation object: binary string.

[0062] Method: group the binary string by 16 bits and convert to decimal coordinates.

[0063] The number of control points can be dynamically adjusted based on the height of the slope.

[0064] In this embodiment, when optimizing the initial sliding surface set by the genetic algorithm, the fitness function used is as follows: ; wherein, , wherein, is the safety factor of the slope; is the corrected soil cohesion; b is the width of the strip; is the shear strength of the root soil complex; is the tangent of the corrected soil internal friction angle; is the soil density; g is the acceleration of gravity; z is the depth of the strip; is the sine of the strip inclination.

[0065] In this embodiment, the fitness f is inversely proportional to the safety factor , i.e. , The genetic algorithm aims to minimize the Therefore, the greater the fitness, the more dangerous the sliding surface.

[0066] In this embodiment, the termination condition is as follows: The iteration number reaches 100 generations, or the fitness function value (f) does not change significantly (change amount <1%) for 10 generations in succession.

[0067] In the present embodiment, the Sobol index method can be used to quantify the contribution of each parameter to the RREI, so as to automatically adjust the weight coefficient (Wi) and ensure that the parameter with a higher contribution obtains a larger weight.

[0068] The plant parameter information to be detected is input into the plant root anchoring effect index model, so as to obtain the plant root anchoring effect index. The adaptive weight coefficient set and the plant parameter information to be detected are input into the plant root anchoring effect index model, so as to obtain the plant root anchoring effect index.

[0069] In the present embodiment, the plant root anchoring effect index model is as follows: ; wherein RREI is the plant root anchoring effect index; is the normalized plant parameter information to be detected; is the slope safety factor; is the minimum value of the slope safety factor; is the maximum value of the slope safety factor; is the weight coefficient.

[0070] It can be understood that the adaptive weight coefficient set and the plant parameter information to be detected are input into the plant root anchoring effect index model, so as to obtain the plant root anchoring effect index, which is the same as that in Embodiment 1, and only the formula used is different, which will not be described herein.

[0071] The present application processes and obtains the slope safety factor from the micro and meso aspects, so that the slope safety factor obtained is more accurate. The synergy verification of the micro mechanism (crack propagation) and the meso behavior (composite mechanics) avoids the limitations of a single scale model; the micro analytical solution ensures the mathematical rigor of the critical condition, and the meso finite element method improves the authenticity of the macro response, and the combination of the two makes the prediction deviation of the RREI significantly reduced.

[0072] Through the theory of fracture mechanics, an analytical model of root-soil interface crack propagation is established to calculate the stress intensity factor and energy release rate; combined with the soil surface energy, an explicit formula of the critical crack length is derived to determine the physical threshold of root anchoring failure (such as crack unstable propagation when ), avoiding the subjectivity of empirical formula; the crack propagation path and rate are adjusted through the soil water characteristic curve (SWCC) to quantify the dynamic influence of dry-wet cycle on anchoring effect.

[0073] ​​Using FLAC3D to establish a two-dimensional model of root-soil composite, giving root parameters and soil parameters; applying gravity load, simulating stress-strain relationship, directly outputting equivalent shear strength and root length density.

[0074] By finite element method to capture the nonlinear mechanical behavior of root-soil composite (such as stress redistribution, plastic zone development), ensure that the meso root-soil composite equivalent shear strength reflects the real response of actual engineering scale The application also provides a plant root anchoring effect applicable range obtaining device, the plant root anchoring effect applicable range obtaining device includes to be detected plant parameter information acquisition module, model acquisition module, effect index calculation module, contrast table acquisition module and applicable suggestion acquisition module, wherein, The to-be-detected plant parameter information acquisition module is used for acquiring to-be-detected plant parameter information; The model acquisition module is used for acquiring a plant root anchoring effect index model; The effect index calculation module is used for inputting the to-be-detected plant parameter information into the plant root anchoring effect index model, so as to obtain a plant root anchoring effect index; The contrast table acquisition module is used for acquiring an index suggestion contrast table, and the index suggestion contrast table includes at least one preset numerical interval and applicable suggestions corresponding to each preset numerical interval; The applicable suggestion acquisition module is used for acquiring applicable suggestions corresponding to a preset numerical interval in which the plant root anchoring effect index is located.

[0075] Although the present application has been described in detail above with general description and specific embodiments, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application, all belong to the scope of the present application.

Claims

1. A method for obtaining a range of applicability of a plant root anchoring effect, characterized in that, The plant root anchoring effect application range acquisition method comprises: acquiring plant parameter information to be detected; acquiring a plant root anchoring effect index model; inputting the plant parameter information to be detected into the plant root anchoring effect index model, thereby acquiring a plant root anchoring effect index; acquiring an index suggestion table, the index suggestion table comprising at least one preset numerical interval and an application suggestion corresponding to each preset numerical interval; acquiring an application suggestion corresponding to a preset numerical interval in which the plant root anchoring effect index is located.

2. The plant root anchoring effect applicability acquisition method according to claim 1, wherein The plant root anchoring effect index model is as follows: ； wherein RREI is a plant root anchoring effect index; is a normalized root density; is a normalized average root length; is a normalized root distribution angle factor; is a normalized root elasticity modulus; is a normalized maximum root tensile strength; is a weight coefficient, wherein i = 1, 2, 3, 4, 5, and W1+W2+W3+W4+W5=1.

3. The plant root anchoring effect applicability acquisition method according to claim 1, wherein Before the plant root anchoring effect index model is acquired, the plant root anchoring effect application range acquisition method further comprises: acquiring basic parameters of land to be transplanted; acquiring micro root-soil composite equivalent shear strength according to the basic parameters of the land to be transplanted; acquiring meso root-soil composite equivalent shear strength and root length density according to the basic parameters of the land to be transplanted; acquiring a slope safety factor according to the micro root-soil composite equivalent shear strength, the meso root-soil composite equivalent shear strength and the root length density; acquiring a set of self-adaptive weight coefficients according to the slope safety factor and the plant parameter information to be detected; The inputting of the plant parameter information to be detected into the plant root anchoring effect index model, thereby acquiring a plant root anchoring effect index comprises: inputting the set of self-adaptive weight coefficients and the plant parameter information to be detected into the plant root anchoring effect index model, thereby acquiring a plant root anchoring effect index.

4. The plant root anchoring effect applicability acquisition method according to claim 3, wherein The plant root anchoring effect index model is as follows: ； Wherein, RREI is a plant root anchoring effect index; is the normalized plant parameter information to be detected; is a slope safety factor; is a minimum value of the slope safety factor; is a maximum value of the slope safety factor; is a weight coefficient.

5. The plant root anchoring effect applicability acquisition method according to claim 4, wherein The basic parameters of the land to be transplanted comprise an internal friction angle, a cohesion, a slope geometric parameter and a water characteristic curve; The acquiring of the micro root-soil composite equivalent shear strength according to the basic parameters of the land to be transplanted comprises: acquiring root-soil interface crack propagation parameters and a critical crack length according to the basic parameters of the land to be transplanted and the plant parameter information to be detected; generating micro root-soil interface equivalent shear strength according to the root-soil interface crack propagation parameters and the water characteristic curve.

6. The plant root anchoring effect applicability acquisition method according to claim 5, wherein The acquiring of the meso root-soil composite equivalent shear strength and the root length density according to the basic parameters of the land to be transplanted comprises: establishing a root-soil composite two-dimensional model using FLAC3D, defining a root distribution area, and assigning root parameters and soil parameters; performing mechanical response simulation on the root-soil composite two-dimensional model, thereby acquiring meso root-soil composite equivalent shear strength and root length density.

7. The plant root anchoring effect applicability range acquisition method according to claim 6, wherein The acquiring of the slope safety factor according to the micro root-soil composite equivalent shear strength, the meso root-soil composite equivalent shear strength and the root length density comprises: constructing a dynamic root-soil composite constitutive model; acquiring a corrected internal friction angle according to the internal friction angle; acquiring a corrected cohesion according to the cohesion; acquiring a slope safety factor according to the dynamic root-soil composite constitutive model, the corrected internal friction angle, the corrected cohesion and the slope geometric parameter.

8. The plant root anchoring effect applicability acquisition method according to claim 7, wherein The acquiring of the slope safety factor according to the dynamic root-soil composite constitutive model, the corrected internal friction angle, the corrected cohesion and the slope geometric parameter comprises: The meso-scale finite element model is constructed, and the meso-scale finite element model comprises: generating a slope surface according to a slope angle, a height and a platform width through a geometric projection method; generating randomly distributed beam elements in soil according to a root distribution depth, and the direction of the beam elements is subject to a statistical distribution of a branching angle β; constructing a root constitutive relationship and a soil constitutive relationship; performing grid division, and the grid division principles comprise: using a structured hexahedral grid in a root area; using an unstructured tetrahedral grid in a non-root area, and the element size gradually increases from the root boundary outward; displacement constraints comprise: fixing the bottom and applying rolling support to the lateral boundary; load application comprises: applying a gravity load to the top and gradually loading in 10 load steps; performing iterative calculation through a finite element solver, and outputting a soil strain distribution chart and stress field data; Based on the soil strain distribution chart output by the meso-scale finite element model, a strain energy density criterion is used to define a region with a strain of greater than 0.5% as a high strain region; The high strain region is sampled at equal intervals along the slope direction, and each sampling point corresponds to an initial sliding surface, and the sliding surface shape is a circular arc, so that an initial sliding surface set is obtained; The initial sliding surface set is optimized through a genetic algorithm, so that optimal sliding surface control point coordinates and a minimum safety factor are obtained, and the minimum safety factor is used as the slope safety factor.

9. The plant root anchoring effect applicability acquisition method according to claim 8, wherein When the initial sliding surface set is optimized through the genetic algorithm, the fitness function used is as follows: ; wherein, ， wherein, is the safety factor of the slope; is the corrected soil cohesion; b is the strip width; is the shear strength of the root-soil complex; is the corrected tangent of the soil internal friction angle; is the soil density; g is the acceleration of gravity; z is the strip depth; is the sine of the strip inclination.

10. A device for determining the applicable range of plant root anchoring effect, characterized in that, The plant root anchoring effect applicable range acquisition device comprises: Undetected plant parameter information acquisition module, the undetected plant parameter information acquisition module is used for acquiring undetected plant parameter information; Model acquisition module, the model acquisition module is used for acquiring a plant root anchoring effect index model; Effect index calculation module, the effect index calculation module is used for inputting the undetected plant parameter information into the plant root anchoring effect index model, so as to acquire a plant root anchoring effect index; A reference table acquisition module is used to acquire an index recommendation reference table, the index recommendation reference table comprising at least one preset numerical interval and the corresponding application recommendation of each preset numerical interval; An application recommendation acquisition module is used to acquire the application recommendation corresponding to the preset numerical interval where the plant root anchoring effect index is located.

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