Device and method for measuring and calculating pulling resistance of slope protection irrigation grass root system

Abstract

The invention relates to the technical field of plant root system pulling resistance simulation, and particularly discloses a device and method for measuring and calculating slope protection irrigation root system pulling resistance, and the device comprises a planting disc, a support assembly, a vertical lifting mechanism, a dynamometer, a pull rope and a displacement observation part. A screening structure is arranged at the bottom of the planting plate to allow a root system to grow downwards; the bracket assembly is used for providing stable support in a slope environment; the vertical lifting mechanism is arranged on the support assembly and provides controllable vertical lifting driving force. The dynamometer is connected with the vertical lifting mechanism and is used for measuring the pulling force applied to the planting plate; the pull rope is connected with the planting plate and the dynamometer and transmits vertically upward pulling force; the displacement observation part is arranged on the vertical lifting mechanism and is used for synchronously observing the displacement of the planting plate in the drawing process. The device can adapt to the slope environment, synchronous dynamic measurement of pulling force and displacement is achieved, and comprehensive data is provided for root system pulling resistance measurement and soil fixation mechanical analysis.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plant root resistance simulation, and in particular to a device and method for measuring and calculating the root resistance of slope protection shrubs and grasses. BACKGROUND

[0002] Plant roots enhance soil shear resistance through root-soil interface friction and their own tensile strength, which is the core mechanism for achieving slope reinforcement and soil and water conservation in the field of ecological slope protection. Accurate quantification of root resistance is of great theoretical and practical significance for predicting the critical sliding force of vegetation-reinforced slopes, optimizing vegetation configuration to reduce soil erosion, and evaluating the anchoring effect of roots in shallow landslides.

[0003] Currently, the study of root soil reinforcement mechanical properties usually starts with single root tensile testing, which can be used to determine basic mechanical parameters such as tensile strength of roots of different species. However, single root testing cannot reflect the actual soil reinforcement effect of numerous roots interwoven and acting together when plants grow in situ in actual soil. Therefore, conducting group root tensile tests to measure the actual restraining force and pullout resistance of plant roots on soil in situ has become a research direction that is closer to the actual needs of the engineering field.

[0004] Although group root tensile testing is a technical advancement, existing in-situ root pullout resistance measurement devices and methods still have obvious limitations. First, most existing devices (such as the scheme disclosed in CN107796550A) use fixed support structures that are difficult to adapt to complex terrains such as slopes, and cannot meet the needs of convenient in-situ measurement of slope plant root pullout resistance. Second, existing technologies usually only record the initial pullout force and the peak pullout force at the time of rupture, and cannot obtain dynamic data of continuous changes in pullout force during the entire pullout process, losing key information reflecting the deformation and destruction process of roots. More importantly, existing devices generally lack the function of synchronous and accurate measurement of displacement during the pullout process. Since the deformation of roots during the force process and the dynamic changes in root-soil interface friction caused by the deformation are ignored, the completeness and accuracy of the data obtained by existing methods are limited, making it difficult to analyze the mechanical mechanism of root soil reinforcement.

[0005] In summary, there is currently a lack of a portable and reliable device and supporting method that can be used in slope environments and can simultaneously and dynamically measure the in-situ pullout resistance and corresponding displacement of slope protection shrubs and grasses. SUMMARY

[0006] In view of the problems existing in the prior art, the present application provides a device and method for measuring and calculating the root resistance of slope protection shrubs and grasses, which is low in cost, easy to operate and carry.

[0007] As a first aspect of the present invention, the present invention provides a device for measuring the pull-out resistance of the root system of slope protection shrubs and grasses, comprising: a planting tray for in-situ cultivation of plants, the bottom of which is provided with a screening structure that allows the plant roots to grow downwards; a support assembly for providing stable support in a slope environment; a vertical lifting mechanism disposed on the support assembly for providing a controllable vertical lifting driving force; a force gauge connected to the vertical lifting mechanism for measuring the tension applied to the planting tray; a pull rope connected between the planting tray and the force gauge for transmitting the vertically upward tension; and a displacement observation component disposed on the vertical lifting mechanism for synchronously observing the displacement of the planting tray during the pull-out process.

[0008] Optionally, the screening structure of the planting tray includes a first layer of mesh at its bottom and a second layer of screen covering and fixed on the first layer of mesh with a smaller aperture than the first layer of mesh, so as to screen roots of a specific diameter range to pass through.

[0009] Optionally, the second layer of screen is a nylon mesh with an aperture of 1.0mm to 5.0mm.

[0010] Optionally, the planting tray is a square stainless steel tray or a round stainless steel mesh screen.

[0011] Optionally, the support assembly includes an adjustable camera tripod with independently adjustable legs and a support connector fixed to its top, and the vertical lifting mechanism is detachably mounted on the support connector.

[0012] Optionally, the vertical lifting mechanism includes:

[0013] The lifting outer cylinder is fixedly connected to the bracket connecting seat;

[0014] A movable inner cylinder is fitted inside the outer cylinder and can slide vertically. The inner cylinder has a rack arranged longitudinally on its side.

[0015] The lifting drive mechanism has a metal gear at its drive end that meshes with the rack and pinion, used to drive the inner cylinder to lift and lower.

[0016] Optionally, the displacement observation component includes a transparent cylinder fixed to the top of the lifting outer cylinder, and a displacement scale line is provided on the cylinder wall of the transparent cylinder; the force gauge is fixed to the top of the lifting inner cylinder, and its bottom can be accommodated by the transparent cylinder, and the displacement is read by observing the position change of the bottom of the force gauge relative to the displacement scale line.

[0017] Optionally, the pull rope is a steel wire rope, with its upper end connected to the force gauge and its lower end reliably connected to the corner of the planting tray via multiple plastic-coated steel wire ropes and steel wire rope locks.

[0018] As a second aspect of the present invention, the present invention provides a method for measuring the pull-out resistance of the root system of slope protection shrubs and grasses, based on the apparatus for measuring the pull-out resistance of the root system of slope protection shrubs and grasses described in the first aspect above, the method comprising the following steps:

[0019] S1: Experiment preparation, selection of target plant seeds and sifted planting soil;

[0020] S2: In-situ cultivation and installation: compact the planting tray onto the surface of the slope soil, fill it with planting soil and sow the seeds;

[0021] S3: Maintenance and management to promote plant growth until enough roots penetrate the bottom of the planting tray and enter the soil below;

[0022] S4: Measurement device installation: A support assembly is stably erected next to the planting tray, and the planting tray is connected to the force gauge by a pull rope;

[0023] S5: Measurement system settings, connect the force gauge to the data acquisition device and set it to real-time recording mode;

[0024] S6: Synchronous pulling and data recording. The planting tray is pulled up at a constant speed by a vertical lifting mechanism. The data acquisition device continuously records the pulling force change curve. At the same time, the operator records the displacement change ΔL corresponding to the peak pulling force through the displacement observation component until the root system is completely broken or pulled out.

[0025] S7: Data Acquisition and Mechanical Parameter Calculation. Based on recorded tensile data and measured root morphology parameters, calculate one or more of the following parameters: net pull-out force, total cross-sectional area of ​​root bundle, average tensile strength, ultimate strain, elastic modulus, and average frictional resistance at the root-soil interface.

[0026] Optionally, in step S7:

[0027] The net pull-out force F is calculated using the following formula: F = F max - F final , where F max F represents the maximum tensile force during the entire drawing process. final The stable reading of the force gauge after the root system has been completely pulled out or broken;

[0028] The average tensile strength σ of the root bundle is calculated by the following formula: σ = F / A, where F is the net pull-out force and A is the total cross-sectional area of ​​all roots extending into the soil.

[0029] The ultimate strain ε is calculated by the following formula: ε = ΔL / L, where ΔL is the displacement change at the peak tensile force and L is the average root length of all roots extending into the soil.

[0030] The elastic modulus E is estimated by the following formula: E = σ / ε, where σ is the average tensile strength and ε is the ultimate strain;

[0031] The average frictional resistance f per unit area at the root-soil interface is estimated using the following formula: f = F / (π × D) avg × L total ), where F is the net pull-out force, and D avg L is the average diameter of all roots extending into the soil. total This represents the total length of all roots extending into the soil.

[0032] Compared with the prior art, the present invention discloses at least the following beneficial effects:

[0033] This invention, by setting up a planting tray with a screening structure at the bottom, can cultivate slope-protecting shrubs and grasses in situ on slopes and select roots of a specific diameter range to grow downwards, thereby ensuring that the test specifically reflects the soil-fixing contribution of the target root system. The use of a support assembly with independently adjustable legs allows the device to be stably supported on complex terrains such as slopes, overcoming the limitations of existing fixed supports that are difficult to adapt to outdoor slope environments. Combined with a vertical lifting mechanism set on the support, it can provide controllable and stable vertical lifting driving force. A vertical upward pulling force is applied to the planting tray by a pull rope, and the pull force change is measured in real time and continuously by a connected force gauge, thereby dynamically acquiring the pull force data from the entire process from loading to root damage, completely preserving key information reflecting the root deformation and damage mechanism. At the same time, a displacement observation component integrated on the vertical lifting mechanism can synchronously observe and record the displacement of the planting tray during the pulling process, realizing synchronous dynamic and accurate measurement of pull force and displacement. The synergistic effect of the above structures makes the device not only easy to install and operate quickly in situ on slopes, but also able to synchronously, continuously, and in situ acquire the full-process tension-displacement curve of the roots of the slope protection shrub and grass group during the tensile process. This provides a reliable and comprehensive data foundation for accurately quantifying the root pull-out force, deeply analyzing the dynamic changes of the root-soil interface friction state and the root soil stabilization mechanism, and effectively solves the problems of existing technologies that are difficult to adapt to slope environments, have discontinuous data recording, and lack synchronous displacement measurement functions. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a front view of the device for measuring the pull-out resistance of slope protection shrub roots provided in Embodiment 1 of the present invention;

[0036] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0037] Figure 3 This is a right view of the device for measuring the pull-out resistance of slope protection shrub roots provided in Embodiment 1 of the present invention;

[0038] Figure 4 This is an isometric view of the device for measuring the pull-out resistance of slope protection shrub roots provided in Embodiment 1 of the present invention;

[0039] Figure 5 This is a disassembly diagram of the device in Embodiment 1 of the present invention;

[0040] Figure 6 This is an isometric view of the device for measuring the pull-out resistance of the root system of slope protection shrubs provided in Embodiment 2 of the present invention.

[0041] In the diagram: 1. Planting tray; 2. Plastic-coated steel wire rope; 3. Steel wire rope lock; 4. Adjustable camera tripod; 5. Bracket connector; 6. Locking nut cap; 7. Lifting outer cylinder; 8. Lifting inner cylinder; 9. Lifting drive mechanism; 10. Force gauge; 11. Displacement scale line; 12. Pull rope; 13. Metal gear; 14. Rack; 15. Nylon mesh; 16. Vertical adjustment handle. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Example 1

[0045] Reference Figures 1 to 5 As shown, Embodiment 1 of the present invention provides a device for measuring the pull-out force of the root system of slope protection shrubs. The device is a portable structure that is easy to assemble and measure in situ on complex terrains such as slopes. It mainly includes a planting tray 1 for in-situ cultivation of plants, a support assembly for providing stable support and controllable lifting, a pull rope 12 for transmitting tension, and a force gauge 10 for measuring tension.

[0046] In one specific embodiment, the planting tray 1 is a key component for cultivating plants and allowing their roots to extend into the native soil below. In this embodiment, the planting tray 1 is a square stainless steel tray structure. The structure has an opening at the top for easy filling with soil and planting. Its bottom is uniformly provided with multiple circular mesh openings, for example, 5mm in diameter, to allow roots to pass through. To differentiate and restrict roots of different diameters, a layer of nylon mesh 15 is further covered and fixed to the bottom of the square stainless steel tray. The mesh diameter of the nylon mesh 15 is smaller than that of the circular mesh openings at the bottom of the stainless steel tray. Its specific specifications can be selected according to the research objectives; for example, nylon mesh 15 with a mesh diameter of 1.0mm or 2.0mm can be used. This effectively ensures that only fine roots with a diameter less than or equal to this mesh diameter can pass through the nylon mesh 15 and grow downwards into the soil. The nylon mesh 15 is tightly bound to the bottom of the tray with fasteners such as nylon cable ties to ensure stability during subsequent pulling processes, preventing slippage or damage. The planting tray 1 designed in this way can cultivate slope protection shrubs and grasses in situ on the slope, and select fine roots with a specific diameter range (such as ≤1.0mm or ≤2.0mm) to participate in the pull-out resistance test, laying the foundation for studying the soil stabilization contribution of different root diameter levels.

[0047] In one specific embodiment, the support assembly is the core of the entire device's support and power. Its main body is a modified adjustable camera tripod 4 with independently adjustable legs, represented as a support in the figure. A support connecting seat 5 is provided at the top of the support, on which a vertical lifting mechanism is fixedly mounted. Specifically, the support connecting seat 5 is a cylindrical structure, its bottom connected to the legs of the adjustable camera tripod 4. The outer surface of the cylinder near the top has external threads to cooperate with the locking nut cap 6 for threaded connection. The support connecting seat 5 is hollow inside, with a cavity through which the lifting inner cylinder 8 of the vertical lifting mechanism freely passes.

[0048] In one specific embodiment, the vertical lifting mechanism includes a lifting outer cylinder 7 fixedly connected to the bracket connecting seat 5, and a lifting inner cylinder 8 movably sleeved inside the lifting outer cylinder 7 and capable of sliding relative to it in the vertical direction. A rack 14 is longitudinally arranged on the side of the lifting inner cylinder 8. In this embodiment, the lifting inner cylinder 8 is connected to the lifting drive mechanism 9 through its internal gear transmission structure, and the lifting drive mechanism 9 can drive the lifting inner cylinder 8 to rise and fall. The top of the lifting inner cylinder 8 is open, and its interior has a longitudinally penetrating through-hole structure.

[0049] Based on the above embodiments, to further ensure smooth lifting and durability, the lifting drive mechanism 9 includes a servo motor fixed on the outer cylinder 7 of the lifting mechanism. The motor shaft of the servo motor is connected to a metal gear 13, which meshes with a rack 14. The rotation of the servo motor enables more precise and labor-saving lifting control.

[0050] In one specific embodiment, the force gauge 10 is fixed to the top of the lifting inner cylinder 8, preferably a digital push-pull force gauge, which has a data output interface and can be connected to external devices such as laptops. It uses dedicated software to collect, display, and record the dynamic curve of the tension changing over time in real time. During measurement, the force gauge 10 is vertically installed at the top of the lifting inner cylinder 8. A hook is connected to the lower end of the force gauge 10, extending downwards into the longitudinal through-hole of the lifting inner cylinder 8. Multiple plastic-coated steel wire ropes 2 are connected to the hook via pull ropes 12, with the ends of each plastic-coated steel wire rope 2 connected to the corner of the planting tray 1.

[0051] It should be understood that the pull rope 12 is used to connect the planting tray 1 and the force gauge 10 to transmit a vertically upward pulling force. The pull rope 12 is preferably a steel wire rope with flexibility and high strength. The upper end of the pull rope 12 passes through the through hole of the lifting inner cylinder 8 and is connected to the hook of the force gauge 10; the lower end of the pull rope 12 is connected to the plastic-coated steel wire rope 2, and the plastic-coated steel wire rope 2 is reliably connected to the planting tray 1.

[0052] Based on the above embodiments, in order to prevent the connection point from slipping during the pulling process, steel wire rope locks 3 of corresponding size are used to fix and lock the connection between the pull rope 12 and the hooks of the planting tray 1 and the force gauge 10.

[0053] In one specific embodiment, a large-capacity transparent plastic tube is fixed to the top of the lifting outer cylinder 7 with screws, or the transparent plastic tube is integrally formed. This transparent plastic tube is preferably a modified plastic syringe barrel with graduations, and its wall has displacement scale lines 11. The primary function of this transparent plastic tube is to act as a protective and guiding sleeve, accommodating the lower part of the force gauge 10 and preventing it from accidentally falling from the top of the lifting inner cylinder 8 during the pulling process. Secondly, since the tube is fixed to the lifting outer cylinder 7, and the force gauge 10 and the connected lifting inner cylinder 8 move relative to the lifting outer cylinder 7, the operator can visually read and record the sliding displacement of the lifting inner cylinder 8 relative to the lifting outer cylinder 7 by observing the positional change of the bottom end of the force gauge 10 relative to the displacement scale lines 11 on the transparent plastic tube. This displacement is approximately equal to the displacement of the planting tray 1 below when it is pulled upwards.

[0054] The device provided in this embodiment can be stably erected on a slope through an adjustable bracket; through the combination of a vertical lifting mechanism and a force gauge 10, a stable and controllable vertical upward pulling load on the planting tray 1 is achieved; and through the data recording of the force gauge 10 and the displacement observation of the transparent plastic tube, synchronous dynamic measurement of tension and displacement is achieved, providing an effective tool for in-situ and accurate calculation of the root pull-out force and its related mechanical parameters.

[0055] Example 2

[0056] Reference Figure 6As shown, Embodiment 2 of the present invention provides a device for measuring the pull-out resistance of the root system of slope protection shrubs. The main difference between it and Embodiment 1 lies in the structural design of the planting tray 1, which is designed to specifically study the pull-out resistance performance within a specific range of fine root diameters. The structure, connection relationship, and function of other components of the device, such as the support, vertical lifting mechanism, force gauge 10, and pull rope 12, are the same as those in Embodiment 1, and will not be described again here.

[0057] In this embodiment, the planting tray 1 has a circular structure, specifically a circular stainless steel mesh screen. The bottom of this circular stainless steel mesh screen is evenly distributed with circular mesh openings of uniform diameter, preferably 2 mm. This integrated design eliminates the need for an additional nylon mesh 15; the mesh itself serves as a screening mechanism, allowing only fine plant roots with a diameter less than or equal to 2 mm to penetrate the soil below, while larger roots are confined within the tray. This structure is particularly suitable for studying the pull-out resistance of roots within a specific fine root diameter range (e.g., ≤2 mm) and their soil-stabilizing effect. The circular structure also allows for a more uniform stress distribution under load.

[0058] In this embodiment, a vertical adjustment handle 16 is connected to the lifting drive mechanism 9. The vertical adjustment handle 16 can replace or take over the servo motor. The vertical adjustment handle 16 is adopted as a preferred way to manually adjust the vertical lifting mechanism. By rotating the handle at a uniform speed, the metal gear 13 is driven to drive the lifting inner cylinder 8 to rise smoothly.

[0059] Example 3

[0060] Embodiment 3 of the present invention also provides a method for measuring the pull-out resistance of the root system of slope protection shrubs and grasses. Based on the device for measuring the pull-out resistance of the root system of slope protection shrubs and grasses described in Embodiment 1 or Embodiment 2 above, the method includes the following steps:

[0061] S1: Experiment preparation.

[0062] Select seeds of target slope protection shrubs and grasses, such as hardy and drought-resistant sea buckthorn (Hippophae rhamnoides) seeds. Prepare sieved planting soil, such as purple soil that has passed through a 2mm standard sieve.

[0063] S2: In situ culture and installation.

[0064] Place planting tray 1 and compact it firmly onto the soil surface at the slope test point, ensuring close contact between the bottom of the tray and the soil. Fill the tray with prepared planting soil and sow plant seeds (e.g., 5 sea buckthorn seeds per planting tray 1).

[0065] S3: Maintenance and management.

[0066] Water and fertilize regularly to promote plant growth. Observe and record how the plant roots penetrate the bottom of the planting tray 1 (mesh or nylon mesh 15) and extend into the native soil below.

[0067] S4: Measurement device installation.

[0068] Once the plant has grown enough roots to penetrate the soil, set up a support frame next to the planting tray 1 and adjust its legs to stabilize it on the slope. Securely connect the lower end of the pull rope 12 to the planting tray 1 via the wire rope lock 3, and connect the upper end through the lifting inner cylinder 8 to the hook of the force gauge 10 and lock it in place.

[0069] S5: Measurement system settings.

[0070] Connect the force gauge 10 to the laptop via a data cable, start the accompanying data acquisition software, and set it to real-time recording mode.

[0071] S6: Synchronous pull-out and data recording.

[0072] The vertical adjustment handle 16 of the vertical lifting mechanism is rotated at a constant speed, or the servo motor is controlled to operate, causing the inner lifting cylinder 8 and the force gauge 10 to rise at a constant speed, thereby applying a vertical upward pulling force to the planting tray 1 through the pull rope 12. The software continuously records the force change curve throughout the entire pulling process. At the same time, the operator visually observes and records the displacement change ΔL of the bottom end of the force gauge 10 relative to the displacement scale line 11 on the transparent plastic cylinder when the pulling force reaches its peak (maximum value). Pulling continues until all roots extending into the soil are completely broken or pulled out of the soil.

[0073] S7: Data acquisition and mechanical parameter calculation.

[0074] Calculate the net pull-out force F: Read the maximum tensile force F from the software records throughout the entire pull-out process. max Read the stable reading F of the force gauge 10 after the root system has been completely pulled out or broken. final (This value is approximately the weight of planting tray 1, the soil within the tray, and the above-ground parts of the plant). Net pull-out force F = F max - F final .

[0075] Root morphology parameter measurement: Carefully collect all roots that have been pulled out of the soil or broken off and that have extended into the soil. Cut the roots close to the bottom of planting tray 1 and wash them while they are fresh. Use calipers and a ruler to measure the diameter d and length l of each root.

[0076] Calculate the total cross-sectional area A: Based on the diameter d of each root, calculate the cross-sectional area of ​​a single root: a = π×(d / 2) 2 Adding up the cross-sectional areas of all roots extending into the soil, we get the total cross-sectional area of ​​the root bundle, A = Σa.

[0077] Calculate the tensile strength σ: Use the formula σ = F / A to calculate the average tensile strength of the root bundle.

[0078] Calculate the ultimate strain ε: Calculate the average root length L = (Σl) / n of all roots extending into the soil, where n is the number of roots. Use the formula ε = ΔL / L to calculate the ultimate strain of the root system when it reaches maximum tensile force.

[0079] Calculate the elastic modulus E: Use the formula E = σ / ε to estimate the elastic modulus of the root bundle.

[0080] Calculate the interfacial frictional resistance f: Calculate the average diameter D of all roots extending into the soil. avg = (Σd) / n. Using the formula f = F / (π × D) avg × L total Estimate the average frictional resistance per unit area at the root-soil interface, where L total = Σl is the total length of the root system.

[0081] Through the above steps, this method can not only measure the maximum pull-out force of plant roots in situ, but also simultaneously obtain the tensile-displacement curve reflecting the entire failure process, and further calculate several key mechanical parameters such as tensile strength, ultimate strain, elastic modulus, and interfacial friction resistance. This comprehensive and dynamic data provides direct and reliable data support for the scientific quantitative assessment of the soil-fixing capacity of slope protection plant roots, the prediction of slope stability, and the optimization of vegetation configuration schemes.

[0082] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0083] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A device for measuring the pull-out resistance of shrubs and grasses on slopes, characterized in that, include: Planting tray (1) is used for in-situ cultivation of plants and has a screening structure at the bottom that allows plant roots to grow downwards; Support components are used to provide stable support in sloping environments; A vertical lifting mechanism, mounted on the bracket assembly, provides a controllable vertical lifting driving force; A force gauge (10) is connected to the vertical lifting mechanism and is used to measure the tension applied to the planting tray (1); A pull rope (12) is connected between the planting tray (1) and the force gauge (10) to transmit a vertically upward pulling force; A displacement observation component is installed on the vertical lifting mechanism to synchronously observe the displacement of the planting tray (1) during the pulling process.

2. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 1, characterized in that, The screening structure of the planting tray (1) includes a first layer of mesh at its bottom and a second layer of screen covering and fixed on the first layer of mesh with a smaller aperture than the first layer of mesh, so as to screen roots of a specific diameter range to pass through.

3. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 2, characterized in that, The second layer of screen is nylon mesh (15) with a pore size of 1.0mm~5.0mm.

4. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 2, characterized in that, The planting tray (1) is a square stainless steel tray or a round stainless steel mesh screen.

5. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 1, characterized in that, The bracket assembly includes an adjustable camera tripod (4) with independently adjustable legs and a bracket connector (5) fixed on its top, and the vertical lifting mechanism is detachably mounted on the bracket connector (5).

6. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 1 or 5, characterized in that, The vertical lifting mechanism includes: The lifting outer cylinder (7) is fixedly connected to the bracket connecting seat (5); A lifting inner cylinder (8) is movably fitted inside the lifting outer cylinder (7) and can slide in the vertical direction. A rack (14) is provided on the side of the lifting inner cylinder (8) in the longitudinal direction. The lifting drive mechanism (9) has a metal gear (13) at its drive end that meshes with the rack (14) to drive the lifting inner cylinder (8) to lift.

7. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 6, characterized in that, The displacement observation component includes a transparent cylinder fixed to the top of the lifting outer cylinder (7), and a displacement scale line (11) is provided on the cylinder wall of the transparent cylinder; the force gauge (10) is fixed to the top of the lifting inner cylinder (8), and its bottom can be accommodated by the transparent cylinder. The displacement is read by observing the position change of the bottom of the force gauge (10) relative to the displacement scale line (11).

8. The device for measuring the pull-out resistance of slope protection shrubs and grasses according to claim 6, characterized in that, The pull rope (12) is a steel wire rope, with its upper end connected to the force gauge (10) and its lower end reliably connected to the corner of the planting tray (1) through multiple plastic-coated steel wire ropes (2) and steel wire rope locks (3).

9. A method for measuring the pull-out resistance of shrub and grass roots on slopes, based on the apparatus for measuring the pull-out resistance of shrub and grass roots on slopes according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Experiment preparation, selection of target plant seeds and sifted planting soil; S2: In-situ cultivation and installation: compact the planting tray (1) onto the surface of the slope soil, fill it with planting soil and sow seeds; S3: Maintenance and management to promote plant growth until enough roots penetrate the bottom of the planting tray (1) and enter the soil below; S4: Measuring device installation: A support assembly is stably erected next to the planting tray (1), and the planting tray (1) is connected to the force gauge (10) by a pull rope (12); S5: Measurement system settings, connect the force gauge (10) to the data acquisition device and set it to real-time recording mode; S6: Synchronous pulling and data recording. The planting tray (1) is pulled up at a constant speed through the vertical lifting mechanism. The data acquisition device continuously records the pulling force change curve. At the same time, the operator records the displacement change ΔL corresponding to the peak pulling force through the displacement observation component until the root system is completely broken or pulled out. S7: Data Acquisition and Mechanical Parameter Calculation. Based on recorded tensile data and measured root morphology parameters, calculate one or more of the following parameters: net pull-out force, total cross-sectional area of ​​root bundle, average tensile strength, ultimate strain, elastic modulus, and average frictional resistance at the root-soil interface.

10. The method for measuring the pull-out resistance of shrub and grass roots on a slope according to claim 9, characterized in that, In step S7: The net pull-out force F is calculated using the following formula: F = F max - F final , where F max F represents the maximum tensile force during the entire drawing process. final The stable reading of the force gauge (10) after the root system is completely pulled out or broken; The average tensile strength σ of the root bundle is calculated by the following formula: σ = F / A, where F is the net pull-out force and A is the total cross-sectional area of ​​all roots extending into the soil. The ultimate strain ε is calculated by the following formula: ε = ΔL / L, where ΔL is the displacement change at the peak tensile force and L is the average root length of all roots extending into the soil. The elastic modulus E is estimated by the following formula: E = σ / ε, where σ is the average tensile strength and ε is the ultimate strain; The average frictional resistance f per unit area at the root-soil interface is estimated using the following formula: f = F / (π × D) avg × L total ), where F is the net pull-out force, and D avg L is the average diameter of all roots extending into the soil. total This represents the total length of all roots extending into the soil.

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