A root anchorage force dynamic testing device based on acoustic emission identification under controllable vibration condition

Abstract

This invention relates to the field of plant root mechanical performance testing technology, and particularly to a dynamic testing device for root anchorage force based on acoustic emission identification under controllable vibration conditions. The device includes a transparent box, a hydraulic longitudinal loading unit, an acoustic emission monitoring unit, and a control system. The transparent box is filled with soil for planting the plant under test. The hydraulic longitudinal loading unit includes a hydraulic servo vibration cylinder, a tension / compression sensor, and a clamp. The hydraulic servo vibration cylinder is positioned above the transparent box, and the bottom end of its piston rod is connected to the tension / compression sensor. The tension / compression sensor is connected to the stem of the plant under test via the clamp. The hydraulic servo vibration cylinder, tension / compression sensor, and acoustic emission sensor are all electrically connected to the control system. This invention uses a hydraulic servo vibration cylinder to output a longitudinal vibration load superimposed with a pull-out bias, which can simulate the root stress state under actual dynamic environments such as wind vibration, water flow pulsation, and seismic disturbance.

Description

Technical Field

[0001] This invention relates to the field of plant root mechanical property testing technology, and in particular to a dynamic testing device for root anchoring force based on acoustic emission recognition under controllable vibration conditions. Background Technology

[0002] The anchoring characteristics of plant roots are a core indicator for slope protection, soil and water conservation, and risk assessment of urban trees. In nature, roots rarely bear purely static loads; wind vibration, water flow pulsation, and earthquakes all manifest as alternating or transient dynamics superimposed on a stable tensile force. However, traditional root pull-out tests often employ quasi-static loading, only obtaining the maximum pull-out force and failing to reflect the fatigue damage and energy dissipation characteristics of roots under dynamic alternating forces. Acoustic emission technology can sensitively capture internal damage signals in materials, but currently, there is a lack of dedicated equipment that effectively integrates controllable longitudinal vibration loading with acoustic emission monitoring, especially in continuously and in real-time measuring changes in root anchoring force while simulating dynamic loads. Furthermore, conventional soil boxes are opaque, making it impossible to observe the interaction and deformation characteristics of roots with the soil during vibration and pull-out processes in real time, limiting in-depth mechanistic research.

[0003] For the reasons mentioned above, this invention discloses a dynamic testing device for root anchorage force based on acoustic emission identification under controllable vibration conditions. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a dynamic testing device for root anchoring force based on acoustic emission recognition under controllable vibration conditions. The device outputs a longitudinal vibration load superimposed with a pull-out bias through a hydraulic servo vibration cylinder, so that the plant roots gradually bear an increasing pull-out effect under longitudinal vibration conditions, which can simulate the root stress state under actual dynamic environments such as wind vibration, water flow pulsation, and earthquake disturbance.

[0005] To achieve the above objectives, the technical solution adopted by this invention is as follows: This invention discloses a dynamic testing device for root anchoring force based on acoustic emission identification under controllable vibration conditions, comprising a transparent box, a hydraulic longitudinal loading unit, an acoustic emission monitoring unit, and a control system. The transparent box has a hollow square structure with an open top, and its interior is filled with soil for planting the plant under test. The side wall of the transparent box is provided with several mounting holes. The hydraulic longitudinal loading unit includes a hydraulic servo vibration cylinder, a tension / compression sensor, and a clamp. The hydraulic servo vibration cylinder is positioned above the transparent box, and the bottom end of the piston rod of the hydraulic servo vibration cylinder is connected to the tension / compression sensor. The tension / compression sensor is connected to the stem of the plant under test through the clamp. The acoustic emission monitoring unit includes several acoustic emission sensors buried in the soil through the mounting holes. The hydraulic servo vibration cylinder, the tension / compression sensor, and the acoustic emission sensor are all electrically connected to the control system.

[0006] The hydraulic longitudinal loading unit also includes a base and a gantry bracket. The transparent box is fixed to the middle of the upper surface of the base. The gantry bracket is an inverted "U" shaped structure composed of two side support columns and a top crossbeam. The bottom of the two side support columns is fixed to the two sides of the upper surface of the base. The two ends of the crossbeam are connected to the top of the two side support columns. The cylinder seat of the hydraulic servo vibration cylinder is fixed to the middle of the crossbeam.

[0007] A hydraulic pump is provided on one side of the gantry support. One end of the hydraulic pump is connected to an oil tank, and the other end is connected to one end of a hydraulic hose through a servo valve. The other end of the hydraulic hose is connected to the cylinder of the hydraulic servo vibration cylinder. The servo valve is electrically connected to the control system.

[0008] The clamp includes an axial connecting screw, a first clamping sleeve, a second clamping sleeve, a silicone pad, and a locking bolt. The first and second clamping sleeves are semi-circular ring structures, and silicone pads are provided on their inner walls. The silicone pads are semi-cylindrical structures with grooves for clamping stems on their inner sides. Ear plates are provided on both sides of the first and second clamping sleeves, and the ear plate holes on the ear plates are locked by the locking bolt and nuts. An axial connecting screw is provided above the first and second clamping sleeves. The external thread of the axial connecting screw is threaded to the threaded hole at the bottom of the tension / compression sensor. The bottom end of the axial connecting screw is fixedly connected to the middle of the top of the first clamping sleeve.

[0009] The transparent box is constructed by splicing transparent plexiglass, transparent tempered glass, or transparent acrylic sheet with a metal reinforcing frame. The front and at least one side of the transparent box are transparent observation surfaces, and the visible light transmittance of the transparent observation surfaces is not less than 90%. The seams are sealed with silicone sealant or sealing strips.

[0010] A sealing ring is provided at the mounting hole, and the housing of the acoustic emission sensor is sealed to the mounting hole by an O-ring. The sensitive surface of the acoustic emission sensor faces the root distribution area of ​​the plant being tested. Multiple acoustic emission sensors are arranged in a spatial array at different heights and different side wall positions of the transparent box. The control system has a built-in acoustic emission source positioning module. The acoustic emission source positioning module spatially locates the friction zone, slip zone, fracture zone, or root damage initiation zone of the root-soil interface based on the arrival time difference of the acoustic emission signals received by multiple acoustic emission sensors.

[0011] The hydraulic servo vibration cylinder is a double-acting hydraulic servo cylinder with a maximum output force of not less than 10kN, a working frequency of 0.1Hz to 30Hz, and an amplitude of ±0.1mm to ±15mm. It can output sine waves, triangular waves, square waves, swept waves, or random waves superimposed with slope pull-out bias. The tension and pressure sensor is a spoke-type bidirectional force sensor, an S-type bidirectional force sensor, or a column-type bidirectional force sensor with a range of 0 to 10kN and an accuracy of not less than 0.1%. It is used to simultaneously measure the dynamic alternating force and average pull-out force on the stem of the plant being tested.

[0012] It also includes a displacement field visual measurement system, which is set on the outside of the transparent box. The displacement field visual measurement system includes at least one of a high-speed camera, an industrial camera, a supplementary light source, and a digital image correlation analysis module, and is used for non-contact measurement of the soil surface displacement field, crack propagation path, and local deformation of the root-soil interface. The control system synchronizes the image data collected by the displacement field visual measurement system, the acoustic emission data collected by the acoustic emission monitoring unit, and the mechanical data collected by the tensile and compressive sensors in time to establish the correspondence between the displacement field, the acoustic emission source location, and the anchoring force attenuation.

[0013] This invention discloses a testing method for a dynamic testing device for root anchorage force based on acoustic emission identification under controllable vibration conditions, comprising the following steps: S1. Fill the transparent box with soil and plant the plant to be tested, so that the roots of the plant to be tested can grow or be fixed in the soil. S2. Bury multiple acoustic emission sensors in the soil near the roots through the mounting holes, and ensure that the acoustic emission sensors are tightly coupled to the soil. S3. The stem of the plant under test is held by a clamp, so that the plant under test is coaxially connected with the hydraulic servo vibration cylinder and the tension and compression sensor. S4. By setting the waveform, frequency and amplitude of the longitudinal vibration component and the rising rate of the pull-out component through the control system, the hydraulic servo vibration cylinder is controlled to apply a longitudinal vibration load with a pull-out bias to the plant under test. S5. During the loading process, tensile and compressive signals, displacement signals and acoustic emission signals are collected simultaneously, and the average tensile force component and dynamic force component are separated by filtering method. S6. Identify the root anchorage failure state based on at least one of the following: average tensile peak value, abrupt change in acoustic emission energy, change in acoustic emission event rate, dynamic stiffness decrease rate, and change in root-soil interface displacement field. S7 outputs vibration parameters, pull-out parameters, acoustic emission response, displacement field response, and dynamic attenuation curve of anchoring force.

[0014] The beneficial effects of this invention are as follows: 1. Capable of dynamic anchoring force testing under conditions of simultaneous vibration and pull-out. This invention outputs a longitudinal vibration load superimposed with a pull-out bias through a hydraulic servo vibration cylinder, so that the plant roots gradually bear an increased pull-out effect under longitudinal vibration conditions, which can simulate the root stress state under actual dynamic environments such as wind vibration, water flow pulsation, and earthquake disturbance.

[0015] 2. Capable of obtaining the entire process of root anchorage force attenuation in real time. The tension and compression sensors are connected in series with the hydraulic servo vibration cylinder to synchronously acquire dynamic alternating force and average pull-out force. The control system separates the dynamic force component and the average tension component through filtering, thereby obtaining the entire process curve of the root anchoring force changing with time, displacement, and vibration parameters.

[0016] 3. Able to identify root-soil interface damage using acoustic emission signals. Multiple acoustic emission sensors are buried in the soil near the roots, which can capture elastic wave signals generated by root-soil interface friction, slippage, debonding, soil crack expansion and root fracture in real time, so as to realize dynamic monitoring of root damage process.

[0017] 4. Capable of spatial positioning of acoustic emission sources The acoustic emission sensors are arranged in a spatial array. The control system locates the acoustic emission source based on the arrival time difference of the signals received by different sensors, which can determine the location of the damage, the propagation path and the area of ​​damage, thereby improving the ability to identify the root damage mechanism.

[0018] 5. Capable of enabling visual observation of the root-soil interface. The front and sides of the transparent box are transparent observation surfaces, which can be used with a high-speed camera or DIC digital image correlation system to perform non-contact measurements of soil surface displacement field, crack propagation path and local deformation of root-soil interface. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is the left view of the present invention; Figure 3 This is a schematic diagram of the fixture in this invention; Figure 4 This is a cross-sectional schematic diagram of the fixture in this invention.

[0020] In the attached diagram, 1 is a transparent box, 11 is a mounting hole, 2 is a hydraulic longitudinal loading unit, 21 is a hydraulic servo vibration cylinder, 22 is a tension / compression sensor, 23 is a clamp, 231 is an axial connecting screw, 232 is a first clamping sleeve, 233 is a second clamping sleeve, 234 is a silicone pad, 235 is a locking bolt, 236 is an ear plate, 24 is a base, 25 is a gantry bracket, 3 is an acoustic emission monitoring unit, 4 is a control system, 5 is the plant under test, 6 is a hydraulic pump, 7 is a hydraulic hose, and 8 is a displacement field visual measurement system. Detailed Implementation

[0021] The present invention will be further described below: Please see Figure 1-4 , Example 1: Basic Longitudinal Vibration Pull-out Testing Device like Figure 1 and Figure 2 As shown, this embodiment provides a dynamic testing device for root anchorage force based on acoustic emission identification under controllable vibration conditions, including a transparent box 1, a hydraulic longitudinal loading unit 2, an acoustic emission monitoring unit 3, and a control system 4.

[0022] The transparent box 1 is a hollow square structure with an open top, filled with soil in which the tested plant 5 is planted or fixed. Multiple mounting holes 11 are provided on the side walls of the transparent box 1 for mounting acoustic emission sensors. The transparent box 1 can be constructed from 10mm-15mm thick transparent acrylic or tempered glass panels, with an external aluminum alloy or stainless steel reinforcing frame to improve rigidity. All joints are sealed with silicone sealant to prevent leakage. The hydraulic longitudinal loading unit 2 includes a hydraulic servo vibration cylinder 21, a tension / compression sensor 22, a clamp 23, a base 24, and a gantry bracket 25. The transparent box 1 is fixed to the center of the upper surface of the base 24, and the gantry bracket 25 is positioned above the transparent box 1. The gantry bracket 25 includes two side support columns and a top crossbeam, forming an inverted "U" shape. The cylinder seat of the hydraulic servo vibration cylinder 21 is fixed to the center of the top crossbeam, and the piston rod of the hydraulic servo vibration cylinder 21 extends vertically downwards.

[0023] The bottom end of the piston rod of the hydraulic servo vibration cylinder 21 is connected to the tension / compression sensor 22, and the lower end of the tension / compression sensor 22 is connected to the stem of the plant 5 under test through the clamp 23. Thus, the longitudinal vibration and tensile load output by the hydraulic servo vibration cylinder 21 can be transmitted to the stem and root system of the plant 5 under test in sequence through the piston rod, the tension / compression sensor 22, and the clamp 23.

[0024] A hydraulic pump 6 and an oil tank are provided on one side of the gantry support 25. The hydraulic pump 6 is connected to the cylinder of the hydraulic servo vibration cylinder 21 through a servo valve and a hydraulic hose 7. The control system 4 controls the opening of the servo valve through an analog output card, thereby controlling the displacement, speed and loading waveform of the hydraulic servo vibration cylinder 21.

[0025] The acoustic emission monitoring unit 3 includes multiple acoustic emission sensors, a preamplifier, a multi-channel acoustic emission acquisition device, and signal lines. Multiple acoustic emission sensors are buried in the soil within the transparent box 1 through mounting holes 11, with their sensitive surfaces facing the root distribution area of ​​the tested plant 5. A coupling agent or silicone grease can be applied between the acoustic emission sensors and the soil to improve signal coupling. An O-ring is provided between the acoustic emission sensor housing and the mounting hole 11.

[0026] The control system 4 can be composed of an industrial computer, a data acquisition card, a motion control card, acoustic emission acquisition software, and loading control software. The control system 4 is electrically connected to the hydraulic servo vibration cylinder 21, the servo valve, the tension / compression sensor 22, and the acoustic emission sensor, respectively, and is used to control the loading process and synchronously acquire data.

[0027] During testing, the control system 4 sets composite loading parameters. For example, the longitudinal vibration component is a sine wave with a frequency of 5Hz and an amplitude of ±3mm; the pull-out component is a uniformly ascending ramp signal with a speed of 0.5mm / min to 5mm / min. The control system 4 superimposes the sine vibration signal and the ramp pull-out signal and outputs them to the servo valve. The servo valve controls the piston rod of the hydraulic servo vibration cylinder 21 to slowly move its equilibrium position upward while the piston rod reciprocates longitudinally, thereby achieving a composite loading of "vibration and pull-out" on the five roots of the tested plant.

[0028] During loading, tension and compression sensors 22 collect tension and compression signals in real time. The control system 4 extracts the average tension component through low-pass filtering and the dynamic force component through high-pass filtering. The acoustic emission monitoring unit 3 simultaneously collects acoustic emission signals generated by root-soil interface friction, slippage, soil crack propagation, and root fracture. When the average tension reaches its peak and then decreases, or when there is a sustained surge in acoustic emission energy or event rate, it can be determined that the root anchorage has entered the failure stage.

[0029] Example 2: Fixture Structure like Figure 3 and Figure 4 As shown, the clamp 23 includes an axial connecting screw 231, a first clamping sleeve 232, a second clamping sleeve 233, a silicone pad 234, a locking bolt 235, and an ear plate 236.

[0030] Both the first clamping sleeve 232 and the second clamping sleeve 233 are semi-circular ring structures, forming a cylindrical clamping cavity when they are joined together. The inner walls of both the first clamping sleeve 232 and the second clamping sleeve 233 are provided with silicone pads 234. The inner wall of the silicone pad 234 forms a groove for clamping the outer surface of the stem. The groove is arc-shaped, and its inner diameter is smaller than the outer diameter of the stem of the plant being tested. The silicone pad 234 is preferably a high-friction coefficient silicone rubber pad with a thickness of 3mm to 5mm.

[0031] Both sides of the first clamping sleeve 232 and the second clamping sleeve 233 are provided with ear plates 236, and the ear plates 236 are locked together by locking bolts 235 and nuts. By adjusting the preload of the locking bolts 235, it can accommodate plant stems of different diameters and avoid local pressure damage to the stem epidermis.

[0032] An axial connecting screw 231 is positioned above the clamp 23, with its upper end connected to the threaded hole at the bottom of the tension / compression sensor 22, and its lower end fixedly connected to the top center of the first clamping sleeve 232. The clamp 23 has an overall length of not less than 60mm, enabling it to reliably transmit bidirectional tension and compression loads during long-term alternating vibration and pulling processes.

[0033] Example 3: Acoustic Emission Array Positioning Based on Embodiment 1, multiple acoustic emission sensors are arranged in a spatial array at different side walls, heights, and depths of the transparent box 1. For example, multiple mounting holes 11 are provided on the left, right, and rear side walls of the transparent box 1, and the acoustic emission sensors are positioned close to the main root, lateral roots, and root tip regions of the root system.

[0034] The control system 4 has a built-in acoustic emission source positioning module. When frictional slippage occurs at the root-soil interface, root fracture occurs, or soil cracks propagate, the generated acoustic emission waves are received by multiple acoustic emission sensors. The control system 4 uses the time difference of the acoustic emission waves arriving at each sensor, combined with the propagation speed of sound waves in the soil, to invert and locate the acoustic emission source.

[0035] This method can identify the initiation point of local root damage, the root-soil interface slip zone, the fracture zone, and the crack propagation path, thus no longer relying solely on acoustic emission intensity to determine damage, but being able to obtain the spatial location of the damage.

[0036] Example 4: Displacement Field Visual Measurement System A displacement field visual measurement system 8 is installed on the front or outer side of the transparent box 1. The displacement field visual measurement system 8 may include a high-speed camera, an industrial camera, a supplementary light source, and a DIC digital image correlation analysis module.

[0037] Before testing, a speckle pattern can be arranged on the soil surface corresponding to the transparent observation surface of transparent box 1, or the natural texture of soil particles can be used as an image correlation analysis feature. During loading, a high-speed camera or industrial camera continuously acquires images of the soil surface. The DIC digital image correlation analysis module calculates the displacement field, strain field, and crack propagation path of the soil surface from the continuous images.

[0038] The control system 4 synchronizes the image data with the tensile and compressive data, displacement data, and acoustic emission data in time, and can establish a multi-source coupling relationship of "displacement field - acoustic emission source - anchoring force attenuation". For example, when a significant displacement concentration occurs in a certain area, it can be correlated with the acoustic emission source location results to determine whether root-soil interface slippage or root fracture has occurred in that area.

[0039] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A dynamic testing device for root anchorage force based on acoustic emission recognition under controllable vibration conditions, characterized in that: It includes a transparent box (1), a hydraulic longitudinal loading unit (2), an acoustic emission monitoring unit (3), and a control system (4). The transparent box (1) has a hollow square structure with an open top, and its interior is filled with soil for planting the plant (5) to be tested. The side wall of the transparent box (1) is provided with several mounting holes (11). The hydraulic longitudinal loading unit (2) includes a hydraulic servo vibration cylinder (21), a tension and compression sensor (22), and a clamp (23). The hydraulic servo vibration cylinder (21) is located above the transparent box (1). The bottom end of the piston rod of the hydraulic servo vibration cylinder (21) is connected to the tension and compression sensor (22). The tension and compression sensor (22) is connected to the stem of the plant under test (5) through the clamp (23). The acoustic emission monitoring unit (3) includes several acoustic emission sensors buried in the soil through the mounting holes (11); The hydraulic servo vibration cylinder (21), tension and compression sensor (22), and acoustic emission sensor are all electrically connected to the control system (4).

2. The root anchoring force dynamic testing device based on acoustic emission identification under controllable vibration conditions according to claim 1, characterized in that: The hydraulic longitudinal loading unit (2) also includes a base (24) and a gantry bracket (25). The transparent box (1) is fixed to the middle of the upper surface of the base (24). The gantry bracket (25) is an inverted "U" shaped structure composed of two side support columns and a top crossbeam. The bottom of the two side support columns is fixed to the two sides of the upper surface of the base (24). The two ends of the crossbeam are connected to the top of the two side support columns. The cylinder seat of the hydraulic servo vibration cylinder (21) is fixed to the middle of the crossbeam.

3. The root anchoring force dynamic testing device based on acoustic emission recognition under controllable vibration conditions according to claim 2, characterized in that: A hydraulic pump (6) is provided on one side of the gantry support (25). One end of the hydraulic pump (6) is connected to the oil tank, and the other end is connected to one end of the hydraulic hose (7) through a servo valve. The other end of the hydraulic hose (7) is connected to the cylinder of the hydraulic servo vibration cylinder (21). The servo valve is electrically connected to the control system (4).

4. The root anchoring force dynamic testing device based on acoustic emission identification under controllable vibration conditions according to claim 3, characterized in that: The clamp (23) includes an axially connecting screw (231), a first clamping sleeve (232), a second clamping sleeve (233), a silicone pad (234), and a locking bolt (235). The first clamping sleeve (232) and the second clamping sleeve (233) have a semi-circular structure, and the inner walls of both are provided with silicone pads (234). The silicone pads (234) have a semi-cylindrical structure, and their inner sides are provided with grooves for clamping stems. The first clamping sleeve (232) and the second clamping sleeve (233) Ear plates (236) are provided on both sides, and the ear plate holes on the ear plates (236) on both sides are locked by the locking bolts (235) and nuts; an axial connecting screw (231) is provided above the first clamping sleeve (232) and the second clamping sleeve (233), and the external thread of the axial connecting screw (231) is threadedly connected to the threaded hole at the bottom of the tension and pressure sensor (22), and the bottom end of the axial connecting screw (231) is fixedly connected to the middle of the top of the first clamping sleeve (232).

5. The root anchoring force dynamic testing device based on acoustic emission identification under controllable vibration conditions according to claim 4, characterized in that: The transparent box (1) is composed of a transparent plexiglass plate, a transparent tempered glass plate or a transparent acrylic plate spliced ​​with a metal reinforcing frame. The front and at least one side of the transparent box (1) are transparent observation surfaces. The visible light transmittance of the transparent observation surfaces is not less than 90%, and the seams are sealed with silicone sealant or sealing strips.

6. The root anchoring force dynamic testing device based on acoustic emission identification under controllable vibration conditions according to claim 5, characterized in that: A sealing ring is provided at the mounting hole (11), and the housing of the acoustic emission sensor is sealed with the mounting hole (11) by an O-ring. The sensitive surface of the acoustic emission sensor faces the root distribution area of ​​the plant (5) being tested. Multiple acoustic emission sensors are arranged in a spatial array at different heights and different side wall positions of the transparent box (1). The control system (4) has a built-in acoustic emission source positioning module. The acoustic emission source positioning module spatially locates the friction zone, slip zone, fracture zone or root damage initiation zone of the root-soil interface based on the arrival time difference of the acoustic emission signals received by multiple acoustic emission sensors.

7. The root anchoring force dynamic testing device based on acoustic emission identification under controllable vibration conditions according to claim 6, characterized in that: The hydraulic servo vibration cylinder (21) is a double-acting hydraulic servo cylinder with a maximum output force of not less than 10kN, a working frequency of 0.1Hz to 30Hz, and an amplitude of ±0.1mm to ±15mm. It can output sine waves, triangular waves, square waves, swept waves, or random waves superimposed with slope pull-out bias. The tension and pressure sensor (22) is a spoke-type bidirectional force sensor, an S-type bidirectional force sensor, or a column-type bidirectional force sensor with a range of 0 to 10kN and an accuracy of not less than 0.1%. It is used to simultaneously measure the dynamic alternating force and average pull-out force on the stem of the plant (5) being tested.

8. The root anchoring force dynamic testing device based on acoustic emission recognition under controllable vibration conditions according to claim 7, characterized in that: It also includes a displacement field visual measurement system (8), which is set outside the transparent box (1). The displacement field visual measurement system (8) includes at least one of a high-speed camera, an industrial camera, a supplementary light source, and a digital image correlation analysis module, for non-contact measurement of the soil surface displacement field, crack propagation path, and local deformation of the root-soil interface. The control system (4) synchronizes the image data collected by the displacement field visual measurement system (8), the acoustic emission data collected by the acoustic emission monitoring unit (3), and the mechanical data collected by the tensile and compressive sensors (22) in time to establish the correspondence between the displacement field, the acoustic emission source position, and the anchoring force attenuation.

9. A test method for a dynamic testing device for root anchorage force based on acoustic emission identification under controllable vibration conditions as described in claim 8, characterized in that, Includes the following steps: S1. Fill the transparent box (1) with soil and plant the test plant (5) so that the roots of the test plant (5) can grow or be fixed in the soil. S2. Bury multiple acoustic emission sensors in the soil near the roots through the mounting holes (11) and make the acoustic emission sensors tightly coupled to the soil. S3. The stem of the plant under test (5) is clamped by the clamp (23) so that the plant under test (5) is coaxially connected with the hydraulic servo vibration cylinder (21) and the tension and compression sensor (22); S4. By setting the waveform, frequency and amplitude of the longitudinal vibration component and the rising rate of the pull-out component through the control system (4), the hydraulic servo vibration cylinder (21) is controlled to apply a longitudinal vibration load with pull-out bias to the plant under test (5). S5. During the loading process, tensile and compressive signals, displacement signals and acoustic emission signals are collected simultaneously, and the average tensile force component and dynamic force component are separated by filtering method. S6. Identify the root anchorage failure state based on at least one of the following: average tensile peak value, abrupt change in acoustic emission energy, change in acoustic emission event rate, dynamic stiffness decrease rate, and change in root-soil interface displacement field. S7 outputs vibration parameters, pull-out parameters, acoustic emission response, displacement field response, and dynamic attenuation curve of anchoring force.

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