Landslide monitoring device and method based on acoustic emission characteristics of granular material

Abstract

The invention provides a landslide monitoring device and method based on acoustic emission characteristics of granular materials, and relates to the field of geological disaster prevention and control, the landslide monitoring device comprises a waveguide rod, an acoustic emission monitoring unit and an analysis unit, a geological drill hole is divided into at least two hole sections from bottom to top, and each hole section is filled with the granular materials; the diameters and / or materials of the granular materials in different hole sections are different; the acoustic emission monitoring unit can monitor acoustic emission information of the granular material in each hole section, and the acoustic emission information comprises a plurality of acoustic emission characteristic parameters; the acoustic emission information of the granular materials in different hole sections at the same sliding speed is different; the analysis unit is in signal connection with the acoustic emission monitoring unit; and the analysis unit can judge whether landslide deformation is generated or not according to the acoustic emission information, and obtain the type of the granular material in the hole section where the landslide deformation is generated and / or the depth of the slip surface. According to the invention, low-cost and continuous monitoring of deep displacement can be realized, and meanwhile, the depth of a slip plane when a landslide occurs can be judged.

Description

Technical Field

[0001] The present invention relates to the technical field of geological disaster prevention and control, and particularly to a landslide monitoring device and method based on the acoustic emission characteristics of granular materials. Background Art

[0002] Landslides are a common geological disaster. China has a complex and diverse terrain and landforms, with many mountainous areas and hills. Affected by the monsoon climate, the annual precipitation is concentrated, resulting in frequent landslide disasters, causing huge economic losses and seriously threatening the safety of mountain residents. Landslide monitoring and early warning can effectively reduce disaster losses, ensure the safety of people's lives and property, and provide a scientific decision-making basis for geological disaster prevention and control by identifying potential hazards in advance and issuing early warning information.

[0003] Currently, the commonly used landslide monitoring methods mainly include surface displacement monitoring means such as total station, Global Navigation Satellite System (GNSS), Interferometric Synthetic Aperture Radar (InSAR), and Unmanned Aerial Vehicle Light Detection and Ranging (LiDAR), and underground deformation monitoring means such as inclinometers and fiber optic sensors. Among them, the total station mainly relies on manual monitoring and cannot achieve real-time continuous dynamic monitoring and early warning; surface displacement monitoring means such as GNSS mainly monitor the displacement and deformation field of the slope surface and cannot monitor the internal deformation of the slope and the potential slip surface of the slope, and cannot capture the internal deformation and failure conditions of the slope before the landslide occurs, and there is a lag in the monitoring results; although underground deformation monitoring means such as automatic inclinometers and fiber optic sensors can continuously monitor the deep deformation, they are expensive and the monitoring cost is high. Summary of the Invention

[0004] The purpose of the present invention is to provide a landslide monitoring device and method based on the acoustic emission characteristics of granular materials to solve the problems existing in the above-mentioned prior art, which can achieve low-cost and continuous monitoring of deep displacement, and can also judge the depth of the slip surface when a landslide occurs.

[0005] To achieve the above purpose, the present invention provides the following solutions:

[0006] The present invention provides a landslide monitoring device based on the acoustic emission characteristics of granular materials, including a waveguide rod, an acoustic emission monitoring unit, and an analysis unit, wherein:

[0007] The waveguide rod is used to be arranged in a geological borehole drilled on a slope to be monitored. The geological borehole is divided into at least two hole sections from bottom to top. Granular materials are filled between the outer sidewall of the waveguide rod and the inner sidewall of each hole section, and the particle size and / or material of the granular materials in different hole sections are different;

[0008] The acoustic emission monitoring unit is connected to the waveguide rod. The acoustic emission monitoring unit can monitor the acoustic emission information of the granular material in each of the hole sections, and the acoustic emission information includes at least three acoustic emission characteristic parameters; the acoustic emission information of the granular material in different hole sections is not exactly the same under the same shear speed;

[0009] The analysis unit is signal-connected to the acoustic emission monitoring unit; the analysis unit can judge whether landslide deformation occurs according to the acoustic emission information detected by the acoustic emission monitoring unit, and can obtain the type of the granular material and / or the depth information of the slip surface in the hole section where landslide deformation occurs.

[0010] Preferably, the acoustic emission information includes ring count, acoustic emission energy, and main frequency of the acoustic emission signal.

[0011] Preferably, the acoustic emission information further includes acoustic emission event rate.

[0012] Preferably, the particle sizes and materials of the granular materials in different hole sections are different.

[0013] Preferably, the geological borehole is divided into three hole sections from bottom to top, and granular material one, granular material two, and granular material three are filled in the three hole sections from bottom to top respectively. The particle sizes of the granular material one, the granular material two, and the granular material three increase in sequence. The granular material one is quartz sand, the granular material two is glass beads, and the granular material three is steel balls.

[0014] Preferably, it further includes an early warning unit. The acoustic emission information of the granular material in the same hole section is not exactly the same under different shear speeds. The analysis unit can obtain the slip speed range value and / or early warning level of the landslide according to the acoustic emission information detected by the acoustic emission monitoring unit, and the early warning unit is signal-connected to the analysis unit.

[0015] The present invention also provides a landslide monitoring method based on the landslide monitoring device based on the acoustic emission characteristics of granular materials, including the following steps:

[0016] S1. Drill a hole at the position to be monitored on the slope to be monitored, set the waveguide rod in the geological borehole, and fill the granular material into each of the hole sections of the geological borehole. The particle sizes and / or materials of the granular materials in different hole sections are different;

[0017] S2. Monitor the acoustic emission information of the granular material in each of the hole sections through the acoustic emission monitoring unit;

[0018] S3. The analysis unit determines whether landslide deformation occurs according to the acoustic emission information sent by the acoustic emission monitoring unit, and obtains the type of the granular material and / or the depth information of the slip surface in the hole section where landslide deformation occurs.

[0019] Preferably, it further includes an early warning unit, and the early warning unit is signal-connected to the analysis unit; the acoustic emission information of the granular material in the same hole section at different shear rates is not completely the same;

[0020] S3 further includes: when landslide deformation occurs on the hole wall of the geological borehole, the analysis unit obtains the range value of the landslide slip speed and determines the alarm level according to the range value of the slip speed, and the early warning unit gives a landslide early warning of the corresponding level.

[0021] Preferably, S3 includes:

[0022] In the analysis unit, a mapping relationship between the acoustic emission information of each granular material at different shear rates and the type of granular material is preset. The analysis unit obtains the type of the granular material and / or the depth information of the slip surface in the hole section where landslide deformation occurs through the acoustic emission information detected by the acoustic emission monitoring unit and the mapping relationship, and the analysis unit obtains the alarm level corresponding to the landslide deformation through the acoustic emission information detected by the acoustic emission monitoring unit and the mapping relationship.

[0023] Preferably, the method for obtaining the mapping relationship includes: obtaining the simulated values of the acoustic emission information of each granular material at different shear rates through experimental simulation, constructing a deep learning classification model based on a fully connected neural network according to the corresponding relationship between the acoustic emission simulation information of each granular material at different shear rates and the type of granular material, using multiple acoustic emission characteristic parameters as the input layer, extracting feature representations through multi-layer non-linear transformation, and finally outputting the type of granular material and the warning level; implementing the trained deep learning classification model through code, integrating it into a single-chip microcomputer system with edge computing function, and presetting it into the analysis unit.

[0024] The present invention has achieved the following technical effects compared with the prior art:

[0025] The present invention provides a landslide monitoring device and method based on the acoustic emission characteristics of granular materials, including a waveguide rod, an acoustic emission monitoring unit, and an analysis unit. The waveguide rod is configured to be disposed in a geological borehole drilled on a slope to be monitored. The geological borehole is divided into at least two hole sections from bottom to top. Granular materials are filled between the outer sidewall of the waveguide rod and the inner sidewall of each hole section, and the particle size and / or material of the granular materials in different hole sections are different. The acoustic emission monitoring unit is connected to the waveguide rod, and the acoustic emission monitoring unit can monitor the acoustic emission information of the granular materials in each hole section. The acoustic emission information includes at least three acoustic emission characteristic parameters. The acoustic emission information of the granular materials in different hole sections is not completely the same under the same shear rate. The analysis unit is signal-connected to the acoustic emission monitoring unit. The analysis unit can determine whether landslide deformation occurs according to the acoustic emission information detected by the acoustic emission monitoring unit, and can obtain the type of the granular materials in the hole section where the landslide deformation occurs and / or the depth information of the slip surface.

[0026] In this embodiment, the acoustic emission monitoring unit monitors multiple acoustic emission characteristic parameters of the granular materials at each hole section during landslide deformation. When landslide deformation occurs, since the acoustic emission information of the granular materials in different hole sections is different, the analysis unit can obtain the type of the granular materials that generate the acoustic emission information according to the received acoustic emission information. The depth information of the landslide deformation can be obtained through the type of the granular materials at the landslide deformation position, realizing low-cost and continuous monitoring of deep displacement, and at the same time, the depth of the slip surface when the landslide occurs can also be judged. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 It is a schematic structural diagram of the landslide monitoring device based on the acoustic emission characteristics of granular materials provided in Embodiment 1;

[0029] Figure 2 It is a cross-sectional view of the landslide monitoring device based on the acoustic emission characteristics of granular materials provided in Embodiment 1;

[0030] Figure 3 It is a working flow chart of the landslide monitoring device based on the acoustic emission characteristics of granular materials provided in Embodiment 1;

[0031] Figure 4 It is a flow chart of landslide monitoring using the deep learning classification model based on the fully connected neural network provided in Embodiment 2;

[0032] In the figure: 100, landslide monitoring device based on the acoustic emission characteristics of granular materials; 1, waveguide rod; 2, acoustic emission monitoring unit; 3, analysis unit; 4, geological borehole; 5, granular material one; 6, granular material two; 7, granular material three; 8, sealing component; 9, centralizer; 10, storage battery; 11, solar panel; 12, protection device; 13, signal sending unit; 14, slip surface; 15, slope to be monitored. Specific embodiments

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] The purpose of the present invention is to provide a landslide monitoring device and method based on the acoustic emission characteristics of granular materials to solve the problems existing in the above-mentioned prior art, which can achieve low-cost and continuous monitoring of deep displacement, and can also judge the depth of the slip surface when a landslide occurs.

[0035] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Embodiment 1

[0037] As Figures 1 to 4 shown, this embodiment provides a landslide monitoring device 100 based on the acoustic emission characteristics of granular materials, including a waveguide rod 1, an acoustic emission monitoring unit 2, and an analysis unit 3, wherein:

[0038] The waveguide rod 1 is used to be arranged in the geological borehole 4 drilled on the slope 15 to be monitored. The geological borehole 4 is divided into at least two hole sections from bottom to top. Granular materials are filled between the outer side wall of the waveguide rod 1 and the inner side wall of each hole section, and the particle sizes and / or materials of the granular materials in different hole sections are different;

[0039] The acoustic emission monitoring unit 2 is connected to the waveguide rod 1. The acoustic emission monitoring unit 2 can monitor the acoustic emission information of the granular materials in each hole section, and the acoustic emission information includes at least three acoustic emission characteristic parameters; the acoustic emission information of the granular materials in different hole sections is not exactly the same under the same slip speed;

[0040] The analysis unit 3 is signal-connected to the acoustic emission monitoring unit 2; the analysis unit 3 can judge whether landslide deformation occurs according to the acoustic emission information detected by the acoustic emission monitoring unit 2, and can obtain the type of the granular materials in the hole section where landslide deformation occurs and / or the depth information of the slip surface 14.

[0041] In this embodiment, the acoustic emission monitoring unit 2 monitors multiple acoustic emission characteristic parameters of the granular material at each hole section during landslide deformation. When landslide deformation occurs, since the acoustic emission information of the granular material in different hole sections is different, the analysis unit 3 can obtain the type of the granular material that generates the acoustic emission information according to the received acoustic emission information. The depth information of the landslide deformation can be obtained through the type of the granular material at the landslide deformation position, realizing low-cost and continuous monitoring of deep displacement. At the same time, the depth of the slip surface 14 during landslide occurrence can also be judged.

[0042] In some embodiments, the acoustic emission information includes ring count, acoustic emission energy, and main frequency of the acoustic emission signal.

[0043] In some embodiments, the acoustic emission information further includes acoustic emission event rate.

[0044] In some embodiments, the particle sizes and materials of the granular materials in different hole sections are different.

[0045] In some embodiments, the geological borehole 4 is divided into three hole sections from bottom to top. Granular material one 5, granular material two 6, and granular material three 7 are filled in the three hole sections from bottom to top respectively. The particle sizes of granular material one 5, granular material two 6, and granular material three 7 increase in sequence. Granular material one 5 is quartz sand, granular material two 6 is glass beads, and granular material three 7 is steel beads. The relationship between the acoustic emission characteristic parameters of each granular material in this embodiment and the shear rate is as follows: First, the main frequency of the acoustic emission signal: With the increase of the shear rate, the main frequency of the acoustic emission signal of quartz sand first rises and then tends to be stable. Specifically, when the shear rate < 1 mm / h, the main frequency of the acoustic emission signal is relatively high (about 100 - 200 kHz). When the shear rate > 5 mm / h, the main frequency of the acoustic emission signal decreases slightly. With the increase of the shear rate, the main frequency of the acoustic emission signal of glass beads gradually decreases. Steel beads are not sensitive to the shear rate. When the shear rate of steel beads increases, it remains at a low frequency (about 50 - 100 kHz). Second, the acoustic emission energy: With the increase of the shear rate, the acoustic emission energy of quartz sand increases linearly. Specifically, during low-speed shearing, such as when the shear rate is about 0.1 mm / h, the acoustic emission energy is about 10 - 50 mV2·s. During high-speed shearing, such as when the shear rate is about 10 mm / h, the acoustic emission energy can reach 100 - 300 mV2·s. With the increase of the shear rate, the growth rate of the acoustic emission energy of glass beads is first fast and then slow. Specifically, during low-speed shearing, the acoustic emission energy of glass beads is 50 - 150 mV2. During high-speed shearing, the increase amplitude of the acoustic emission energy of glass beads slows down. With the increase of the shear rate, the acoustic emission energy of steel beads has an exponential relationship with the shear rate. Specifically, during low-speed shearing, such as when the shear rate is about 0.1 mm / h, the acoustic emission energy is about 200 - 500 mV2·s. During high-speed shearing, such as when the shear rate is about 10 mm / h, the acoustic emission energy can reach 1000 - 3000 mV2·s. Third, the ring count: With the increase of the shear rate, the ring count of quartz sand increases significantly. Specifically, during low-speed shearing, the ring count is about 500 - 1000 times / 10 s. During high-speed shearing, the ring count can reach 5000 - 10000 times / 10 s. With the increase of the shear rate, the growth rate of the ring count of glass beads is relatively gentle. Specifically, during low-speed shearing, the ring count is about 300 - 800 times / 10 s. During high-speed shearing, the ring count can reach 1000 - 2000 times / 10 s. With the increase of the shear rate, the ring count of steel beads changes little at low shear rates and surges at high shear rates. Specifically, during low-speed shearing, the ring count is about 100 - 300 times / 10 s. During high-speed shearing, the ring count suddenly spikes (such as 5000 times / 10 s) and then drops back.Fourth, acoustic emission event rate: As the shear rate increases, the acoustic emission event rate of quartz sand is positively correlated with the shear rate. Specifically, at low-speed shear, such as when the shear rate is 0.1 mm / h, the acoustic emission event rate is 50 - 100 Hz; at high-speed shear, such as when the shear rate is 10 mm / h, the acoustic emission event rate is 500 - 1000 Hz. As the shear rate increases, the acoustic emission event rate of glass beads first increases and then decreases. Specifically, at low-speed shear, the acoustic emission event rate is 30 - 80 Hz; at high-speed shear, the acoustic emission event rate is 100 - 200 Hz. As the shear rate increases, the acoustic emission event rate of steel beads is positively correlated with the shear rate. Specifically, at low-speed shear, the acoustic emission event rate is 10 - 30 Hz; at high-speed shear, the acoustic emission event rate is 100 - 500 Hz. In this embodiment, the relationship curves of the ring count and the shear rate of the three types of particulate materials are different, the relationship curves of the acoustic emission energy and the shear rate of the three types of particulate materials are different, the relationship curves of the main frequency of the acoustic emission signal and the shear rate of the three types of particulate materials are different, and the relationship curves of the acoustic emission event rate and the shear rate of the three types of particulate materials are different, so that the depth information generated by landslide deformation can be better obtained.

[0046] In some embodiments, a couplant is filled in the gap between the acoustic emission monitoring unit 2 and the waveguide rod 1. The couplant is preferably vaseline. The couplant can reduce the influence of the trace air in the gap between the acoustic emission monitoring unit 2 and the waveguide rod 1 on the penetration of sound waves; it can reduce the acoustic impedance difference between the contact surfaces of the waveguide rod 1 and the acoustic emission monitoring unit 2, that is, the reflection loss of energy between the contact surfaces will be reduced.

[0047] In some embodiments, it further includes a sealing component 8 and at least two centralizers 9. The sealing component 8 is arranged in the geological borehole 4 above the particulate material. The sealing component 8 can seal the gap between the waveguide rod 1 and the geological borehole 4; each centralizer 9 is connected to the waveguide rod 1, and the outer sidewall of each centralizer 9 can contact the inner sidewall of the geological borehole 4. The centralizer 9 can make the center line of the waveguide rod 1 coincide with the axis of the geological borehole 4. The centralizer 9 is used to center the waveguide rod 1 in the geological borehole 4 to improve the accuracy and reliability of the measurement signal.

[0048] In some embodiments, it further includes a solar power supply device, and the solar power supply device can be electrically connected to the analysis unit 3 and the acoustic emission monitoring unit 2. The solar power supply device includes a storage battery 10 and a solar panel 11. The storage battery 10 is connected to the solar panel 11 and electrical components such as the analysis unit 3 and the acoustic emission monitoring unit 2 to supply power to the electrical components of the landslide monitoring device 100 based on the acoustic emission characteristics of particulate materials. After the landslide monitoring device 100 based on the acoustic emission characteristics of particulate materials in this embodiment is installed, the solar power supply device can supply continuous power to it, without the need to replace the battery, and the monitoring has good continuity and strong applicability.

[0049] In some embodiments, it further includes an early warning unit. The acoustic emission information of granular materials in the same hole section is not completely the same under different shear speeds. The analysis unit 3 can obtain the slip speed range value and / or early warning level of the landslide according to the acoustic emission information detected by the acoustic emission monitoring unit 2. The early warning unit is signal-connected to the analysis unit 3. The analysis unit 3 can perform hierarchical alarm through the early warning unit when the landslide deforms. The analysis unit 3 can also be connected to the server and issue an early warning to the mobile phone through the server. As a preferred implementation manner, the early warning unit is a mobile transmission unit.

[0050] As a preferred implementation manner, the sealing member 8 is a bentonite grouting plug. After filling the granular materials, bentonite is filled in the geological borehole 4, and then water is added. The bentonite expands when it meets water to form a bentonite grouting plug, which can play a good sealing role, reduce the interference of external noise, and improve the detection accuracy.

[0051] As a preferred implementation manner, it further includes a signal acquisition unit and a signal transmission unit 13. Both the signal acquisition unit and the signal transmission unit 13 are signal-connected to the analysis unit 3; the signal transmission unit 13 can be connected to external components such as the server and the mobile phone. The power supply is electrically connected to the signal acquisition unit, the signal transmission unit 13, and the analysis unit 3 and supplies power to the signal acquisition unit, the signal transmission unit 13, and the analysis unit 3. Among them, the analysis unit 3 relies on a single-chip microcomputer to calculate and analyze digital signals. The signal acquisition unit internally integrates a band-pass filter, a preamplifier, and an A / D conversion circuit. The band-pass filter is mainly used to eliminate noise and limit the working frequency range of the detection system; since the voltage output by the sensor is often very low, even as low as microvolts, for such weak signals, the signal-to-noise ratio will decrease during long-distance transmission, and the role of the preamplifier is to improve the signal-to-noise ratio, with the functions of high gain and low noise; the A / D conversion circuit is a circuit constructed by a single-chip microcomputer with an A / D converter, which can reduce the circuit scale and has low power consumption, and can convert the voltage signal into a digital signal. The signal transmission unit 13 is a wireless transmission unit, which can be a GPRS wireless communication module. This module can be connected to the Internet through a serial port and can transmit data with each other through GPRS and the cellular 5G network. As a more preferred implementation manner, when the critical landslide speed exceeds 20 mm / h, the signal transmission unit 13 will send a landslide early warning signal to the mobile phone, and at the same time send the depth information of the slip surface 14 at the geological borehole 4 to remind relevant personnel to take corresponding measures. The signal acquisition unit and the analysis unit 3 of the landslide monitoring device 100 based on the acoustic emission characteristics of granular materials in this embodiment are both constructed by single-chip microcomputers. Compared with traditional landslide monitoring devices 100 based on the acoustic emission characteristics of granular materials such as total stations, inclinometers, and array displacement meters, the cost is lower, the circuit scale is small, the power consumption cost is low, and it can calculate and analyze the position of the slip surface 14 and the landslide speed more efficiently, with high cost performance.

[0052] As a preferred embodiment, the acoustic emission monitoring unit 2 is an acoustic emission sensor. More preferably, a broadband acoustic emission sensor of model UT1000 is adopted. The broadband acoustic emission sensor includes structures such as a contact surface, piezoelectric ceramics, terminal blocks, damping materials, etc. Damping materials are pasted on the ceramics to suppress resonance. The broadband acoustic emission sensor can capture relatively real signals, making its signals richer and more comprehensive. The acoustic emission monitoring unit 2 is fixed on the active waveguide rod 1 and is used to convert the received mechanical signals into electrical signals.

[0053] As a preferred embodiment, it further includes a protection device 12. The upper end of the waveguide rod 1 extends out of the geological borehole 4. A protection device 12 is arranged outside the waveguide rod 1. The acoustic emission monitoring unit 2, the analysis unit 3, the signal acquisition unit, the power supply, etc. are all arranged inside the protection device 12. The protection device 12 has a closed space and can protect the acoustic emission monitoring unit 2, the analysis unit 3, and the signal acquisition unit.

[0054] As a preferred embodiment, the waveguide rod 1 is an active waveguide rod 1 and is made of a metal material. More preferably, the material of the waveguide rod 1 is 10# steel. The diameter of the waveguide rod 1 is 5 - 40 mm. At this time, the propagation of the acoustic emission signal in the waveguide rod 1 is relatively stable. More preferably, the diameter of the waveguide rod 1 is 20 mm, which can better obtain the signal amplitude envelope. The length of the waveguide rod 1 is determined according to the depth of the slip surface 14 of the slope 15 to be monitored, ensuring that the waveguide rod 1 penetrates through the slip surface 14 and is about 0.5 m above the ground surface of the slope 15 to be monitored, so as to facilitate the installation of the protection device 12.

[0055] As a preferred embodiment, there are two centralizers 9, which are respectively fixed at the top and bottom of the waveguide rod 1. The length of each hole section is 5 m, that is, the filling thickness of the granular material in each hole section is 5 m.

[0056] Example 2

[0057] This embodiment provides a landslide monitoring method for the landslide monitoring device 100 based on the acoustic emission characteristics of granular materials according to Embodiment 1, including the following steps:

[0058] S1. Drill a hole at the position to be monitored on the slope 15 to be monitored, place the waveguide rod 1 in the geological borehole 4, and fill granular materials into each hole section of the geological borehole 4. The particle sizes and / or materials of the granular materials in different hole sections are different;

[0059] S2. Monitor the acoustic emission information of the granular materials in each hole section through the acoustic emission monitoring unit 2;

[0060] S3. The analysis unit 3 determines whether landslide deformation occurs based on the acoustic emission information sent by the acoustic emission monitoring unit 2, and obtains the type of granular material and / or the depth information of the slip surface 14 within the hole section where the landslide deformation occurs.

[0061] In this embodiment, the acoustic emission monitoring unit 2 monitors multiple acoustic emission characteristic parameters of the granular materials at each hole section. When landslide deformation occurs on the side wall of a certain hole section, acoustic emission phenomena occur in the granular materials within this hole section, and the acoustic emission monitoring unit 2 obtains the acoustic emission information of the granular materials within this hole section. The analysis unit 3 obtains the depth information of the landslide deformation through this acoustic emission information, realizing low-cost and continuous monitoring of deep displacement. At the same time, it can also judge the depth of the slip surface 14 when the landslide occurs.

[0062] In some embodiments, S3 further includes: when landslide deformation occurs on the hole wall of the geological borehole 4, the analysis unit 3 obtains the range value of the slip speed of the landslide and judges the alarm level according to the range value of the slip speed, and the warning unit issues a landslide warning of the corresponding level.

[0063] In some embodiments, S3 includes: a mapping relationship between the acoustic emission information of each granular material at different shear rates and the type of granular material is preset in the analysis unit 3. The analysis unit 3 can obtain the type of granular material and / or the depth information of the slip surface 14 within the hole section where the landslide deformation occurs through the acoustic emission information detected by the acoustic emission monitoring unit 2 and the mapping relationship. The analysis unit 3 obtains the alarm level corresponding to the landslide deformation through the acoustic emission information detected by the acoustic emission monitoring unit 2 and the mapping relationship.

[0064] In some embodiments, the method for obtaining the mapping relationship includes: obtaining the simulated values of the acoustic emission information of each granular material at different shear rates through experimental simulation, and obtaining the mapping relationship through the simulated values of the acoustic emission information of each granular material at different shear rates.

[0065] In some embodiments, the method for obtaining the mapping relationship includes: obtaining the simulated values of the acoustic emission information of each granular material at different shear rates through experimental simulation, and obtaining the mapping relationship through the simulated values of the acoustic emission information of each granular material at different shear rates. The specific implementation method of the mapping relationship is to construct a deep learning classification model based on a fully connected neural network according to the corresponding relationship between the acoustic emission simulation information of each granular material at different shear rates and the type of granular material. Using the acoustic emission characteristic parameters (ring count, acoustic emission energy, main frequency of acoustic emission signal, acoustic emission event rate) as the input layer, extracting feature representations through multi-layer nonlinear transformations, and finally outputting the type of granular material and the warning level. Then, the trained deep learning classification model is implemented through code and integrated into a single-chip microcomputer system with edge computing capabilities, and is preset in the analysis unit 3.

[0066] As a preferred embodiment, a large direct shear apparatus is used to conduct shear tests on different types of granular materials at different shear rates to simulate landslide scenarios at different sliding speeds of the slope, and the acoustic emission characteristic data (ring count, acoustic emission energy, main frequency of acoustic emission signal, and acoustic emission event rate) of each granular material at different shear rates is obtained. The warning levels can be set to four levels (L1, L2, L3, L4).

[0067] As a preferred embodiment, when conducting landslide monitoring, the acoustic emission monitoring unit 2 is used to continuously and real-time monitor the acoustic emission signals in the geological borehole 4. The acoustic emission signals are converted into digital signals through analog-to-digital conversion, and then the analysis unit 3 calculates the type of granular material corresponding to the acoustic emission signals and the warning level. If the landslide risk level changes, a warning signal corresponding to the risk level is sent through the warning unit, and at the same time, the depth information of the slip surface 14 located according to the type of granular material is sent. For example, when there are three types of granular materials, they respectively correspond to deep-seated landslides, mid-level landslides, and shallow landslides.

[0068] In some embodiments, the position to be monitored is the position of the potential slip surface 14 of the slope 15 to be monitored; the depth of the geological borehole 4 is greater than the depth of the potential slip surface 14 at the location where the geological borehole 4 is located; S1 further includes: extending the lower end of the waveguide rod 1 below the potential slip surface 14 at the location where the geological borehole 4 is located, so as to accurately monitor the activity of the slip surface 14.

[0069] As a preferred embodiment, S1 further includes: selecting a sensitive slope. Usually, through comprehensive analysis of regional geological conditions, historical landslide events, topography and meteorological conditions, etc., geological and geomorphic surveys are carried out through remote sensing technologies such as terrestrial laser scanning (TLS) and infrared thermal imaging (IRT), and exploration and surveying technologies are used to determine the key joints of the slope rock mass and the position of the potential slip surface 14, and determine the position of the geological borehole 4 for installing the landslide monitoring device 100 based on the acoustic emission characteristics of granular materials on site.

[0070] As a preferred embodiment, S1 further includes: before installing the landslide monitoring device 100 based on the acoustic emission characteristics of granular materials, flushing the hole wall of the geological borehole 4; then, installing the waveguide rod 1 in the geological borehole 4, and the waveguide rod 1 needs to penetrate through the potential slip surface 14 formed under the slope; filling different types of granular materials around the waveguide rod 1 in ascending order of particle size from bottom to top; filling bentonite at the orifice of the waveguide rod 1 and making it expand to form a bentonite grouting plug; installing the protection device 12; installing an acoustic emission monitoring device, a data acquisition and analysis system (signal acquisition unit, analysis unit 3, signal sending unit 13, etc.) and a power supply system in the protection device 12;

[0071] This embodiment can monitor the stability of the slope 15 to be monitored and determine the slip position of the slope 15 to be monitored based on the acoustic emission signal characteristics generated by different types of granular materials during the deformation process. Specifically, during the slope instability process, different types of granular materials filled around the waveguide rod 1 are sheared under the influence of the surrounding rock and soil mass. During the shearing process, the acoustic emission characteristic parameter values are different for different types and different shear speeds. The acoustic emission sensor in the protection device 12 located at the top of the waveguide rod 1 converts the detected acoustic emission characteristic signal into a voltage signal, and then the signal acquisition unit filters and amplifies the voltage signal and sends it to the A / D conversion circuit; the A / D conversion circuit converts the voltage signal into a digital signal and sends it to the analysis unit 3. The analysis unit 3 relies on the single-chip microcomputer to calculate and analyze the digital signal to locate the depth range of the slip surface 14 at the geological borehole 4. When the landslide speed exceeds the warning threshold, the signal sending unit 13 will send a landslide warning signal to the mobile phone and simultaneously send the depth information of the slip surface 14 at the geological borehole 4 to remind relevant personnel to take corresponding measures.

[0072] Specific examples are used in the present invention to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, based on the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A landslide monitoring device based on the acoustic emission characteristics of granular materials, characterized in that: It includes a waveguide rod, an acoustic emission monitoring unit and an analysis unit, wherein: The waveguide rod is used to be arranged in a geological borehole drilled on the slope to be monitored. The geological borehole is divided into at least two hole sections from bottom to top. Granular materials are filled between the outer side wall of the waveguide rod and the inner side wall of each hole section. The particle sizes and / or materials of the granular materials in different hole sections are different; The acoustic emission monitoring unit is connected to the waveguide rod. The acoustic emission monitoring unit can monitor the acoustic emission information of the granular materials in each hole section. The acoustic emission information includes at least three acoustic emission characteristic parameters; the acoustic emission information of the granular materials in different hole sections is not completely the same under the same shear speed; The analysis unit is signal-connected to the acoustic emission monitoring unit; the analysis unit can judge whether landslide deformation occurs according to the acoustic emission information detected by the acoustic emission monitoring unit, and can obtain the type of the granular materials in the hole section where landslide deformation occurs and / or the depth information of the slip surface.

2. The landslide monitoring device based on the acoustic emission characteristics of granular materials according to claim 1, wherein: The acoustic emission information includes ring count, acoustic emission energy and main frequency of acoustic emission signal.

3. The landslide monitoring device based on the acoustic emission characteristics of granular materials according to claim 2, characterized in that: The acoustic emission information further includes acoustic emission event rate.

4. The landslide monitoring device based on the acoustic emission characteristics of granular materials according to claim 1, characterized in that: The particle sizes and materials of the granular materials in different hole sections are all different.

5. The landslide monitoring device based on the acoustic emission characteristics of granular materials according to claim 4, characterized in that: The geological borehole is divided into three hole sections from bottom to top. Granular material one, granular material two and granular material three are respectively filled in the three hole sections from bottom to top. The particle sizes of granular material one, granular material two and granular material three increase in sequence. Granular material one is quartz sand, granular material two is glass beads, and granular material three is steel balls.

6. The landslide monitoring device based on the acoustic emission characteristics of granular materials according to claim 1, characterized in that: It further includes a warning unit. The acoustic emission information of the granular materials in the same hole section is not completely the same under different shear speeds. The analysis unit can obtain the slip speed range value and / or warning level of the landslide according to the acoustic emission information detected by the acoustic emission monitoring unit. The warning unit is signal-connected to the analysis unit.

7. A landslide monitoring method for a landslide monitoring device based on the acoustic emission characteristics of granular materials according to any one of claims 1 to 6, characterized in that: It includes the following steps: S1. Drill a hole at the position to be monitored on the slope to be monitored, arrange the waveguide rod in the geological borehole, and fill the granular materials into each hole section of the geological borehole. The particle sizes and / or materials of the granular materials in different hole sections are different; S2. Monitor the acoustic emission information of the granular materials in each hole section through the acoustic emission monitoring unit; S3. The analysis unit judges whether landslide deformation occurs according to the acoustic emission information sent by the acoustic emission monitoring unit, and obtains the type of the granular materials in the hole section where landslide deformation occurs and / or the depth information of the slip surface.

8. The landslide monitoring method according to claim 7, wherein: It further includes a warning unit. The warning unit is signal-connected to the analysis unit; the acoustic emission information of the granular materials in the same hole section is not completely the same under different shear speeds; S3 further includes: when landslide deformation occurs on the hole wall of the geological borehole, obtain the range value of the slip speed of the landslide through the analysis unit and judge the alarm level according to the range value of the slip speed, and the warning unit conducts landslide warning of the corresponding level.

9. The landslide monitoring method according to claim 8, wherein: S3 further includes: In the analysis unit, a mapping relationship between the acoustic emission information of each type of granular material at different shear rates and the type of granular material is preset. The analysis unit obtains the type of the granular material and / or the depth information of the slip surface in the hole section where landslide deformation occurs through the acoustic emission information detected by the acoustic emission monitoring unit and the mapping relationship. The analysis unit obtains the alarm level corresponding to the landslide deformation through the acoustic emission information detected by the acoustic emission monitoring unit and the mapping relationship.

10. The landslide monitoring method according to claim 9, wherein: The method for obtaining the mapping relationship includes: obtaining the simulated values of the acoustic emission information of each type of granular material at different shear rates through experimental simulation, constructing a deep learning classification model based on a fully connected neural network according to the correspondence between the acoustic emission simulation information of each type of granular material at different shear rates and the type of granular material, using multiple acoustic emission characteristic parameters as the input layer, extracting feature representations through multi-layer non-linear transformation, and finally outputting the type of granular material and the warning level; implementing the trained deep learning classification model through code, integrating it into a single-chip microcomputer system with edge computing capabilities, and presetting it in the analysis unit.

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