A system and method for monitoring geological disasters of rock collapse on mountain slopes

Abstract

The present invention discloses a system and method for monitoring geological disasters of rock collapse on mountain slopes, which relate to the technical field of geological disaster monitoring. The monitoring system realizes geological disaster monitoring of rock collapse on bedrock based on the vibration signal on the bedrock picked up by a vibration sensor. In this system, the vibration sensor is fixed to the bedrock by an anchor rod installed in an anchor hole. The signal pickup surface of the vibration sensor is in contact with the surface of the bedrock, and a coupling agent layer is provided between the signal pickup surface and the surface. On the bedrock, a plurality of drainage holes are provided, which are located outside the signal pickup surface and surround the signal pickup surface. The monitoring method is implemented based on the monitoring system. This solution realizes geological disaster monitoring based on vibration signals, which can effectively improve the reliability of vibration signal pickup.

Description

Technical Field

[0001] The present invention relates to the technical field of geological disaster monitoring, and in particular to a system and method for monitoring geological disasters such as rock collapse on slopes in mountainous areas. Background Art

[0002] For the monitoring and prevention of geological disasters, the application of vibration sensors in the monitoring of rockfall on mountain slopes is crucial. This type of sensor and the monitoring network formed can timely capture the vibration signals generated by the impact and rolling of falling rocks. By processing the vibration signals and based on the processing results, valuable time can be effectively gained for early warning and emergency response.

[0003] In existing applications, sensors used to monitor rockfall and collapse hazards on mountain slopes typically require excellent low-frequency performance. Commonly used sensors include accelerometers, seismic wave detectors, and geophones. Specific installation locations are based on geological survey results. For example, based on on-site rockfall track marks, rockfall accumulation area distribution, and the distribution of dangerous rock on the mountain slope, the rockfall's location, main path, and accumulation location are identified. Sensors are primarily installed below the rockfall location and spaced along the main path to capture rock breakaway signals as early as possible and reliably pick up continuous impact signals during the rolling process. The specific installation location should also be prioritized in locations with exposed rock mass, away from weathered layers, and protected from natural interference (such as rainfall) and human interference (such as traffic and other human activities).

[0004] Regarding the specific implementation method, such as the technical solution provided by patent application number CN202411079696.1, an anchor-type fixed vibration sensor is used to form a dot matrix network, and sensors are deployed at key positions in potential rockfall areas, specifically for sensing vibration signals when rockfall occurs. Regarding the specific fixing method of the vibration sensor on the rock mass, such as the technical solution provided by patent application number CN201710302713.7, a sensor fastening device is set on the mounting rod to complete the installation of the sensor at the end of the mounting rod.

[0005] Vibration signal detection has significant advantages in rock collapse geological disasters, including but not limited to: by picking up vibration signals, geological disaster signals can be captured in a premonitory and highly sensitive manner before the disaster can be observed by the naked eye; based on the fast propagation characteristics of vibration signals, geological disaster signals can be obtained in a timely manner; a single monitoring point has a wide coverage range, which can simultaneously cover the surface and deep positions of the rock mass, and realize the location of the occurrence; after installation, it is not easily affected by external environmental interference, and after a one-time installation, it is suitable for long-term and effective monitoring of areas that are difficult for humans to enter. Therefore, further optimizing the geological disaster monitoring method based on vibration signal detection has positive significance for reducing the impact of geological disasters on humans and protecting the ecological environment. Summary of the Invention

[0006] In response to the above-mentioned problem of optimizing the geological disaster monitoring method based on vibration signal detection, the present invention provides a mountain slope rock collapse geological disaster monitoring system and method. This solution realizes geological disaster monitoring based on vibration signals and can effectively improve the reliability of vibration signal pickup.

[0007] In response to the above problems, the present invention provides a system and method for monitoring geological disasters of rock collapse on mountain slopes, which solve the problems through the following technical points: a system for monitoring geological disasters of rock collapse on mountain slopes, which monitors geological disasters of rock collapse on bedrock based on vibration signals on bedrock picked up by a vibration sensor. In this system, the vibration sensor is fixed to the bedrock by an anchor rod installed in an anchor hole, and the signal pickup surface of the vibration sensor is in contact with the surface of the bedrock, with a coupling agent layer provided between the signal pickup surface and the surface;

[0008] A plurality of drainage holes are provided on the bedrock, which are located outside the signal pickup surface and surround the signal pickup surface.

[0009] In this solution, the anchor holes and drainage holes are both drilled holes formed on the bedrock. The anchor holes serve as mounting holes for anchor rods on the bedrock, and the vibration sensor is further rigidly connected to the bedrock through the anchor rods. The coupling agent layer is used to ensure the quality of the signal picked up by the vibration sensor from the bedrock, and is used to solve the problem of poor pickup quality and signal distortion of vibration signals (especially low-frequency signals and low-amplitude signals) caused by interface reflection when the vibration signal is transmitted from the anchoring glue layer and the anchor rod to the vibration sensor. That is, the vibration sensor is in close contact with the bedrock through the coupling agent layer. The coupling agent layer is used to improve the signal coupling quality between the bedrock and the signal pickup surface, thereby achieving the purpose of ensuring the signal pickup capability of the vibration sensor.

[0010] In such an application, the present solution is further configured to include a drainage hole located outside the signal pickup surface and surrounding the signal pickup surface. The drainage hole is used to increase the effective life of the coupling agent layer. Specifically:

[0011] The coupling agent layer is a thin film structure formed between the vibration sensor and the bedrock by applying the coupling agent to the bedrock or signal pickup surface and then pressing the vibration sensor onto the bedrock. Regarding the effective lifespan of the coupling agent layer, moisture is a major factor in accelerating its aging. Other factors include stress aging (including detachment of the coupling agent from the coupling interface under various stresses, affecting the coupling effect. While this may not cause performance degradation of the coupling agent itself, it is also considered an aging phenomenon requiring maintenance), thermal aging caused by temperature cycling, aging due to ultraviolet radiation from sunlight, oxidation, and corrosion aging. Moisture-induced aging of the coupling agent primarily occurs when the coupling agent absorbs moisture, resulting in reduced strength, softening, and expansion. Aging of the coupling agent significantly degrades its coupling effect, impacting the reliability and lifespan of the geological disaster monitoring system.

[0012] While the performance of available coupling agents has been further optimized, including those with low modulus, UV resistance, and resistance to moisture and heat aging, coupling agent aging remains a major cause of vibration sensor false alarms and failure. From an engineering perspective, vibration monitoring systems for outdoor rock masses in mountainous areas for geological disaster monitoring present high investment and maintenance costs and are difficult to maintain. Therefore, engineers desire coupling agents with longer-lasting aging resistance. However, unlike other vibration monitoring locations (such as bridges), traditional solutions for coupling agent aging protection in mountainous rock masses are not suitable for air curtain protection (high cost and maintenance difficulty), vapor deposition layer cover protection (difficulty in implementation), or molecular-level self-assembled film protection (poor reliability) due to geographical and installation location.

[0013] In response to the above problems, this solution provides the drainage holes:

[0014] On the one hand, the bedrock on mountain slopes is often humid due to condensation, water seepage from above, and rainwater caused by diurnal temperature fluctuations. When the inner side and edges of the coupling agent layer are in a humid environment for a long time, this moisture will accelerate the hydrolysis reaction of the coupling agent layer, causing premature aging of the coupling agent layer, affecting the signal pickup accuracy and reliability of the vibration sensor, as well as the maintenance frequency of the vibration sensor. In this solution, the drainage holes serve as water seepage and evaporation channels on the periphery of the signal pickup surface on the bedrock. For the bonding surface on the bedrock that is used to mate with the signal pickup surface, these drainage holes located on the periphery of the bonding surface can effectively reduce the humidity at the bonding surface position. By reducing the impact of moisture on the aging of the coupling agent layer, the coupling agent layer can achieve the purpose of maintaining reliable signal coupling capability for a long time, ensuring the signal pickup accuracy and reliability of the vibration sensor, and reducing the maintenance frequency of the vibration sensor.

[0015] On the other hand, although the drainage holes have a certain impact on the continuity of the bedrock, for the vibration signal from the side of the vibration sensor, compared with setting an annular groove surrounding the signal picking surface on the bedrock outside the signal picking surface, there is still a rock bridge (continuous bedrock part) between the drainage holes for the vibration signal to be transmitted to the bonding surface. While optimizing the hydrolysis effect of moisture on the bedrock on the coupling agent layer, this solution can still ensure that the vibration sensor can reliably pick up valuable vibration signals. For example, the drainage holes with a smaller aperture than conventional anchor holes (such as an anchor hole with a diameter of 10 mm using an anchor hole with a diameter of 12 mm) are significantly smaller than the wavelength of the vibration wave of the vibration signal. From the perspective of vibration wave energy loss, arranging drainage holes in an area within 30 cm from the bonding surface not only has a significant dehumidification effect on the bonding surface, but also has a relatively small impact on medium and low frequency vibration signals (vibration wave signals of 2 Hz to 30 Hz). Small, this frequency band includes the core frequency band of rock collapse disaster monitoring, which usually includes characteristic signals such as disaster events, locations, and energy. Therefore, this solution can still reliably pick up valuable vibration signals. Compared with medium and low frequency vibration signals, the energy scattering of high-frequency signals by the drainage holes will lead to a certain high-frequency attenuation, and the high-frequency part of the vibration signal usually includes rock fracture signals and friction signals that reflect the precursors of rock collapse disasters. If it is necessary to introduce vibration signal monitoring greater than 50Hz to expand the system monitoring capability, in specific applications, if the type of bedrock is suitable for obtaining drainage holes with a diameter of about 5mm and good water permeability for a long time through conventional drilling methods, the impact of these drainage holes on the quality of high-frequency vibration signal pickup can be ignored. At the same time, by removing the loose layer on the surface of the bedrock, such as the weathered layer, it is generally possible to drill drainage holes with a diameter of 5mm or even 3mm, which can ensure good water permeability for a long time. Therefore, in specific applications, this monitoring system can be set to only pick up the core frequency band of vibration signals in rock collapse disasters: vibration wave signals of 2Hz~30Hz. When the rock mass where the vibration sensor is arranged meets the following conditions: reducing the diameter of the drainage holes (below 6mm), increasing the spacing between the drainage holes, and the distance between the drainage holes and the signal pickup surface (greater than 20cm), vibration signal monitoring greater than 50Hz can also be introduced to optimize the system's ability to pick up precursor signals of rock collapse disasters.

[0016] In a specific embodiment, a step hole is provided on the bedrock, and the anchor hole is a hole section inside the step hole: the opening of the anchor hole is located on the step surface of the step hole;

[0017] The step surface is provided with a fitting surface for coupling with the vibration sensor, and the fitting surface is a plane;

[0018] The openings of the drainage holes are all located on the step surface.

[0019] The above solution is a technical solution that processes the step hole and uses the step surface on the step hole as the surface on the bedrock for fitting with the vibration sensor. In this solution, the outer hole section of the step hole (the channel space outside the step surface) is used as the installation space for the vibration sensor on the bedrock, that is, the vibration sensor is installed to be embedded in the bedrock. Compared with directly installing the vibration sensor on the surface rock wall of the bedrock and exposing it to the outside of the bedrock, the bedrock serves as a natural barrier to the installation space, so that the installation space of the vibration sensor has smaller temperature fluctuations, so as to optimize the thermal aging problem of the coupling agent layer under temperature cycling. At the same time, the setting position of the vibration sensor can effectively avoid the direct influence of the surface water of the bedrock on the hydration of the coupling agent layer, further reducing the influence of the hydration of the coupling agent layer on the degradation of its signal coupling performance. The fitting surface is set to The plane is intended to ensure the effective coupling area between the vibration sensor and the bedrock. In combination with the flat signal pickup surface and the extrusion of the coupling agent layer by the vibration sensor, each position of the signal pickup surface can pass through the coupling agent layer that is tightly and evenly squeezed at each position, forming a large-area, rigid signal coupling relationship with the bedrock, providing the necessary conditions for the vibration sensor to effectively pick up weak but critical low-frequency signals. The position of the drainage hole mouth is that the drainage hole is processed in the step hole, the drainage hole is located on the inner side of the outer hole section, and the drainage hole is sunk in the step hole. Compared with setting the drainage hole on the periphery of the step hole, the drainage hole in this scheme does not have a shallow hole section located on the outermost surface of the bedrock. In this way, it can effectively avoid rainwater from infiltrating into the inner side of the drainage hole through the drainage hole, causing the humidity of the rock mass in the vibration sensor fitting area on the bedrock to be directly affected by rainwater.

[0020] Preferably, the step hole can be obtained by first drilling an anchor hole in the bedrock and then expanding the hole mouth of the anchor hole. The distance between the step surface and the outermost surface of the bedrock is greater than 10 cm. The anchor rod is installed to be partially exposed on the outside of the step surface. The portion of the vibration sensor exposed on the outside of the step surface by the anchor rod is squeezed to be in contact with the fitting surface. The hole section of the step hole located outside the step surface is as follows: the outer ends of the upper hole wall and the lower hole wall are both inclined downward relative to the inner end. In this way, water on the bedrock wall on the upper side of the step hole can be prevented from dripping into the inside of the step hole, and water in the step hole can be promptly discharged, thereby further optimizing the anti-hydrolysis protection capability of the coupling agent layer.

[0021] In a specific embodiment, the axis of the drainage hole is distributed on a cylindrical surface, and the axis of the cylindrical surface is coaxial with the axis of the anchor hole;

[0022] The number of the cylindrical surfaces is greater than 1, and each cylindrical surface is provided with a plurality of drainage holes arranged in an annular manner.

[0023] In this solution, from a two-dimensional perspective, that is, the drainage holes are distributed on several rings whose centers are located on the axis of the anchor hole; from a three-dimensional perspective, that is, the drainage holes are distributed on several cylindrical surfaces whose axes are coaxial with the anchor hole, and the number of rings and the number of cylindrical surfaces are greater than 1. By adopting such a solution, firstly, the anchor hole can be used as an auxiliary hole when processing the drainage hole, so as to realize that the drilling equipment is constrained in the anchor hole before processing the drainage hole. Such a method can effectively reduce the difficulty of drilling the drainage hole for small-diameter drainage holes while realizing efficient processing of the drainage hole. Secondly, the solution in which the number of cylindrical surfaces is greater than 1 and multiple drainage holes are arranged on each cylindrical surface is intended to address the following problems: the multi-ring arrangement of the drainage holes, compared with setting the drainage holes on the same cylindrical surface, has similar drainage and dehumidification capabilities, and the shallower multi-ring shallow holes have less influence on the propagation of vibration waves and are beneficial to ensuring the quality of vibration signal pickup than the single-ring deep holes.

[0024] In a specific embodiment, the anchor rod is anchored in the anchor hole through an anchoring adhesive layer;

[0025] The head end of the anchor rod extends relative to the anchor hole, and a sliding sleeve is provided on the head end and is slidably connected to the anchor rod. A pressure plate is provided on the end of the sliding sleeve close to the bedrock, and the vibration sensor is connected to the side of the pressure plate close to the bedrock through a connecting bolt;

[0026] Also included is a pressure cap threadedly connected to the anchor rod, the pressure cap applies a thrust to the sliding sleeve to image the bedrock, so that the vibration sensor is clamped between the bedrock and the pressure plate;

[0027] The anchor rod is provided with a guide groove parallel to the axis of the anchor rod, and the inner side of the sliding sleeve is provided with a guide rib, and the guide rib is embedded in the guide groove.

[0028] In the above scheme, the anchoring glue layer is used to ensure the anchoring stability of the anchor rod in the anchor hole. The pressure cap forms a structure through the sliding sleeve and the pressure plate to provide the vibration sensor with a thrust to make it fit firmly with the bedrock. The guide groove and the guide rib are used to realize the anti-rotation constraint of the sliding sleeve on the anchor rod, aiming to achieve: when the vibration sensor is fixed to the pressure plate by the connecting bolt and the coupling agent is evenly applied on the signal pickup surface of the vibration sensor, in the process of rotating the pressure cap to push the vibration sensor toward the bedrock, the movement state of the vibration sensor is to always maintain the direction along the axis of the anchor rod and move toward the bedrock in a posture parallel to the fitting surface. In this way, it can effectively prevent the vibration sensor from sliding relative to the bedrock and causing the bedrock to scratch the coupling agent, resulting in the distribution and content of the coupling agent on the signal pickup surface being affected, affecting the density and thickness of each position of the generated coupling agent layer. The connecting bolt is a fixing part between the vibration sensor and the pressure plate, used to stabilize the position of the vibration sensor on the pressure plate. Specifically, since threads are required at the end of the anchor rod to mate with the pressure cap, when the threads intersect the guide groove, the guide groove is machined first, followed by the threads. This effectively ensures thread quality. Preferably, to achieve a couplant layer within the desired thickness range, the pressure cap is tightened with a torque wrench. After tightening to the torque threshold, a pressure cap, threaded onto the anchor rod and acting as a locking nut, is then used to secure the pressure cap.

[0029] In a specific embodiment, the number of vibration sensors between the bedrock and the pressure plate is greater than or equal to 2.

[0030] This solution aims to achieve the following: Monitoring rockfall disasters on mountain slopes generally requires the deployment of multiple vibration signal pickup points. Each pickup point includes an anchor and a vibration sensor coupled to the bedrock through the anchor. In this solution, a single pickup point is equipped with two or more vibration sensors. When each signal pickup point is configured with two or more vibration sensors, the vibration sensors at the same pickup point should produce consistent signal pickup results due to their proximity to each other. This setting of the number of vibration sensors not only optimizes the redundancy of vibration signal pickup at each pickup point, but also allows the difference in vibration signal pickup to be used to assess the reliability of the vibration signals picked up by each vibration sensor. For example, for vibration signal pickup failures commonly caused by aging of the coupling agent layer, if the coupling agent layer of one vibration sensor ages significantly earlier than that of the other vibration sensors, this phenomenon can be detected through the difference in the picked-up signals, prompting maintenance personnel to promptly perform maintenance on the coupling agent layer.

[0031] In a specific embodiment, the invention further comprises a protective cover mounted on the bedrock via an anchor, the protective cover comprising a breathable cover fixed to the anchor;

[0032] The flexible sheet is further comprised, wherein the inner end of the flexible sheet is fixed to the anchor and / or the bedrock, and the outer end of the flexible sheet is fixed to the breathable cover, and the flexible sheet is used to block the gap between the breathable cover and the bedrock;

[0033] The vibration sensor and the anchor rod are both covered in a cover structure formed by a breathable cover and a flexible sheet.

[0034] In the above scheme, the protective cover is used to form an isolation cover on the periphery of the vibration sensor to prevent water flowing along the rock wall from flowing to the signal pickup surface position. At the same time, the signal pickup surface position is partially shielded to reduce the impact of ultraviolet rays on the aging of the anchoring glue layer. At the same time, the semi-open isolation environment can not only reduce the impact of the gas phase environment humidity on the coupling agent layer, but also reduce the impact of temperature fluctuations on the aging of the coupling agent layer. Specifically, the anchoring piece serves as an anchoring structure of the breathable cover on the bedrock. After the breathable cover is fixed, a flexible sheet is used to seal the gap between the bedrock and the breathable cover, so as to utilize the flexible sheet to isolate the influence of water flowing along the bedrock wall on the inner space of the protective cover. The breathable cover is a cover structure with air holes provided thereon, which is used to enable the inner space of the protective cover to generate gas convection with the outside, so as to facilitate the humidity control of the vibration sensor installation environment. The breathable cover can be a standard prefabricated structure, and the flexible sheet can be a flexible sheet structure such as waterproof cloth. After the breathable cover is installed, the flexible sheet is adaptively adjusted in shape to adapt to the gap pattern in the specific installation scenario. Therefore, the combination of the breathable cover and the flexible sheet can make the protective cover universal in various applications.

[0035] In a specific embodiment, the distance between the drainage hole and the vibration sensor is 15 cm to 30 cm, the diameter of the drainage hole is 4 mm to 6 mm, and the length of the drainage hole is 8 cm to 15 cm.

[0036] In practical applications, arranging drainage holes closer to and denser around the vibration sensors can more effectively reduce the effects of moisture on couplant layer aging. However, for vibration signals propagating along the bedrock and picked up by the vibration sensors for rockfall disaster monitoring, the drainage holes act as near-field scattering holes for the vibration signals, significantly impacting the acquisition quality of high-frequency vibration signals. The aperture diameter is significantly smaller than the wavelength of the target high-frequency vibration signal (200Hz), so the impact of the Rayleigh scattering caused by the drainage hole diameter on signal acquisition quality is acceptable. The spacing is used to control the impact of strong near-field scattering on high-frequency signal acquisition quality, and the drainage hole length is used to control the vibration coupling / wave distortion between the vibration sensor signal pickup location and the bedrock. In practical applications, the spacing between adjacent drainage holes is greater than 20 cm to minimize the impact of multi-hole heat dissipation on high-frequency signal acquisition quality. This solution effectively ensures the quality of vibration signal acquisition.

[0037] This solution also relates to a method for monitoring geological disasters of rock collapse on mountain slopes. The method adopts any of the monitoring systems described above to realize geological disaster monitoring of rock collapse on bedrock, and the vibration sensor picks up vibration signals with a frequency lower than 200Hz.

[0038] The monitoring method described above is based on the monitoring system described above and is used to monitor rock collapse geological disasters on mountain slopes. In practice, the high-frequency band of rock fracture vibration signals, which serve as precursor signals for rock collapse geological disaster monitoring, is typically less than 500 Hz. Because drainage holes are relatively sensitive to the signal pickup quality of high-frequency vibration signals, the vibration sensor is configured to pick up seismic waves with frequencies below 200 Hz as vibration signals. The specific frequency range can be 2 Hz to 200 Hz. This vibration signal pickup scheme not only ensures the pickup quality of signals in various frequency bands, but also covers the core frequency band commonly used for rock collapse geological disaster monitoring. If vibration signals with frequencies higher than 200 Hz (e.g., 200 Hz to 500 Hz) need to be monitored, a separate signal pickup point can be set up in the system. At this signal pickup point, the vibration sensor is fixed to the bedrock using only anchor rods, and signal coupling with the bedrock is achieved through layers of coupling agent. Drain holes are not placed around the vibration signal pickup location on the bedrock.

[0039] In a specific embodiment, the anchor rod is anchored in the anchor hole by an anchoring adhesive layer of epoxy resin composite material filled with steel grit;

[0040] The epoxy resin composite material is injected into the anchor hole by vacuum negative pressure grouting method, and the anchor rod anchoring method is: closing the anchor hole mouth and vacuuming and exhausting the anchor hole; injecting the epoxy resin composite material into the anchor hole that has been vacuumed and exhausted; and inserting the anchor rod into the epoxy resin composite material in the anchor hole.

[0041] In the above scheme, a steel grit-modified epoxy resin composite material is used as the anchoring adhesive layer, aiming to reduce the impact of anchor rod installation on the attenuation and phase error of vibration signals (especially high-frequency signals in the spectrum band) from the perspective of impedance mismatch. The vacuum negative pressure grouting method is used to reduce the porosity in the anchoring adhesive layer, and the porosity that can reach 10% under traditional normal pressure construction technology can be controlled to below 0.5%, so that the anchor rod can achieve an almost void-free anchoring state, thereby achieving the purpose of reducing the impact of anchor rod anchoring on the fidelity of high-frequency signals picked up by the vibration sensor.

[0042] In a specific embodiment, the method for setting the drainage hole and the vibration sensor is:

[0043] Confirm the signal source location of the vibration signal on the bedrock and the fitting position of the vibration sensor on the bedrock;

[0044] According to the signal source position and the fitting position, the drainage hole is arranged on a side of the fitting position away from the signal source position;

[0045] The vibration sensor is installed after the drainage hole is processed. The vibration sensor is installed as follows:

[0046] Evenly applying the coupling agent forming the coupling agent layer on the signal pickup surface of the vibration sensor;

[0047] Press the vibration sensor to the bedrock, and provide a pushing force of a set threshold to the vibration sensor through the anchor rod;

[0048] Scrape off the coupling agent overflow around the vibration sensor and outside the signal pickup surface due to the pushing;

[0049] During the process of the monitoring system performing geological disaster monitoring, the pickup quality of the vibration signal is tested by actively knocking on the bedrock, and the active knocking includes active knocking under a set time plan and / or active knocking after experiencing extreme weather.

[0050] In the above scheme, the signal source position is the position where the vibration signal may be generated, which is usually an area. In the monitoring of rock collapse disasters on slopes, multiple areas can usually be determined on the slope based on the on-site geological survey before the system is arranged. The fitting position is the position on the bedrock suitable for installing the vibration sensor. When the above two positions are obtained, the orientation of the signal source position relative to the fitting position can be confirmed, and the setting orientation of the drainage hole relative to the fitting position can be further confirmed under the guidance of the orientation. Such means are used to achieve: reducing the influence of the drainage hole on the vibration signal pickup quality caused by directional shielding during the propagation of the vibration signal in the bedrock. The setting method of the coupling agent layer is intended to achieve: using the signal pickup surface to be smoother than the bedrock surface to better control the amount of coupling agent applied and uniform thickness at each position, and before the coupling agent is pressed against the bedrock, the surface of the bedrock surface for fitting with the coupling agent is cleaned. Specifically, a wire brush can be used to scrape the fitting surface flat. After adjustment, alcohol is used to thoroughly remove dust. The control of the pushing force is intended to control the thickness of the coupling agent layer formed to avoid the coupling agent layer being too thick or too thin (the preferred setting is 0.2mm-0.3mm). The specific threshold value needs to be set according to the size of the sensor signal pickup surface and the specific coupling agent used. The purpose of scraping the coupling agent overflow on the outside of the signal pickup surface is to avoid the formation of an elastic coupling layer on the periphery of the signal pickup surface. On the one hand, the elastic coupling layer serves as a supporting layer between the bedrock and the vibration sensor, which is not conducive to ensuring the effective vibration signal propagation area between the vibration sensor and the bedrock. At the same time, from the perspective of signal attenuation and parasitic vibration, it will also cause a certain degree of distortion of the picked-up vibration signal. On the other hand, the stress concentration occurring on the edge overflow may easily lead to premature crack aging of the coupling agent layer due to crack expansion. On the other hand, the water absorption channel and water storage space formed by the bedrock and the vibration sensor have a significant impact on the aging rate of the coupling agent layer. The active knocking can be done by hammering to confirm whether the vibration sensor can clearly and stably capture this part of the artificial vibration signal, and by comparing the signal amplitude, waveform characteristics, and lack of low-frequency response with the expected signal pickup results, the signal coupling performance of the coupling agent layer and the performance of the vibration sensor itself are detected. The set time knocking is to regularly verify the pickup performance of the vibration signal, and the knocking after experiencing extreme weather is to verify the pickup performance of the vibration signal in extreme environment.

[0051] The present invention has the following beneficial effects:

[0052] On the one hand, this solution addresses the common moisture problem of bedrock on mountain slopes. When the inner side and edges of the coupling agent layer are in a humid environment for a long time, the coupling agent layer may age prematurely, affecting the signal pickup accuracy and reliability of the vibration sensor, as well as the maintenance frequency of the vibration sensor. The drainage holes are provided as water seepage and evaporation channels on the periphery of the signal pickup surface on the bedrock. For the bonding surface on the bedrock that is bonded to the signal pickup surface, these drainage holes located on the periphery of the bonding surface can effectively reduce the humidity at the bonding surface. By reducing the effect of moisture on the aging of the coupling agent layer, the coupling agent layer can achieve the purpose of maintaining reliable signal coupling capabilities for a long time, ensuring the signal pickup accuracy and reliability of the vibration sensor, and reducing the maintenance frequency of the vibration sensor.

[0053] On the other hand, this solution has a certain impact on the continuity of the bedrock due to the drainage holes. However, for the vibration signal from the side of the vibration sensor, there is still a rock bridge (continuous bedrock portion) between the drainage holes for the vibration signal to be transmitted to the bonding surface. While optimizing the hydrolysis effect of moisture on the bedrock on the coupling agent layer, this solution can still ensure that the vibration sensor can reliably pick up valuable vibration signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a cross-sectional view of a specific application embodiment of the mountain slope rock collapse geological disaster monitoring system described in this solution;

[0055] Figure 2 for Figure 1 A partial enlarged view of part A;

[0056] Figure 3 This is a partial schematic diagram of the system, which reflects the way in which the step holes are opened, the fitting surface, and the drainage holes are set on the step holes, in a specific application embodiment of the mountain slope rock collapse geological disaster monitoring system described in this scheme.

[0057] The reference numerals in the accompanying drawings are: 1. bedrock, 2. anchor rod, 3. vibration sensor, 4. flexible sheet, 5. breathable cover, 6. anchoring rubber layer, 7. coupling agent layer, 8. pressure plate, 9. guide groove, 10. connecting bolt, 11. sliding sleeve, 12. pressure cap, 13. step hole, 14. anchor hole, 15. fitting surface, 16. drainage hole, 17. anchor. DETAILED DESCRIPTION

[0058] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments:

[0059] Example 1:

[0060] like Figures 1 to 3As shown, a mountain slope rock collapse geological disaster monitoring system is provided. The monitoring system monitors rock collapse geological disasters on the bedrock 1 based on vibration signals picked up by a vibration sensor 3 on the bedrock 1. In the system, the vibration sensor 3 is fixed to the bedrock 1 via an anchor rod 2 installed in an anchor hole 14. The signal pickup surface of the vibration sensor 3 is in contact with the surface of the bedrock 1, and a coupling agent layer 7 is provided between the signal pickup surface and the surface.

[0061] A plurality of drainage holes 16 are provided on the bedrock 1 , which are located outside the signal pickup surface and surround the signal pickup surface.

[0062] In this solution, the anchor hole 14 and the drainage hole 16 are both drilled holes formed on the bedrock 1. The anchor hole 14 serves as a mounting hole for the anchor rod 2 on the bedrock 1, and further rigidly connects the vibration sensor 3 to the bedrock 1 through the anchor rod 2. The coupling agent layer 7 is used to ensure the quality of the signal picked up by the vibration sensor 3 from the bedrock 1, and is used to solve the problem of poor pickup quality and signal distortion of vibration signals (especially low-frequency signals and low-amplitude signals) caused by interface reflection when the vibration signal is transmitted from the anchoring glue layer 6 and the anchor rod 2 to the vibration sensor 3. That is, the vibration sensor 3 is in close contact with the bedrock 1 through the coupling agent layer 7. The coupling agent layer 7 is used to improve the signal coupling quality between the bedrock 1 and the signal pickup surface. In this embodiment, silicone grease is used to maximize the vibration energy transmission efficiency to achieve the purpose of ensuring the signal pickup capability of the vibration sensor 3.

[0063] Before applying silicone grease, the coupling surfaces between the bedrock 1 and the vibration sensor 3 should be thoroughly cleaned and polished (only for the bedrock 1). If a detergent is used to remove dust and oil (generally only for the vibration sensor 3), compressed air should be used to dry the coupling surfaces to ensure good adhesion and durability of the coupling agent layer 7.

[0064] In such an application, the present solution is further configured to include a drainage hole 16 located outside the signal pickup surface and surrounding the signal pickup surface. The drainage hole 16 is used to increase the effective life of the coupling agent layer 7. Specifically:

[0065] The coupling agent layer 7 is a thin film structure formed between the vibration sensor 3 and the bedrock 1 by applying the coupling agent to the bedrock 1 or signal pickup surface and then pressing the vibration sensor 3 onto the bedrock 1. Regarding the effective lifespan of the coupling agent layer 7, moisture is a major factor in accelerating the aging of the coupling agent layer 7. Other factors include stress aging (including detachment of the coupling agent from the coupling interface under various stresses, affecting the coupling effect. While this may not cause degradation of the coupling agent itself, it is also considered an aging phenomenon requiring maintenance), thermal aging caused by temperature cycling, aging due to ultraviolet radiation from sunlight, oxidation, and corrosion aging. Moisture-induced aging of the coupling agent primarily occurs when the coupling agent absorbs moisture, resulting in reduced strength, softening, and expansion. Aging of the coupling agent significantly degrades its coupling effect, impacting the reliability and lifespan of the geological disaster monitoring system.

[0066] While the performance of existing coupling agents has been further optimized, and coupling agents with low modulus, UV resistance, and resistance to moisture and heat aging can be selected for outdoor rock mass geological disaster monitoring in mountainous areas, coupling agent aging remains a major cause of false alarms and failure of vibration sensor 3. From an engineering perspective, systems for vibration monitoring in mountainous outdoor rock masses for geological disaster monitoring face high investment and maintenance costs and difficulties. Therefore, engineers desire coupling agents with longer-lasting aging resistance. However, unlike other vibration monitoring locations (such as bridges), traditional solutions for coupling agent aging protection in mountainous rock masses are not suitable for air curtain protection (high cost and maintenance difficulty), vapor deposition layer cover protection (high implementation difficulty), or molecular self-assembled film protection (low reliability) due to geographical and installation location.

[0067] In view of the above problems, this solution provides the drainage hole 16:

[0068] On the one hand, the bedrock 1 on the slope of a mountainous area usually has moisture problems caused by condensation, water seepage from above, rainwater, etc. due to diurnal temperature fluctuations. When the inner side and edge of the coupling agent layer 7 are in a humid environment for a long time, this moisture will accelerate the hydrolysis reaction of the coupling agent layer 7, causing premature aging of the coupling agent layer 7 and affecting the signal pickup accuracy and reliability of the vibration sensor 3, as well as the maintenance frequency of the vibration sensor 3. In this solution, the drainage holes 16 serve as water seepage and evaporation channels on the periphery of the signal pickup surface on the bedrock 1. For the bonding surface 15 on the bedrock 1 used to bond with the signal pickup surface, these drainage holes 16 located on the periphery of the bonding surface 15 can effectively reduce the humidity at the bonding surface 15. By reducing the effect of moisture on the aging of the coupling agent layer 7, the coupling agent layer 7 can achieve the purpose of maintaining reliable signal coupling capability for a long time, ensuring the signal pickup accuracy and reliability of the vibration sensor 3, and reducing the maintenance frequency of the vibration sensor 3.

[0069] On the other hand, although the drainage holes 16 have a certain impact on the continuity of the bedrock 1, for the vibration signal from the side of the vibration sensor 3, compared with setting an annular groove surrounding the signal picking surface on the bedrock 1 on the periphery of the signal picking surface, there is still a rock bridge (continuous bedrock 1 part) between the drainage holes 16 for the vibration signal to be transmitted to the bonding surface 15. This solution can optimize the hydrolysis effect of moisture on the bedrock 1 on the coupling agent layer 7 while still ensuring that the vibration sensor 3 can reliably pick up valuable vibration signals. For example, the drainage holes 16 with a smaller aperture than the conventional anchor rod 2 hole (such as an anchor rod 2 with a diameter of 10 mm using an anchor rod 2 hole with a hole diameter of 12 mm) have a smaller aperture than the conventional anchor rod 2 hole (such as an anchor rod 2 with a diameter of 10 mm using an anchor rod 2 hole with a hole diameter of 12 mm) because the aperture is significantly smaller than the wavelength of the vibration wave of the vibration signal. From the perspective of vibration wave energy loss, etc., arranging the drainage holes 16 in an area within 30 cm from the bonding surface 15 not only has a significant dehumidification effect on the bonding surface 15, but also has a significant effect on the low and medium frequency vibration signals (vibration waves of 2 Hz to 30 Hz). The influence of the signal) is relatively small. This frequency band includes the core frequency band of rock collapse disaster monitoring, which usually includes characteristic signals such as disaster events, locations, and energy. Therefore, this solution can still reliably pick up valuable vibration signals. Compared with medium and low frequency vibration signals, the energy scattering of high-frequency signals by the drainage hole 16 will cause a certain high-frequency attenuation, and the high-frequency part of the vibration signal usually includes rock fracture signals and friction signals that reflect the precursors of rock collapse disasters. If it is necessary to introduce vibration signal monitoring greater than 50Hz to expand the system monitoring capability, in specific applications, if the type of bedrock 1 is suitable for obtaining drainage holes 16 with a diameter of about 5mm and good water permeability for a long time through conventional drilling methods, the influence of these drainage holes 16 on the quality of picking up high-frequency vibration signals can be ignored. At the same time, after removing the loose layer on the surface of the bedrock 1, such as the weathered layer, it is generally possible to drill drainage holes 16 with a diameter of 5mm or even 3mm, which can ensure good water permeability for a long time. Therefore, in specific applications, this monitoring system can be set to only pick up the core frequency band of vibration signals in rock collapse disasters: vibration wave signals of 2Hz~30Hz. When the rock mass at the location where the vibration sensor 3 is arranged meets the following conditions: reducing the aperture of the drainage hole 16 (below 6mm), increasing the spacing between the drainage holes 16, and the spacing between the drainage holes 16 and the signal pickup surface (greater than 20cm), vibration signal monitoring greater than 50Hz can also be introduced to optimize the system's ability to pick up precursor signals of rock collapse disasters.

[0070] In this embodiment, regarding the installation location of the vibration sensor 3 on the bedrock 1, based on geological surveys, historical rockfall records, and topography (steep cliffs, grooves, and accumulation areas at the foot of the slope), the most likely rockfall initiation area, main movement path, and accumulation area are identified, and the approximate installation location of the vibration sensor 3 on the bedrock 1 is determined based on the identification results. For key areas for geological disaster monitoring, such as the initiation area and around human activity areas, vibration signal pickup points are densely deployed. To reduce the attenuation of vibration signals during transmission in the bedrock 1, the specific location of the vibration sensor 3 should avoid loose rock layers. If there is no such naturally exposed surface of the bedrock 1, the method of removing the loose surface layer of the bedrock 1 and then installing the vibration sensor 3 is adopted to ensure the quality of vibration signal pickup.

[0071] The anchoring method of the anchor rod 2 can be: drilling an anchor hole 14 slightly larger than the diameter of the anchor rod 2, the specific depth of which is determined according to the strength of the bedrock 1, then using compressed air to clean the dust in the anchor hole 14, and then using the negative pressure perfusion method to inject anchoring glue, and then anchoring the anchor rod 2. After the anchor rod 2 is stabilized, the vibration sensor 3 is installed, which is coupled to the bedrock 1 signal through the coupling agent layer 7.

[0072] The vibration sensor 3 is preferably a multi-axis sensor to better adapt to multi-directional vibration signals.

[0073] For the direction of the vibration signal source with a clear direction, in order to ensure the quality of signal pickup, it is preferred to process the bedrock 1 plane (the fitting surface 15 in Example 2) coupled to the signal pickup surface so that after the vibration sensor 3 is coupled thereto, the sensitive axis of the vibration sensor 3 points to the direction of the vibration signal source.

[0074] After completing the setup of this system, verify whether this system can meet the requirements for picking up vibration signals through manual tapping.

[0075] Preferably, after processing the drainage hole 16 and cleaning the dust inside the drainage hole, a metal mesh is used to cover the opening of the drainage hole 16. The metal mesh allows the drainage hole 16 to still be connected to the external phase through the mesh holes on it. At the same time, the metal mesh can be used to reduce the cavity resonance of the drainage hole 16, which is beneficial to ensuring the signal pickup quality of the vibration sensor 3.

[0076] Preferably, the coupling surface on the bedrock used for coupling with the vibration sensor 3 is generally perpendicular to the anchor rod 2. In order to reduce the influence of the drainage hole 16 on the signal pickup quality and improve the anti-hydrolysis aging performance of the coupling agent layer 7, when drilling the drainage hole 16, the drainage hole 16 is drilled as an inclined hole inclined relative to the anchor hole 14, and specifically: the hole mouth of the drainage hole 16 is relative to the bottom of the hole, and the distance from the hole mouth to the anchor hole 14 is greater than the distance from the bottom of the hole to the anchor hole 14.

[0077] Example 2:

[0078] This embodiment is further refined based on the embodiment 1:

[0079] The bedrock 1 is provided with a stepped hole 13, and the anchor hole 14 is a hole section inside the stepped hole 13: the opening of the anchor hole 14 is located on the stepped surface of the stepped hole 13;

[0080] The step surface is provided with a fitting surface 15 for coupling with the vibration sensor 3, and the fitting surface 15 is a plane;

[0081] The openings of the drainage holes 16 are all located on the step surface.

[0082] The above solution is a technical solution that processes the step hole 13 and uses the step surface on the step hole 13 as the surface on the bedrock 1 for fitting with the vibration sensor 3. In this solution, the outer hole section of the step hole 13 (the channel space outside the step surface) serves as the installation space for the vibration sensor 3 on the bedrock 1, that is, the vibration sensor 3 is installed to be embedded in the bedrock 1. Compared with directly installing the vibration sensor 3 on the surface rock wall of the bedrock 1 and exposing it to the outside of the bedrock 1, the bedrock 1 serves as a natural barrier for the installation space, so that the installation space of the vibration sensor 3 has smaller temperature fluctuations, thereby optimizing the thermal aging problem of the coupling agent layer 7 under temperature cycling. At the same time, the setting position of the vibration sensor 3 can effectively avoid the direct influence of the surface water of the bedrock 1 on the hydration of the coupling agent layer 7, further reducing the influence of the hydration of the coupling agent layer 7 on the degradation of its signal coupling performance. The fitting surface 15 is set to be a plane, While ensuring the effective coupling area between the vibration sensor 3 and the bedrock 1, combined with the flat signal pickup surface and the extrusion of the coupling agent layer 7 by the vibration sensor 3, each position of the signal pickup surface can form a large-area, rigid signal coupling relationship with the bedrock 1 through the coupling agent layer 7 that is tightly and evenly squeezed at each position, providing the necessary conditions for the vibration sensor 3 to effectively pick up weak but critical low-frequency signals. The position of the drainage hole 16 is that the drainage hole 16 is processed in the step hole 13. The drainage hole 16 is located on the inner side of the outer hole section. The drainage hole 16 is sunken in the step hole 13. Compared with setting the drainage hole 16 on the periphery of the step hole 13, the drainage hole 16 in this solution does not have a shallow hole section located on the outermost surface of the bedrock 1. In this way, it can effectively prevent rainwater from infiltrating into the inner side of the drainage hole 16 through the drainage hole 16, resulting in the humidity of the rock mass in the area where the vibration sensor 3 is attached on the bedrock 1 being directly affected by rainwater.

[0083] Preferably, the step hole 13 can be obtained by first drilling an anchor hole 14 on the bedrock 1 and then expanding the hole mouth of the anchor hole 14. The distance between the step surface and the outermost surface of the bedrock 1 is greater than 10 cm. The anchor rod 2 is installed to be partially exposed on the outside of the step surface. The portion of the vibration sensor 3 exposed on the outside of the step surface by the anchor rod 2 is squeezed to be in contact with the contact surface 15. The hole section on the step hole 13 located outside the step surface is as follows: the outer ends of the upper hole wall and the lower hole wall are both inclined downward relative to the inner end. In this way, water on the rock wall of the bedrock 1 above the step hole 13 can be prevented from dripping into the inside of the step hole 13, and the water in the step hole 13 can be promptly discharged, thereby further optimizing the anti-hydrolysis protection capability of the coupling agent layer 7.

[0084] Example 3:

[0085] This embodiment is further refined based on the embodiment 1:

[0086] The axis of the drainage hole 16 is distributed on a cylindrical surface, and the axis of the cylindrical surface is coaxial with the axis of the anchor hole 14;

[0087] The number of the cylindrical surfaces is greater than 1, and a plurality of drainage holes 16 are arranged in an annular manner on each cylindrical surface.

[0088] In this solution, from a two-dimensional perspective, the drainage holes 16 are distributed on several rings whose centers are located on the axis of the anchor hole 14; from a three-dimensional perspective, the drainage holes 16 are distributed on several cylindrical surfaces whose axes are coaxial with the anchor hole 14. The number of rings and the number of cylindrical surfaces are greater than 1. By adopting such a solution, first, the anchor hole 14 can be used as an auxiliary hole for processing the drainage hole 16, so that the drilling equipment can be constrained in the anchor hole 14 before processing the drainage hole 16. This method can effectively reduce the difficulty of drilling the drainage hole 16 for small-diameter drainage holes 16 while achieving efficient processing of the drainage hole 16. Secondly, the solution in which the number of cylindrical surfaces is greater than 1 and multiple drainage holes 16 are arranged on each cylindrical surface is intended to address the following problems: compared with setting the drainage holes 16 on the same cylindrical surface, the multi-ring shallow holes with shallower depth have less influence on the propagation of vibration waves and are beneficial to ensuring the quality of vibration signal pickup than the single-ring deep holes under similar drainage and moisture removal capabilities.

[0089] Example 4:

[0090] This embodiment is further refined based on the embodiment 1:

[0091] The anchor rod 2 is anchored in the anchor hole 14 through the anchoring adhesive layer 6;

[0092] The head end of the anchor rod 2 extends relative to the anchor hole 14. A sliding sleeve 11 is provided on the head end and is slidably connected to the anchor rod 2. A pressure plate 8 is provided on the end of the sliding sleeve 11 close to the bedrock 1. The vibration sensor 3 is connected to the side of the pressure plate 8 close to the bedrock 1 via a connecting bolt 10.

[0093] The device further comprises a pressure cap 12 threadedly connected to the anchor rod 2. The pressure cap 12 applies a thrust to the sliding sleeve 11 to image the bedrock 1, so that the vibration sensor 3 is clamped between the bedrock 1 and the pressure plate 8.

[0094] The anchor rod 2 is provided with a guide groove 9 parallel to the axis of the anchor rod 2 , and the inner side of the sliding sleeve 11 is provided with a guide ridge, which is embedded in the guide groove 9 .

[0095] In the above scheme, the anchoring glue layer 6 is used to ensure the anchoring stability of the anchor rod 2 in the anchor hole 14. The pressure cap 12 forms a structure through the sliding sleeve 11 and the pressure plate 8 to provide the vibration sensor 3 with a thrust to make it fit firmly with the bedrock 1. The guide groove 9 and the guide edge are used to realize the anti-rotation constraint of the sliding sleeve 11 on the anchor rod 2, which is intended to achieve: when the vibration sensor 3 is fixed to the pressure plate 8 by the connecting bolt 10 and the coupling agent is evenly applied on the signal pickup surface of the vibration sensor 3, the pressure cap 12 is rotated to push the vibration sensor During its movement toward bedrock 1, vibration sensor 3 maintains its position along the axis of anchor rod 2 and parallel to contact surface 15. This effectively prevents slippage of vibration sensor 3 relative to bedrock 1, which could cause bedrock 1 to scrape the coupling agent, affecting the distribution and content of the coupling agent on the signal pickup surface, and affecting the density and thickness of the generated coupling agent layer 7 at various locations. The connecting bolt 10 serves as a fastener between vibration sensor 3 and pressure plate 8, securing the position of vibration sensor 3 on pressure plate 8. Specifically, because threads are required at the end of anchor rod 2 to mate with pressure cap 12, when these threads intersect with guide groove 9, the guide groove 9 is machined first, followed by the threads. This effectively ensures the quality of the threads. Preferably, in order to obtain the coupling agent layer 7 in the required thickness range, the pressure cap 12 is tightened with a torque wrench, and after being tightened to the torque threshold, a pressure cap 12 threadedly connected to the anchor rod 2 is used as a locking nut to prevent the pressure cap 12 from loosening and reinforce it.

[0096] Example 5:

[0097] This embodiment is further refined based on embodiment 4:

[0098] The number of the vibration sensors 3 between the bedrock 1 and the pressure plate 8 is greater than or equal to 2.

[0099] This solution aims to achieve the following: For monitoring rock collapse disasters on mountain slopes, multiple vibration signal pickup points are generally required. Each pickup point includes an anchor rod 2 and a vibration sensor 3 coupled to the bedrock 1 through the anchor rod 2. In this solution, a single pickup point has two or more vibration sensors 3. For each signal pickup point, when each signal pickup point is configured to have two or more vibration sensors 3, the vibration sensors 3 at the same signal pickup point should have consistent signal pickup results due to their proximity to each other. This setting of the number of vibration sensors 3 not only optimizes the vibration signal pickup redundancy capability of the signal pickup points, but also allows the difference in vibration signal pickup to be used to determine the reliability of the vibration signals picked up by each vibration sensor 3. For example, for a common vibration signal pickup failure caused by aging of the coupling agent layer 7, if the coupling agent layer 7 of one vibration sensor 3 ages significantly earlier than that of other vibration sensors 3, this phenomenon can be detected through the difference in the picked-up signals, prompting maintenance personnel to promptly perform maintenance on the coupling agent layer 7.

[0100] Example 6:

[0101] This embodiment is further refined based on the embodiment 1:

[0102] It also includes a protective cover installed on the bedrock 1 through an anchor 17, and the protective cover includes a breathable cover 5 fixed on the anchor 17;

[0103] It also includes a flexible sheet 4, the inner end of the flexible sheet 4 is fixed to the anchor 17 and / or the bedrock 1, and the outer end of the flexible sheet 4 is fixed to the breathable cover 5, and the flexible sheet 4 is used to block the gap between the breathable cover 5 and the bedrock 1;

[0104] The vibration sensor 3 and the anchor rod 2 are both covered in a housing structure formed by a breathable cover 5 and a flexible sheet 4 .

[0105] In the above scheme, the protective cover is used to form an isolation cover on the periphery of the vibration sensor 3 to prevent water flowing along the rock wall from flowing to the signal pickup surface position. At the same time, the signal pickup surface position is partially shielded to reduce the influence of ultraviolet rays on the aging of the anchoring glue layer 6. At the same time, the semi-open isolation environment can not only reduce the influence of the gas phase environment humidity on the coupling agent layer 7, but also reduce the influence of temperature fluctuations on the aging of the coupling agent layer 7. Specifically, the anchor 17 serves as an anchoring structure of the breathable cover 5 on the bedrock 1. After the breathable cover 5 is fixed, the flexible sheet 4 is used to seal the gap between the bedrock 1 and the breathable cover 5, so as to utilize the flexible sheet 4 to isolate the influence of the water flowing along the rock wall of the bedrock 1 on the inner space of the protective cover. The breathable cover 5 is a cover structure with air holes provided thereon, which is used to enable the inner space of the protective cover to generate gas convection with the outside, so as to facilitate the humidity control of the installation environment of the vibration sensor 3. The breathable cover 5 can be a standard prefabricated structure, and the flexible sheet 4 can be a flexible sheet 4 structure such as waterproof cloth. After the breathable cover 5 is installed, the flexible sheet 4 is adaptively adjusted in shape to adapt to the gap style in the specific installation scenario. Therefore, the combination of the breathable cover 5 and the flexible sheet 4 can make the protective cover universal in various applications.

[0106] In this embodiment, the breathable cover 5 is a steel protective cage.

[0107] Example 7:

[0108] This embodiment is further refined based on the embodiment 1:

[0109] The distance between the drainage hole 16 and the vibration sensor 3 is 15 cm to 30 cm, the diameter of the drainage hole 16 is 4 mm to 6 mm, and the length of the drainage hole 16 is 8 cm to 15 cm.

[0110] In practical applications, arranging drainage holes 16 closer to and more densely surrounding the vibration sensor 3 can more effectively reduce the effects of moisture on the aging of the coupling agent layer 7. However, for the vibration signal propagating along the bedrock 1 and picked up by the vibration sensor 3 for rockfall disaster monitoring, the drainage holes 16 act as near-field scattering holes for the vibration signal, which has a relatively significant impact on the signal acquisition quality of the high-frequency vibration signal. The aperture size is significantly smaller than the wavelength of the target high-frequency vibration signal (200 Hz), so the impact of the Rayleigh scattering caused by the aperture of the drainage holes 16 on the signal acquisition quality is acceptable. The spacing is used to control the impact of strong near-field scattering on the high-frequency signal acquisition quality, and the length of the drainage holes 16 is used to control the vibration coupling degree / vibration wave distortion between the signal pickup location of the vibration sensor 3 and the bedrock 1. In practical applications, the spacing between adjacent drainage holes 16 is greater than 20 cm to minimize the impact of the superposition of multi-hole heat dissipation on the high-frequency signal acquisition quality. This solution effectively ensures the signal acquisition quality of the vibration signal.

[0111] Example 8:

[0112] This solution provides a method for monitoring rock collapse geological disasters on mountain slopes. The method uses the monitoring system described in any of the above embodiments to monitor rock collapse geological disasters on bedrock 1. The vibration sensor 3 picks up vibration signals with a frequency lower than 200 Hz.

[0113] The monitoring method is based on the monitoring system described above and is used to monitor rock collapse geological disasters on mountain slopes. In practice, the high-frequency band of rock fracture vibration signals, which serve as precursor signals for rock collapse geological disaster monitoring, is typically less than 500 Hz. Because the drainage holes 16 are relatively sensitive to the signal pickup quality of high-frequency vibration signals, the vibration sensor 3 is configured to pick up seismic waves with frequencies below 200 Hz as vibration signals. The specific frequency range can be 2 Hz to 200 Hz. This vibration signal pickup scheme not only ensures the pickup quality of signals in various frequency bands, but also covers the core frequency band commonly used for rock collapse geological disaster monitoring. If vibration signals with frequencies higher than 200 Hz (e.g., 200 Hz to 500 Hz) need to be monitored, a separate signal pickup point can be set up in the system. At this signal pickup point, only the anchor rod 2 is used to secure the vibration sensor 3 to the bedrock 1, and the signal coupling with the bedrock 1 is achieved through the coupling agent layer 7. The drainage holes 16 are not provided around the vibration signal pickup location on the bedrock 1.

[0114] Example 9:

[0115] This embodiment is further refined based on the embodiment 8:

[0116] The anchor rod 2 is anchored in the anchor hole 14 by an anchoring adhesive layer 6 of epoxy resin composite material filled with steel grit;

[0117] The epoxy resin composite material is injected into the anchor hole 14 by a vacuum negative pressure grouting method, and the anchoring method of the anchor rod 2 is: closing the opening of the anchor hole 14 and vacuuming and exhausting the anchor hole 14; injecting the epoxy resin composite material into the vacuumed and exhausted anchor hole 14; and inserting the anchor rod 2 into the epoxy resin composite material in the anchor hole 14.

[0118] In the above scheme, an epoxy resin composite material modified with steel grit is used as the anchoring adhesive layer 6, aiming to reduce the influence of the anchor rod 2 on the attenuation of the vibration signal (especially the high-frequency signal in the spectrum band) and the phase error from the perspective of impedance mismatch. The vacuum negative pressure grouting method is used to reduce the porosity in the anchoring adhesive layer 6, and the porosity that can reach 10% under the traditional normal pressure construction process can be controlled to below 0.5%, so that the anchor rod 2 can achieve an approximately void-free anchoring state, thereby achieving the purpose of reducing the influence of the anchoring of the anchor rod 2 on the fidelity of the high-frequency signal picked up by the vibration sensor 3.

[0119] Example 10:

[0120] This embodiment is further refined based on the embodiment 1:

[0121] The arrangement method of the drainage hole 16 and the vibration sensor 3 is as follows:

[0122] Confirm the signal source position of the vibration signal on the bedrock 1 and the fitting position of the vibration sensor 3 on the bedrock 1;

[0123] According to the signal source position and the fitting position, the drainage hole 16 is arranged on a side of the fitting position away from the signal source position;

[0124] The vibration sensor 3 is installed after the drainage hole 16 is processed. The vibration sensor 3 is installed as follows:

[0125] Evenly apply the coupling agent forming the coupling agent layer 7 on the signal pickup surface of the vibration sensor 3;

[0126] Press the vibration sensor 3 toward the bedrock 1, and provide a pushing force of a set threshold value to the vibration sensor 3 through the anchor rod 2;

[0127] Scrape off the coupling agent overflow around the vibration sensor 3 and outside the signal pickup surface due to the pushing;

[0128] During the process of the monitoring system performing geological disaster monitoring, the pickup quality of the vibration signal is tested by actively knocking on the bedrock 1, and the active knocking includes active knocking under a set time plan and / or active knocking after experiencing extreme weather.

[0129] In the above scheme, the signal source position is the position where the vibration signal may be generated, which is usually an area. In the monitoring of rock collapse disasters on slopes, multiple areas can usually be determined on the slope based on the on-site geological survey before the system is arranged. The fitting position is the position on the bedrock 1 that is suitable for installing the vibration sensor 3. When the above two positions are obtained, the orientation of the signal source position relative to the fitting position can be confirmed, and the setting orientation of the drainage hole 16 relative to the fitting position can be further confirmed under the guidance of the orientation. Such means are adopted to achieve: reducing the influence of the drainage hole 16 on the vibration signal pickup quality caused by directional shielding during the propagation of the vibration signal in the bedrock 1. The setting method of the coupling agent layer 7 is intended to achieve: using the signal pickup surface to be smoother than the surface of the bedrock 1 to better control the amount of coupling agent applied and uniform the thickness of each position, and before the coupling agent is pressed against the bedrock 1, the surface of the bedrock 1 for the position where the coupling agent is fitted is cleaned. Specifically, a wire brush can be used to scrape the fitting surface 15 After smoothing, use alcohol to thoroughly remove dust. The purpose of controlling the pushing force is to control the thickness of the formed coupling agent layer 7 to prevent the coupling agent layer 7 from being too thick or too thin (preferably set to 0.2mm-0.3mm). The specific threshold value needs to be set according to the size of the sensor signal pickup surface and the specific coupling agent used. Scraping the coupling agent overflow outside the signal pickup surface is to achieve the following: avoid the formation of an elastic coupling layer on the periphery of the signal pickup surface. On the one hand, this elastic coupling layer serves as a supporting layer between the bedrock 1 and the vibration sensor 3, which is not conducive to ensuring an effective vibration signal propagation area between the vibration sensor 3 and the bedrock 1. At the same time, from the perspective of signal attenuation and parasitic vibration, it will also cause a certain degree of distortion in the picked-up vibration signal. On the other hand, stress concentration on the edge overflow can easily lead to crack propagation and premature crack aging of the coupling agent layer 7. In addition, the coupling agent layer 7 forms a water absorption channel and water storage space with the bedrock 1 and the vibration sensor 3, which has a significant impact on the aging rate of the coupling agent layer 7. The active knocking can be performed by hammering to confirm whether the vibration sensor 3 can clearly and stably capture this part of the artificial vibration signal, and by comparing the signal amplitude, waveform characteristics, and lack of low-frequency response with the expected signal pickup result, the signal coupling performance of the coupling agent layer 7 and the performance of the vibration sensor 3 itself are detected. The set time knocking is to regularly verify the pickup performance of the vibration signal, and the knocking after experiencing extreme weather is to verify the pickup performance of the vibration signal in an extreme environment.

[0130] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific embodiments of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art to which the present invention belongs, other embodiments derived without departing from the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. A monitoring system for rock collapse geological disasters on mountain slopes, which monitors rock collapse geological disasters on the bedrock (1) based on vibration signals on the bedrock (1) picked up by a vibration sensor (3), and is characterized in that: In the system, the vibration sensor (3) is fixed to the bedrock (1) via an anchor rod (2) installed in an anchor hole (14); a signal pickup surface of the vibration sensor (3) is in contact with the surface of the bedrock (1); and a coupling agent layer (7) is provided between the signal pickup surface and the surface. A plurality of drainage holes (16) are provided on the bedrock (1) and are located outside the signal pickup surface and surround the signal pickup surface; A step hole (13) is provided on the bedrock (1), and the anchor hole (14) is a hole section inside the step hole (13): the opening of the anchor hole (14) is located on the step surface of the step hole (13); A fitting surface (15) for coupling with a vibration sensor (3) is provided on the step surface, and the fitting surface (15) is a plane; The openings of the drainage holes (16) are all located on the step surface; The axis of the drainage hole (16) is distributed on a cylindrical surface, and the axis of the cylindrical surface is coaxial with the axis of the anchor hole (14); The number of the cylindrical surfaces is greater than 1, and each cylindrical surface is provided with a plurality of drainage holes (16) arranged in an annular manner; The anchor rod (2) is anchored in the anchor hole (14) through the anchoring adhesive layer (6); The head end of the anchor rod (2) extends out relative to the anchor hole (14), and a sliding sleeve (11) is provided on the head end and is slidably connected to the anchor rod (2). A pressure plate (8) is provided on one end of the sliding sleeve (11) close to the bedrock (1), and a vibration sensor (3) is connected to the side of the pressure plate (8) close to the bedrock (1) via a connecting bolt (10); It also includes a pressure cap (12) threadedly connected to the anchor rod (2), the pressure cap (12) applies a thrust force to the sliding sleeve (11) to image the bedrock (1), so that the vibration sensor (3) is clamped between the bedrock (1) and the pressure plate (8); The anchor rod (2) is provided with a guide groove (9) parallel to the axis of the anchor rod (2), and the inner side of the sliding sleeve (11) is provided with a guide edge, and the guide edge is embedded in the guide groove (9); Using a metal mesh to cover the opening of the drainage hole (16); The drainage hole (16) is an inclined hole inclined relative to the anchor hole (14), and specifically: the opening of the drainage hole (16) is relative to the hole bottom, and the distance between the opening and the anchor hole (14) is greater than the distance between the hole bottom and the anchor hole (14).

2. A mountain slope rock collapse geological disaster monitoring system according to claim 1, characterized in that: The number of vibration sensors (3) between the bedrock (1) and the pressure plate (8) is greater than or equal to 2.

3. A mountain slope rock collapse geological disaster monitoring system according to claim 1, characterized in that: Also included is a protective cover mounted on the bedrock (1) via an anchor (17), the protective cover comprising a breathable cover (5) fixed to the anchor (17); It also includes a flexible sheet (4), the inner end of the flexible sheet (4) is fixed to the anchor (17) and / or the bedrock (1), the outer end of the flexible sheet (4) is fixed to the breathable cover (5), and the flexible sheet (4) is used to block the gap between the breathable cover (5) and the bedrock (1); The vibration sensor (3) and the anchor rod (2) are both covered in a housing structure formed by a breathable cover (5) and a flexible sheet (4).

4. A mountain slope rock collapse geological disaster monitoring system according to claim 1, characterized in that: The distance between the drainage hole (16) and the vibration sensor (3) is 15 cm to 30 cm, the diameter of the drainage hole (16) is 4 mm to 6 mm, and the length of the drainage hole (16) is 8 cm to 15 cm.

5. A method for monitoring geological disasters of rock collapse on mountain slopes, characterized in that: The method uses the monitoring system described in any one of claims 1 to 4 to realize rock collapse geological disaster monitoring on bedrock (1), and the vibration sensor (3) picks up vibration signals with a frequency lower than 200 Hz.

6. A method for monitoring geological disasters of rock collapse on mountain slopes according to claim 5, characterized in that: The anchor rod (2) is anchored in the anchor hole (14) through an anchoring adhesive layer (6) of epoxy resin composite material filled with steel grit; The epoxy resin composite material is injected into the anchor hole (14) by a vacuum negative pressure grouting method, and the anchor rod (2) is anchored by: closing the anchor hole (14) and vacuuming and exhausting the anchor hole (14); injecting the epoxy resin composite material into the vacuumed and exhausted anchor hole (14); and inserting the anchor rod (2) into the epoxy resin composite material in the anchor hole (14).

7. A method for monitoring geological disasters of rock collapse on mountain slopes according to claim 5, characterized in that: The method for setting the drainage hole (16) and the vibration sensor (3) is as follows: Confirming the signal source position of the vibration signal on the bedrock (1) and the fitting position of the vibration sensor (3) on the bedrock (1); According to the signal source position and the fitting position, the drainage hole (16) is arranged on a side of the fitting position away from the signal source position; The vibration sensor (3) is installed after the drainage hole (16) is processed. The vibration sensor (3) is installed as follows: Evenly applying the coupling agent forming the coupling agent layer (7) on the signal pickup surface of the vibration sensor (3); Pressing the vibration sensor (3) toward the bedrock (1) and providing a pushing force of a set threshold value to the vibration sensor (3) through the anchor rod (2); Scrape off the coupling agent overflow around the vibration sensor (3) and outside the signal pickup surface under the pushing; During the process of the monitoring system performing geological disaster monitoring, the pickup quality of the vibration signal is tested by actively knocking the bedrock (1), wherein the active knocking includes active knocking under a set time plan and / or active knocking after experiencing extreme weather.

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