A soil slope internal moisture field distribution monitoring system and a monitoring method

Abstract

The application discloses a kind of soil slope internal moisture field distribution monitoring system and monitoring method, belong to slope instability monitoring field, including being arranged in the three-dimensional distributed monitoring network of the soil layer of slope to be monitored, field integrated monitoring mechanism and remote monitoring terminal, wherein three-dimensional distributed monitoring network is by embedding in the soil layer of the multiple longitudinal positions of slope to be monitored horizontal spiral temperature and humidity cable and along the lateral position of slope evenly arranged vertical temperature and humidity cable, horizontal spiral temperature and humidity cable and vertical temperature and humidity cable are connected with field integrated monitoring mechanism through optical cable interface, field integrated monitoring mechanism is communicated with remote monitoring terminal.Such soil slope internal moisture field distribution monitoring system and monitoring method, through the combination of sensing technology and integrated design, realize the global collection of slope soil layer moisture data, real-time transmission, intelligent analysis and abnormal early warning.

Description

Technical Field

[0001] This invention relates to the field of slope instability monitoring technology, and in particular to a monitoring system and method for monitoring the distribution of moisture field inside a soil slope. Background Technology

[0002] Slope instability is a major safety hazard commonly found in the construction of highways, railways, water conservancy projects, and mines. The dynamic changes in soil moisture content are one of the core driving factors that induce slope landslides and collapses. The infiltration and accumulation of water directly change the physical and mechanical properties of the soil (such as reduced shear strength and increased soil weight), thereby disrupting the stability balance of the slope.

[0003] Currently, traditional slope moisture monitoring methods mainly rely on the deployment of distributed soil moisture sensors or regular manual sampling, which has significant technical shortcomings: First, distributed sensors can only acquire discrete data from a single monitoring point, making it difficult to characterize the overall spatial distribution of the slope soil moisture field, easily creating monitoring blind spots, and failing to fully reflect the infiltration paths and enrichment patterns of water in the horizontal, vertical, and deep layers of the slope. Second, data transmission and response lack real-time performance, manual sampling suffers from long cycles, low efficiency, and strong subjectivity, and distributed sensors are mostly in offline data reading mode. When sudden abnormal changes occur in soil moisture, it is difficult to quickly trigger an early warning response, easily missing the golden window for risk management.

[0004] The core principle of fiber optic array monitoring technology is based on the sensing characteristics of fiber optic gratings. It continuously senses and transmits signals to surrounding parameters (such as temperature, humidity, and strain) along the fiber optic cable's deployment path, thereby accurately acquiring the spatially distributed information and temporal dynamic changes of these parameters. This technology has been applied in scenarios such as slope deformation monitoring, enabling real-time, high-precision monitoring of physical quantities such as slope displacement. However, for the need for three-dimensional distributed real-time monitoring of slope soil moisture fields, there is currently a lack of mature, integrated, and practical technical devices. Existing research mostly focuses on single-dimensional moisture monitoring and has not yet formed an integrated solution that considers full-area coverage, real-time transmission, and data fusion analysis. Related application research is still in a weak stage and cannot meet the actual needs of engineering practice for accurate monitoring and risk warning of slope moisture fields. Summary of the Invention

[0005] The purpose of this invention is to provide a monitoring system and method for monitoring the distribution of moisture field inside soil slopes, thereby solving the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides a soil slope internal moisture field distribution monitoring system, comprising a three-dimensional distributed monitoring network arranged inside the soil layer of the slope to be monitored, an integrated on-site monitoring mechanism, and a remote monitoring terminal. The three-dimensional distributed monitoring network consists of horizontal spiral temperature and humidity cables buried at multiple longitudinal positions inside the soil layer of the slope to be monitored and vertical temperature and humidity cables evenly arranged along the transverse position of the slope. Both the horizontal spiral temperature and humidity cables and the vertical temperature and humidity cables are connected to the integrated on-site monitoring mechanism via optical fiber interfaces. The integrated on-site monitoring mechanism communicates with the remote monitoring terminal.

[0007] Preferably, both the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable include a braided mesh, a spiral armored tube, and temperature and humidity optical fibers arranged sequentially from the outside to the inside. The temperature and humidity optical fibers include a temperature fiber grating array and a humidity fiber grating array. Kevlar fibers are filled between the temperature fiber grating array and the humidity fiber grating array, between the temperature fiber grating array and the spiral armored tube, and between the humidity fiber grating array and the spiral armored tube.

[0008] Preferably, the temperature fiber grating array operates at a wavelength of 1525nm-1565nm, the humidity fiber grating array operates at a wavelength of 1570nm-1610nm, the outer diameter of both the temperature and humidity fiber grating arrays is 6mm, and the distance between the temperature and humidity fiber grating arrays is 2mm. The spiral armored tube is made of SUS204 stainless steel; The woven mesh is made of SUS304 stainless steel with a mesh count of 80.

[0009] Preferably, the on-site integrated monitoring mechanism includes a housing, a foldable photovoltaic module installed on the outside of the housing, and a power supply module, an optical fiber demodulation module, an optical data processing module, and a signal transmission module fixed inside the housing. The foldable photovoltaic module is electrically connected to the power supply module, and the foldable photovoltaic module and the power supply module are electrically connected to the optical fiber demodulation module, the optical data processing module, and the signal transmission module, respectively. The fiber optic demodulation module is used to convert the optical signals collected by the temperature and humidity fiber optic cable into digital electrical signals and transmit them to the optical data processing module. The optical data processing module is used to smooth and denoise the received digital electrical signals, generate soil temperature and humidity wavelength data containing spatial location information, compare it with a preset threshold, and determine whether the data is abnormal and the level of abnormality based on the comparison results. The signal transmission module is used to transmit the judgment results of the optical data processing module to the remote monitoring terminal. The folded photovoltaic module charges the 12V / 100Ah lithium battery pack of the power supply module through a PWM-type charging controller.

[0010] Preferably, the foldable photovoltaic module includes a rotating opening and closing unit disposed on the housing and a photovoltaic panel unit disposed on the rotating opening and closing unit; wherein the rotating opening and closing unit includes four supports fixed to the top of the housing and arranged in a rectangular array, each of the four supports having a support rod hinged to its top, the top of the support rod being hinged to the bottom of the photovoltaic panel unit, and the support rod being positioned and connected to the support by a locking pin; two support rods arranged along the opening and closing direction are hinged together by a connecting rod. The photovoltaic panel unit consists of multiple photovoltaic panels that are linearly arrayed and hinged together. Adjacent photovoltaic panels are rotatably connected by a rotating shaft and a damping bearing, with a rotation angle of 0°-180°.

[0011] Preferably, the fiber demodulation module uses a distributed fiber grating demodulator with a wavelength resolution ≤1pm; The data processing module uses an ARM Cortex-A9 processor with a built-in 16GB data memory; The signal transmission module adopts a combination structure of a 4G / 5G dual-mode communication module and a Beidou satellite communication module; The signal input end of the fiber optic demodulation module is connected to the temperature and humidity fiber optic cable via an FC / APC connector, and the signal output end is electrically connected to the data processing module via an RS485 interface. The data processing module is connected to the signal transmission module via an SPI interface.

[0012] Preferably, the remote monitoring terminal includes a data processing and storage module, a data transmission module, a multi-screen display module, and an early warning module. The input end of the data processing and storage module communicates with the signal transmission module through the data transmission module, and the output end of the data processing and storage module is connected to the multi-screen display module and the early warning module, respectively. The data processing and storage module is used to generate a three-dimensional map of the soil moisture field distribution on the slope based on the received soil temperature, humidity and wavelength data and the preliminary judgment results. The multi-screen display module is used to generate temperature and humidity data, trend curves, and thermal maps of moisture field distribution at each monitoring point in real time based on the three-dimensional map of the moisture field distribution of the slope soil layer. The early warning module is used to issue an early warning when the moisture data at a certain monitoring point exceeds a preset threshold.

[0013] A monitoring method for a soil slope internal moisture field distribution monitoring system includes the following steps: S1. The three-dimensional distributed monitoring network is deployed according to the preset monitoring range, and the combination of horizontal spiral temperature and humidity cables and vertical temperature and humidity cables is completed in the soil layer of the slope to be monitored. S11. Horizontal spiral temperature and humidity cables are laid along the slope in a spiral manner to ensure full lateral coverage of the slope. S12, Vertical direction: Drill holes every 10 meters along the slope to form monitoring holes. The diameter of the monitoring holes is 5cm. The drilling depth extends to 2-3 meters below the bedrock of the slope. Extend the vertical temperature and humidity cable from the bottom of the hole to the opening of the hole to complete the layout of deep moisture monitoring points on the slope. S13. Cable connection: Connect one end of all horizontal spiral temperature and humidity cables and one end of vertical temperature and humidity cables to the optical cable interface of the integrated on-site monitoring agency through a sealed joint to form a blind-spot-free three-dimensional monitoring network. S2. Unfold the foldable photovoltaic module on the top of the integrated on-site monitoring unit, and charge the 12V / 100Ah lithium battery pack of the power supply module through the PWM type charging controller; the power supply module supplies power to the fiber demodulation module, optical data processing module and signal transmission module through the power manager; S3, the temperature fiber optic grating array and humidity fiber optic grating array in the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable sense the temperature and humidity information at different locations and depths of the slope in real time, and transmit it to the fiber demodulation module in the form of optical signals; the fiber demodulation module receives the optical signals through the FC / APC connector, converts them into digital electrical signals, and then transmits them to the optical data processing module through the RS485 interface. S4, the optical data processing module performs smoothing and noise reduction preprocessing on the received digital electrical signal, and generates soil temperature, humidity and wavelength data containing spatial location information by combining the three-dimensional coordinate data of each grid point on the slope; and calls the built-in preset threshold to compare the preprocessed data with the preset threshold to determine whether the data is abnormal and the level of abnormality. S5. The signal transmission module receives the judgment result of the optical data processing module and the original soil temperature, humidity and wavelength data through the SPI interface, and transmits the data to the remote monitoring terminal using the TCP / IP protocol. S6. After receiving the data transmitted from the field, the data transmission module of the remote monitoring terminal sends it to the data processing and storage module. The data processing and storage module performs in-depth analysis on the data, generates a three-dimensional map of the slope soil moisture field distribution, and transmits it to the multi-screen display module. Based on the three-dimensional map of the slope soil moisture field distribution, the multi-screen display module displays the temperature and humidity data, trend curves, and moisture field distribution heat map of each monitoring point in real time, allowing managers to intuitively grasp the slope moisture field status. S7. The early warning module reads the analysis results from the data processing and storage module in real time. When the moisture data at the monitoring point reaches 80% of the preset early warning threshold, a yellow early warning is activated; when the data reaches 100% of the preset early warning threshold, a red early warning is activated. At the same time, the early warning module issues early warning reminders through three methods: pop-up alerts, SMS notifications, and voice broadcasts.

[0014] Preferably, in step S5, 5G communication, 4G communication and BeiDou satellite communication are switched sequentially according to priority based on the strength of the on-site communication signal. If BeiDou satellite communication cannot meet the set requirements, an alarm is triggered.

[0015] Preferably, step S6 specifically includes the following steps: S61. The data transmitted in the field is denoised using the 3σ criterion, and then the moisture content is inverted. The inversion expression is as follows: ; In the formula, This indicates the volumetric water content of the slope soil layer; The moisture sensitivity coefficient of the fiber Bragg grating array represents the humidity. This represents the wavelength offset of the original optical signal; Indicates the calibration constant; S62. Based on the layout rules of the horizontal and vertical spiral temperature and humidity cables of the three-dimensional distributed monitoring network, obtain the spatial location of the grid points. Among them, the three-dimensional coordinates of the grid points of the horizontal spiral temperature and humidity cable The expression is as follows: ; Three-dimensional coordinates of grid points in vertical temperature and humidity cable The expression is as follows: ; In the formula, Indicates the coordinates of the starting point for laying the horizontal spiral temperature and humidity cable; Indicates the grid point number on the horizontal spiral temperature and humidity cable; This indicates the spacing between two adjacent grid points on a horizontal spiral temperature and humidity cable. and These represent the laying direction angle and inclination angle of the horizontal spiral temperature and humidity cable, respectively. Indicates the coordinates of the starting point for laying the vertical temperature and humidity cable; Indicates the grid point number on the vertical temperature and humidity cable; Indicates the azimuth angle of the vertical borehole; S63. Construct a grid point spatial mapping adapted to a depth of 1m-20.0m and a monitoring range of 10km; S64. Based on the spatial correlation of soil moisture, the measured values ​​of discrete grid points are used as hard data through the co-kriging interpolation algorithm. Spatial parameters are fitted by the semi-variogram function to estimate the moisture value of unmeasured points, thus completing the transformation from linear grid points to a three-dimensional continuous moisture field. S65. Spatial registration of the three-dimensional continuous water field with the slope topography model, and generation of a three-dimensional map through visualization rendering.

[0016] Therefore, the beneficial effects of the above-mentioned soil slope internal moisture field distribution monitoring system and method are as follows: 1. Improved monitoring range and accuracy: Using dual-core distributed temperature and humidity optical fiber, a three-dimensional monitoring network is formed through a combination of horizontal and vertical deployment, covering the slope depth range of [1m-20.0m] and a monitoring range of 10km in length, avoiding monitoring blind spots, with temperature measurement accuracy of ±1℃ and humidity measurement accuracy of ±5%RH, significantly improving the spatial integrity of data and monitoring accuracy. 2. High integration and environmental adaptability: The core equipment such as the fiber optic demodulation module and data processing module are integrated into an IP67-rated sealed waterproof enclosure, and equipped with corrosion-resistant and wear-resistant armored optical cables. It can withstand harsh outdoor environments such as rainstorms, high temperatures, and sandstorms, reduce environmental interference, and extend the service life of the device to more than 5 years. 3. Stable battery life and transmission: It adopts a dual power supply mode of "solar + lithium battery", eliminating the need for an external power cord. It can meet the long-term field monitoring needs in remote areas and can maintain uninterrupted operation for 7 days in continuous rainy weather on a single charge. The 4G / 5G and Beidou dual-mode communication design solves the data transmission problem in mountainous areas and other areas with weak signals, with a transmission delay of ≤10s. 4. Timely and efficient early warning: Early warning is issued through multiple methods via the terminal platform. The response time from data anomaly to issuing an early warning is ≤30 seconds, which provides sufficient time for slope safety treatment and reduces the losses from landslide accidents. 5. Convenient deployment and maintenance: The integrated design reduces on-site installation steps, shortening deployment time by 50% compared to traditional monitoring systems. Solar power reduces maintenance frequency, requiring only quarterly equipment inspections, reducing maintenance costs by 60%. 6. Improved cost-effectiveness: High integration and low maintenance costs after one-time deployment. In the long run, it has higher cost-effectiveness compared to traditional multi-point sensor networks.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] Figure 1 This is a structural block diagram of a soil slope internal moisture field distribution monitoring system according to the present invention; Figure 2 This is a three-dimensional distributed monitoring network layout diagram of a soil slope internal moisture field distribution monitoring system according to the present invention, wherein (a) is a longitudinal layout diagram, (b) is a transverse layout diagram, and (c) is a schematic diagram of monitoring holes. Figure 3 This is a radial cross-sectional view of the temperature and humidity cable of a soil slope internal moisture field distribution monitoring system according to the present invention. Figure 4This is a diagram showing the folded photovoltaic module of the integrated field monitoring mechanism of the soil slope internal moisture field distribution monitoring system described in this invention, in its folded state. Figure 5 This is a diagram showing the unfolded shape of the folded photovoltaic module of the integrated monitoring mechanism for the soil slope internal moisture field distribution monitoring system described in this invention.

[0019] Figure Labels 1. Housing; 2. Folded photovoltaic module; 21. Support; 22. Support rod; 23. Connecting rod; 24. Photovoltaic panel unit; 25. Locking pin; 3. FC / APC connector; 4. Temperature and humidity optical fiber; 5. Spiral armored tube; 6. Braided mesh; 7. Kevlar fiber. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0021] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0022] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0023] like Figures 1-5 As shown, a soil slope internal moisture field distribution monitoring system includes a three-dimensional distributed monitoring network arranged inside the soil layer of the slope to be monitored, an integrated on-site monitoring mechanism, and a remote monitoring terminal. The three-dimensional distributed monitoring network consists of horizontal spiral temperature and humidity cables buried at multiple longitudinal positions inside the soil layer of the slope to be monitored and vertical temperature and humidity cables evenly arranged along the transverse position of the slope. Both the horizontal spiral temperature and humidity cables and the vertical temperature and humidity cables are connected to the integrated on-site monitoring mechanism via optical fiber interfaces. The integrated on-site monitoring mechanism communicates with the remote monitoring terminal.

[0024] Both the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable include a braided mesh 6, a spiral armored tube 5, and a temperature and humidity optical fiber 4 arranged sequentially from the outside to the inside. The temperature and humidity optical fiber 4 includes a temperature fiber grating array and a humidity fiber grating array. Kevlar fibers 7 are filled between the temperature fiber grating array and the humidity fiber grating array, between the temperature fiber grating array and the spiral armored tube 5, and between the humidity fiber grating array and the spiral armored tube 5.

[0025] The temperature fiber Bragg grating array operates at a wavelength of 1525nm-1565nm, and the humidity fiber Bragg grating array operates at a wavelength of 1570nm-1610nm. The outer diameter of both the temperature and humidity fiber Bragg grating arrays is 6mm, and the distance between them is 2mm. The spiral armored tube 5 is made of SUS204 stainless steel, and the braided mesh 6 is made of SUS304 stainless steel with a mesh count of 80.

[0026] The on-site integrated monitoring mechanism includes a housing 1, a folded photovoltaic module 2 installed on the outside of the housing 1, and a power supply module, an optical fiber demodulation module, an optical data processing module, and a signal transmission module fixed inside the housing 1. The folded photovoltaic module 2 is electrically connected to the power supply module, and the folded photovoltaic module 2 and the power supply module are electrically connected to the optical fiber demodulation module, the optical data processing module, and the signal transmission module, respectively. The fiber optic demodulation module is used to convert the optical signal collected by the temperature and humidity fiber optic cable 4 into a digital electrical signal and transmit it to the optical data processing module. The optical data processing module is used to smooth and denoise the received digital electrical signals, generate soil temperature and humidity wavelength data containing spatial location information, compare it with a preset threshold, and determine whether the data is abnormal and the level of abnormality based on the comparison results. The signal transmission module is used to transmit the judgment results of the optical data processing module to the remote monitoring terminal. The folded photovoltaic module 2 charges the 12V / 100Ah lithium battery pack of the power supply module through a PWM type charging controller.

[0027] The foldable photovoltaic module 2 includes a rotating opening and closing unit mounted on a housing 1 and photovoltaic panel units 24 mounted on the rotating opening and closing unit. The rotating opening and closing unit includes four supports 21 fixed to the top of the housing 1 and arranged in a rectangular array. Each of the four supports 21 has a support rod 22 hinged to its top. The top of the support rod 22 is hinged to the bottom of the photovoltaic panel unit, and the support rod 22 is also positioned and connected to the support 21 via a locking pin 25. Two support rods 22 arranged along the opening and closing direction are hinged together by a connecting rod. The photovoltaic panel unit includes multiple photovoltaic panels arranged in a linear array and hinged together. Adjacent photovoltaic panels are rotatably connected via a rotating shaft and a damping bearing, with a rotation angle of 0°-180°. Using the above method, when the foldable photovoltaic module is unfolded, simply pull out the locking pin, pull the edge photovoltaic panels outwards to unfold it, and push the edge photovoltaic panels inwards and reinsert the locking pin to retract it.

[0028] The fiber optic demodulation module uses a distributed fiber Bragg grating demodulator with a wavelength resolution ≤1pm; the data processing module uses an ARM Cortex-A9 processor with a built-in 16GB data memory; the signal transmission module adopts a combination structure of a 4G / 5G dual-mode communication module and a Beidou satellite communication module; the signal input end of the fiber optic demodulation module is connected to the temperature and humidity fiber optic cable 4 through FC / APC connector 3, and the signal output end is electrically connected to the data processing module through an RS485 interface. The data processing module is connected to the signal transmission module through an SPI interface.

[0029] The remote monitoring terminal includes a data processing and storage module, a data transmission module, a multi-screen display module, and an early warning module. The input end of the data processing and storage module communicates with the signal transmission module through the data transmission module, and the output end of the data processing and storage module is connected to the multi-screen display module and the early warning module, respectively. The data processing and storage module is used to generate a three-dimensional map of the soil moisture field distribution on the slope based on the received soil temperature, humidity and wavelength data and the preliminary judgment results. The multi-screen display module is used to generate temperature and humidity data, trend curves and thermal maps of moisture field distribution at each monitoring point in real time based on the three-dimensional map of moisture field distribution in the slope soil layer. The early warning module is used to issue an early warning when the moisture data at a certain monitoring point exceeds a preset threshold.

[0030] A monitoring method for a soil slope internal moisture field distribution monitoring system includes the following steps: S1. The three-dimensional distributed monitoring network is deployed according to the preset monitoring range, and the combination of horizontal spiral temperature and humidity cables and vertical temperature and humidity cables is completed in the soil layer of the slope to be monitored. S11. Horizontal spiral temperature and humidity cables are laid out in a spiral manner along the slope to ensure full lateral coverage of the slope. In this embodiment, the horizontal spiral temperature and humidity cable can be laid out as a single cable or can share the same cable with the vertically laid cable. S12, Vertical direction: Drill monitoring holes every 10 meters along the slope. The diameter of the monitoring holes is 5 cm. The drilling depth extends 2-3 meters below the bedrock of the slope. Extend the vertical temperature and humidity cable from the bottom of the hole to the opening of the hole to complete the layout of deep moisture monitoring points on the slope. Similarly, in this embodiment, a single cable can be used to pass through all the monitoring holes and cover the monitoring range by serpentine arrangement. Alternatively, when there are fewer monitoring holes, a cable can be laid in each hole. S13. Cable connection: Connect one end of all horizontal spiral temperature and humidity cables and one end of vertical temperature and humidity cables to the optical cable interface of the integrated on-site monitoring agency through a sealed joint to form a blind-spot-free three-dimensional monitoring network. S2. Unfold the folded photovoltaic module 2 on the top of the integrated on-site monitoring mechanism box 1, and charge the 12V / 100Ah lithium battery pack of the power supply module through the PWM type charging controller; the power supply module supplies power to the fiber demodulation module, optical data processing module and signal transmission module respectively through the power manager; S3, the temperature fiber optic grating array and humidity fiber optic grating array in the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable sense the temperature and humidity information at different locations and depths of the slope in real time, and transmit it to the fiber demodulation module in the form of optical signals; the fiber demodulation module receives the optical signals through FC / APC connector 3, converts them into digital electrical signals, and then transmits them to the optical data processing module through RS485 interface. S4, the optical data processing module performs smoothing and noise reduction preprocessing on the received digital electrical signal, and generates soil temperature, humidity and wavelength data containing spatial location information by combining the three-dimensional coordinate data of each grid point on the slope; and calls the built-in preset threshold to compare the preprocessed data with the preset threshold to determine whether the data is abnormal and the level of abnormality. S5. The signal transmission module receives the judgment result of the optical data processing module and the original soil temperature, humidity and wavelength data through the SPI interface, and transmits the data to the remote monitoring terminal using the TCP / IP protocol. S6. After receiving the data transmitted from the field, the data transmission module of the remote monitoring terminal sends it to the data processing and storage module. The data processing and storage module performs in-depth analysis on the data, generates a three-dimensional map of the slope soil moisture field distribution, and transmits it to the multi-screen display module. Based on the three-dimensional map of the slope soil moisture field distribution, the multi-screen display module displays the temperature and humidity data, trend curves, and moisture field distribution heat map of each monitoring point in real time, allowing managers to intuitively grasp the slope moisture field status. S7. The early warning module reads the analysis results from the data processing and storage module in real time. When the moisture data at the monitoring point reaches 80% of the preset early warning threshold, a yellow early warning is activated; when the data reaches 100% of the preset early warning threshold, a red early warning is activated. At the same time, the early warning module issues early warning reminders through three methods: pop-up alerts, SMS notifications, and voice broadcasts.

[0031] In step S5, based on the strength of the on-site communication signal, 5G communication is switched sequentially to 4G communication and then to BeiDou satellite communication according to priority. If BeiDou satellite communication cannot meet the set requirements, an alarm is triggered. In this embodiment, hysteresis control is used during the operation phase to avoid erroneous switching: cellular to BeiDou requires that the 5G signal RSRP < -120dBm and the 4G signal RSSI < -95dBm (lasting 10 seconds), and that BeiDou is available. During the switch, data is cached, the cellular link is disconnected, BeiDou narrowband format transmission is adapted, and the status is reported. BeiDou to cellular mode requires that the 5G / 4G signal meets the standard (lasting 15 seconds), and cellular registration is successful. After the switch, data is cached synchronously and the system switches back to cellular mode. 5G and 4G switching is seamless, with a stable 5-second trigger time and a switching time of ≤2 seconds, ensuring real-time performance. Furthermore, if the cellular module fails to start, it automatically retryes 3 times (with a 3-second interval). If it fails, it switches to the next priority. If there are no available BeiDou satellites, it continuously scans for 5 minutes (retrying every 30 seconds). If it fails, an alarm is maintained and the cellular signal is monitored. Meanwhile, data is transmitted in a priority-based manner, with high-risk data being sent in queue and regular data being compressed / uploaded in batches as needed. In terms of power consumption, low-frequency monitoring (every 5 seconds) is used when the cellular signal is stable, and high-frequency monitoring (every 1 second) is used when the signal is unstable. In BeiDou mode, the system goes into standby mode after transmitting data, adapting to outdoor solar power supply requirements.

[0032] Step S6 specifically includes the following steps: S61. The data transmitted in the field is denoised using the 3σ criterion, and then the moisture content is inverted. The inversion expression is as follows: ; In the formula, This indicates the volumetric water content of the slope soil layer; The moisture sensitivity coefficient of the fiber Bragg grating array represents the humidity. This represents the wavelength offset of the original optical signal; Indicates the calibration constant; S62. Based on the layout rules of the horizontal and vertical spiral temperature and humidity cables of the three-dimensional distributed monitoring network, obtain the spatial location of the grid points. Among them, the three-dimensional coordinates of the grid points of the horizontal spiral temperature and humidity cable The expression is as follows: ; Three-dimensional coordinates of grid points in vertical temperature and humidity cable The expression is as follows: ; In the formula, Indicates the coordinates of the starting point for laying the horizontal spiral temperature and humidity cable; Indicates the grid point number on the horizontal spiral temperature and humidity cable; This indicates the spacing between two adjacent grid points on a horizontal spiral temperature and humidity cable. and These represent the laying direction angle and inclination angle of the horizontal spiral temperature and humidity cable, respectively. Indicates the coordinates of the starting point for laying the vertical temperature and humidity cable; Indicates the grid point number on the vertical temperature and humidity cable; Indicates the azimuth angle of the vertical borehole; S63. Construct a grid point spatial mapping adapted to a depth of 1m-20.0m and a monitoring range of 10km; S64. Based on the spatial correlation of soil moisture, the measured values ​​of discrete grid points are used as hard data through the co-kriging interpolation algorithm. Spatial parameters are fitted by the semi-variogram function to estimate the moisture value of unmeasured points, thus completing the transformation from linear grid points to a three-dimensional continuous moisture field. S65. Spatial registration of the three-dimensional continuous water field with the slope topography model, and generation of a three-dimensional map through visualization rendering.

[0033] By deploying and accurately reconstructing horizontal and vertical temperature and humidity cables in three dimensions, the accuracy of moisture field characterization in wide-range, deep-coverage scenarios is significantly improved, adapting to the large-scale monitoring needs of mountain slopes.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A system for monitoring the distribution of moisture field inside a soil slope, characterized in that: It includes a three-dimensional distributed monitoring network deployed inside the soil layer of the slope to be monitored, an integrated on-site monitoring mechanism, and a remote monitoring terminal. The three-dimensional distributed monitoring network consists of horizontal spiral temperature and humidity cables buried at multiple longitudinal positions inside the soil layer of the slope to be monitored and vertical temperature and humidity cables evenly distributed along the transverse position of the slope. Both the horizontal spiral temperature and humidity cables and the vertical temperature and humidity cables are connected to the integrated on-site monitoring mechanism via optical cable interfaces. The integrated on-site monitoring mechanism communicates with the remote monitoring terminal. A monitoring method for a soil slope internal moisture field distribution monitoring system includes the following steps: S1. The three-dimensional distributed monitoring network is deployed according to the preset monitoring range, and the combination of horizontal spiral temperature and humidity cables and vertical temperature and humidity cables is completed in the soil layer of the slope to be monitored. S11. Horizontal spiral temperature and humidity cables are laid along the slope in a spiral manner to ensure full lateral coverage of the slope. S12, Vertical direction: Drill holes every 10 meters along the slope to form monitoring holes. The diameter of the monitoring holes is 5cm. The drilling depth extends to 2-3 meters below the bedrock of the slope. Extend the vertical temperature and humidity cable from the bottom of the hole to the opening of the hole to complete the layout of deep moisture monitoring points on the slope. S13. Cable connection: Connect one end of all horizontal spiral temperature and humidity cables and one end of vertical temperature and humidity cables to the optical cable interface of the integrated on-site monitoring agency through a sealed joint to form a blind-spot-free three-dimensional monitoring network. S2. Unfold the foldable photovoltaic module on the top of the integrated on-site monitoring unit, and charge the 12V / 100Ah lithium battery pack of the power supply module through the PWM type charging controller; the power supply module supplies power to the fiber demodulation module, optical data processing module and signal transmission module through the power manager; S3, the temperature fiber optic grating array and humidity fiber optic grating array in the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable sense the temperature and humidity information at different locations and depths of the slope in real time, and transmit it to the fiber demodulation module in the form of optical signals; the fiber demodulation module receives the optical signals through the FC / APC connector, converts them into digital electrical signals, and then transmits them to the optical data processing module through the RS485 interface. S4, the optical data processing module performs smoothing and noise reduction preprocessing on the received digital electrical signal, and generates soil temperature, humidity and wavelength data containing spatial location information by combining the three-dimensional coordinate data of each grid point on the slope; and calls the built-in preset threshold to compare the preprocessed data with the preset threshold to determine whether the data is abnormal and the level of abnormality. S5. The signal transmission module receives the judgment result of the optical data processing module and the original soil temperature, humidity and wavelength data through the SPI interface, and transmits the data to the remote monitoring terminal using the TCP / IP protocol. S6. After receiving the data transmitted from the field, the data transmission module of the remote monitoring terminal sends it to the data processing and storage module. The data processing and storage module performs in-depth analysis on the data, generates a three-dimensional map of the slope soil moisture field distribution, and transmits it to the multi-screen display module. Based on the three-dimensional map of the slope soil moisture field distribution, the multi-screen display module displays the temperature and humidity data, trend curves, and moisture field distribution heat map of each monitoring point in real time, allowing managers to intuitively grasp the slope moisture field status. S7. The early warning module reads the analysis results from the data processing and storage module in real time. When the moisture data at the monitoring point reaches 80% of the preset early warning threshold, a yellow warning is activated; when the data reaches 100% of the preset early warning threshold, a red warning is activated. At the same time, the early warning module issues early warning reminders through three methods: pop-up alerts, SMS notifications, and voice broadcasts. Step S6 specifically includes the following steps: S61. The data transmitted in the field is denoised using the 3σ criterion, and then the moisture content is inverted. The inversion expression is as follows: ； In the formula, This indicates the volumetric water content of the slope soil layer; The moisture sensitivity coefficient of the fiber Bragg grating array represents the humidity. This represents the wavelength offset of the original optical signal; Indicates the calibration constant; S62. Based on the layout rules of the horizontal spiral temperature and humidity cables and the vertical temperature and humidity cables of the three-dimensional distributed monitoring network, obtain the spatial location of the grid points. Among them, the three-dimensional coordinates of the grid points of the horizontal spiral temperature and humidity cable The expression is as follows: ； Three-dimensional coordinates of grid points in vertical temperature and humidity cable The expression is as follows: ； In the formula, Indicates the coordinates of the starting point for laying the horizontal spiral temperature and humidity cable; Indicates the grid point number on the horizontal spiral temperature and humidity cable; This indicates the spacing between two adjacent grid points on a horizontal spiral temperature and humidity cable. and These represent the laying direction angle and inclination angle of the horizontal spiral temperature and humidity cable, respectively. Indicates the coordinates of the starting point for laying the vertical temperature and humidity cable; Indicates the grid point number on the vertical temperature and humidity cable; Indicates the azimuth angle of the vertical borehole; S63. Construct a grid point spatial mapping adapted to a depth of 1m-20.0m and a monitoring range of 10km; S64. Based on the spatial correlation of soil moisture, the measured values ​​of discrete grid points are used as hard data through the co-kriging interpolation algorithm. Spatial parameters are fitted by the semi-variogram function to estimate the moisture value of unmeasured points, thus completing the transformation from linear grid points to a three-dimensional continuous moisture field. S65. Spatial registration of the three-dimensional continuous water field with the slope topography model, and generation of a three-dimensional map through visualization rendering.

2. The soil slope internal moisture field distribution monitoring system according to claim 1, characterized in that: Both the horizontal spiral temperature and humidity cable and the vertical temperature and humidity cable include a braided mesh, a spiral armored tube, and temperature and humidity optical fibers arranged sequentially from the outside to the inside. The temperature and humidity optical fibers include a temperature fiber grating array and a humidity fiber grating array. Kevlar fibers are filled between the temperature fiber grating array and the humidity fiber grating array, between the temperature fiber grating array and the spiral armored tube, and between the humidity fiber grating array and the spiral armored tube.

3. The soil slope internal moisture field distribution monitoring system according to claim 2, characterized in that: The temperature fiber grating array operates at a wavelength of 1525nm-1565nm, and the humidity fiber grating array operates at a wavelength of 1570nm-1610nm. The outer diameter of both the temperature and humidity fiber grating arrays is 6mm, and the distance between them is 2mm. The spiral armored tube is made of SUS204 stainless steel; The woven mesh is made of SUS304 stainless steel with a mesh count of 80.

4. A soil slope internal moisture field distribution monitoring system according to claim 3, characterized in that: The on-site integrated monitoring mechanism includes a housing, foldable photovoltaic modules installed on the outside of the housing, and a power supply module, an optical fiber demodulation module, an optical data processing module, and a signal transmission module fixed inside the housing. The foldable photovoltaic modules are electrically connected to the power supply module, and the foldable photovoltaic modules and the power supply module are electrically connected to the optical fiber demodulation module, the optical data processing module, and the signal transmission module, respectively. The fiber optic demodulation module is used to convert the optical signals collected by the temperature and humidity fiber optic cable into digital electrical signals and transmit them to the optical data processing module. The optical data processing module is used to smooth and denoise the received digital electrical signals, generate soil temperature and humidity wavelength data containing spatial location information, compare it with a preset threshold, and determine whether the data is abnormal and the level of abnormality based on the comparison results. The signal transmission module is used to transmit the judgment results of the optical data processing module to the remote monitoring terminal. The folded photovoltaic module charges the 12V / 100Ah lithium battery pack of the power supply module through a PWM-type charging controller.

5. A soil slope internal moisture field distribution monitoring system according to claim 4, characterized in that: The foldable photovoltaic module includes a rotating opening and closing unit mounted on a housing and a photovoltaic panel unit mounted on the rotating opening and closing unit. The rotating opening and closing unit includes four supports fixed to the top of the housing and arranged in a rectangular array. Each of the four supports has a support rod hinged to its top. The top of the support rod is hinged to the bottom of the photovoltaic panel unit, and the support rod and the support are also positioned and connected by a locking pin. Two support rods arranged along the opening and closing direction are hinged together by a connecting rod. The photovoltaic panel unit consists of multiple photovoltaic panels that are linearly arrayed and hinged together. Adjacent photovoltaic panels are rotatably connected by a rotating shaft and a damping bearing, with a rotation angle of 0°-180°.

6. A soil slope internal moisture field distribution monitoring system according to claim 5, characterized in that: The fiber demodulation module uses a distributed fiber grating demodulator with a wavelength resolution ≤1pm; The optical data processing module uses an ARM Cortex-A9 processor and has a built-in 16GB data storage. The signal transmission module adopts a combination structure of a 4G / 5G dual-mode communication module and a Beidou satellite communication module; The signal input end of the fiber optic demodulation module is connected to the temperature and humidity fiber optic cable via an FC / APC connector, and the signal output end is electrically connected to the optical data processing module via an RS485 interface. The optical data processing module is connected to the signal transmission module via an SPI interface.

7. A soil slope internal moisture field distribution monitoring system according to claim 6, characterized in that: The remote monitoring terminal includes a data processing and storage module, a data transmission module, a multi-screen display module, and an early warning module. The input end of the data processing and storage module communicates with the signal transmission module through the data transmission module, and the output end of the data processing and storage module is connected to the multi-screen display module and the early warning module, respectively. The data processing and storage module is used to generate a three-dimensional map of the soil moisture field distribution on the slope based on the received soil temperature, humidity and wavelength data and the preliminary judgment results. The multi-screen display module is used to generate temperature and humidity data, trend curves, and thermal maps of moisture field distribution at each monitoring point in real time based on the three-dimensional map of the moisture field distribution of the slope soil layer. The early warning module is used to issue an early warning when the moisture data at a certain monitoring point exceeds a preset threshold.

8. A soil slope internal moisture field distribution monitoring system according to claim 1, characterized in that: In step S5, 5G communication, 4G communication, and BeiDou satellite communication are switched sequentially according to priority based on the strength of the on-site communication signal. If BeiDou satellite communication cannot meet the set requirements, an alarm is triggered.

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