Deeply-buried rock-soil layer settlement monitoring device and settlement monitoring method

Abstract

The invention belongs to the technical field of geotechnical engineering, and particularly discloses a settlement monitoring device and a settlement monitoring method for a deeply-buried rock-soil layer. A transmitting coil and a receiving coil of the device are buried at the bottom and the upper part of a rock-soil layer to form a coaxial circular ring, and the vertical distance is the same as the thickness of the rock-soil layer; the receiving and transmitting coil is electrically connected with the signal receiving and transmitting device, and the signal receiving device is electrically connected with the server. The method comprises the following steps: determining the sizes of transmitting and receiving coils, the cross sectional area and the number of turns of enameled wires and power supply current; actually measuring the induced electromotive force of the transmitting coil and the receiving coil at different vertical intervals, and fitting the different intervals with the induced electromotive force to obtain a fitting function; the transmitting coil and the receiving coil are buried at the bottom and the upper part of a rock-soil layer to form coaxial rings, and the vertical distance is the same as the thickness of the rock-soil layer; and introducing power supply current, measuring the induced electromotive force of the receiving coil and substituting the induced electromotive force into the fitting function to obtain the thickness of the rock-soil layer. The device has the characteristics of simple structure, low cost, safety, reliability, simplicity and convenience in operation and high monitoring precision.

Description

Technical Field

[0001] The present invention belongs to the field of geotechnical engineering technology, and specifically relates to a deep-buried rock and soil layer settlement monitoring device and settlement monitoring method with simple structure, low cost, safety and reliability, easy operation and high monitoring accuracy. Background Art

[0002] With the continuous expansion of engineering construction and the increasing complexity of geological conditions, monitoring the settlement of deeply buried rock and soil layers and accurately grasping their settlement data can help analyze settlement patterns and promptly identify potential geological hazards. This not only helps optimize engineering design and construction plans to improve project quality and stability, but also allows for proactive measures to prevent geological disasters, reduce construction and operational risks, and avoid safety accidents such as building tilting, cracking, and even collapse caused by settlement. Therefore, monitoring the settlement of deeply buried rock and soil layers is of vital importance in engineering fields such as subway tunnel construction, high-rise building foundation stability assessment, and mineral resource mining subsidence control.

[0003] Currently, differential pressure levels and vibrating-wire soil settlement meters are commonly used to monitor geotechnical strata. Differential pressure levels utilize the principles of communicating vessels and the static equilibrium of liquids. When the liquid level at each measuring point experiences a height difference due to factors such as settlement, the pressure difference generated by the liquid column is measured to calculate the change in height between the two points, thereby determining the settlement at each measuring point. Vibrating-wire soil settlement meters, on the other hand, rely on the characteristic that the natural frequency of a vibrating wire changes with the stress it is subjected to. When soil settles, the sensitive element of the settlement meter deforms, which in turn changes the stress state of the vibrating wire. The amount of soil settlement is calculated by measuring the change in the frequency of the vibrating wire. However, both of these monitoring methods require the electronic equipment to be buried deep in the geotechnical strata. This not only makes instrument installation and maintenance difficult, but also, due to the relatively moist geotechnical strata, electronic components are susceptible to damage. Therefore, monitoring methods based on electronic readings are not suitable for use in deeply buried geotechnical strata.

[0004] In the existing technology, there are also layered settlement markers and electromagnetic settlement meters for monitoring rock and soil layers. Layered settlement marker monitoring involves drilling holes in the rock and soil layer and burying multiple layers of settlement markers. The settlement changes of the measured soil layer are brought to the ground through the markers to measure the settlement of the rock and soil layer. However, layered settlement markers require the markers to be connected to the ground section by section as the fill is constructed, and the settlement is observed using leveling methods, which makes settlement monitoring more cumbersome and cannot be achieved in real time. Moreover, the settlement markers are easily affected by the humid environment during the burial and measurement process, resulting in inaccurate measurement data or damage to the settlement markers, affecting the reliability of the monitoring results. Electromagnetic settlement meter monitoring involves burying a casing vertically inside the fill, setting a magnetic ring at a certain depth along the outside of the casing, and using an electromagnetic induction probe to determine the position of each magnetic ring. The settlement of different soil layers in the fill and the total settlement are then calculated based on the pipe mouth elevation. Since electromagnetic settlement meter monitoring requires manual measurement, the measurement results are affected by the measurement accuracy of the matching steel ruler and human errors. In addition, each measurement requires the use of leveling to calibrate the pipe mouth elevation, which increases the measurement workload and affects the measurement accuracy.

[0005] Therefore, studying a deep buried rock and soil layer settlement monitoring device and settlement monitoring method with simple structure, low cost, safety and reliability, easy operation and high monitoring accuracy has important practical significance for improving deep buried rock and soil layer settlement monitoring. Summary of the Invention

[0006] In order to solve the problems mentioned in the above background technology, the present invention provides a deep buried rock and soil layer settlement monitoring device with simple structure, low cost, safety and reliability, easy operation and high monitoring accuracy, and also provides a deep buried rock and soil layer settlement monitoring method.

[0007] The deep buried rock and soil layer settlement monitoring device of the present invention is implemented as follows: comprising a transmitting coil, a receiving coil, a signal transmitting device, a signal receiving device, and a server. The transmitting coil and the receiving coil are respectively buried at the bottom and the top of the monitored rock and soil layer to form a coaxial ring. The vertical distance between the transmitting coil and the receiving coil is equal to the thickness of the monitored rock and soil layer. d same; The receiving coil is electrically connected to a signal receiving device, the transmitting coil is electrically connected to a signal transmitting device, and the signal receiving device is electrically connected to a server.

[0008] Furthermore, the transmitting coil and the receiving coil have the same diameter and are circular rings of 0.8 to 1.5 m, and the ratio of the number of turns of the enameled wire of the transmitting coil to that of the receiving coil is 100:800 to 1500; the power supply current of the transmitting coil is based on the ability to effectively identify the signal in the receiving coil at the maximum spacing.

[0009] Furthermore, before burying the transmitting coil and the receiving coil, a predetermined power supply current is used to measure and obtain the corresponding induced electromotive force of the transmitting coil and the receiving coil at different vertical spacings, and then a function fitting is performed between the different spacings and the corresponding induced electromotive force to obtain a corresponding fitting function.

[0010] Furthermore, the receiving coil is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil is electrically connected to the signal transmitting device using an ordinary cable. The double-core shielded cable and the ordinary cable in the rock and soil layer are passed through a hard pipe and are respectively electrically connected to the signal receiving device and signal transmitting device corresponding to the stable area outside the rock and soil layer. The signal receiving device is electrically connected to the server through a wired or wireless network.

[0011] The deep buried rock and soil layer settlement monitoring method of the present invention is implemented as follows: including parameter determination, function fitting, coil burial, and settlement monitoring steps. The specific contents of each step are as follows: A. Parameter determination: According to the implementation conditions of the monitoring site, determine the size of the transmitting coil and receiving coil, the cross-sectional area and number of turns of the enameled wire, and the size of the power supply current; B. Function Fitting: A transmitting coil and a receiving coil are manufactured according to the parameters determined above. Then, the induced electromotive force corresponding to different vertical spacings between the transmitting coil and the receiving coil is measured using the supply current determined above. Then, a function fitting is performed between the different spacings and the corresponding induced electromotive force to obtain the corresponding fitting function. C. Coil burial: The transmitting coil and receiving coil prepared above are buried at the bottom and top of the monitored rock and soil layer respectively, and the transmitting coil and the receiving coil form a coaxial ring, and the vertical distance between the transmitting coil and the receiving coil is the same as the thickness of the monitored rock and soil layer. d same; D. Settlement monitoring: During the monitoring process, the transmitting coil is supplied with the power supply current determined in step A, and the induced electromotive force of the receiving coil is measured. The measured induced electromotive force is then substituted into the aforementioned fitting function to calculate the vertical distance between the transmitting coil and the receiving coil, thereby obtaining the thickness of the monitored rock and soil layer. d .

[0012] Furthermore, in the parameter determination step, the diameters of the transmitting coil and the receiving coil are equal and are circular rings of 0.8 to 1.5 m, and the ratio of the number of turns of the enameled wire of the transmitting coil to that of the receiving coil is 100:800 to 1500; the power supply current of the transmitting coil is based on the ability to effectively identify the signal in the receiving coil at the maximum spacing.

[0013] Furthermore, in the function fitting step, the measured value of the transmitting coil and the receiving coil is 0.1 d ~1.2 dThe induced electromotive force corresponding to several different spacings within the range is then used as the independent variable to perform logarithmic function fitting or polynomial function fitting to obtain the corresponding fitting function.

[0014] Furthermore, the function fitting adopts a numerical analysis method or Excel, Matlab to obtain the fitted function and the error function.

[0015] Furthermore, in the coil burying step, the transmitting coil and the receiving coil are pre-buried during the construction period or laid out in a pit later, the receiving coil is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil is electrically connected to the signal transmitting device using an ordinary cable.

[0016] Furthermore, in the settlement monitoring step, the thickness of the rock and soil layer obtained d Compare with historical data to obtain the thickness of the monitored rock and soil layer d The change of the rock and soil layer thickness d The variation of the value and the monitoring time are used as independent variables to perform function fitting and form a fitting curve to obtain the thickness of the monitored rock and soil layer. d 's changing trend.

[0017] The present invention has the following beneficial effects: 1. The present invention utilizes the characteristic that magnetic field strength is related to the transmission and reception distance. By pre-measurement, the induced electromotive force corresponding to different vertical spacings between the transmitting and receiving coils is obtained. Function fitting is then performed on the different spacings and the corresponding induced electromotive force, thereby establishing an accurate relationship model between the induced electromotive force and the vertical spacing. The transmitting and receiving coils are then buried in the monitored rock and soil layer. Finally, the actual monitored induced electromotive force is substituted into the relationship model to monitor the settlement of the rock and soil layer. Therefore, the present invention not only realizes automatic monitoring, but also simplifies settlement monitoring operation, reduces or even eliminates the influence of tools and human factors, and can achieve higher monitoring accuracy. In particular, comparing the monitoring data with historical data and performing trend analysis can further improve the accuracy and reliability of monitoring.

[0018] 2. The settlement monitoring device of the present invention is mainly composed of a transmitting coil, a receiving coil, a signal transmitting device, a signal receiving device and a server. Compared with traditional monitoring equipment, the structure is clear and concise, which reduces the complexity of the equipment and the difficulty of maintenance.

[0019] 3. Since the settlement monitoring device of the present invention only buries the transmitting coil and the receiving coil in the rock and soil layer, and the signal transmitting and receiving electronic equipment can be set up in a safe and reliable environment, and the server can be remotely arranged, compared with traditional monitoring equipment, not only do complex electronic components do not need to be buried in the rock and soil layer, but the risk of equipment damage and monitoring failure due to environmental factors can be reduced or even avoided, thereby improving the reliability of the measuring device; in particular, the cable is passed through the hard pipe, which can further ensure the stability and reliability of signal transmission.

[0020] 4. The settlement monitoring device of the present invention can avoid the high maintenance costs caused by the easy damage of electronic equipment buried in deep rock and soil layers in traditional monitoring methods. In addition, the structure and manufacturing process of core components such as transmitting and receiving coils are relatively simple, which reduces the equipment procurement, installation and subsequent maintenance costs, and overall reduces the monitoring cost.

[0021] 5. The settlement monitoring method of the present invention has clear and specific steps, each step is highly operational, and does not require complicated operating procedures and professional skills, making it easy for engineering personnel to master and implement it; and the later monitoring process is easy to realize automatic monitoring, which can reduce or even eliminate the influence of tools and human factors, and improve the monitoring accuracy and real-time monitoring.

[0022] In summary, the present invention has the characteristics of simple structure, low cost, safety and reliability, easy operation and high monitoring accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of magnetic coil monitoring; Figure 2 The transmit-receive distance under given conditions d The relationship curve with Hz at the receiving coil; Figure 3 The transmit-receive distance under given conditions d Relationship curve with the induced electromotive force V of the receiving coil; Figure 4 This is a schematic diagram of the application structure of the deep-buried rock and soil layer settlement monitoring device of the present invention; In the figure, 1-transmitting coil, 2-receiving coil, 3-magnetic flux lines, 4-rock and soil layer, 5-hard pipe, 6-monitoring room, 7-top boundary of rock and soil layer landfill. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the scope of protection of the present invention.

[0025] like Figure 4As shown, the deep buried rock and soil layer settlement monitoring device of the present invention includes a transmitting coil 1, a receiving coil 2, a signal transmitting device, a signal receiving device, and a server. The transmitting coil 1 and the receiving coil 2 are respectively buried at the bottom and the top of the monitored rock and soil layer 4 to form a coaxial ring. The vertical distance between the transmitting coil 1 and the receiving coil 2 is the same as the thickness d of the monitored rock and soil layer 4. The receiving coil 2 is electrically connected to a signal receiving device, the transmitting coil 1 is electrically connected to a signal transmitting device, and the signal receiving device is electrically connected to a server.

[0026] The transmitting coil 1 and the receiving coil 2 have the same diameter and are circular rings of 0.8 to 1.5 m. The ratio of the number of turns of the enameled wire of the transmitting coil 1 to that of the receiving coil 2 is 100:800 to 1500. The power supply current of the transmitting coil 1 is based on the effective recognition of the signal in the receiving coil 2 at the maximum spacing.

[0027] Before burying the transmitting coil 1 and the receiving coil 2, a predetermined power supply current is used to measure and obtain the corresponding induced electromotive force of the transmitting coil 1 and the receiving coil 2 at different vertical spacings. Then, a function fitting is performed between the different spacings and the corresponding induced electromotive force to obtain a corresponding fitting function.

[0028] The receiving coil 2 is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil 1 is electrically connected to the signal transmitting device using an ordinary cable. The double-core shielded cable and the ordinary cable in the rock and soil layer 4 are passed through the hard pipe 5 and are respectively electrically connected to the signal receiving device and the signal transmitting device corresponding to the stable area outside the rock and soil layer 4. The signal receiving device is electrically connected to the server via a wired or wireless network.

[0029] like Figure 4 As shown, the deep buried rock and soil layer settlement monitoring method of the present invention is characterized by comprising the steps of parameter determination, function fitting, coil embedding, and settlement monitoring. The specific contents of each step are as follows: A. Parameter determination: Based on the implementation conditions of the monitoring site, determine the size of the transmitting coil 1 and the receiving coil 2, the cross-sectional area and number of turns of the enameled wire, and the size of the power supply current; B. Function Fitting: A transmitting coil 1 and a receiving coil 2 are manufactured according to the parameters determined above. Then, using the supply current determined above, the induced electromotive force corresponding to different vertical spacings between the transmitting coil 1 and the receiving coil 2 is measured. Function fitting is then performed to determine the corresponding fitting function by fitting the different spacings to the corresponding induced electromotive force. C. Coil burial: The transmitting coil 1 and receiving coil 2 prepared above are buried at the bottom and top of the monitored rock and soil layer 4 respectively, and the transmitting coil 1 and the receiving coil 2 form a coaxial ring, and the vertical distance between the transmitting coil 1 and the receiving coil 2 is the same as the thickness of the monitored rock and soil layer 4. d same; D. Subsidence monitoring: During the monitoring process, the transmitting coil 1 is supplied with the power supply current determined in step A, and the induced electromotive force of the receiving coil 2 is measured. The measured induced electromotive force is then substituted into the aforementioned fitting function to calculate the vertical distance between the transmitting coil 1 and the receiving coil 2, thereby obtaining the thickness of the monitored rock and soil layer 4. d .

[0030] In the parameter determination step, the transmitting coil 1 and the receiving coil 2 have the same diameter and are circular rings of 0.8 to 1.5 m. The ratio of the number of turns of the enameled wire of the transmitting coil 1 to that of the receiving coil 2 is 100:800 to 1500. The power supply current of the transmitting coil 1 is determined based on the effective recognition of the signal in the receiving coil 2 at the maximum spacing.

[0031] In the function fitting step, the actual measurement results show that the transmitting coil 1 and the receiving coil 2 are 0.1 d ~1.2 d The induced electromotive force corresponding to several different spacings within the range is then used as the independent variable to perform logarithmic function fitting or polynomial function fitting to obtain the corresponding fitting function.

[0032] The function fitting adopts a numerical analysis method or Excel, Matlab to obtain the fitting function and the error function.

[0033] In the coil burying step, the transmitting coil 1 and the receiving coil 2 are pre-buried during the construction period or laid out in a pit later. The receiving coil 2 is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil 1 is electrically connected to the signal transmitting device using an ordinary cable.

[0034] In the settlement monitoring step, the thickness of the rock and soil layer 4 is also obtained. d Compare with historical data to obtain the thickness of the monitored rock and soil layer 4 d The change of the rock and soil layer 4 thickness d The variation of the monitored rock and soil layer 4 is obtained by fitting the function with the monitoring time as the independent variable and forming a fitting curve. d 's changing trend.

[0035] Principle of settlement monitoring: like Figure 1 As shown in the figure, the horizontally placed transmitting coil 1 can be simplified as a vertical magnetic dipole as a magnetic dipole source.M for: , Where: ,in I 0 is the current intensity of the transmitting coil 1, S is the area of ​​the transmitting coil 1, n is the number of turns of the transmitting coil 1; ω is the angular frequency of the transmitted signal; t For time; i Is an imaginary unit.

[0036] Since both the transmitting coil 1 and the receiving coil 2 are buried underground, the electromagnetic field generated by the vertical magnetic dipole source in the uniform full space is simplified according to the isotropic uniform full space model:

[0037] Where: is the observation point (located at the interface between the medium and the air, the interface is perpendicular to z direction of the electric field x Directional component; is the electric field at the observation point y Directional component; is the electric field at the observation point z Directional component; is the magnetic field of the observation point x Directional component; is the magnetic field of the observation point y Directional component; for z Direction of magnetic vector potential; r s =( x s ,y s ,z s ) is the source location, r =( x,y,z ) represents the location of the observation point; is the distance between the source and the observation point; , called the impedance ratio; , called admittance; μ is the magnetic permeability of the medium; σ is the dielectric conductivity; ε is the dielectric constant of the medium; k is the electromagnetic wave vector, .

[0038] The target of receiving coil 2 is ,It can be seen from the positional relationship between the designed transmitting coil 1 and receiving coil 2; x - xs = y - y s =0; R = z - z s = d This is the monitoring target, which includes: Using the common electromagnetic parameters of clay for simulation calculation, μ ≈ μ 0=4π×10 -7 H / m; σ =2×10 -4 S / m; ε ≈4 ε 0=3.542×10 -11 F / m. In addition, I 0=1A; ω =200πrad / s; S =0.25πm 2 ; n = 30. Calculation under this condition d The corresponding range is from 0.1 to 3m. The results are as follows Figure 2 shown.

[0039] Induced electromotive force of receiving coil 2 V and The relationship between them is expressed in the frequency domain as: Where: μ r is the relative magnetic permeability, μ r = μ / μ 0; S S is the area of ​​receiving coil 2, n s is the number of turns of receiving coil 2.

[0040] Then the induced electromotive force of the receiving coil 2 corresponding to d is 0.1 to 3m V like Figure 3 shown.

[0041] from Figure 3 It can be seen that when d When the size changes, V The size of d The two are one-to-one corresponding in the possible value range of . Measure the induced electromotive force of the receiving coil 2 VThe size of can be used to obtain the corresponding sending and receiving distance d The size of the soil layer 4 is used to monitor the settlement changes. Example

[0042] like Figure 4 As shown, the settlement monitoring of deep buried rock and soil layer is as follows: S100: Both the transmitting coil 1 and the receiving coil 2 are circular rings with a diameter of 1 meter. The transmitting coil 1 uses a cross-sectional area of ​​1.2mm 2 The receiving coil 2 uses an enameled wire with a cross-sectional area of ​​0.35mm 2 The supply current is related to the transmission and reception distance, which is determined based on the thickness of the rock formation being monitored. The supply current for transmitting coil 1 is determined based on the maximum distance between them, ensuring that the signal from receiving coil 2 can be effectively recognized. If the power supply capacity is insufficient, the diameters of transmitting coil 1 and receiving coil 2 can be increased, as can the number of turns in receiving coil 2, to improve signal strength.

[0043] S200: Get the thickness of the rock and soil layer 4 to be monitored d As the actual buried receiving and transmitting distance, measure 0.1 d ~1.2 d The induced electromotive force of the receiving coil 2 under the conditions of receiving and transmitting distance V And the receiving and sending distance and induced electromotive force V For the independent variable, a logarithmic function or a polynomial function is fitted. Function fitting can be performed using numerical analysis methods or using tools such as Excel and Matlab to obtain the fitted function and error function.

[0044] S300: Place the transmitting coil 1 at the bottom of the rock and soil layer 4 to be monitored, and bury the receiving coil 2 at the top, so that the transmitting coil 1 and the receiving coil 2 form a coaxial ring. The distance between the transmitting and receiving coils is the thickness of the rock and soil layer 4 to be monitored. d The transmitting coil 1 and the receiving coil 2 are pre-buried during the construction period, or laid out in the later stage. And the receiving coil 2 adopts a cross-sectional area of ​​4mm 2 The double-core shielded cable is electrically connected to the signal receiving device, and the cross-sectional area of ​​the transmitting coil 1 is 4mm 2 The conventional cables are electrically connected to the signal transmitter. The dual-core shielded cables and conventional cables are transported via rigid conduit 5 to a stable area outside the landfill site. There, they are connected to the signal receiver and transmitter, respectively, located in a monitoring room 6 or monitoring box. Both devices are powered by mains electricity or solar energy.

[0045] S400: During the monitoring process, the transmitting coil 1 is supplied with the power supply current determined in S100, and the induced electromotive force of the receiving coil 2 is measured. Vsize; then, according to the site conditions, the measured induced electromotive force V The measured induced electromotive force is transmitted to the server via a wired or wireless network. V Substitute the above fitting function to calculate the vertical distance between the transmitting coil 1 and the receiving coil 2, and then obtain the thickness of the monitored rock and soil layer 4 d , and provide monitoring data to users through web pages when necessary.

[0046] The server will also get the thickness of the geotechnical layer 4 d Compare with historical data to obtain the thickness of the monitored rock and soil layer 4 d The change of Δ d ; Then the soil layer 4 thickness d The change of Δ d The monitoring time is used as the independent variable to perform function fitting and form a fitting curve to obtain the thickness of the monitored rock and soil layer 4. d The changing trends are peeled off and provided to users.

[0047] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A deep buried rock and soil layer settlement monitoring device, characterized by: It includes a transmitting coil (1), a receiving coil (2), a signal transmitting device, a signal receiving device, and a server. The transmitting coil (1) and the receiving coil (2) are respectively buried at the bottom and the top of the monitored deep-buried rock and soil layer (4) to form a coaxial ring, and the vertical spacing between the transmitting coil (1) and the receiving coil (2) is the same as the thickness d of the monitored rock and soil layer (4); The receiving coil (2) is electrically connected to a signal receiving device, the transmitting coil (1) is electrically connected to a signal transmitting device, and the signal receiving device is electrically connected to a server.

2. The deep-buried rock and soil layer settlement monitoring device according to claim 1, characterized in that: The transmitting coil (1) and the receiving coil (2) have the same diameter and are circular rings of 0.8 to 1.5 m. The ratio of the number of winding turns of the enameled wire of the transmitting coil (1) to that of the receiving coil (2) is 100:800 to 1500. The power supply current of the transmitting coil (1) is based on the signal in the receiving coil (2) that can be effectively recognized when the maximum spacing is achieved.

3. The deep-buried rock and soil layer settlement monitoring device according to claim 1, characterized in that: Before the transmitting coil (1) and the receiving coil (2) are buried, a predetermined power supply current is used to measure and obtain the corresponding induced electromotive force of the transmitting coil (1) and the receiving coil (2) at different vertical spacings, and then a function fitting is performed between the different spacings and the corresponding induced electromotive force to obtain a corresponding fitting function.

4. The deep buried rock and soil layer settlement monitoring device according to claim 1, 2 or 3, characterized in that: The receiving coil (2) is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil (1) is electrically connected to the signal transmitting device using an ordinary cable. The double-core shielded cable and the ordinary cable in the rock and soil layer (4) are passed through a hard pipe (5) and are respectively electrically connected to the signal receiving device and the signal transmitting device corresponding to the stable area outside the rock and soil layer (4). The signal receiving device is electrically connected to the server via a wired or wireless network.

5. A method for monitoring settlement of a deep-buried rock and soil layer, characterized by: It includes parameter determination, function fitting, coil burial, and settlement monitoring steps. The specific contents of each step are as follows: A. Parameter determination: Based on the implementation conditions of the monitoring site, determine the size of the transmitting coil (1) and the receiving coil (2), the cross-sectional area and number of turns of the enameled wire, and the size of the power supply current; B. Function fitting: A transmitting coil (1) and a receiving coil (2) are respectively manufactured according to the parameters determined above, and then the induced electromotive force corresponding to different vertical spacings between the transmitting coil (1) and the receiving coil (2) is measured using the power supply current determined above, and then a function fitting is performed between the different spacings and the corresponding induced electromotive force to obtain a corresponding fitting function; C. Coil burial: The transmitting coil (1) and receiving coil (2) prepared above are buried at the bottom and top of the monitored rock and soil layer (4) respectively, and the transmitting coil (1) and the receiving coil (2) form a coaxial ring, and the vertical distance between the transmitting coil (1) and the receiving coil (2) is equal to the thickness of the monitored rock and soil layer (4). d same; D. Subsidence monitoring: During the monitoring process, the transmitting coil (1) is supplied with the power supply current determined in step A, and the induced electromotive force of the receiving coil (2) is measured. The measured induced electromotive force is then substituted into the aforementioned fitting function to calculate the vertical distance between the transmitting coil (1) and the receiving coil (2), thereby obtaining the thickness of the monitored rock and soil layer (4). d .

6. The method for monitoring settlement of a deep buried rock and soil layer according to claim 5, characterized in that: In the parameter determination step, the transmitting coil (1) and the receiving coil (2) have the same diameter and are circular rings of 0.8 to 1.5 m, and the ratio of the number of winding turns of the enameled wire of the transmitting coil (1) to that of the receiving coil (2) is 100:800 to 1500; the power supply current of the transmitting coil (1) is based on the signal in the receiving coil (2) that can be effectively recognized when the maximum spacing is achieved.

7. The method for monitoring settlement of a deep buried rock and soil layer according to claim 5, characterized in that: In the function fitting step, the measured value of the transmitting coil (1) and the receiving coil (2) is 0.1 d ~1.2 d The induced electromotive force corresponding to several different spacings within the range is then used as the independent variable to perform logarithmic function fitting or polynomial function fitting to obtain the corresponding fitting function.

8. The method for monitoring settlement of a deep buried rock and soil layer according to claim 7, characterized in that: The function fitting adopts a numerical analysis method or Excel, Matlab to obtain the fitting function and the error function.

9. The method for monitoring settlement of a deep buried rock and soil layer according to claim 5, characterized in that: In the coil burying step, the transmitting coil (1) and the receiving coil (2) are pre-buried during the construction period or laid out in a pit at a later stage, the receiving coil (2) is electrically connected to the signal receiving device using a double-core shielded cable, and the transmitting coil (1) is electrically connected to the signal transmitting device using an ordinary cable.

10. The method for monitoring settlement of deep buried rock and soil layers according to any one of claims 5 to 9, characterized in that: In the settlement monitoring step, the thickness of the rock and soil layer (4) will also be obtained. d Compare with historical data to obtain the thickness of the monitored rock and soil layer (4) d The change of the rock and soil layer (4) d The variation of the value and the monitoring time are used as independent variables to perform function fitting and form a fitting curve to obtain the thickness of the monitored rock and soil layer (4) d 's changing trend.

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