A coal mine tunnel shield tunneling multi-frequency alternating current parallel advanced detection method and system

Abstract

The application discloses a kind of coal mine tunnel shield with the method and system of frequency parallel advanced detection of excavating, method includes: in the direction of roadway excavation, three-direction data observation system is arranged;To the three-direction data observation system of arrangement, take multi-frequency pseudo-random electric couple source emission mode, collect three-direction potential difference amplitude and three-direction potential difference phase value;The three-direction potential difference amplitude and potential difference phase value obtained are sent into the professional software based on Cole-Cole model inversion, obtain three-dimensional apparent resistivity image and three-dimensional apparent chargeability image;Based on three-dimensional apparent resistivity image and three-dimensional apparent chargeability image joint determination water-rich anomaly, the present application solves the problems such as insufficient spatial positioning of traditional advanced detection method to geological body and roadway shield under the condition of excavating and exploring, and provides technical support for roadway shield with the detection of water damage of excavating.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mine tunnel shield tunneling, in particular to a coal mine tunnel shield tunneling multi-frequency alternating current parallel advanced detection method and system. BACKGROUND

[0002] In the process of coal mine deep roadway tunneling, encountering concealed faults, collapse columns, karst caves, fracture zones and other unfavorable geological bodies is a common challenge. Once these geological bodies are water-rich, serious water inrush accidents such as water inrush may occur, which poses a serious threat to the safety of miners and production efficiency. Therefore, implementing advanced geological detection has become a key link in the prevention and control of water disasters in coal mines. Currently, geological radar method, transient electromagnetic method, direct current resistivity method and double-frequency induced polarization method are widely used in the detection of water-bearing properties of geological bodies in front of the tunnel. However, these methods have their own limitations: the geological radar method is affected by the fast energy attenuation of high-frequency electromagnetic waves and the unevenness of the medium, has a short detection distance, and is easily disturbed by metal, resulting in low signal-to-noise ratio; the transient electromagnetic method has a shallow detection blind area and is seriously disturbed by metal in the tunnel, affecting the actual detection effect; the direct current resistivity method and the double-frequency induced polarization method have high sensitivity to the water-bearing properties of geological bodies and long detection distance, but they can only observe the electrical parameters along the strike of the tunnel, and cannot accurately realize the spatial positioning of the geological body, resulting in insufficient advanced detection accuracy.

[0003] In view of these technical problems, the invention patent with the patent publication number CN103645514A proposes a multi-same source electrode array resistivity underground engineering advanced detection method and system. This method mainly uses the three-pole detection mode of the direct current resistivity method, measures the power supply current and potential difference by arranging power supply electrodes at the working face and behind the tunnel, and moving the measurement electrodes in the axial direction of the tunnel, and calculates the apparent resistivity value. However, this method has limited ability to capture parameters such as occurrence, size and resistivity of concealed geological anomalies, and is not sensitive to abnormal bodies far from the tunneling working face, resulting in poor detection accuracy.

[0004] To further improve the detection accuracy, the invention patents with the patent publication numbers CN111650652A, CN112505786A and CN111856594A respectively propose a three-direction apparent resistivity, apparent polarization rate and video scattering rate advanced detection method for tunnels. These methods arrange power supply points and measurement points on the measurement line, observe the three-direction potential difference, calculate the three-direction electrical parameters, and obtain the three-dimensional electrical parameter image of the geological body in front of the tunnel through inversion, to determine the spatial position of the concealed disaster geological body and its water-bearing property.

[0005] However, the above three-directional apparent resistivity, apparent polarization rate and apparent dispersion rate and other electrical parameters face some limitations in data observation and inversion process: (1) the negative electrode B of the power supply is placed behind the roadway excavation, which makes the current line propagate along the rear of the roadway, and the capture ability of the far distance water-rich abnormal body in front of the roadway is weak, resulting in short roadway advanced detection distance of the above method; (2) when observing the frequency dispersion rate and polarization rate, only the amplitude information of the electric field is observed, and the phase information is not observed, resulting in poor accuracy of the subsequent obtained apparent polarization rate and apparent dispersion rate and other parameters, and the influence of the interference information around the roadway; (3) the comprehensive interpretation method between apparent resistivity, apparent polarization rate and apparent dispersion rate is not clarified, and intelligent identification of water-rich abnormality in roadway excavation cannot be achieved.

[0006] In addition, the invention patents with patent publication numbers CN105891890A and CN113156518A give a detection method under the condition of shield tunneling, but do not specifically explain the data observation information and interpretation method, or only observe the apparent resistivity, still facing the problem of resistivity multi-solution.

[0007] There are significant differences between coal mine roadway shield tunneling and traditional ground tunneling. The large space occupied by the shield machine device makes it difficult to implement the traditional construction method; at the same time, the medium of coal mine roadway is coal rock mass, and the water content is low, and the conductivity is poor, so the three-dimensional induced polarization and focused current devices used in ground tunnels are difficult to be well coupled with the medium in coal mine roadway, and cannot be applied. Therefore, with the acceleration of intelligent construction of coal mines in China and the popularization of coal mine roadway shield tunneling construction, it is urgent to develop a new method suitable for coal mine roadway shield tunneling and water hazard advanced detection. SUMMARY

[0008] The technical problem to be solved by the present application is to provide a coal mine roadway shield tunneling and multi-frequency alternating current parallel advanced detection method.

[0009] To solve the above technical problems, the present application provides the following technical scheme:

[0010] A coal mine roadway shield tunneling and multi-frequency alternating current parallel advanced detection method, comprising:

[0011] In the direction of roadway excavation, a three-directional data observation system is arranged;

[0012] A multi-frequency pseudo-random electric double source emission mode is adopted for the arranged three-directional data observation system, and three-directional potential difference amplitude values and three-directional potential difference phase values are collected;

[0013] The obtained three-directional potential difference amplitude values and potential difference phase values are sent into a professional software based on Cole-Cole model for inversion, and three-dimensional apparent resistivity images and three-dimensional apparent charging rate images are obtained;

[0014] The water-rich anomaly is determined based on the three-dimensional apparent resistivity image and the three-dimensional apparent chargeability image.

[0015] In an embodiment of the present application, a three-direction data observation system is arranged, comprising:

[0016] S11, the tunneling direction is set as the positive direction of x-axis, the vertical upward direction is set as the positive direction of y-axis, and the tunnel side is set as the positive direction of z-axis, a spatial rectangular coordinate system is established, and an electrical method survey line is arranged along the negative direction of x-axis on the tunnel side, and the starting point of the electrical method survey line is the intersection of the tunneling working face and the electrical method survey line;

[0017] S12, s control points are arranged at a distance d from the starting point of the electrical method survey line to the rear of the tunnel, and three electrode holes are constructed at each control point by using the anchor rod drill carried by the shield machine; after the construction of all electrode holes is completed, the electrode holes are filled with conductive medium by using an injection device, and a set of power supply-measuring electrode group is installed at the three electrode holes of each control point;

[0018] S13, the three electrode holes of each control point are numbered as V1, V2 and V3 respectively, and the hole depth direction of each electrode hole is perpendicular to the tunnel side and constructed along the positive direction of z-axis; wherein, the electrode hole V1 is located at the control point position; the electrode hole V2 is located above the electrode hole V1 along the positive direction of y-axis; and the electrode hole V3 is located behind the electrode hole V1 along the negative direction of x-axis;

[0019] S14, the power supply-measuring electrode is installed in the electrode hole V1 of each control point, and the measuring electrodes are installed in the electrode hole V2 and the electrode hole V3 respectively; all control points are connected through the electrical method survey line and connected with the multi-frequency parallel electrical method instrument to form a complete power supply-measuring loop.

[0020] In an embodiment of the present application, the height of the electrical method survey line from the tunnel bottom surface is consistent with the height of the anchor rod drill carried on the shield machine.

[0021] In an embodiment of the present application, the first four control points A1-A4 of the arranged three-direction data observation system are used as power supply points to emit multi-frequency alternating current fields to the surrounding rock in turn, and each control point receives three-direction data when the others emit; then, the three-direction potential difference amplitude values and the three-direction potential difference phase values are collected, including:

[0022] S21, the power supply-measuring electrode group installed in the control point position includes one power supply-measuring electrode and two measuring electrodes, the No. 1 electrode sheet of the power supply-measuring electrode is numbered as P1, the No. 2 electrode sheet is numbered as P2, and the electrode sheets of the two measuring electrodes are numbered as P3 and P4 respectively; first, the No. 1 electrode sheet and the No. 2 electrode sheet in the power supply-measuring electrode in the control point A1 are used as the power supply positive electrode A and the power supply negative electrode B respectively to form an electric couple source emission mode, and the two measuring electrodes are used as the measuring electrodes C and D respectively to form a three-electrode measurement mode, and the two measuring electrodes are used as the measuring electrodes C and D respectively to form a three-electrode measurement mode. 1 、2 2 ……27 Multi-frequency pseudo-random signal synthesis emission, and record power supply current I i The rest of the control points in turn receive the potential difference amplitude ΔU corresponding to all frequency pairs between P1P2, P3P2, P4P2 x i ), ΔU y i ), ΔU z i ) and potential difference phase value ΔF x i ), ΔF y i ), ΔF z i , where f i represents different alternating current field frequencies; i represents the control point number; the above process completes the three-direction multi-frequency alternating current field data of the rest of the control points corresponding to the power supply of the control point A1;

[0023] S22, the control point A2 supplies multi-frequency pseudo-random alternating current field to the ground, and the potential difference amplitude ΔU x i ), ΔU y i ), ΔU z i ) and potential difference phase value ΔF x i ), ΔF y i ), ΔF z i ; in this way, the three-direction multi-frequency alternating current field data of the first four control points are collected in turn.

[0024] In an embodiment of the present application, based on Cole-Cole model inversion, three-dimensional apparent resistivity images and three-dimensional apparent chargeability images are obtained through the following formula:

[0025]

[0026] In the formula, ρ(iω) represents the resistivity at an angular frequency of ω, ρ0 represents the resistivity at a frequency of zero, m represents the chargeability, τ represents the time constant, c represents the frequency correlation coefficient, and i represents the imaginary unit; wherein the potential difference amplitude and the potential difference phase value are used to describe the resistivity and the chargeability; using the three-direction amplitude and phase data, three-dimensional apparent resistivity images and three-dimensional apparent chargeability images are obtained through professional software inversion.

[0027] ​​​​​​​​​​​​In an embodiment of the present application, the three-dimensional grid of the detection area is established when the apparent resistivity and apparent chargeability are inversed, the apparent resistivity and apparent chargeability in each grid are calculated, the smooth constrained least square inversion algorithm is adopted, and the apparent resistivity and apparent chargeability inversion objective function is:

[0028] S(m) = [d - g(m)] T W d [d - g(m)];

[0029] In the formula, g is the theoretical alternating current field data matrix, d is the measured alternating current field data matrix, m is the resistivity matrix or chargeability matrix of the model, W d is the weight coefficient matrix; in order to make S(m) converge, the resistivity or chargeability m is modified for multiple times during inversion, and the modification relationship is:

[0030] (J T W d J + λI)Δm = J T W d [d - g(m)];

[0031] In the formula, J is the Jacobi matrix, J T is the transpose matrix of J, λ is the damping factor, and I represents the unit matrix.

[0032] In an embodiment of the present application, during the forward construction of the shield machine, the anchor drill of the shield machine constructs a control point every certain distance; the power supply-measuring electrode group and the multi-frequency parallel electrical method instrument of all control points in the rear are moved forward together, the moving interval and the number of control points are related to the tunneling footage of the day, and in principle, the control point A1 is the nearest measuring point to the working face.

[0033] In an embodiment of the present application, the water-rich anomaly is jointly judged based on the three-dimensional apparent resistivity image and the three-dimensional apparent chargeability image, which comprises:

[0034] S41, according to the physical property parameter test result of the working area, the apparent resistivity and apparent chargeability threshold values of the water-rich anomaly are set, the three-dimensional boundary coordinates of each low-resistance anomaly area in the three-dimensional apparent resistivity image are extracted, and the anomaly areas are numbered as R1, R2, …, R j ; the three-dimensional boundary coordinates of the high-chargeability anomaly area in the three-dimensional apparent chargeability image are extracted, and the anomaly areas are numbered as M1, M2, …, M k ;

[0035] S42, the apparent resistivity anomaly area R1 is compared with the apparent chargeability anomaly areas M1, M2, …, M kPerform spatial correlation analysis and consider the area where the apparent resistivity anomaly area and the apparent charge rate anomaly area overlap in space as a high-probability water-rich anomaly; a single apparent resistivity anomaly or apparent charge rate anomaly is considered a low-probability water-rich anomaly; and so on for the apparent resistivity anomaly areas R2, ..., R j Respectively with the apparent charging rate abnormal area M1, M2, ..., M k Conduct spatial correlation analysis to obtain all abnormal water-rich areas in the work area and rank them by probability to provide a reference for the production department.

[0036] The present invention further provides a multi-frequency AC parallel advance detection system for a coal mine tunnel shield during tunneling, which uses the above-mentioned multi-frequency AC parallel advance detection method for a coal mine tunnel shield during tunneling, comprising:

[0037] The observation system module is used to deploy a three-directional data observation system in the tunnel excavation direction;

[0038] The potential and phase acquisition module is used to collect the three-directional potential difference amplitude and three-directional potential difference phase values ​​of the deployed three-directional data observation system using a multi-frequency pseudo-random electric dipole source emission mode;

[0039] The apparent resistivity and apparent charge rate module is used to input the acquired three-directional potential difference amplitude and potential difference phase values ​​into professional software based on the Cole-Cole model for inversion, thereby obtaining a three-dimensional apparent resistivity image and a three-dimensional apparent charge rate image.

[0040] The joint determination module is used to jointly determine the water-rich anomaly based on the three-dimensional apparent resistivity image and the three-dimensional apparent charge rate image.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) In view of the special conditions of tunnel shield construction space, a method for advanced water hazard detection during tunneling is proposed, which is suitable for coal mine tunnel shield excavation conditions and meets the current practical needs of tunnel shield excavation and detection.

[0043] (2) The multi-frequency AC parallel advance detection method for shield tunneling in coal mine tunnels adopts a multi-frequency pseudo-random parallel AC emission and acquisition mode, which has high data acquisition efficiency, more comprehensive physical field information, and richer and more reliable physical property characteristic information, providing support for real-time and high-precision prediction of geological water bodies ahead of tunnel excavation.

[0044] (3) Taking advantage of the low resistance and high charge rate characteristics of water-rich anomalies, an intelligent identification method for geological water bodies was proposed through the joint inversion of the three-dimensional apparent resistivity and three-dimensional apparent charge rate in front of the tunnel. This method overcomes the multi-solution problem faced by the traditional method of using only a single electrical parameter to explain water-rich anomalies, and greatly improves the accuracy of tunnel excavation detection.

[0045] (4) Solve the problems of traditional advanced detection methods, such as insufficient spatial positioning of geological bodies and tunneling while detecting, and provide technical support for tunneling while detecting water hazards for a roadway shield. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 A flow chart of a coal mine roadway shield tunneling multi-frequency alternating current parallel advanced detection method according to an embodiment of the present application.

[0047] Figure 2 A power-supplying-measuring electrode group schematic diagram according to an embodiment of the present application.

[0048] Figure 3 A three-direction data observation system layout three-dimensional schematic diagram according to an embodiment of the present application.

[0049] Figure 4 A two-dimensional profile schematic diagram extracted from three-dimensional apparent resistivity inversion data according to an embodiment of the present application.

[0050] Figure 5 A two-dimensional profile schematic diagram extracted from three-dimensional apparent chargeability inversion data according to an embodiment of the present application.

[0051] Figure 6 A coal mine roadway shield tunneling multi-frequency alternating current parallel advanced detection system block diagram according to an embodiment of the present application. DETAILED DESCRIPTION

[0052] To facilitate those skilled in the art to understand the technical solutions of the present application, the technical solutions of the present application will be further described in conjunction with the drawings of the specification.

[0053] The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0054] Please refer to Figure 1 As shown in the drawings, the present application provides a coal mine roadway shield tunneling multi-frequency alternating current parallel advanced detection method, comprising:

[0055] S10, in the direction of roadway excavation, a three-direction data observation system is laid out.

[0056] In an embodiment of the present application, the three-direction data observation system is laid out, comprising:

[0057] S11, assuming that the tunneling direction of the roadway is the positive direction of the x-axis, the vertical upward direction is the positive direction of the y-axis, and the side of the roadway is the positive direction of the z-axis, a spatial rectangular coordinate system is established, and an electrical method survey line is arranged along the negative direction of the x-axis on the side of the roadway, and the starting point of the electrical method survey line is the intersection of the tunneling working face of the roadway and the survey line, that is, the origin of the spatial rectangular coordinate system. The height of the electrical method survey line from the bottom of the roadway is consistent with the height of the anchor drill carried on the shield machine.

[0058] S12, from the starting point of the electrical method survey line to the rear of the roadway, that is, the negative direction of the x-axis, a plurality of control points are arranged at a distance d, generally d = 4 m, such as Figure 3 A1, A2,..., and s ≥ 20. At each control point, three electrode holes are constructed by using the anchor drill carried by the shield machine, and the depth of each electrode hole is h = 0.8 m. After the construction of all the electrode holes is completed, the electrode holes are filled with conductive medium, generally clay, by using an injection device, and a set of power supply-measuring electrode group is installed for the three electrode holes of each control point.

[0059] S13, the three electrode holes of each control point are numbered as V1, V2 and V3 respectively, and the depth of each electrode hole is h = 0.8 m, and the depth direction is perpendicular to the side of the roadway, that is, it is constructed along the positive direction of the z-axis. Among them, the V1 hole is located at the control point, V2 is located above V1, that is, the positive direction of the y-axis, 0.5 m away, and V3 is located behind V1, that is, the negative direction of the x-axis, 0.5 m away.

[0060] S14, a power supply-measuring electrode is installed in the electrode hole V1 of each control point, and a measuring electrode is installed in the electrode hole V2 and the electrode hole V3 respectively. Among them, the power supply-measuring electrode is 80 cm long and contains two electrode pieces, each of which is 5 cm long. The center of No. 1 electrode piece is 15 cm away from the electrode tail end, the center of No. 2 electrode piece is 10 cm away from the electrode tip, and the center distance of the two electrode pieces is 50 cm. The measuring electrode is 80 cm long and contains an electrode piece, which is 5 cm long. The center is 10 cm away from the electrode tip, as shown in Figure 2 All control points are connected through the electrical method large line and connected with the multi-frequency parallel electrical method instrument 5 to form a complete power supply-measuring loop, as shown in Figure 3 The number 1 in the figure indicates the front of the roadway, the number 2 indicates the tunneling working face of the roadway, the number 3 indicates the roadway, the number 4 indicates the electrical method large line, the number 6 indicates the control point, the number 7 indicates the rear of the roadway, and the number 8 indicates the front cutter section of the shield machine.

[0061] S20, for the three-direction data observation system arranged, a multi-frequency pseudo-random electric double source emission mode is adopted, and the three-direction potential difference amplitude value and the three-direction potential difference phase value are collected.

[0062] In an embodiment of the present application, after the three-direction data observation system is installed, the three-direction multi-frequency alternating current field data acquisition is implemented. During the data acquisition process, the first four control points A1-A4 are used as power supply points, and multi-frequency alternating current field is transmitted to the surrounding rock in turn. When each control point transmits, the remaining control points receive three-direction data. The specific data acquisition method is as follows:

[0063] S21, each set of power supply-measuring electrode group contains one power supply-measuring electrode and two measuring electrodes. The electrode sheet number of the power supply-measuring electrode No. 1 is P1, the electrode sheet number of the power supply-measuring electrode No. 2 is P2, and the electrode sheet numbers of the two measuring electrodes are P3 and P4. First, the electrode sheet No. 1 and the electrode sheet No. 2 in the power supply-measuring electrode of the control point A1 are used as the power supply anode A and the power supply cathode B respectively to form an electric couple source transmission mode. 2 1 , 2 2 ……2 7 Multi-frequency pseudo-random signal synthesis transmission, and record the power supply current I i , the remaining control points receive the potential difference amplitude ΔU x (f i ), ΔU y (f i ), ΔU z (f i ) and the potential difference phase value ΔF x (f i ), ΔF y (f i ), ΔF z (f i ) corresponding to all frequencies between P1P2, P3P2 and P4P2, where f i represents different alternating current field frequencies; i represents the control point number; and the above process completes the three-direction multi-frequency alternating current field data of the remaining control points corresponding to the power supply of the control point A1.

[0064] S22, the control point A2 supplies multi-frequency pseudo-random alternating current field to the ground, and the potential difference amplitude ΔU x (f i ), ΔU y (f i ), ΔU z (f i ) and the potential difference phase value ΔF x (f i ), ΔF y (f i ), ΔF z (f i ) corresponding to all frequencies are obtained according to the data acquisition mode in S21. In this way, the three-direction multi-frequency alternating current field data of the first four control points are collected in turn.

[0065] S30, send the acquired three-direction potential difference amplitude value and potential difference phase value into professional software based on Cole-Cole model for inversion to acquire three-dimensional apparent resistivity image and three-dimensional apparent chargeability image.

[0066] In an embodiment of the present application, based on Cole-Cole model inversion, three-dimensional apparent resistivity image and three-dimensional apparent chargeability image are acquired through the following formula:

[0067]

[0068] In the formula, ρ(iω) represents the resistivity at the angular frequency ω, ρ0 represents the resistivity at the frequency of zero, m represents the chargeability, τ represents the time constant, c represents the frequency correlation coefficient, and i represents the imaginary unit; wherein the potential difference amplitude and the potential difference phase value are used to describe the resistivity and the chargeability.

[0069] Three-dimensional apparent resistivity image and three-dimensional apparent chargeability image are acquired by professional software inversion using three-direction amplitude and phase data. Specifically, the professional software is, for example, a tunnel audio frequency electrical imaging software.

[0070] In the present embodiment, Cole-Cole model inversion is a conventional technical means in the art, and the difference lies in that, at present, when observing frequency dispersion rate and polarization rate, only the amplitude information of the electric field is observed, and the phase information is not observed, which leads to poor precision of the apparent polarization rate and the apparent frequency dispersion rate obtained by Cole-Cole model inversion, and the parameters are easily affected by the interference information around the tunnel. However, the present application adds the observation of the phase information when using Cole-Cole model inversion.

[0071] In the present embodiment, further, the three-dimensional grid of the detection area is used when inverting the apparent resistivity and the apparent chargeability, the apparent resistivity and the apparent chargeability in each grid are calculated, the smooth constraint least square inversion algorithm is used, and the apparent resistivity and the apparent chargeability inversion objective function is:

[0072] S(m)=[d-g(m)] T W d [d-g(m)];

[0073] In the formula, g is the theoretical alternating current field data matrix, d is the measured alternating current field data matrix, m is the resistivity and chargeability matrix of the model, W d is the weight coefficient matrix; in order to make S(m) converge, the resistivity or the chargeability m is modified for multiple times during inversion, and the modification relationship is:

[0074] (J T W d J+λI)Δm=J T W d [d-g(m)];

[0075] In the formula, J is a Jacobi matrix, J T is the transpose matrix of J, λ is a damping factor, and I represents a unit matrix.

[0076] In the embodiment, the method for optimizing the resistivity and the charging rate can be understood as the same method.

[0077] In an embodiment of the application, during the forward construction of the shield machine, the shield machine anchor drill constructs a control point every 4 m. The power-supplying and measuring electrode groups and the multi-frequency parallel electrical method instrument and other equipment are collectively moved forward, and the moving interval and the number of control points are related to the tunneling footage of the day. In principle, the control point A1 is the closest measuring point to the working face.

[0078] S40, jointly determining the water-rich anomaly based on the three-dimensional apparent resistivity image and the three-dimensional apparent chargeability image.

[0079] In an embodiment of the application, considering that the rock resistivity is related to various factors such as the mineral composition, structure, bedding, temperature and pressure of the rock, the single apparent resistivity interpretation of the water-rich anomaly has multiple solutions. Therefore, the application adopts the apparent resistivity and apparent chargeability inversion images to jointly determine the water-rich anomaly area, specifically as follows:

[0080] S41, according to the physical property parameter test results of the working area, setting the apparent resistivity and apparent chargeability threshold values of the water-rich anomaly, extracting the three-dimensional boundary coordinates of each low-resistance anomaly area in the three-dimensional apparent resistivity image, and numbering the anomaly areas as R1, R2, …, R j , extracting the three-dimensional boundary coordinates of the high-chargeability anomaly area from the three-dimensional apparent chargeability image, and numbering the anomaly areas as M1, M2, …, M k . Specifically, in the embodiment, the apparent resistivity threshold value is 75 Ω·m, and the apparent chargeability threshold value is 1.7%.

[0081] S42, performing spatial correlation degree analysis on the apparent resistivity anomaly area R1 and the apparent chargeability anomaly areas M1, M2, …, M k , and regarding the area where the spatial positions of the apparent resistivity anomaly area and the apparent chargeability anomaly area coincide as a high-probability water-rich anomaly. The single apparent resistivity anomaly or apparent chargeability anomaly is regarded as a low-probability water-rich anomaly, and so on. The apparent resistivity anomaly areas R2, …, R j are respectively subjected to spatial correlation degree analysis with the apparent chargeability anomaly areas M1, M2, …, M k , to obtain all the water-rich anomaly areas of the working area, and to sort the probability of the water-rich anomaly areas, thereby providing a reference for the production department.

[0082] In an embodiment of the present application, for the above-mentioned specific parameters, as an implementation example. In order to facilitate expression, the two-dimensional profile data is extracted from the three-dimensional apparent resistivity and apparent chargeability data obtained by inversion of the tunneling detection data on the day, and isocharted, and the results show that, 12-17 m in front of the tunneling on the day, 23-35 m, presents low resistivity anomaly, see Figure 4 , 26-32 m in front of the tunneling, presents high chargeability anomaly, see Figure 5 , using the joint determination method of apparent resistivity anomaly and apparent chargeability anomaly of the present application, it is considered that the area of 26-32 m in front of the tunneling on the day is a high-probability water-rich anomaly area. The actual exposure results of the tunnel in the later period show that the area of 25-35 m in front of the tunneling on the detection day is due to geological structure fold uplift, and the rock fissure is developed and contains water.

[0083] The implementation example effect shows that the scheme of the present application has good applicability and reliability for the advanced water disaster detection of the tunnel shield tunneling, and can provide technical support for the safe tunneling of the tunnel shield.

[0084] Referring to Figures 1 to 6 , the present application also provides a coal mine tunnel shield tunneling multi-frequency alternating current parallel advanced detection system, which applies the coal mine tunnel shield tunneling multi-frequency alternating current parallel advanced detection method described above, comprising:

[0085] An observation system module is used to arrange a three-direction data observation system in the tunneling direction.

[0086] A potential and phase acquisition module is used to collect three-direction potential difference amplitude values and three-direction potential difference phase values in a multi-frequency pseudo-random electric couple source transmission mode for the arranged three-direction data observation system.

[0087] An apparent resistivity and apparent chargeability module is used to send the obtained three-direction potential difference amplitude values and potential difference phase values into professional software based on the Cole-Cole model for inversion, to obtain three-dimensional apparent resistivity images and three-dimensional apparent chargeability images.

[0088] A joint determination module is used to jointly determine water-rich anomalies based on the three-dimensional apparent resistivity images and the three-dimensional apparent chargeability images.

[0089] For those skilled in the art, it is obvious that the present application is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application, and any reference signs in the claims should not be regarded as limiting the claims involved.

[0090] The above-described embodiments are merely representative of the present application, and the scope of protection of the present application is not limited to the above-described embodiments. Those skilled in the art can make several modifications and improvements without departing from the concept of the present application, and these all belong to the scope of protection of the present application.

Claims

1. A method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels, characterized in that: include: In the direction of tunnel excavation, a three-directional data observation system is deployed, including: S11, assuming that the tunnel excavation direction is the positive x-axis, the vertical upward direction is the positive y-axis, and the tunnel side is the positive z-axis, establish a spatial rectangular coordinate system, and arrange an electrical survey line on the tunnel side along the negative x-axis direction. The starting point of the electrical survey line is the intersection of the tunnel excavation working face and the electrical survey line. S12, from the starting point of the electrical survey line, s control points are arranged in sequence at a distance d toward the rear of the tunnel; three electrode holes are constructed at each control point using an anchor drill rig mounted on a shield machine; after all electrode holes are constructed, each electrode hole is filled with a conductive medium using an injection device, and a set of power supply and measurement electrodes are installed in the three electrode holes at each control point; S13, the three electrode holes at each control point are numbered V1, V2, and V3, and the depth direction of each electrode hole is perpendicular to the side of the roadway and constructed along the positive z-axis. Among them, electrode hole V1 is located at the control point; electrode hole V2 is located above electrode hole V1, in the positive y-axis direction; electrode hole V3 is located behind electrode hole V1, in the negative x-axis direction; S14: Install a power supply and measurement electrode in electrode hole V1 of each control point, and install a measurement electrode in electrode hole V2 and electrode hole V3 respectively; connect all control points through the electrical method line and connect them to the multi-frequency parallel electrical method instrument to form a complete power supply and measurement circuit; For the deployed three-directional data observation system, a multi-frequency pseudo-random electric dipole source emission mode is adopted to collect the three-directional potential difference amplitude and three-directional potential difference phase values. Among them, the first four control points A1 to A4 of the deployed three-directional data observation system serve as power supply points, and transmit multi-frequency AC electric fields to the surrounding rock in sequence. When each control point transmits, the other control points receive three-directional data. The obtained three-directional potential difference amplitude and potential difference phase values ​​are sent to professional software based on the Cole-Cole model for inversion to obtain a three-dimensional apparent resistivity image and a three-dimensional apparent charge rate image; The water-rich anomaly is determined based on the combined use of 3D apparent resistivity images and 3D apparent charge rate images, including: S41, according to the test results of the physical parameters of the working area, set the apparent resistivity and apparent charge rate thresholds of the water-rich anomaly, extract the three-dimensional boundary coordinates of each low-resistance anomaly area in the three-dimensional apparent resistivity image, and number the anomaly areas as R1, R2, ..., R j ; Extract the 3D boundary coordinates of the high charging rate abnormal area from the 3D visual charging rate image, and number the abnormal area as M1, M2, ..., M k ; S42, the apparent resistivity abnormal area R1 and the apparent charge rate abnormal areas M1, M2, ..., M k Perform spatial correlation analysis and consider the area where the apparent resistivity anomaly area and the apparent charge rate anomaly area overlap in space as a high-probability water-rich anomaly; a single apparent resistivity anomaly or apparent charge rate anomaly is considered a low-probability water-rich anomaly; and so on for the apparent resistivity anomaly areas R2, ..., R j Respectively with the apparent charging rate abnormal area M1, M2, ..., M k Conduct spatial correlation analysis to obtain all abnormal water-rich areas in the work area and rank them by probability to provide a reference for the production department.

2. The method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels according to claim 1, characterized in that: The height of the electrical survey line from the bottom of the tunnel is consistent with the height of the anchor drilling rig carried on the shield machine.

3. The method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels according to claim 1, characterized in that: Collect the three-directional potential difference amplitude value and three-directional potential difference phase value, including: S21, the power supply-measurement electrode group installed in the control point includes a power supply-measurement electrode and two measurement electrodes. The electrode piece No. 1 of the power supply-measurement electrode is numbered as P1, the electrode piece No. 2 is numbered as P2, and the electrode pieces of the two measurement electrodes are numbered as P3 and P4 respectively; first, the electrode piece No. 1 and the electrode piece No. 2 of the power supply-measurement electrode in the control point A1 are used as the power supply positive electrode A and the power supply negative electrode B respectively, forming a galvanic source emission mode, and each emission adopts 2 1 , 2 2 ……2 7 Multi-frequency pseudo-random signal synthesis is transmitted, and the power supply current I is recorded i The remaining control points receive the potential difference amplitude ΔU corresponding to all frequencies between P1P2, P3P2, and P4P2 in turn. x (f i ),ΔU y (f i ),ΔU z (f i ) and the potential difference phase value Δ (f i ),Δ (f i ),Δ (f i ), where f i Indicates different AC electric field frequencies; i represents the control point number; the above process completes the three-directional multi-frequency AC electric field data of the remaining control points corresponding to the control point A1 power supply station; S22, control point A2 supplies a multi-frequency pseudo-random AC electric field to the ground, and obtains the potential difference amplitude ΔU corresponding to all frequencies according to the data acquisition method in S21. x (f i ),ΔU y (f i ),ΔU z (f i ) and the potential difference phase value Δ (f i ),Δ (f i ),Δ (f i ); and so on, collect the three-directional multi-frequency AC electric field data of the first four control points in turn.

4. The method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels according to claim 1, characterized in that: Based on the Cole-Cole model inversion, the three-dimensional apparent resistivity image and the three-dimensional apparent charge rate image are obtained by the following formula: ； Where, The angular frequency is expressed as The resistivity at Expressed as the resistivity when the frequency is zero, Expressed as the charging rate, Expressed as a time constant, Expressed as the frequency correlation coefficient, It is expressed as an imaginary unit; the potential difference amplitude and potential difference phase values ​​are used to describe the resistivity and charge rate; the three-dimensional apparent resistivity image and the three-dimensional apparent charge rate image are obtained by inversion using professional software using the three-directional amplitude and phase data.

5. The method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels according to claim 1, characterized in that: When inverting the apparent resistivity or apparent charge rate, the detection area is gridded in three dimensions, and the apparent resistivity and apparent charge rate in each grid are calculated. The smoothness-constrained least squares inversion algorithm is used, and the apparent resistivity and apparent charge rate inversion objective function is: ； Where g is the theoretical AC electric field data matrix, d is the measured AC electric field data matrix, m is the model resistivity matrix or charge rate matrix, and W is the theoretical AC electric field data matrix. d is the weight coefficient matrix; in order to make S(m) converge, the resistivity or charging rate m is modified multiple times during inversion, and the modification relationship is: ； Where J is the Jacobi matrix, J T is the transposed matrix of J, is the damping factor, is represented as the identity matrix.

6. The method for parallel advance detection of multi-frequency alternating current by shield tunneling in coal mine tunnels according to claim 4, characterized in that: During the forward construction of the shield machine, the shield machine anchor drill constructs a control point at a certain distance; the power supply-measurement electrode group and multi-frequency parallel electrical instrument of all the control points at the rear are moved forward together. The moving interval and the number of control points are related to the excavation progress of the day. Control point A1 is the measuring point closest to the working face.

7. A multi-frequency AC parallel advance detection system for shield tunneling in coal mines, characterized in that: The method for parallel advance detection of multi-frequency alternating current by shield tunneling in a coal mine tunnel according to any one of claims 1 to 6 comprises: The observation system module is used to deploy a three-directional data observation system in the tunnel excavation direction; The potential and phase acquisition module is used to collect the three-directional potential difference amplitude and three-directional potential difference phase values ​​of the deployed three-directional data observation system using a multi-frequency pseudo-random electric dipole source emission mode; The apparent resistivity and apparent charge rate module is used to input the acquired three-directional potential difference amplitude and potential difference phase values ​​into professional software based on the Cole-Cole model for inversion, thereby obtaining a three-dimensional apparent resistivity image and a three-dimensional apparent charge rate image. The joint determination module is used to jointly determine the water-rich anomaly based on the three-dimensional apparent resistivity image and the three-dimensional apparent charge rate image.

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