Three-dimensional direct current method lane hole joint detection method and system

Abstract

The invention belongs to the technical field of mine geophysical prospecting, and particularly relates to a three-dimensional direct current method roadway hole combined detection method and system. Firstly, a target drill hole and a roadway measuring line are combined to design a three-dimensional long measuring line; constructing a three-dimensional geologic model and establishing a space coordinate system according to the three-dimensional long measuring line, the mine laneway and the space structure of the stope face, installing an instrument and an electrode in the three-dimensional long measuring line, performing pole shifting to acquire voltage and current data, and calculating apparent resistivity data of the stope face of the mine laneway according to the acquired voltage and current data; performing three-dimensional resistivity inversion fitting calculation on the apparent resistivity data to generate an inversion three-dimensional resistivity data volume; and finally, the inversion three-dimensional resistivity data volume is analyzed, resistivity distribution conditions in different time periods are obtained, and the migration change condition of the water body of the stope face is speculated according to the change condition of the resistivity distribution along with time. The problem that a mine direct current electric method in the prior art still lacks the accuracy of water disaster abnormity monitoring can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of mine geophysical exploration, and in particular relates to a three-dimensional direct current electrical method for combined tunnel and hole detection and a system. Background Art

[0002] At present, the hydrogeological conditions of many coalfields are relatively complex, and they are threatened by various water bodies during coal mining. Among them, the prevention and control of water inrush from the coal seam floor has attracted much attention. The detection and research on the destruction and development law of the floor rock strata after coal seam mining has always been a very concerned issue in coal mine safety production. After coal seam mining, the stress of the floor is rebalanced, which will result in displacement, deformation and even destruction of the floor rock mass.

[0003] The existing research on the destruction of each layer of the mining floor has proposed the "lower three zones" theory, that is, from the bottom of the coal seam to the top of the aquifer, it is divided into: the floor water-conducting destruction zone, the effective aquiclude protection zone, and the pressure-bearing water-conducting lifting zone. The coal seam floor is affected by the mining pressure, the continuity of the rock layer is destroyed, and its water conductivity is significantly changed due to the generation of cracks. The spatial distribution range of the cracks that cause the water conductivity to change significantly is called the water-conducting destruction zone, and the normal distance from the bottom of the mining coal seam to the deepest boundary of the water-conducting crack distribution is called the "water-conducting destruction zone depth". There are generally three types of cracks in the rock strata of the water-conducting destruction zone: 1. Vertical tension cracks, distributed in the uppermost part of the floor close to the coal seam, are tension cracks formed by the layer tension failure when the floor expands. 2. Layer cracks, mainly appear in the form of delamination along the layer surface, generally more developed in the shallow part of the floor, which is caused by the delamination along the layer weak structure surface due to the reverse displacement of compression-expansion-recompression under the action of mine pressure during the advancement of the coal mining working face. 3. Shear fractures, generally in two groups, are distributed in opposite directions at an angle of about 60°. They are formed by the reverse shearing of the rock layers between the goaf and the coal wall (and the re-compression zone of the goaf roof). These three types of fractures intersect with each other without obvious boundaries. When they are connected with the aquifer (or the pressure water conduction zone or the water-conducting fault), water inrush from the bottom plate may occur.

[0004] Therefore, accurately determining the depth of floor mining damage is the primary condition for accurately predicting the water-blocking capacity of the floor. Especially in the mining of coal seams that are seriously threatened by water damage in the coal seam floor, more attention should be paid to the testing and analysis of the floor damage law after mining. How to accurately grasp the floor damage depth and its characteristics during the mining process of the mining face, obtain the corresponding technical parameters, carry out water prevention and control work on the working face, eliminate the threat of water inrush, and ensure the safe and reasonable mining of the working face has important guiding significance.

[0005] Conventional methods for detecting floor damage include drilling water injection, stress-strain measurement, and geophysical measurement. These methods are either troublesome to construct or have a long construction process, and cannot reflect the floor conditions in real time. Moreover, they are not sensitive to or even unresponsive to water anomalies, and cannot be used as a means of monitoring water anomalies in coal seams above pressurized water. Mine DC resistivity exploration is an important branch of mine geophysical exploration. It is based on the difference in rock conductivity and studies mine geological problems by measuring and analyzing the distribution and change laws of stable current fields near tunnels and mining areas. Since fault structures, rock porosity, water content and mineralization, external pressure, temperature, etc. have a great influence on rock conductivity, mine DC electrical method is widely used in mining area structural detection and prediction of geological disasters such as mine water inrush, gas outburst, and impact mine pressure.

[0006] The existing mine DC method still lacks accuracy in monitoring abnormal water hazards and needs to be improved. Summary of the invention

[0007] The technical problem solved by the present invention is to provide a three-dimensional direct current electrical method for joint detection of tunnels and holes and a system thereof, so as to solve the problem that the direct current electrical method in mines in the prior art still lacks accuracy in monitoring abnormal water hazards.

[0008] The basic solution provided by the present invention: a three-dimensional direct current electrical method for laneway and hole joint detection method, comprising:

[0009] S1: Select the target borehole according to the mining face structure of the mine tunnel, and design a three-dimensional long survey line by combining the target borehole with the tunnel survey line;

[0010] S2: Construct a 3D geological model and establish a spatial coordinate system based on the 3D long survey line, mine tunnels and mining working face spatial structure, install instruments and electrodes in the 3D long survey line, call the preset electrode arrangement and the preset device arrangement to run the electrode, collect voltage and current data, and calculate the apparent resistivity data based on the collected voltage and current data

[0011] S3: Perform three-dimensional resistivity inversion fitting calculation on the apparent resistivity data to generate an inverted three-dimensional resistivity data volume;

[0012] S4: Analyze the inverted three-dimensional resistivity data volume to obtain the resistivity distribution in different time periods, and infer the migration changes of water bodies in the mining working face based on the changes in resistivity distribution over time.

[0013] Further, the S1 includes:

[0014] S1-1: Obtain the structural data of the target mine tunnel and mining face, and lay out the working face drift and drilling holes;

[0015] S1-2: Lay out survey lines in the working face trench and in the borehole, and connect the survey lines of the borehole and the working face trench through large lines to form a three-dimensional long survey line.

[0016] Furthermore, the working face chute includes a transport chute and a return air chute, the drill hole includes an upper drill hole and a lower drill hole, the main line is composed of electrodes connected in series, the upper drill hole is connected with the transport chute, and the main line in the upper drill hole and the transport chute main line constitute an upward main line; the lower drill hole is connected with the return air chute, and the main line of the lower drill hole and the return air chute main line constitute a downward main line.

[0017] Further, the S2 includes:

[0018] S2-1: Connect the uplink and downlink cables to the host device through transition cables respectively;

[0019] S2-2: Obtain geological data of the target mine tunnel mining face, construct a three-dimensional geoelectric model, and import the three-dimensional long survey line structure into the three-dimensional geoelectric model;

[0020] S2-3: performing traversal measurement of all electrodes according to a preset electrode arrangement and a preset device arrangement, and collecting voltage and current data;

[0021] S2-4: Build an electrode coordinate system based on the three-dimensional long survey line structure of the three-dimensional geoelectric model, obtain the device coefficient, and calculate the apparent resistivity data of the mine tunnel mining face in combination with the collected voltage and current data.

[0022] Further, the S2-4 includes:

[0023] S2-4-1: Build an electrode coordinate system according to the electrode arrangement, select any two electrodes as power supply electrodes A and B, and supply power to the ground with +I and -I respectively. Then select two electrodes M and N between A and B to form a four-electrode device; the midpoint formed by the connection between M and N coincides with the straight line connecting A and B, and the electrode at the midpoint formed by the connection between M and N is used as the measuring electrode to collect potential difference data;

[0024] S2-4-2: Based on the power supply current of the power supply electrode, the device coefficient of the four-electrode device, and the potential difference data measured by the measuring electrode, the apparent resistivity data within the exploration range of the mine tunnel mining face is calculated. The calculation formula is:

[0025]

[0026] Among them, ρ s represents apparent resistivity, K represents device coefficient, I represents supply current, ΔU MN Indicates potential difference.

[0027] Further, the S3 includes:

[0028] S3-1: Segment the three-dimensional geoelectric model according to the calculated apparent resistivity data to form a three-dimensional apparent resistivity data volume;

[0029] S3-2: Calculate the residual between the measured value and the calculated value of the three-dimensional apparent resistivity data body based on forward calculation, then invert the Jacobian matrix to calculate the correction amount of the resistivity parameter, and determine whether the residual between the measured value and the calculated value reaches the preset accuracy;

[0030] S3-3: If it is achieved, the three-dimensional resistivity data volume and image model are output; if it is not achieved, the resistivity parameters in the apparent resistivity data are modified.

[0031] The three-dimensional direct current electrical method lane-hole joint detection system is applied to the above three-dimensional direct current electrical method lane-hole joint detection method, comprising:

[0032] The 3D long survey line layout module is used to select the target borehole according to the mining face structure of the mine tunnel, and jointly design the 3D long survey line by combining the target borehole with the tunnel survey line;

[0033] Equipment deployment module, used to install instruments and electrodes in long three-dimensional survey lines;

[0034] A data acquisition module is used to call a preset electrode arrangement mode and a preset device arrangement mode according to the laid-out electrodes to run the electrodes and collect voltage and current data;

[0035] The apparent resistivity calculation module is used to calculate the apparent resistivity data of the mine tunnel mining face based on the collected voltage and current data;

[0036] The inversion module is used to construct a three-dimensional geoelectric model, perform three-dimensional resistivity inversion fitting calculation on the apparent resistivity data, and generate an inverted three-dimensional resistivity data volume;

[0037] The analysis module is used to invert the three-dimensional resistivity data volume for analysis, obtain the resistivity distribution characteristics of different time periods, and the water displacement change data of the mining working face in the mine tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a flowchart of an embodiment of the present invention;

[0039] Figure 2 A schematic diagram of the survey line layout according to an embodiment of the present invention;

[0040] Figure 3 A schematic diagram of the connection between a host and electrodes according to an embodiment of the present invention;

[0041] Figure 4A schematic diagram of a three-dimensional monopole-monopole electrode arrangement according to an embodiment of the present invention;

[0042] Figure 5 A schematic diagram of a three-dimensional monopole-dipole electrode arrangement according to an embodiment of the present invention;

[0043] Figure 6 A schematic diagram of a three-dimensional dipole-dipole electrode arrangement according to an embodiment of the present invention;

[0044] Figure 7 A schematic diagram of a Wenner arrangement according to an embodiment of the present invention;

[0045] Figure 8 Schematic diagram of electric field distribution according to an embodiment of the present invention;

[0046] Fig. 9 A schematic diagram of a four-stage device according to an embodiment of the present invention;

[0047] Fig.10 This is a diagram of the three-dimensional geoelectric model inversion results of an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The following is further described in detail through specific implementation methods:

[0049] The embodiment is basically as shown in the attached Figure 1 As shown: A three-dimensional direct current electrical method for detecting lane holes, including:

[0050] S1: Select the target borehole according to the mining face structure of the mine tunnel, and design a three-dimensional long survey line by combining the target borehole with the tunnel survey line; S1 includes:

[0051] S1-1: Obtain the target mine tunnel mining face structure data, and lay out the face drift and drilling holes;

[0052] S1-2: Survey lines are laid out in the working face chute and in the borehole, and the survey lines of the borehole and the working face chute are connected by a large line to form a three-dimensional long survey line; the working face chute includes a transport chute and a return air chute, the borehole includes an upper borehole and a lower borehole, the large line is composed of electrodes connected in series, the upper borehole is connected with the transport chute, and the large line in the upper borehole and the transport chute large line form an upward large line; the lower borehole is connected with the return air chute, and the large line of the lower borehole and the large line of the return air chute form a downward large line.

[0053] In this embodiment, the three-dimensional long measuring line composed of the borehole and the working face slot is as follows: Figure 2 As shown, Figure 2The enclosed area is a bird's-eye view of the mining face of the mine tunnel. In this view, the auxiliary transport tunnel is used to serve the transportation of personnel, materials and equipment in the entire mine. The upper half of the view, namely the transport chute and the upper drill hole, constitute the upward line, and the lower half, namely the return air chute and the lower drill hole, constitute the downward line. Both the upward line and the downward line are connected to the main machine, thus forming a long survey line. In this long survey line, the survey line of each area is not restricted by height and may not be on the same plane. For example, Fig.10 As shown, the opening height and direction of the upper borehole are not in the same plane as the opening height and direction of the lower borehole, thus forming a three-dimensional long survey line.

[0054] As for the definition of the big line, Figure 3 As shown, in the high-density electrical method, the cable connecting the electrodes in series is called a large line, and each large line is evenly distributed with 10 distributed switches, which are numbered 1-10 from the beginning to the end. The distributed switch is connected to the plug-in card of the electrode, which means that each large line can be connected to 10 electrodes. The large lines are connected in series through cascade electrode converters. Therefore, the three-dimensional long measurement line in this application can include multiple large lines to form an uplink large line and a downlink large line, and the uplink large line and the downlink large line are respectively connected to the host through transition cables, specifically:

[0055] S2: construct a three-dimensional geoelectric model based on the three-dimensional long survey line structure and the geological data of the mine tunnel recovery working face, install instruments and electrodes in the three-dimensional long survey line, call the preset electrode arrangement method and the preset device arrangement method to run the electrode, collect voltage and current data, and calculate the apparent resistivity data of the mine tunnel recovery working face based on the collected voltage and current data; wherein, S2 includes:

[0056] S2-1: Connect the uplink and downlink cables to the host device through transition cables respectively;

[0057] S2-2: Obtain geological data of the target mine tunnel mining face, construct a three-dimensional geoelectric model, and import the three-dimensional long survey line structure into the three-dimensional geoelectric model;

[0058] S2-3: Perform traversal measurement of all electrodes according to a preset electrode arrangement and a preset device arrangement, and collect voltage and current data;

[0059] S2-4: Build an electrode coordinate system based on the three-dimensional long survey line structure of the three-dimensional geoelectric model, obtain the device coefficient, and calculate the apparent resistivity data of the mine tunnel mining face in combination with the collected voltage and current data.

[0060] like Figure 3As shown, in the high-density electrical method, the electrodes are connected in series to form a large line, and the large lines are connected to each other through cascade electrode converters to form an upward large line or a downward large line. The upward large line and the downward large line are then connected to the host through a transition cable.

[0061] After the host device and electrodes are laid out, the three-dimensional space coordinates are established according to the geological data of the mining face of the mine tunnel. After the three-dimensional space coordinates are constructed, the electrodes are numbered and the three-dimensional coordinate points are defined according to the spatial positions of the electrodes in the three-dimensional long measurement line. Figure 2 As shown in the figure, the electrode at the far end of the upper borehole is electrode No. 1, and the coordinate point is defined as (x 1 ,y 1 , z 1 ), the electrode at the far end of the lower borehole is the largest electrode, and the coordinate point is defined as (x k ,y k , z k ).

[0062] Then, the traversal is performed according to the preset electrode arrangement and the preset device arrangement. In this embodiment, the electrode arrangement includes the following three types: Figure 4 A schematic diagram of a three-dimensional monopole-monopole arrangement is shown in FIG. Figure 5 The schematic diagram of the three-dimensional monopole-dipole arrangement is shown in Figure 6 The three-dimensional dipole-dipole arrangement schematic diagram shown in the figure is used in this application.

[0063] Then the device arrangement is preset. In the present application, there can be as many as 16 device arrangements consisting of three electrode arrangements, namely Wenner arrangement, dipole arrangement, differential arrangement, coupled arrangement A, coupled arrangement B, AM arrangement, AMN arrangement, ABM arrangement, ABMN arrangement, MNB arrangement, Schlumberger arrangement, self-electrode M, self-electrode MN, charge M, charge MN arrangement and cross-hole dipole arrangement.

[0064] In this embodiment, the Wenner arrangement is used for running. Figure 7 As shown, AM=MN=NB is an electrode spacing, A, B, M, N move rightward point by point at the same time to obtain the first layer of profile lines, then AM, MN, NB increase an electrode spacing, A, B, M, N move rightward point by point at the same time to obtain the second layer of profile lines; the measurement is repeated in this way, and finally an inverted trapezoidal profile line is obtained.

[0065] Therefore, the above-mentioned electrode arrangement and device arrangement are used, and then the apparent resistivity data of the mine tunnel mining face is calculated based on the measured voltage and current data, specifically:

[0066] Step 1: Build an electrode coordinate system according to the electrode arrangement, select any two electrodes as power supply electrodes A and B, and supply power to the ground with +I and -I respectively. Then select two electrodes M and N between A and B to form a four-electrode device; the midpoint formed by the connection between M and N coincides with the straight line connecting A and B, and the electrode at the midpoint formed by the connection between M and N is used as the measuring electrode to collect potential difference data;

[0067] like Figure 8 As shown, first assume that in a uniform isotropic infinite medium with a resistivity of ρ, there are electrode power sources A and B, which are 2L apart and supply power to the ground with +I and -I respectively. According to the superposition principle of electric field, the potential formed by A and B at point M can be obtained:

[0068]

[0069] Under ideal conditions, the three-dimensional dipole-dipole electrode arrangement and the Wenner arrangement of the device used in this application are in an infinite uniform dielectric half space, and power is supplied by any two electrodes A and B, and the potential difference is measured by any two electrodes M and N. Then:

[0070]

[0071] At the same time, the calculation method of uniform earth resistivity is:

[0072]

[0073] Where K is the device coefficient, which depends on the spatial arrangement of the electrodes. However, in practical applications, considering that a large number of electrodes are laid at one time to collect a large amount of data, the power supply electrodes and the measuring electrodes are usually placed in a straight line to facilitate subsequent data processing;

[0074] When it is difficult to achieve the ideal state conditions in actual situations, the underground medium of the mining face is not uniform, and the geological conditions are extremely complex due to the undulating terrain, overlapping and interlacing of various rocks, the existence of faults and fissures, etc. At this time, the resistivity value measured is a comprehensive reflection of the resistivity of all media within the exploration volume of the mining face, that is, the apparent resistivity calculated as required by this application, as described in the following step 2;

[0075] Step 2: Calculate the apparent resistivity data within the exploration range of the mine tunnel mining face according to the power supply current of the power supply electrode, the device coefficient of the four-electrode device, and the potential difference data measured by the measuring electrode. The calculation formula is:

[0076]

[0077] Among them, ρ s represents apparent resistivity, K represents device coefficient, I represents supply current, ΔUMN Indicates potential difference.

[0078] S3: Perform three-dimensional resistivity inversion fitting calculation on the apparent resistivity data to generate an inverted three-dimensional resistivity data volume; wherein S3 includes:

[0079] S3-1: Segment the three-dimensional geoelectric model according to the calculated apparent resistivity data to form a three-dimensional apparent resistivity data volume;

[0080] S3-2: Calculate the residual between the measured value and the calculated value of the three-dimensional apparent resistivity data body based on forward calculation, then invert the Jacobian matrix to calculate the correction amount of the resistivity parameter, and determine whether the residual between the measured value and the calculated value reaches the preset accuracy;

[0081] S3-3: If it is achieved, the three-dimensional apparent resistivity data volume and image model are output; if it is not achieved, the resistivity parameters in the apparent resistivity data are modified, and step S3-2 is repeated until the preset calculation accuracy is reached.

[0082] like Fig.10 As shown in the figure, according to the three-dimensional apparent resistivity data volume formed by segmenting the three-dimensional geoelectric model, a forward calculation is first performed. Specifically, in the three-dimensional coordinate system formed by the three-dimensional apparent resistivity data volume, it is assumed that the field source is located at point (x 0 ,y 0 , z 0 ), and the supply current intensity is I, then the potential differential of the current field generated by it satisfies the following formula:

[0083]

[0084] Its boundary condition equation is:

[0085] Ground z = 0;

[0086] Other boundaries;

[0087] In the above formula, σ(x, y, z) represents the conductivity of the underground medium, n is the coordinate variable in the direction of the normal line outside the boundary; θ is the angle between n and r; r is the radial direction from the source point to the point on the boundary, and n is the unit vector in the direction of the normal line outside the boundary. In this case, the electric field and conductivity of the underground medium are functions of three-dimensional space, that is, U = U(x, y, z) and σ = σ(x, y, z).

[0088] The finite difference method is used to solve the potential differential of the above current field to calculate the residual between the measured value and the calculated value of the three-dimensional apparent resistivity data body, and then the inversion method is used for calculation. In this application, the inversion method is calculated based on the smoothing constrained least squares method. The process is: first, it is assumed that the inverted apparent resistivity model is composed of many rectangular blocks with constant resistivity values, and then the resistivity value of each small block is determined by an iterative nonlinear optimization method. In this process, the smoothing constrained least squares method is used, and finally the result is that the obtained resistivity value will be very close to the actual measured apparent resistivity value; specifically:

[0089] The smoothness constrained least squares method is based on the following equation:

[0090]

[0091] Where J is the Jacobian partial differential matrix, λ is the damping factor, and C is the two-dimensional smoothing filter factor. is the deviation vector of the logarithmic difference between the measured apparent resistivity and the calculated apparent resistivity, is the correction vector for the model parameters.

[0092] The smooth constrained least squares method uses the following objective function to minimize:

[0093]

[0094] In the formula, i is the number of iterations; g i is the logarithmic difference between the observed apparent resistivity and the model response apparent resistivity; i is the damping factor; r i is the model parameter vector; C is the smoothing filter.

[0095] The gradient of the objective function can be expressed as:

[0096]

[0097] Smooth constrained least squares involves solving the following system of linear equations:

[0098]

[0099] Where Ji is the Jacobian matrix, i.e., the partial derivative matrix of apparent resistivity and model resistivity, p i is the modification vector of the model parameters.

[0100] Then use the finite difference method or finite element method to calculate the point source field potential. Therefore, when doing forward calculation, the potential of all grid nodes when the power supply current is taken as unit current is calculated in turn at each power supply node and measurement node, and the apparent resistivity ρ of any electrode device can be calculated. s The Jacobian matrix of .

[0101] S4: Analyze the inverted three-dimensional resistivity data body to obtain the resistivity distribution in different time periods, and infer the migration change of the water body in the mining working face according to the change of the resistivity distribution over time; in this embodiment, the generated inverted three-dimensional resistivity data body can obtain the resistivity distribution closest to the actual geological conditions, and according to the obtained inverted three-dimensional resistivity data body, the inverted three-dimensional resistivity data bodies of different time periods are compared to observe the trend of resistivity change, wherein the existence and movement of water bodies will affect the resistivity value, therefore, the position and migration of the water bodies can be inferred through the comparison results.

[0102] Then, the inferred location and movement of the water body are correlated with time, and a time series diagram of the water body movement is drawn, so that users can understand the laws of water body activity and then discover and predict potential geological disaster risks. Finally, based on the above analysis results, this application also generates an analysis report and gives specific recommended measures in the report, such as whether it is necessary to strengthen the drainage system or adjust the mining plan, so that users can make decisions in a timely manner.

[0103] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A three-dimensional direct current electrical method for joint detection of tunnel holes, characterized in that: include: S1: Select the target borehole according to the mining face structure of the mine tunnel, and design a three-dimensional long survey line by combining the target borehole with the tunnel survey line; S2: construct a three-dimensional geoelectric model based on the three-dimensional long survey line structure and the geological data of the mine tunnel mining face, install instruments and electrodes in the three-dimensional long survey line, call the preset electrode arrangement method and the preset device arrangement method to run the electrode, collect voltage and current data, and calculate the apparent resistivity data of the mine tunnel mining face based on the collected voltage and current data; S3: Perform three-dimensional resistivity inversion fitting calculation on the apparent resistivity data to generate an inverted three-dimensional resistivity data volume; S4: Analyze the inverted three-dimensional resistivity data volume to obtain the resistivity distribution characteristics of different time periods and the water displacement change data of the mine tunnel mining face.

2. The three-dimensional direct current electrical method for laneway joint detection according to claim 1 is characterized in that: The S1 includes: S1-1: Obtain the target mine tunnel mining face structure data, and lay out the face drift and drilling holes; S1-2: Lay out survey lines in the working face trench and in the borehole, and connect the survey lines of the borehole and the working face trench through large lines to form a three-dimensional long survey line.

3. The three-dimensional direct current electrical method for laneway joint detection according to claim 2 is characterized in that: The working face chute includes a transport chute and a return air chute, the drill hole includes an upper drill hole and a lower drill hole, the main line is composed of electrodes connected in series, the upper drill hole is connected with the transport chute, and the main line in the upper drill hole and the main line in the transport chute form an upward main line; the lower drill hole is connected with the return air chute, and the main line in the lower drill hole and the main line in the return air chute form a downward main line.

4. The three-dimensional direct current electrical method for laneway joint detection according to claim 3 is characterized in that: The S2 includes: S2-1: Connect the uplink and downlink cables to the host device through transition cables respectively; S2-2: Obtain geological data of the target mine tunnel mining face, construct a three-dimensional geoelectric model, and import the three-dimensional long survey line structure into the three-dimensional geoelectric model; S2-3: performing traversal measurement of all electrodes according to a preset electrode arrangement and a preset device arrangement, and collecting voltage and current data; S2-4: Build an electrode coordinate system based on the three-dimensional long survey line structure of the three-dimensional geoelectric model, obtain the device coefficient, and calculate the apparent resistivity data of the mine tunnel mining face in combination with the collected voltage and current data.

5. The three-dimensional direct current electrical method for laneway joint detection according to claim 4 is characterized in that: The S2-4 includes: S2-4-1: Build an electrode coordinate system according to the electrode arrangement, select any two electrodes as power supply electrodes A and B, and supply power to the ground with +I and -I respectively. Then select two electrodes M and N between A and B to form a four-electrode device; the midpoint formed by the connection between M and N coincides with the straight line connecting A and B, and the electrode at the midpoint formed by the connection between M and N is used as the measuring electrode to collect potential difference data; S2-4-2: Based on the power supply current of the power supply electrode, the device coefficient of the four-electrode device, and the potential difference data measured by the measuring electrode, the apparent resistivity data within the exploration range of the mine tunnel mining face is calculated. The calculation formula is: Among them, ρ s represents apparent resistivity, K represents device coefficient, I represents supply current, ΔU MM Indicates potential difference.

6. The three-dimensional direct current electrical method for joint detection of lane holes according to claim 5 is characterized in that: The S3 includes: S3-1: Segment the three-dimensional geoelectric model according to the calculated apparent resistivity data to form a three-dimensional apparent resistivity data volume; S3-2: Calculate the residual between the measured value and the calculated value of the three-dimensional apparent resistivity data body based on forward calculation, then invert the Jacobian matrix to calculate the correction amount of the resistivity parameter, and determine whether the residual between the measured value and the calculated value reaches the preset accuracy; S3-3: If it is achieved, the three-dimensional resistivity data volume and image model are output; if it is not achieved, the resistivity parameters in the apparent resistivity data are modified.

7. A three-dimensional direct current electrical method lane-hole joint detection system, applied to the above three-dimensional direct current electrical method lane-hole joint detection method, characterized in that: include: The 3D long survey line layout module is used to select the target borehole according to the mining face structure of the mine tunnel, and jointly design the 3D long survey line by combining the target borehole with the tunnel survey line; Equipment deployment module, used to install instruments and electrodes in long three-dimensional survey lines; A data acquisition module is used to call a preset electrode arrangement mode and a preset device arrangement mode according to the laid-out electrodes to run the electrodes and collect voltage and current data; The apparent resistivity calculation module is used to calculate the apparent resistivity data of the mine tunnel mining face based on the collected voltage and current data; The inversion module is used to construct a three-dimensional geoelectric model, perform three-dimensional resistivity inversion fitting calculation on the apparent resistivity data, and generate an inverted three-dimensional resistivity data volume; The analysis module is used to invert the three-dimensional resistivity data volume for analysis, obtain the resistivity distribution in different time periods, and analyze the migration changes of water bodies in the mining working face based on the changes in resistivity distribution over time.

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