Mine roof water disaster monitoring method based on induced polarization method and related equipment

Abstract

The application provides a mine roof water disaster monitoring method based on the induced polarization method and related equipment, and two drilling modes are provided according to the development position of the water flowing fractured zone on the mine roof: when the water flowing fractured zone develops to the ground, vertical drilling is selected on the side close to the ground of the mine roof, the electrode string arranged in the drilling is more easily avoided from the caving zone in the mine roof, the drilling difficulty is reduced, and the drilling cost is saved while the monitoring accuracy is ensured; and when the water flowing fractured zone does not develop to the ground, drilling with a certain angle is selected on the side close to the working face of the mine roof, the electrode string can enter the water flowing fractured zone when the drilling depth is shallow, accurate monitoring data of the electrode string are obtained, the drilling difficulty is reduced, and the drilling cost is saved. Then, the apparent resistivity and the apparent polarization rate of the surrounding rock of the mine roof are monitored in real time through the electrode string, and the water inrush of the coal seam roof is quickly and accurately monitored.

Description

Technical Field

[0001] This application relates to the field of coal mine water control and safety technology, and in particular to a method and related equipment for monitoring water hazards on the mine roof based on induced polarization method. Background Technology

[0002] During coal mining, the deformation and collapse of the roof caused by coal seam excavation create fissures that develop towards the surface, forming water-conducting fracture zones. When these fracture zones extend to the aquifer or even the surface, they form one or more water-conducting channels connecting the coal face to the aquifer or surface. Water then flows into the goaf along these channels, often leading to water-related accidents. These accidents, due to their suddenness and destructive nature, pose a significant threat to the lives and property of coal miners and workers, making coal mine water hazards a major issue affecting safe coal production. The formation and occurrence of mine water hazards go through a process of gestation, development, and eventual occurrence. Each stage of this process has its corresponding precursors. If, in the daily water prevention and control work of coal mines, the hydrogeological conditions of each aquifer and the mining situation of the working face are monitored in real time, the dynamic situation of mine hydrology can be grasped in a timely manner, and dangerous signs can be detected in time and corresponding preventive measures can be taken. This can achieve early detection, early prediction, and early prevention of mine water hazard accidents, ensuring the safe and normal production of coal mines. Therefore, the determination of the spatial location and on-site layout of monitoring equipment is the key to whether the monitoring and early warning system can successfully predict water disasters.

[0003] In the coal mining sector, current methods for monitoring roof water hazards include microseismic monitoring, high-density electrical resistivity tomography (EDT), or monitoring of surrounding rock pressure and deformation. However, microseismic and EDT methods often generate limited data and are subject to numerous interfering factors, while surrounding rock pressure and deformation are not directly correlated with water inrush. This can lead to unreliable monitoring results and introduce unpredictable factors. Furthermore, the spatial layout of the monitoring equipment is not designed based on the specific conditions of the borehole, making the equipment prone to damage and resulting in significant detection errors. Summary of the Invention

[0004] In view of this, the purpose of this application is to propose a method and related equipment for monitoring water hazards on the mine roof based on induced polarization.

[0005] To achieve the above objectives, the first aspect of this application provides a method for monitoring mine roof water hazards based on induced polarization, comprising:

[0006] The location of the water-conducting fracture zone within the mine roof is determined;

[0007] In response to the development of the water-conducting fracture zone to the surface, first borehole data is determined on the side of the mine roof near the surface; based on the first borehole data, multiple surface monitoring boreholes are drilled in the mine roof in a direction perpendicular to the plane of the surface; or,

[0008] In response to the fact that the water-conducting fracture zone has not developed to the surface, second borehole data is determined on the side of the mine roof near the working face; based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between each underground monitoring borehole and the plane containing the lower surface of the mine roof is the inclination angle.

[0009] The presence of water inrush around the mine roof is determined based on the apparent resistivity and apparent polarizability acquired in real time by the electrode string.

[0010] The second aspect of this application provides a mine roof water hazard monitoring device based on induced polarization method, characterized in that it includes:

[0011] Data acquisition module: Acquires the development location of the water-conducting fracture zone within the mine roof;

[0012] The drilling module is configured to: in response to the development of the water-conducting fracture zone to the surface, determine first borehole data on the side of the mine roof near the surface; and based on the first borehole data, drill multiple surface monitoring boreholes in the mine roof in a direction perpendicular to the plane of the surface; or,

[0013] In response to the fact that the water-conducting fracture zone has not developed to the surface, second borehole data is determined on the side of the mine roof near the working face; based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between each underground monitoring borehole and the plane containing the lower surface of the mine roof is the inclination angle.

[0014] The monitoring module is configured to determine whether there is a water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode strings deployed in the ground monitoring borehole or the underground monitoring borehole.

[0015] A third aspect of this application provides an electronic device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method provided in the first aspect of this application.

[0016] A fourth aspect of this application provides a non-transitory computer-readable storage medium storing computer instructions for causing a computer to perform the method provided in the first aspect of this application.

[0017] The fifth aspect of this application provides a mine roof water hazard monitoring system based on induced polarization method, characterized in that it includes a general monitoring substation, a control unit, an electrode string, and the electronic equipment described in the third aspect of this application:

[0018] The electronic device is configured to: acquire the development location of the water-conducting fracture zone within the mine roof; and, in response to the water-conducting fracture zone developing to the surface, determine first borehole data on the side of the mine roof near the surface; based on the first borehole data, open multiple surface monitoring boreholes in the mine roof in a direction perpendicular to the plane where the surface is located; or, in response to the water-conducting fracture zone not developing to the surface, determine second borehole data on the side of the mine roof near the working face; and, based on the second borehole data, open multiple underground monitoring boreholes on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between each underground monitoring borehole and the plane containing the lower surface of the mine roof is the inclination angle.

[0019] The electrode strings are deployed in the surface monitoring borehole or the downhole monitoring borehole, wherein each electrode string is connected to the smart electrodes by a fixed-point distributed optical cable, and the electrode strings are configured to: acquire the apparent resistivity and apparent polarization around the surface monitoring borehole or the downhole monitoring borehole in real time;

[0020] The sub-controller is connected to the electrode string and is configured to: control the electrode string to perform high-density excitation polarization measurement on the surface monitoring borehole or the area around the underground monitoring borehole in the mine roof;

[0021] The monitoring general substation is connected to the sub-control unit and is configured to: send control signals to the sub-control unit and collect the apparent resistivity and apparent polarization sent by multiple electrode strings;

[0022] The electronic device is connected to the general monitoring substation and is also configured to: determine whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode strings deployed in the ground monitoring borehole or the underground monitoring borehole.

[0023] As can be seen from the above, the mine roof water hazard monitoring method and related equipment based on induced polarization provided in this application offer two drilling methods depending on the development location of the water-conducting fracture zone on the mine roof: when the water-conducting fracture zone develops to the surface, vertical drilling is performed on the side of the mine roof closer to the surface. This ensures monitoring accuracy while making it easier for the electrode string deployed in the borehole to avoid the collapse zone located in the mine roof, thereby reducing drilling difficulty and saving drilling costs. When the water-conducting fracture zone has not developed to the surface, drilling is performed at a certain angle on the side of the mine roof closer to the working face. Drilling on the side closer to the working face allows the electrode string to enter the water-conducting fracture zone when the drilling depth is shallow, enabling the electrode string to obtain accurate monitoring data. At the same time, reducing the drilling depth also reduces drilling difficulty and saves drilling costs. This application reduces malfunctions and interference caused by the installation of smart electrodes by installing electrode strings in each surface or underground monitoring borehole in a single step. It enables real-time monitoring of the apparent resistivity and apparent polarizability of the rock surrounding the mine roof. When water inrush occurs in the mine roof, the changes in the apparent resistivity and apparent polarizability of the surrounding rock are the first signs. Apparent resistivity and apparent polarizability are parameters directly related to water inrush. Therefore, it can quickly and accurately monitor the water inrush situation in the coal seam roof. Furthermore, each electrode string uses high-strength, shear-resistant, fixed-point distributed optical cables to connect the smart electrodes, improving the connection strength between the smart electrodes and preventing easy breakage. Even if a break occurs, some smart electrodes can still transmit data. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a mine roof water hazard monitoring method based on induced polarization method, as described in an embodiment of this application.

[0026] Figure 2 This is a cross-sectional schematic diagram of the ground monitoring borehole layout in an embodiment of this application;

[0027] Figure 3 This is a cross-sectional schematic diagram of the layout of downhole monitoring boreholes in an embodiment of this application;

[0028] Figure 4 A flowchart for determining the first borehole data in an embodiment of this application;

[0029] Figure 5 This is a schematic diagram of the horizontal plane layout of the ground monitoring boreholes in an embodiment of this application;

[0030] Figure 6 This is a flowchart illustrating the determination of second borehole data according to an embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the horizontal plane layout of the downhole monitoring boreholes in an embodiment of this application;

[0032] Figure 8 A flowchart illustrating monitoring based on ground monitoring boreholes is provided for embodiments of this application;

[0033] Figure 9 A flowchart illustrating monitoring based on downhole monitoring boreholes is provided for embodiments of this application;

[0034] Figure 10 The process for determining the location of water-conducting fracture zones in the embodiments of this application;

[0035] Figure 11 This is a schematic diagram of the structure of a mine roof water hazard monitoring device based on the induced polarization method according to an embodiment of this application;

[0036] Figure 12 This is a schematic diagram of the structure of the electronic device according to an embodiment of this application;

[0037] Figure 13 This is a schematic diagram of the structure of a mine roof water hazard monitoring system based on induced polarization method, which involves drilling on one side of the ground according to an embodiment of this application.

[0038] Figure 14 This is a schematic diagram of the structure of a mine roof water hazard monitoring system based on induced polarization method, which involves drilling on one side of the well in accordance with an embodiment of this application.

[0039] Figure 15 This is a schematic diagram of the structure of the electrode string inside the borehole according to an embodiment of this application;

[0040] Figure 16 This is a schematic diagram of the structure of the smart electrode in an embodiment of this application;

[0041] Figure 17 This is a schematic diagram of the structure of a general monitoring substation in an embodiment of this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0043] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0044] For a water inrush to occur in a mine roof, three necessary conditions must be met: a water source, a water volume, and a water-conducting channel. High-density induced polarization (IPP) can effectively monitor changes in water volume within the water-conducting fracture zone. When the water volume within the fracture zone changes, the apparent resistivity measured by the high-density IPP through the electrode string will decrease, while the apparent polarizability will increase.

[0045] Excited polarization method utilizes the differences in conductivity and excited polarization characteristics of different minerals and rocks to observe and study the variation law of excited-state polarization field. High-density excited polarization method is an upgrade and extension based on traditional high-density electrical resistivity method. It adds an independent polarizability data receiving channel and polarizability measuring instrument to the traditional high-density electrical resistivity instrument. It can obtain the apparent polarizability parameter by measuring the secondary field decay voltage between two non-polarized smart electrodes after the primary field is de-energized, while obtaining the apparent resistivity parameter of the borehole surrounding rock.

[0046] The high-density induced polarization method in this application embodiment can effectively monitor old working water, aquifer water content, faults caused by geological structures, and changes in water-conducting channels around the mining face or roadway. Since the apparent resistivity of water is relatively small, when there is water in the monitored geological structure, the apparent resistivity value monitored by the high-density induced polarization method will decrease, while the apparent polarizability value will increase.

[0047] The mine roof water hazard monitoring method based on induced polarization provided in this application offers two drilling methods depending on the development location of the water-conducting fracture zone on the mine roof: when the water-conducting fracture zone has developed to the surface, vertical drilling is performed on the side of the mine roof closer to the surface; when the water-conducting fracture zone has not developed to the surface, drilling is performed at a certain angle on the side of the mine roof closer to the working face. This makes it easier for the electrode string to enter the water-conducting fracture zone, thereby enabling the electrode string to obtain accurate monitoring data, reducing drilling difficulty and saving drilling costs.

[0048] The embodiments of this application involve deploying monitoring electrode strings in boreholes on the mine surface or in the mine roof, and using a high-density excitation polarization method to monitor changes in the apparent resistivity and apparent polarizability of the surrounding rock of the mine roof. When the surrounding rock of the coal seam develops cracks due to mining and water seeps out or flows out of the roof, a water inrush will occur. Correspondingly, the apparent resistivity of the surrounding rock decreases while the apparent polarizability increases. By monitoring the changes in the apparent resistivity and apparent polarizability of the surrounding rock throughout the borehole, this invention can accurately and timely monitor whether a water inrush has occurred in the mine roof, providing a good foundation for mine production and operation.

[0049] In some embodiments, such as Figure 1 As shown, the mine roof water hazard monitoring method based on induced polarization includes:

[0050] Step 100: Obtain the development location of the water-conducting fracture zone within the mine roof.

[0051] In this step, based on the geological and hydrogeological data of the mine to be monitored, it is necessary to select whether to drill holes on the surface or underground to determine the specific location, method, and spacing parameters of the monitoring electrode strings. The boreholes are used to install the electrode strings for monitoring water inrush. The arrangement of the electrode strings will be determined based on preliminary judgments of water-rich sections of the aquifer and weak zones of the aquitard, combined with locations prone to damage or water inrush and specific mining conditions. Generally, the main locations for electrode strings should be near the opening cut, near the final mining line, in areas subject to periodic pressure, at the corners of the coal face or roadway, in water-rich mining sections, and in weak zones of the aquitard. In this embodiment, the borehole location is determined based on the development location of the water-conducting fracture zone. The development height of the water-conducting fracture zone can be determined by methods such as borehole measurement or calculation using empirical formulas. Comparing the development height of the water-conducting fracture zone with the coal seam depth determines the development location of the water-conducting fracture zone. Figure 2 As shown, if the height of the water-conducting fracture zone is greater than or equal to the coal seam depth, it can be determined that the water-conducting fracture zone has developed to the surface; if... Figure 3 As shown, if the height of the water-conducting fracture zone is less than the coal seam burial depth, it is determined that the water-conducting fracture zone has not developed to the surface.

[0052] Step 200: In response to the development of a water-conducting fracture zone to the surface, determine the first borehole data on the side of the mine roof near the surface.

[0053] In this step, such as Figure 2 As shown, the mine roof, from the surface to the working face, consists of a loose layer, an aquifer, a weathered bedrock layer, another aquifer, and another bedrock layer. Above the mine roof is the surface, and below is the working face. When the water-conducting fracture zone develops to the surface, it is very close to the surface. Drilling a hole on one side of the surface allows for relatively easy placement of the electrode string within the water-conducting fracture zone. Therefore, as... Figure 4 As shown, the first borehole data was determined on the side of the mine roof near the ground, including:

[0054] Step 210: Determine the location of the collapse zone in the mine roof.

[0055] In this step, to avoid damage to the borehole and the electrode string installed in the borehole, the location of the collapse zone must first be determined to avoid drilling into the collapse zone.

[0056] Step 220: Determine the drilling depth of the ground monitoring borehole based on the preset safety distance.

[0057] In this step, the angle and depth of the borehole need to be designed according to the development of the water-conducting fracture zone in the mine roof. When the water-conducting fracture zone develops to the ground, the collapse zone should be avoided. The borehole can be drilled at an angle perpendicular to the ground. The design depth of the borehole on the ground side should be 10-20 meters away from the collapse zone.

[0058] Step 230: Determine the borehole spacing between adjacent ground monitoring boreholes based on the preset deployment ratio and the monitoring radius of the electrode string.

[0059] The deployment ratio is the ratio of the borehole depth to the total borehole depth.

[0060] In this step, when drilling, the spacing between boreholes can take into account the superposition of the influence radii of adjacent boreholes. The influence radius is the monitoring radius of the electrode string deployed in the borehole. This radius can be used as the final borehole spacing. However, the ratio of borehole depth to borehole spacing should be greater than 1.5 to obtain high-quality cross-hole high-density measurement results. Therefore, it is necessary to weigh the deployment ratio and the monitoring radius of the electrode string to determine the spacing between adjacent ground monitoring boreholes.

[0061] Step 300: Based on the first borehole data, open multiple ground monitoring boreholes in the direction perpendicular to the ground plane within the mine roof.

[0062] In this step, when drilling from one side of the ground is chosen, since drilling from one side only requires considering the drilling depth to avoid the collapse zone, multiple approximately straight ground monitoring boreholes can be opened in the direction perpendicular to the ground plane within the mine roof based on the first borehole data. For example, such as... Figure 5 As shown, two rows of approximately straight ground monitoring boreholes are drilled vertically to the ground, and electrode strings are arranged in multiple approximately straight ground monitoring boreholes. This array of ground monitoring boreholes can increase the monitoring range of the water-conducting fracture zone and enable more comprehensive real-time monitoring of the water-conducting fracture zone.

[0063] Optionally, when the electrode string is deployed in the ground monitoring borehole, steel wire ropes are used to protect the adjacent smart electrodes of the electrode string. At the same time, flexible materials such as hemp rope can be added when the electrode string is buried in the ground monitoring borehole to improve the integrity and stability of the borehole wall and reduce the risk of breakage or damage to the electrode string due to overburden damage. After the electrode string is deployed, the borehole can be sealed with anchoring agent, expansive cement or grouting.

[0064] Step 200', in response to the fact that the water-conducting fracture zone has not developed to the surface, determine the second borehole data on the side of the mine roof near the working face;

[0065] In this step, such as Figure 3 As shown, the mine roof, from the surface to the working face, consists of a loose layer, an aquifer, a weathered bedrock layer, another aquifer, and another bedrock layer. Above the mine roof is the surface, and below is the working face. When the water-conducting fracture zone has not developed to the surface, it is far from the surface. Drilling on the surface side would waste a long section of the borehole, which would generate significant interference signals. Furthermore, drilling could potentially introduce water from the aquifer into the water-conducting fracture zone, increasing the risk of water inrush. Therefore, determining the second borehole data on the side of the mine roof closer to the working face reduces subsequent drilling difficulty, costs, and interference signals, while also preventing an increase in the risk of water inrush due to drilling. Determining the second borehole data on the side of the mine roof closer to the working face, as shown... Figure 6 As shown, it includes:

[0066] Step 210': Determine the location of the collapse zone in the mine roof.

[0067] In this step, to avoid damage to the borehole and the electrode string installed in the borehole, the location of the collapse zone must first be determined to avoid drilling into the collapse zone.

[0068] Step 220': Determine the inclination angle of the downhole monitoring borehole based on the cross-fall angle between the water-conducting fracture zone and the collapse zone.

[0069] In this step, the angle and depth of the borehole need to be designed based on factors such as the development of water-conducting fracture zones in the mine roof. When the water-conducting fracture zones have not yet developed to the surface, the collapse zone must be avoided. Figure 3 As shown, the starting point for drilling needs to be located in the roadway underground. Depending on the different crossing angles of the water-conducting fracture zone and the collapse zone, the design can avoid the inclination angle of the collapse zone.

[0070] Step 230': Determine the borehole spacing and borehole depth of adjacent downhole monitoring boreholes based on the monitoring radius of the electrode string.

[0071] In this step, when drilling downhole, the spacing between boreholes also needs to take into account the superposition of the influence radii of adjacent boreholes. The influence radius is the monitoring radius of the electrode string deployed in the borehole. This radius can be used as the final borehole spacing. However, the ratio of borehole depth to borehole spacing should be greater than 1.5 to obtain high-quality cross-hole high-density measurement results. Therefore, it is necessary to weigh the deployment ratio and the monitoring radius of the electrode string to determine the spacing between adjacent surface monitoring boreholes.

[0072] Step 300': Based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to the preset inclination angle.

[0073] The angle between each underground monitoring borehole and the plane containing the lower surface of the mine roof is the inclination angle.

[0074] In this step, such as Figure 3 As shown, when drilling from underground, since it is necessary to consider how to avoid the collapse zone during drilling, multiple approximately straight underground monitoring boreholes can be opened at a preset inclination angle on one side of the working face of the mine roof based on the second borehole data. Therefore, for example, the underground monitoring boreholes are upward-facing boreholes, and their arrangement is as follows: Figure 7 The top view shown and as Figure 3 The boreholes shown in the frontal view are all fan-shaped. Two sets of approximately straight, fan-shaped downhole monitoring boreholes are drilled upwards at a certain angle. Electrode strings are arranged in these approximately straight downhole monitoring boreholes. This fan-shaped arrangement of downhole monitoring boreholes can increase the monitoring range of the water-conducting fracture zone, enabling more comprehensive real-time monitoring of the water-conducting fracture zone. A top-view schematic diagram of the downhole monitoring borehole layout is shown below. Figure 5 As shown, the frontal cross-sectional schematic diagram is as follows: Figure 3 As shown.

[0075] Optionally, when the electrode string is deployed in the downhole monitoring borehole, adjacent smart electrodes in the electrode string are protected by steel wire ropes. Simultaneously, flexible materials such as hemp rope can be added during the installation of the electrode string in the downhole monitoring borehole to improve the integrity and stability of the borehole wall, reducing the risk of breakage or damage to the electrode string due to overburden failure. After the electrode string is deployed, it can be sealed with anchoring agent, expansive cement, or grouting. Each electrode string uses a high-strength, shear-resistant, fixed-point distributed optical cable for connection between smart electrodes, improving the connection strength and preventing easy breakage. Even if breakage occurs, some smart electrodes can still transmit data.

[0076] Step 400: Determine whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode strings deployed in the ground monitoring boreholes or underground monitoring boreholes.

[0077] In this step, the apparent resistivity and apparent polarizability, obtained in real time by electrode strings deployed in ground monitoring boreholes, are used to determine whether there is water inrush around the mine roof. Figure 8 As shown, it includes:

[0078] Step 410: Determine the first current apparent resistivity and the first current apparent polarization obtained by the electrode string in the same ground monitoring borehole at the current moment, and the first historical apparent resistivity and the first historical apparent polarization obtained by the electrode string at the previous moment.

[0079] In this step, for the same surface monitoring borehole, the induced polarization method needs to calculate the difference between the measured value and the background value, and then compare this difference with a preset threshold to determine whether a water inrush has occurred within the monitoring range of the surface monitoring borehole. The measured values ​​can be the first current apparent resistivity and the first current apparent polarization acquired by the electrode string within the surface monitoring borehole at the current moment. The background value can be preset or a previous monitoring value. Generally, for the first set of apparent resistivity and apparent polarization data acquired by the electrode string, since there is no previous monitoring data, a preset background value is selected. For other data besides the first set, since the preset background value cannot accurately reflect the true situation of the water-conducting fracture zone, and water inrush rarely occurs in the first set of data, the first historical apparent resistivity and the first historical apparent polarization acquired by the electrode string at the previous moment are used as the background value for monitoring. The time interval between the current moment and the previous moment is set according to different mines and is not subject to many restrictions here.

[0080] Step 420: In response to the fact that the difference between the first historical apparent resistivity and the first current apparent resistivity is less than a preset first threshold, and the difference between the first historical apparent polarizability and the first current apparent polarizability is less than a preset second threshold, it is determined that there is no water inrush in the mine roof.

[0081] In this step, for example, a preset first threshold is set to twice the standard deviation of apparent resistivity, and a preset second threshold is set to twice the standard deviation of apparent polarizability. If the first current apparent resistivity of the mine roof surrounding rock measured by the electrode string is 280 Ω / m, and the first historical apparent resistivity (background value) of the mine roof surrounding rock is 310 Ω / m with a standard deviation of 20 Ω / m, then the decrease in apparent resistivity of the mine roof surrounding rock is 30 Ω / m, which is less than twice the standard deviation (preset first threshold) of 40 Ω / m. Simultaneously, if the first current apparent polarizability of the mine roof surrounding rock measured by the electrode string is 15%, and the first historical apparent polarizability of the mine roof surrounding rock is 10% with a standard deviation of 3%, then the increase in apparent polarizability of the mine roof surrounding rock is 5%, which is less than twice the standard deviation (preset second threshold) of 6%. Therefore, it is determined that there is no threat of water inrush to the mine roof.

[0082] Step 430: In response to the fact that the difference between the first historical apparent resistivity and the first current apparent resistivity is greater than a preset first threshold, and the difference between the first historical apparent polarizability and the first current apparent polarizability is greater than a preset second threshold, it is determined that there is a water inrush in the mine roof.

[0083] In this step, for example, a preset first threshold is set to twice the standard deviation of apparent resistivity, and a preset second threshold is set to twice the standard deviation of apparent polarizability. If the first current apparent resistivity of the mine roof surrounding rock measured by the electrode string is 260 Ω / m, and the first historical apparent resistivity (background value) of the mine roof surrounding rock is 310 Ω / m with a standard deviation of 20 Ω / m, then the decrease in apparent resistivity of the mine roof surrounding rock is 50 Ω / m, which is greater than twice the standard deviation (preset first threshold) of 40 Ω / m. Simultaneously, if the first current apparent polarizability of the mine roof surrounding rock measured by the electrode string is 17%, and the first historical apparent polarizability of the mine roof surrounding rock is 10% with a standard deviation of 3%, then the increase in apparent polarizability of the mine roof surrounding rock is 7%, which is greater than twice the standard deviation (preset second threshold) of 6%. Therefore, it is determined that there is a threat of water inrush at this time. Through the above determination, water inrush monitoring and prediction of the mine roof surrounding rock can be achieved.

[0084] In some embodiments, such as Figure 9 As shown, the determination of whether there is water inrush around the mine roof is based on the apparent resistivity and apparent polarizability obtained in real time by the electrode string deployed in the underground monitoring borehole, including:

[0085] Step 410': Determine the second current apparent resistivity and second current apparent polarization obtained by the electrode string in the same downhole monitoring borehole at the current moment, and the second historical apparent resistivity and second historical apparent polarization obtained by the electrode string at the previous moment.

[0086] In this step, for the same downhole monitoring borehole, the induced polarization method needs to calculate the difference between the measured value and the background value, and then compare this difference with a preset threshold to determine whether a water inrush has occurred within the monitoring range of the surface monitoring borehole. The measured value can be the second current apparent resistivity and the second current apparent polarization acquired by the electrode string in the downhole monitoring borehole at the current moment. The background value can be preset or it can be the previous monitoring value during the monitoring process. Generally, for the first set of apparent resistivity and apparent polarization data acquired by the electrode string, since there is no previous monitoring data, the preset background value is selected. For other data besides the first set of data, since the preset background value cannot accurately reflect the real situation of the water-conducting fracture zone, and it is rare for a water inrush to occur in the first set of data, the second historical apparent resistivity and the second historical apparent polarization acquired by the electrode string at the previous moment are used as the background value for monitoring.

[0087] Step 420': In response to the fact that the difference between the second historical apparent resistivity and the second current apparent resistivity is less than a preset third threshold, and the difference between the second historical apparent polarizability and the second current apparent polarizability is less than a preset fourth threshold, it is determined that there is no water inrush in the mine roof.

[0088] In this step, for example, let the preset third threshold be twice the standard deviation of apparent resistivity, and the preset fourth threshold be twice the standard deviation of apparent polarizability. If the second current apparent resistivity of the mine roof surrounding rock measured by the electrode string is 300 Ω / m, and the second historical apparent resistivity (background value) of the mine roof surrounding rock is 340 Ω / m with a standard deviation of 25 Ω / m, then the apparent resistivity of the mine roof surrounding rock decreases to 40 Ω / m, which is less than twice the standard deviation (preset third threshold) of 50 Ω / m. Simultaneously, if the second current apparent polarizability of the mine roof surrounding rock measured by the electrode string is 10%, and the second historical apparent polarizability of the mine roof surrounding rock is 8% with a standard deviation of 2%, then the apparent polarizability of the mine roof surrounding rock increases to 2%, which is less than twice the standard deviation (preset fourth threshold) of 4%. Therefore, it is determined that there is no threat of water inrush to the mine roof.

[0089] Step 430': In response to the difference between the second historical apparent resistivity and the second current apparent resistivity being greater than a preset third threshold, and the difference between the second historical apparent polarizability and the second current apparent polarizability being greater than a preset fourth threshold, it is determined that there is a water inrush in the mine roof.

[0090] In this step, for example, let the preset third threshold be twice the standard deviation of apparent resistivity and the preset fourth threshold be twice the standard deviation of apparent polarizability. In this case, if the second current apparent resistivity of the mine roof surrounding rock measured by the electrode string is 300 Ω / m and the second historical apparent resistivity (background value) of the mine roof surrounding rock is 400 Ω / m with a standard deviation of 25 Ω / m, then the decrease in apparent resistivity of the mine roof surrounding rock is 100 Ω / m, which is greater than twice the standard deviation (preset third threshold) 50 Ω / m. At the same time, if the second current apparent polarizability of the mine roof surrounding rock measured by the electrode string is 15% and the second historical apparent polarizability of the mine roof surrounding rock is 8% with a standard deviation of 2%, then the increase in apparent polarizability of the mine roof surrounding rock is 7%, which is greater than twice the standard deviation (preset fourth threshold) 4%. Therefore, by determining that there is a threat of water inrush in the mine roof, the above-mentioned judgment can be used to achieve water inrush monitoring and prediction of the surrounding rock of the mine roof.

[0091] In some embodiments, such as Figure 10 As shown, the mine roof water hazard monitoring method based on induced polarization also includes determining the development location of water-conducting fracture zones through the following methods:

[0092] Step 110: Obtain the coal seam burial depth and the development height of the water-conducting fracture zone in the mine roof.

[0093] Step 120: In response to the fact that the development height of the water-conducting fracture zone is greater than or equal to the coal seam burial depth, determine that the water-conducting fracture zone has developed to the surface.

[0094] Step 130: In response to the fact that the height of the water-conducting fracture zone is less than the coal seam burial depth, it is determined that the water-conducting fracture zone has not developed to the surface.

[0095] To determine the development of water-conducting fracture zones, it is first necessary to obtain the coal seam burial depth and the development height of the water-conducting fracture zone in the mine roof. By comparing the two, the location of the water-conducting fracture zone can be determined. If the development height of the water-conducting fracture zone is greater than or equal to the coal seam burial depth, it can be determined that the water-conducting fracture zone has developed to the surface, and surface drilling is required. If the development height of the water-conducting fracture zone is less than the coal seam burial depth, it can be determined that the water-conducting fracture zone has not yet developed to the surface, and underground drilling is required.

[0096] It should be noted that the method in this embodiment can be executed by a single device, such as a computer or server. The method can also be applied in a distributed scenario, where multiple devices cooperate to complete the task. In such a distributed scenario, one of these devices may execute only one or more steps of the method in this embodiment, and the multiple devices will interact with each other to complete the method described.

[0097] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0098] Based on the same inventive concept, and corresponding to any of the above embodiments, this application also provides a mine roof water hazard monitoring device based on induced polarization method.

[0099] refer to Figure 11 The mine roof water hazard monitoring device based on induced polarization method includes:

[0100] Data acquisition module 10 is configured to: acquire the development location of the water-conducting fracture zone at the location of the mine roof;

[0101] Drilling module 20 is configured to: in response to the development of a water-conducting fracture zone to the surface, determine first borehole data on the side of the mine roof near the surface; and based on the first borehole data, drill multiple surface monitoring boreholes in the mine roof in a direction perpendicular to the plane of the surface; or,

[0102] In response to the fact that the water-conducting fracture zone has not developed to the surface, second borehole data is determined on the side of the mine roof near the working face; based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between each underground monitoring borehole and the plane on which the lower surface of the mine roof is located is the inclination angle.

[0103] The monitoring module 30 is configured to determine whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode strings deployed in the ground monitoring borehole or underground monitoring borehole.

[0104] For ease of description, the above devices are described in terms of function, divided into various modules. Of course, in implementing this application, the functions of each module can be implemented in one or more software and / or hardware.

[0105] The apparatus of the above embodiments is used to implement the corresponding mine roof water hazard monitoring method based on induced polarization method in any of the foregoing embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0106] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the mine roof water hazard monitoring method based on induced polarization method described in any of the above embodiments.

[0107] Figure 12 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0108] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0109] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0110] The input / output interface 1030 is used to connect input / output modules to realize information input and output. Input / output modules can be configured as components within the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touchscreens, microphones, various sensors, etc., while output devices may include displays, speakers, vibrators, indicator lights, etc.

[0111] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0112] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0113] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0114] The electronic devices described above are used to implement the corresponding mine roof water hazard monitoring method based on induced polarization method in any of the foregoing embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0115] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to execute the mine roof water hazard monitoring method based on induced polarization method as described in any of the above embodiments.

[0116] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0117] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to execute the mine roof water hazard monitoring method based on the induced polarization method as described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0118] Based on the same inventive concept, and corresponding to any of the above embodiments, this application also provides a mine roof water hazard monitoring system based on induced polarization method.

[0119] refer to Figure 13 and Figure 14 The mine roof water hazard monitoring system based on induced polarization includes a general monitoring substation, a control unit, an electrode string, and electronic equipment as described in the above embodiments.

[0120] The electronic device is configured to: acquire the development location of a water-conducting fracture zone at a location on the mine roof; in response to the water-conducting fracture zone developing to the surface, determine first borehole data on the side of the mine roof near the surface; based on the first borehole data, open multiple surface monitoring boreholes in the mine roof in a direction perpendicular to the plane where the surface is located; or, in response to the water-conducting fracture zone not developing to the surface, determine second borehole data on the side of the mine roof near the working face; based on the second borehole data, open multiple underground monitoring boreholes on the side of the mine roof near the working face according to a preset inclination angle; wherein the angle between the underground monitoring boreholes and the plane where the lower surface of the mine roof is located is the inclination angle.

[0121] Electrode strings are deployed in surface monitoring boreholes or downhole monitoring boreholes. Each electrode string is connected to the smart electrodes using a fixed-point distributed optical cable. The electrode strings are configured to acquire the apparent resistivity and apparent polarization around the surface monitoring boreholes or downhole monitoring boreholes in real time.

[0122] The sub-controller is connected to the electrode string and is configured to control the electrode string to perform high-density excitation polarization measurements around the surface monitoring borehole or underground monitoring borehole in the mine roof.

[0123] The monitoring general substation is connected to the sub-control unit and is configured to: send control signals to the sub-control unit and collect apparent resistivity and apparent polarization sent by multiple electrode strings;

[0124] The electronic equipment is connected to the general monitoring substation and is also configured to determine whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time from the electrode string.

[0125] Optionally, the electronic device may be Figure 13 and Figure 14 The monitoring host shown.

[0126] Among them, such as Figure 13 and Figure 14As shown, the mine roof water hazard monitoring system based on induced polarization mainly includes a monitoring electrode string, a sub-control unit, a general monitoring substation, and a monitoring host. It also includes an Ethernet ring network switch, fiber optic line terminal, PC client, and Web server connected to the above components. This system provides two technical solutions based on the actual conditions of the mine. The two solutions are essentially the same, differing only in the drilling and system deployment. Optionally, when the water-conducting fracture zone extends to the surface, the drilling and monitoring system are deployed on the surface side, as illustrated in the schematic diagram. Figure 12 As shown; optionally, when the water-conducting fracture zone has not developed to the surface, a borehole and monitoring system can be installed on one side of the well, and its layout structure is shown in the schematic diagram. Figure 13 As shown.

[0127] For example, such as Figure 13 and Figure 14 As shown, two sets of 16 electrode strings are deployed in surface detection boreholes or underground monitoring boreholes. The control unit is connected to the electrode strings via a communication transmission cable. The general monitoring substation is connected to the control unit via a comprehensive communication cable. Each Ethernet switch is connected via optical fiber to form an industrial Ethernet ring network. The general monitoring substation is connected to the nearest Ethernet ring network switch via optical fiber, and then connected to the monitoring host via an optical fiber line terminal. The monitoring host receives the data transmitted by the general monitoring substation, processes the data, shares it with each PC client, and stores the data on a Web server, forming a mine roof water hazard monitoring system using the induced polarization method. This system is deployed either on the surface or underground depending on the actual conditions of the mine.

[0128] For example, such as Figure 15 As shown, the electrode string consists of five smart electrodes connected in series, with equal spacing between them. The distance between two adjacent smart electrodes is the unit electrode spacing, which can be 8 meters. The electrode string is used to monitor the electric field signal of the surrounding rock in the mine roof. In other embodiments, the electrodes can be customized according to the characteristics of different mines, and the positional relationship between the power supply electrodes (AB) and the receiving electrodes (MN) can be arranged to form a targeted arrangement. This is especially effective in complex mines with many obstacles, achieving flexible electrode placement. Each electrode string uses a high-strength, shear-resistant, fixed-point distributed optical cable to connect the smart electrodes, improving the connection strength and preventing easy breakage. Even if a break occurs, the smart electrode before the break point can still transmit data, avoiding monitoring interruption due to local damage to the electrode string.

[0129] like Figure 16 As shown, the intelligent electrode consists of an electrode and an electrode connection box. The electrode and the electrode connection box are each welded to a metal sheet and connected by a snap-fit. The electrode connection box is equipped with a control circuit, a drive circuit, and an electrode switching switch. The electrode connection box performs electrode switching and data acquisition and transmission according to the commands of the monitoring general substation.

[0130] Specifically, the smart electrode combines the electrode with an electrode switching switch, distributing the switching switches across each electrode to achieve distributed high-density electrical resistivity tomography (EDT). This allows each smart electrode to potentially function as either an AB pole or an MN pole, switching between the power supply electrode (AB) and the receiving electrode (MN). Furthermore, each electrode is equipped with GPS for positioning, enabling location and repair in case of electrode string damage.

[0131] The sub-controller adopts a PLC sub-controller, which has a simple structure, high stability, strong anti-interference, wide adaptability, and low cost. It is used to receive signals sent by the general monitoring substation and control the monitoring electrode string to perform high-density excitation polarization measurement on the surrounding rock of the mine roof.

[0132] Among them, such as Figure 17 As shown, the general monitoring substation includes a central control module, and a signal transmitter, a signal receiving amplifier processor, a data storage device, a power module, a human-machine interface component, and a fiber optic interface, all connected to the central control module. The general monitoring substation is used to transmit control signals to the sub-control unit and to collect the apparent resistivity and apparent polarization sent by multiple electrode strings.

[0133] Optionally, the signal transmitter is connected to the sub-controller to transmit control signals to it. The signal receiving and amplifying processor includes a receiving module, an amplifying module, a filtering module, and an A / D conversion module. The receiving module is connected to the sub-controller to receive the apparent resistivity and apparent polarizability transmitted by each electrode string. The amplifying module is connected to the receiving module to amplify the apparent resistivity and apparent polarizability output by the receiving module. The filtering module is connected to the amplifying module to filter out specific frequency points or frequencies other than those frequencies to obtain the apparent resistivity and apparent polarizability at a specific frequency, or to eliminate the apparent resistivity and apparent polarizability after a specific frequency is reached. The A / D conversion module is connected to the filtering module to digitize the electric field signals (apparent resistivity and apparent polarizability) filtered out by the filtering module. The data storage device is used to store the real-time data collected by the electrode strings. The human-machine interface components include an LCD screen, a touch screen, and a touch keyboard, which can display the current working status and monitoring data of each electrode string. The power module includes a high-voltage DC power supply, IGBTs, and a drive circuit. IGBTs are composite, fully controllable, voltage-driven power semiconductor devices used in converter systems with DC voltages of 600V and above. Using this type of transistor effectively improves power efficiency, reduces heat loss, and lowers noise. The high-voltage DC power supply is a 0-1000V intelligent constant current or constant voltage power supply, selected in constant current 10A mode. When the primary voltage is low, the current is appropriately increased to power the various modules in the general monitoring substation. The drive circuit drives the IGBTs, amplifying the pulses output by the microcontroller to ensure reliable IGBT operation. An optical fiber interface connects the general monitoring substation to the Ethernet ring network switch via an access fiber optic cable, transmitting monitoring data within the industrial Ethernet ring network.

[0134] Among them, Ethernet ring network switches are switches that transmit data based on Ethernet. Ethernet ring network switches form an industrial Ethernet ring network through the connection of optical cables.

[0135] Among them, the fiber optic line terminal is the terminal equipment for optical signal transmission, used to detect the signal conversion between the general substation and the monitoring host. It includes an optical transmitter and an optical receiver. The optical transmitter mainly transmits optical signals for optical cable transmission and completes the electro-optical conversion; the optical receiver completes the photoelectric conversion and restores the optical signal received from the optical cable to an electrical signal.

[0136] The monitoring host (electronic device) is equipped with remote control software and real-time data processing software. It is used to control the general monitoring substation to issue commands for monitoring, and to collect, process and image data of the apparent resistivity and apparent polarizability of the mine roof surrounding rock in real time. Based on the changes in the data, it determines whether there is water inrush in the mine roof surrounding rock, and conducts monitoring and early warning. Finally, the results are transmitted to the PC client through the industrial Ethernet ring network to remind the staff to take disaster prevention measures. The data is also stored on the Web server to facilitate the staff to analyze the cause of water inrush.

[0137] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0138] Additionally, to simplify the description and discussion, and to avoid obscuring the embodiments of this application, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be shown in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details (e.g., circuits) have been set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application can be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0139] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0140] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for monitoring water hazards in mine roofs based on induced polarization, characterized in that, include: The location of the water-conducting fracture zone within the mine roof is determined; In response to the development of the water-conducting fracture zone to the surface, first borehole data is determined on the side of the mine roof near the surface; based on the first borehole data, multiple surface monitoring boreholes are opened in the mine roof in a direction perpendicular to the plane where the surface is located. In response to the fact that the water-conducting fracture zone has not developed to the surface, second borehole data is determined on the side of the mine roof near the working face; based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to a preset inclination angle; The presence of water inrush around the mine roof is determined by real-time acquisition of apparent resistivity and apparent polarization from electrode strings deployed in the ground monitoring boreholes or the underground monitoring boreholes. The step of determining the first borehole data on the side of the mine roof near the ground includes: The location of the collapse zone is determined in the mine roof to prevent the surface monitoring borehole from being drilled into the collapse zone; The drilling depth of the ground monitoring borehole is determined based on a preset safety distance; The spacing between adjacent ground monitoring boreholes is determined based on a preset deployment ratio and the monitoring radius of the electrode string; the deployment ratio is the ratio of the borehole depth to the borehole spacing. The step of determining the second borehole data on the side of the mine roof near the working face includes: The location of the collapse zone is determined in the mine roof to prevent the underground monitoring borehole from being drilled into the collapse zone; The inclination angle of the downhole monitoring borehole is determined based on the collapse angle between the water-conducting fracture zone and the collapse zone. The borehole spacing and depth of adjacent downhole monitoring boreholes are determined based on the monitoring radius of the electrode string.

2. The method according to claim 1, characterized in that, The method further includes determining the development location of the water-conducting fracture zone by the following method: The coal seam burial depth of the mine roof and the development height of the water-conducting fracture zone are obtained; In response to the fact that the development height of the water-conducting fracture zone is greater than or equal to the coal seam burial depth, it is determined that the water-conducting fracture zone has developed to the surface; In response to the fact that the development height of the water-conducting fracture zone is less than the coal seam burial depth, it is determined that the water-conducting fracture zone has not developed to the surface.

3. The method according to claim 1, characterized in that, The method of determining whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode string deployed in the ground monitoring borehole includes: Determine the first current apparent resistivity and the first current apparent polarization at the current moment obtained by the electrode string within the same ground monitoring borehole, and the first historical apparent resistivity and the first historical apparent polarization obtained by the electrode string at the previous moment; In response to the fact that the difference between the first historical apparent resistivity and the first current apparent resistivity is less than a preset first threshold, and the difference between the first historical apparent polarizability and the first current apparent polarizability is less than a preset second threshold, it is determined that there is no water inrush in the mine roof; or, In response to the fact that the difference between the first historical apparent resistivity and the first current apparent resistivity is greater than a preset first threshold, and the difference between the first historical apparent polarizability and the first current apparent polarizability is greater than a preset second threshold, it is determined that there is a water inrush in the mine roof.

4. The method according to claim 1, characterized in that, The method of determining whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode string deployed in the underground monitoring borehole includes: Determine the second current apparent resistivity and second current apparent polarization at the current moment obtained by the electrode string in the same downhole monitoring borehole, and the second historical apparent resistivity and second historical apparent polarization obtained by the electrode string at the previous moment; In response to the fact that the difference between the second historical apparent resistivity and the second current apparent resistivity is less than a preset third threshold, and the difference between the second historical apparent polarizability and the second current apparent polarizability is less than a preset fourth threshold, it is determined that there is no water inrush in the mine roof; or, In response to the fact that the difference between the second historical apparent resistivity and the second current apparent resistivity is greater than a preset third threshold, and the difference between the second historical apparent polarizability and the second current apparent polarizability is greater than a preset fourth threshold, it is determined that there is a water inrush in the mine roof.

5. A mine roof water hazard monitoring device based on induced polarization method, characterized in that, include: Data acquisition module: Acquires the development location of the water-conducting fracture zone at the location of the mine roof; The drilling module is configured to: in response to the development of the water-conducting fracture zone to the ground, determine first drilling data on the side of the mine roof near the ground; and based on the first drilling data, drill multiple ground monitoring boreholes in the mine roof in a direction perpendicular to the plane where the ground is located. In response to the fact that the water-conducting fracture zone has not developed to the surface, second borehole data is determined on the side of the mine roof near the working face; based on the second borehole data, multiple underground monitoring boreholes are opened on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between each underground monitoring borehole and the plane containing the lower surface of the mine roof is the inclination angle. The monitoring module is configured to determine whether there is a water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode strings deployed in the ground monitoring borehole or the underground monitoring borehole. The step of determining the first borehole data on the side of the mine roof near the ground includes: The location of the collapse zone is determined in the mine roof to prevent the surface monitoring borehole from being drilled into the collapse zone; The drilling depth of the ground monitoring borehole is determined based on a preset safety distance; The borehole spacing between adjacent ground monitoring boreholes is determined based on a preset deployment ratio and the monitoring radius of the electrode string; the deployment ratio is the ratio of the borehole depth to the borehole spacing. The step of determining the second borehole data on the side of the mine roof near the working face includes: The location of the collapse zone is determined in the mine roof to prevent the underground monitoring borehole from being drilled into the collapse zone; The inclination angle of the downhole monitoring borehole is determined based on the collapse angle between the water-conducting fracture zone and the collapse zone. The borehole spacing and depth of adjacent downhole monitoring boreholes are determined based on the monitoring radius of the electrode string.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method as claimed in any one of claims 1 to 4.

7. A non-transitory computer-readable storage medium storing computer instructions for causing a computer to perform the method of any one of claims 1 to 4.

8. A mine roof water hazard monitoring system based on induced polarization method, characterized in that, Includes a general monitoring substation, a sub-control unit, an electrode string, and the electronic equipment as described in claim 6: The electronic device is configured to: acquire the development location of a water-conducting fracture zone at the location of the mine roof; in response to the water-conducting fracture zone developing to the surface, determine first borehole data on the side of the mine roof near the surface; based on the first borehole data, open multiple surface monitoring boreholes in the mine roof in a direction perpendicular to the plane where the surface is located; in response to the water-conducting fracture zone not developing to the surface, determine second borehole data on the side of the mine roof near the working face; based on the second borehole data, open multiple underground monitoring boreholes on the side of the mine roof near the working face according to a preset inclination angle; wherein, the angle between the underground monitoring boreholes and the plane where the lower surface of the mine roof is located is the inclination angle. The electrode strings are deployed in the surface monitoring borehole or the downhole monitoring borehole, wherein each electrode string is connected to the smart electrodes by a fixed-point distributed optical cable, and the electrode strings are configured to: acquire the apparent resistivity and apparent polarization around the surface monitoring borehole or the downhole monitoring borehole in real time; The sub-controller is connected to the electrode string and is configured to: control the electrode string to perform high-density excitation polarization measurement on the surface monitoring borehole or the area around the underground monitoring borehole in the mine roof; The monitoring general substation is connected to the sub-control unit and is configured to: send control signals to the sub-control unit and collect the apparent resistivity and apparent polarization sent by multiple electrode strings; The electronic device is connected to the monitoring general substation and is also configured to: determine whether there is water inrush around the mine roof based on the apparent resistivity and apparent polarizability obtained in real time by the electrode string; The step of determining the first borehole data on the side of the mine roof near the ground includes: The location of the collapse zone is determined in the mine roof to prevent the surface monitoring borehole from being drilled into the collapse zone; The drilling depth of the ground monitoring borehole is determined based on a preset safety distance; The spacing between adjacent ground monitoring boreholes is determined based on a preset deployment ratio and the monitoring radius of the electrode string; the deployment ratio is the ratio of the borehole depth to the borehole spacing. The step of determining the second borehole data on the side of the mine roof near the working face includes: The location of the collapse zone is determined in the mine roof to prevent the underground monitoring borehole from being drilled into the collapse zone; The inclination angle of the downhole monitoring borehole is determined based on the collapse angle between the water-conducting fracture zone and the collapse zone. The borehole spacing and depth of adjacent downhole monitoring boreholes are determined based on the monitoring radius of the electrode string.

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