Method for testing advanced support stress of near-vertical seam

Abstract

The application discloses a testing method for advanced support stress of near-vertical seam, which comprises the following steps: constructing a numerical simulation model for mining of near-vertical seam based on geological parameters and mining parameters of the near-vertical seam, simulating a coal seam mining process, and determining an advanced support stress concentration area in front of a working face; further determining spatial distribution parameters based on spatial distribution characteristics of the advanced support stress concentration area, and formulating a stress sensor installation scheme according to the spatial distribution parameters, drilling a monitoring hole in a roadway, and installing a stress sensor, so as to realize accurate monitoring of the advanced support stress of the near-vertical seam. The method can effectively solve the problem that a traditional fixed monitoring mode is difficult to adapt to the inclined and asymmetric distribution of the advanced support stress of the near-vertical seam, improve the accuracy of arrangement of the stress sensor and the reliability of monitoring data, and thus improve the accuracy and engineering applicability of the rock burst monitoring and early warning of the near-vertical seam.

Description

Technical Field

[0001] This application relates to the technical field of coal mine monitoring, and in particular to a test method for the pre-support stress of near-vertical coal seams. Background Technology

[0002] With the increasing depth and intensity of coal mining in my country, dynamic disasters such as rock bursts are becoming increasingly prominent, placing higher demands on the accurate monitoring of pre-support stress in the working face. Near-vertical coal seams typically refer to those with a dip angle of 85°–90°, and their occurrence state and stress evolution patterns differ significantly from those of horizontal and gently dipping coal seams. During the mining of near-vertical coal seams, influenced by gravity, bedding structure, and overburden movement, the stress concentration zone in front of the working face is often inclined and asymmetrically distributed, extending along the roof and floor of the roadway. Its spatial morphology and evolution patterns are more complex, making traditional stress distribution theories and monitoring experience based on horizontal coal seams difficult to apply directly.

[0003] Currently, underground monitoring of pre-support stress is primarily conducted using coal seam stress gauges and borehole stress sensors. However, existing setups typically involve setting up equipment at fixed intervals and depths along the roadway direction, assuming a symmetrical stress field distribution and stable principal stress directions. However, in near-vertical coal seams, the location of stress concentration zones and the direction of maximum principal stress exhibit significant shifts. If traditional fixed-parameter setups are still used, the monitoring equipment may deviate from the actual high-stress area, or the monitoring direction may mismatch with the principal stress, thus affecting the accuracy and reliability of the monitoring results. Summary of the Invention

[0004] The purpose of this application is to overcome the above-mentioned problems and provide a test method, storage medium, electronic device and computer program product for the advanced support stress of near-vertical coal seams.

[0005] The technical solution of this application provides a method for testing the pre-support stress in near-vertical coal seams, including: Based on the geological and mining parameters of the target near-vertical coal seam, a numerical simulation model for mining near-vertical coal seams is constructed. Based on the numerical simulation model of near-vertical coal seam mining, the coal seam mining process is simulated to determine the stress concentration zone of the advance support in front of the working face. Based on the spatial distribution characteristics of the stress concentration area of ​​the advanced support, the spatial distribution parameters of the stress concentration area of ​​the advanced support are determined; Based on the spatial distribution parameters, determine the stress sensor installation scheme; According to the stress sensor installation scheme, a monitoring borehole is constructed in the roadway, and a stress sensor is installed in the monitoring borehole.

[0006] Furthermore, after installing the stress sensor in the monitoring borehole, the method further includes: During coal seam mining, the stress sensor is monitored in real time, and its position is adjusted based on changes in the spatial distance between the stress sensor and the working face and / or changes in stress monitoring values.

[0007] Furthermore, adjusting the position of the stress sensor based on changes in the spatial distance between the stress sensor and the working surface and / or changes in stress monitoring values ​​specifically includes: The stress sensor located in front of the working surface and closest to the working surface is used as the sensor to be transferred. When the distance between the sensor to be transferred and the working surface is less than a preset distance threshold, and / or the stress monitoring value of the sensor to be transferred drops to the preset threshold range after reaching its peak value, the sensor to be transferred is disassembled and recycled. The disassembled sensor to be transferred is installed at the leading edge monitoring position of the stress concentration zone of the advanced support in front of the working face.

[0008] Furthermore, the numerical simulation model for near-vertical coal seam mining includes numerically simulated stress values ​​and original rock stress values; The numerical simulation model for near-vertical coal seam mining simulates the coal seam recovery process and determines the stress concentration zone of the advance support ahead of the working face, specifically including: Based on the numerical simulation stress value and the original rock stress value, the stress concentration factor at each location in the numerical simulation model is determined; If the stress concentration factor is greater than the preset critical threshold factor, the corresponding region will be determined as the advanced support stress concentration zone.

[0009] Furthermore, the spatial distribution characteristics include the spatial coordinate data of the boundary nodes of the advanced support stress concentration zone; The spatial distribution parameters include the directional distance between the stress concentration area of ​​the advanced support and the roadway, the vertical distance between the stress concentration area of ​​the advanced support and the roadway, and the range of the angle between the stress concentration area of ​​the advanced support and the horizontal direction. The determination of the spatial distribution parameters of the stress concentration zone of the advanced support based on its spatial distribution characteristics specifically includes: Obtain the spatial coordinate data of the boundary nodes of the stress concentration zone of the advanced support; Based on the spatial coordinate data of the boundary nodes, calculate the distance of the advanced support stress concentration zone relative to the roadway, the vertical distance relative to the roadway, and the range of the included angle relative to the horizontal direction. The vertical distance includes the maximum extension height of the top plate and the maximum extension depth of the bottom plate; The included angle range includes the maximum and minimum included angle values ​​of the line connecting the boundary node of the advanced support stress concentration zone and the preset reference point relative to the horizontal plane.

[0010] Furthermore, the spatial distribution parameters include the directional distance between the stress concentration area of ​​the advanced support and the roadway, the vertical distance between the stress concentration area of ​​the advanced support and the roadway, and the range of the angle between the stress concentration area of ​​the advanced support and the horizontal direction. The step of determining the stress sensor installation scheme based on the spatial distribution parameters specifically includes: The direction monitoring range is determined based on the stated direction distance; The burial depth of the monitoring borehole is determined based on the vertical distance. The construction angle of the monitoring borehole is determined based on the included angle range; The stress sensor installation scheme is determined based on the described direction monitoring range, the described burial depth, and the described construction angle.

[0011] Furthermore, the stress sensor installation scheme includes monitoring the drilling angle, burial depth, and orientation range of the borehole; The step of constructing monitoring boreholes in the roadway according to the stress sensor installation scheme, and installing stress sensors in the monitoring boreholes, specifically includes: Within the preset range of the pre-support stress concentration zone, the monitoring borehole is constructed according to the construction angle and the burial depth of the monitoring borehole; At least two stress sensors are installed in the monitoring borehole, located at the shallow base point and the deep base point, respectively. Adjust the stress sensor so that its installation depth is less than the distance between the roadway and the edge of the stress concentration area of ​​the advanced support, and the force direction of the stress sensor is perpendicular to the horizontal stress direction.

[0012] The technical solution of this application also provides a storage medium that stores computer instructions, which, when executed by a computer, are used to perform a test method for the pre-support stress of a near-vertical coal seam as described above.

[0013] The technical solution of this application also provides an electronic device, including at least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform a test method for the pre-support stress of a near-vertical coal seam as described above.

[0014] The technical solution of this application also provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements a method for testing the advanced support stress of a near-vertical coal seam as described above.

[0015] The above technical solution has the following beneficial effects: This application discloses a method for testing the pre-support stress in near-vertical coal seams. It constructs a numerical simulation model of near-vertical coal seam mining based on geological and mining parameters to simulate the coal seam recovery process and identify the pre-support stress concentration zone ahead of the working face. Furthermore, it determines spatial distribution parameters based on the spatial distribution characteristics of this stress concentration zone and formulates a stress sensor installation plan accordingly. Monitoring boreholes are drilled in the roadway, and stress sensors are installed to achieve accurate monitoring of the pre-support stress in near-vertical coal seams. This method effectively solves the problem that traditional fixed monitoring methods are ill-suited to the inclined and asymmetrical distribution of pre-support stress in near-vertical coal seams, improving the accuracy of stress sensor placement and the reliability of monitoring data, thereby enhancing the accuracy and engineering applicability of near-vertical coal seam rockburst monitoring and early warning. Attached Figure Description

[0016] The disclosure of this application will become more readily understood with reference to the accompanying drawings. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. In the drawings: Figure 1 This is a flowchart of a method for testing the advanced support stress of a near-vertical coal seam according to an embodiment of this application; Figure 2 This is a flowchart illustrating a method for testing the pre-support stress of a near-vertical coal seam, as described in one embodiment of this application. Figure 3 This is a parameter calculation diagram of the stress concentration zone of the near-vertical coal seam advanced support in one embodiment of this application; Figure 4 This is a schematic diagram of the hardware structure of an electronic device in one embodiment of this application. Detailed Implementation

[0017] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0018] It is readily understood that, based on the technical solution of this application, various structural and implementation methods can be interchanged by those skilled in the art without altering the essential spirit of this application. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this application and should not be considered as the entirety of this application or as limitations or restrictions on the technical solution of the application.

[0019] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meanings of the above in this application according to the specific circumstances.

[0021] like Figure 1 The flowchart shown is a process diagram of a method for testing the pre-support stress of a near-vertical coal seam according to an embodiment of this application, including: Step S101: Based on the geological parameters and mining parameters of the target near-vertical coal seam, construct a numerical simulation model for mining the near-vertical coal seam; Step S102: Based on the numerical simulation model of near-vertical coal seam mining, simulate the coal seam mining process and determine the stress concentration zone of the advance support in front of the working face; Step S103: Determine the spatial distribution parameters of the stress concentration zone of the advanced support based on the spatial distribution characteristics of the stress concentration zone of the advanced support; Step S104: Determine the stress sensor installation scheme based on the spatial distribution parameters; Step S105: Construct monitoring boreholes in the roadway according to the stress sensor installation scheme, and install stress sensors in the monitoring boreholes.

[0022] Specifically, in step S101, the geological parameters and mining parameters of the target near-vertical coal seam are first obtained, and a numerical simulation model for mining the near-vertical coal seam is constructed based on the geological parameters and mining parameters. Among them, FLAC3D numerical simulation software can be used to construct a refined mining model, which can be used to realistically reflect the bedding structure characteristics of near-vertical coal seams with dip angles greater than 85°, and the roof and floor strata are equivalent to weak surface structures controlled by bedding planes, so as to simulate the mechanical behavior of rock mass sliding and bending along bedding planes under near-vertical coal seam conditions, thereby improving the consistency between numerical simulation results and actual mining conditions.

[0023] In step S102, the coal seam mining process is simulated based on the near-vertical coal seam mining numerical simulation model to obtain the distribution of the pre-support stress ahead of the working face and to determine the pre-support stress concentration zone. Specifically, by simulating the dynamic change process of the surrounding rock stress at different mining stages, a pre-support stress distribution cloud map ahead of the working face is extracted to identify inclined and asymmetric stress concentration areas formed by gravity and bedding structure. Furthermore, the stress concentration coefficient can be determined based on the numerical simulation stress value and the original rock stress value, and the relationship between the stress concentration coefficient and a preset threshold can be used to determine whether the corresponding area belongs to the pre-support stress concentration zone, thereby improving the accuracy of stress concentration zone identification.

[0024] In step S103, the spatial distribution parameters of the stress concentration zone in the advanced support are determined based on its spatial distribution characteristics. Specifically, this can be achieved by acquiring the spatial coordinate data of the boundary nodes of the stress concentration zone and calculating the distance between the stress concentration zone and the roadway, the vertical distance, and the angle range relative to the horizontal direction. The vertical distance may include the maximum extension height of the roof and the maximum extension depth of the floor, and the angle range may include the maximum and minimum angles between the line connecting the boundary node of the stress concentration zone and the borehole reference point and the horizontal plane; thereby achieving a quantitative characterization of the spatial morphology and expansion range of the stress concentration zone in the advanced support.

[0025] In step S104, the stress sensor installation scheme is determined based on spatial distribution parameters. Specifically, the directional monitoring range can be determined based on the directional distance between the stress concentration area of ​​the pre-support and the roadway, the burial depth of the monitoring borehole can be determined based on the vertical distance, and the construction angle of the monitoring borehole can be determined based on the included angle range. The construction angle can include the construction depression angle and the construction elevation angle, so that the monitoring borehole can extend into the interior of the stress concentration area of ​​the pre-support. Furthermore, the construction area of ​​the monitoring borehole can be limited according to the spatial range of the stress concentration area of ​​the pre-support, thereby improving the targeting and monitoring effectiveness of the stress sensor placement.

[0026] In step S105, monitoring boreholes are constructed in the roadway according to the stress sensor installation plan, and stress sensors are installed in the monitoring boreholes. Specifically, monitoring boreholes can be constructed within a preset range of the stress concentration zone of the pre-support ahead of the working face, and the construction angle of the monitoring boreholes is controlled to be within the angle range between the stress concentration zone of the pre-support and the horizontal direction. After the monitoring borehole construction is completed, at least two stress sensors are installed in the monitoring boreholes, one stress sensor is installed at a shallow base point, and the other stress sensor is installed at a deep base point, so as to realize stress monitoring in different depth areas. Further, the maximum installation depth of the stress sensor can be controlled to be less than the distance between the roadway and the edge of the stress concentration zone of the pre-support, and the installation direction of the stress sensor can be adjusted so that its force direction is perpendicular to the direction of the maximum principal stress, thereby improving the accuracy and reliability of the pre-support stress monitoring data of the near-vertical coal seam.

[0027] The embodiments in this application disclose a method for testing the pre-support stress in near-vertical coal seams. A numerical simulation model of near-vertical coal seam mining is constructed based on geological and mining parameters to simulate the coal seam recovery process and determine the pre-support stress concentration zone ahead of the working face. Furthermore, spatial distribution parameters are determined based on the spatial distribution characteristics of the pre-support stress concentration zone, and a stress sensor installation plan is formulated according to these parameters. Monitoring boreholes are drilled in the roadway, and stress sensors are installed to achieve accurate monitoring of the pre-support stress in near-vertical coal seams. This method effectively solves the problem that traditional fixed monitoring methods are difficult to adapt to the inclined and asymmetrical distribution of pre-support stress in near-vertical coal seams, improves the accuracy of stress sensor placement and the reliability of monitoring data, thereby enhancing the accuracy and engineering applicability of near-vertical coal seam rockburst monitoring and early warning.

[0028] In one embodiment, after installing the stress sensor in the monitoring borehole, the method further includes: During coal seam mining, the stress sensor is monitored in real time, and its position is adjusted based on changes in the spatial distance between the stress sensor and the working face and / or changes in stress monitoring values.

[0029] In this embodiment, the working face refers to the mining area that is being advanced during coal seam mining, and its location moves forward continuously as mining progresses. A stress sensor is a monitoring device used to sense changes in stress within the coal seam. It can convert changes in surrounding rock stress into collectable electrical signals or physical quantities, and can be a coal stress gauge.

[0030] This embodiment achieves dynamic adjustment of the sensor's working position by continuously monitoring the stress sensor installed in the monitoring borehole and combining this with changes in the spatial distance between the stress sensor and the working face during the face advance, as well as changes in the stress monitoring values. When a gradual decrease in spatial distance or a change in stress response characteristics is detected, it indicates that the current stress sensor has gradually deviated from the main area of ​​action of the advanced support stress or entered the stress attenuation region. Therefore, it is necessary to adjust its spatial position to place it back within a more representative stress concentration influence range, ensuring that the monitoring data always reflects the stress evolution characteristics of the key area.

[0031] This embodiment ensures that the stress monitoring location remains aligned with the critical stress area as the working face advances, preventing fixed deployments from causing monitoring points to remain in stress attenuation zones or deviate from principal stress concentration zones for extended periods. This improves the sensitivity and accuracy of the monitoring data to actual stress changes. Simultaneously, this method reduces data distortion caused by monitoring location failures, enhances the continuity and reliability of the stress evolution process in the advanced support, and provides a more stable data foundation for subsequent rockburst risk assessment.

[0032] In one embodiment, adjusting the position of the stress sensor based on changes in the spatial distance between the stress sensor and the working surface and / or changes in stress monitoring values ​​specifically includes: The stress sensor located in front of the working surface and closest to the working surface is used as the sensor to be transferred. When the distance between the sensor to be transferred and the working surface is less than a preset distance threshold, and / or the stress monitoring value of the sensor to be transferred drops to the preset threshold range after reaching its peak value, the sensor to be transferred is disassembled and recycled. The disassembled sensor to be transferred is installed at the leading edge monitoring position of the stress concentration zone of the advanced support in front of the working face.

[0033] In this embodiment, spatial distance change refers to the increase or decrease in distance between the stress sensor and the working face as the mining progresses. The sensor to be transferred refers to the stress sensor currently closest to the working face in the monitoring system, whose monitoring status meets the migration conditions. The leading edge monitoring position is the monitoring area located at the forefront of the stress concentration zone of the advanced support in the direction of working face advancement, enabling the reinstalled stress sensor to prioritize monitoring the area ahead of the working face that is about to enter a stress concentration state.

[0034] This embodiment selects the stress sensor located closest to the working face as the sensor to be transferred, and makes a joint judgment based on the changes in the spatial distance between the sensor and the working face and the changes in stress monitoring values. When the sensor to be transferred gradually approaches a preset distance threshold as the working face advances, it indicates that the stress sensor has gradually approached the leading edge boundary of the current monitoring coverage. At the same time, when its monitoring value reaches a peak and then declines and falls back to the preset threshold range, it indicates that the sensor has moved away from or is gradually withdrawing from the core area of ​​the stress concentration effect of the advanced support. Based on the above dual-condition triggering mechanism, the stress sensor is disassembled and retrieved, and reinstalled at the leading edge monitoring position of the stress concentration area of ​​the advanced support in front of the working face, so that the monitoring node is always located in the key leading edge area of ​​the stress concentration area, thereby achieving continuous optimization and forward movement of the monitoring position.

[0035] In one embodiment, the preset distance threshold is 20m, and the preset threshold range is 1.2 times or less of the initial stable value of the measuring point. When the above migration conditions are met, the set of stress sensors is disassembled and recycled. The set of stress sensors includes two stress sensors respectively set at the shallow base point and the deep base point. Subsequently, the installation position is re-determined at the foremost point of the existing monitoring area, keeping it within ±10m of the stress concentration area of ​​the working face's advance support. According to the stress sensor installation plan determined in step S104, the monitoring borehole is reconstructed and the set of stress sensors is installed, so that the effective monitoring range continues to roll forward as the working face advances, ensuring that the key advance support stress concentration area in front of the working face is always under continuous and stable monitoring coverage throughout the entire mining process.

[0036] In one embodiment, during coal seam mining, the stress sensor is monitored in real time, specifically including: Collect stress monitoring values ​​from each of the stress sensors located in front of the workpiece; Obtain the original monitoring values ​​corresponding to each stress sensor; The stress state of the corresponding area is determined based on the stress monitoring values ​​and the original monitoring values. When the stress monitoring value is greater than or equal to 1.5 times the original monitoring value and less than 1.75 times the original monitoring value, the corresponding area is identified as an early warning state, and the area where the stress monitoring value exceeds the limit is subject to key monitoring. When the stress monitoring value is greater than or equal to 1.75 times the original monitoring value, the corresponding area is identified as a dangerous state, and pressure relief measures are taken for the corresponding area.

[0037] In this embodiment, the original monitoring value refers to the baseline stress value collected after the stress sensor is installed and enters a stable working state, before the coal seam is significantly affected by mining. It reflects the original rock stress state at the corresponding monitoring location under initial conditions. Due to differences in burial depth, surrounding rock structure, and stress environment at different monitoring locations, the original monitoring values ​​corresponding to each stress sensor may also differ. Stress state refers to the classification of the current area's stress hazard level based on the degree of change of the real-time stress monitoring value relative to the original monitoring value, including warning state and hazardous state. Decompression measures refer to engineering treatment measures such as drilling to release the energy accumulated inside local high-stress areas, thereby reducing the risk of dynamic disasters such as rockbursts.

[0038] This embodiment utilizes the ratio between real-time stress changes and original stress to dynamically identify the degree of danger of pre-support stress ahead of the working face. This is because during the mining process of near-vertical coal seams, stress within the coal and rock mass ahead of the working face will continuously redistribute, thus the stress in different areas will continuously change as the working face advances. The system continuously collects real-time stress monitoring values ​​from various stress sensors and compares them with the original monitoring values ​​at the corresponding locations, thereby reflecting the changes in the current stress concentration level in the area.

[0039] When the real-time stress value reaches 1.5 times but less than 1.75 times the original monitoring value, it indicates that the area has entered a significant stress concentration stage, but has not yet reached a highly dangerous level. Therefore, the system classifies the area as an early warning state and implements focused monitoring of the area to improve the ability to identify subsequent rapid stress increases.

[0040] When the real-time stress value reaches or exceeds 1.75 times the original monitoring value, it indicates that a high degree of stress concentration has formed in the area, the energy storage inside the coal and rock mass has increased significantly, and the risk of dynamic instability has increased significantly. At this time, the system determines the area to be in a dangerous state and takes timely pressure relief measures to reduce the impact risk by releasing the energy accumulated in the local high-stress area.

[0041] This embodiment establishes a hierarchical monitoring mechanism based on the multiple relationship of the original monitoring values, enabling dynamic identification of the stress evolution process of the pre-support. This allows the system to not only detect areas of abnormal stress growth but also differentiate between different hazard levels based on the degree of stress increase, thereby improving the accuracy of disaster early warning. Since different response strategies correspond to early warning and hazard states, a progressive risk control approach can be implemented. Compared to a single threshold alarm mechanism, this avoids misjudgments caused by short-term stress fluctuations, improving the operational stability of the monitoring system.

[0042] In another embodiment, the near-vertical coal seam mining numerical simulation model includes numerically simulated stress values ​​and original rock stress values; The numerical simulation model for near-vertical coal seam mining simulates the coal seam recovery process and determines the stress concentration zone of the advance support ahead of the working face, specifically including: Based on the numerical simulation stress value and the original rock stress value, the stress concentration factor at each location in the numerical simulation model is determined; If the stress concentration factor is greater than the preset critical threshold factor, the corresponding region will be determined as the advanced support stress concentration zone.

[0043] In this embodiment, the numerically simulated stress value refers to the stress result obtained by simulating the stress state of the surrounding rock and coal body at various locations during coal seam mining using a near-vertical coal seam mining numerical simulation model. It reflects the stress distribution inside the rock strata under mining disturbance conditions. The original rock stress value refers to the natural initial stress state of the coal seam before mining disturbance, formed by the combined action of the overlying rock strata's self-weight and geological structure. The stress concentration factor is a parameter used to characterize the degree of stress enhancement during mining in a certain area. It is determined by the ratio between the numerically simulated stress value and the original rock stress value, and is used to measure the increase in stress after mining relative to the original state. The preset critical threshold coefficient is a judgment threshold used to determine whether a certain area has entered a high stress concentration state. Its value can be set according to the coal seam burial depth, coal and rock mass strength, and impact hazard level, and can be 1.2~1.8.

[0044] This embodiment utilizes a near-vertical coal seam mining numerical simulation model to analyze stress changes at different spatial locations during coal seam mining and identifies high-stress areas using stress concentration factors. Specifically, during coal seam mining, the advancement of the working face disrupts the original stress balance, leading to a significant increase in stress in some areas ahead of the working face. By obtaining the numerically simulated stress values ​​at each location and calculating the ratio with the corresponding original rock stress values, the stress concentration factor at each location can be obtained. When the stress concentration factor in a certain area exceeds a preset critical threshold coefficient, it indicates that the area is significantly affected by mining, and the stress is significantly higher than the original stable state. Therefore, this area is identified as the pre-support stress concentration zone.

[0045] This embodiment introduces a stress concentration factor as the criterion for determining the stress concentration zone of the advanced support, which can avoid the subjectivity problems existing in the traditional empirical judgment method and improve the accuracy of high-stress area identification. At the same time, by comparing the numerically simulated stress value with the original rock stress value, the influence of mining disturbance on the stress field can be more realistically reflected, making the determined stress concentration zone of the advanced support closer to the actual situation, providing a reliable basis for the subsequent deployment of monitoring equipment, and improving the effectiveness and credibility of the overall monitoring results.

[0046] In one embodiment, the spatial distribution features include the spatial coordinate data of the boundary nodes of the advanced support stress concentration zone; The spatial distribution parameters include the directional distance between the stress concentration area of ​​the advanced support and the roadway, the vertical distance between the stress concentration area of ​​the advanced support and the roadway, and the range of the angle between the stress concentration area of ​​the advanced support and the horizontal direction. The determination of the spatial distribution parameters of the stress concentration zone of the advanced support based on its spatial distribution characteristics specifically includes: Obtain the spatial coordinate data of the boundary nodes of the stress concentration zone of the advanced support; Based on the spatial coordinate data of the boundary nodes, calculate the distance of the advanced support stress concentration zone relative to the roadway, the vertical distance relative to the roadway, and the range of the included angle relative to the horizontal direction. The vertical distance includes the maximum extension height of the top plate and the maximum extension depth of the bottom plate; The included angle range includes the maximum and minimum included angle values ​​of the line connecting the boundary node of the advanced support stress concentration zone and the preset reference point relative to the horizontal plane.

[0047] In this embodiment, the spatial coordinate data of the boundary nodes refers to the position data of the nodes at the outer boundary of the stress concentration zone of the advanced support in three-dimensional space, including the coordinate information of the nodes in the strike direction, vertical direction, and horizontal dip direction, used to characterize the actual spatial shape of the stress concentration zone of the advanced support. The strike distance refers to the spatial positional relationship of the stress concentration zone of the advanced support relative to the roadway along the working face advance direction or the roadway strike direction, used to describe the distribution range of the stress concentration zone in the strike direction. The vertical distance refers to the vertical spatial distance of the stress concentration zone of the advanced support relative to the roadway roof or floor, including the maximum extension height of the roof and the maximum extension depth of the floor, used to describe the vertical expansion scale of the stress concentration zone. The included angle range refers to the range of angle variation of the line connecting the boundary node of the stress concentration zone of the advanced support and the preset reference point relative to the horizontal plane, which is composed of the maximum included angle value and the minimum included angle value, used to characterize the spatial tilt characteristics of the stress concentration zone relative to the horizontal plane. The preset reference point is the benchmark position used for spatial angle calculation, and can be set as the drilling construction position or monitoring layout reference position in the roadway.

[0048] This embodiment transforms the stress concentration zone of the advanced support into spatial parameters that can be quantified and calculated. First, the spatial coordinate data of the boundary nodes of the stress concentration zone of the advanced support are obtained. By analyzing the positional relationship of each boundary node, the spatial distribution parameters of the stress concentration zone of the advanced support relative to the roadway are calculated.

[0049] In the direction of travel, by analyzing the distribution range of boundary nodes on the travel coordinates, the distance of the stress concentration zone of the advance support relative to the travel path is determined, thus clarifying the influence area of ​​the stress concentration zone in front of the working face. In the vertical direction, by extracting the spatial positional relationship of the boundary nodes relative to the roof and floor of the travel path, the maximum extension height of the roof and the maximum extension depth of the floor are calculated to characterize the extent of the expansion of the stress concentration zone towards the roof and floor. In terms of spatial attitude, a preset reference point is used as the angle calculation benchmark. The angle between the line connecting each boundary node and the reference point and the horizontal plane is calculated, and the maximum and minimum angle values ​​are extracted to form an angle range, which is used to reflect the overall tilt trend of the stress concentration zone of the advance support.

[0050] This embodiment utilizes the spatial coordinate data of boundary nodes to calculate the spatial distribution parameters of the stress concentration zone in the advanced support system. This allows for a more accurate reflection of the actual location, expansion scale, and spatial tilt state of the stress concentration zone under near-vertical coal seam conditions, avoiding the inadequacy of traditional experience-based judgment methods in representing complex spatial morphologies. Furthermore, the introduction of the maximum extension height of the roof, the maximum extension depth of the floor, and the included angle range provides a clear quantitative basis for the spatial boundary of the stress concentration zone in the advanced support system. This improves the accuracy and repeatability of the spatial positioning results, providing a reliable parameter foundation for subsequent monitoring layout, borehole design, and sensor installation.

[0051] In one embodiment, a spatial coordinate set Pi(xi,yi, zi) is established for the boundary node of a certain advanced support stress concentration zone, and a spatial coordinate reference system is established with the center of the roadway floor as the coordinate origin. The direction of the direction is set as the Y-axis, the vertical direction is set as the Z-axis, and the horizontal direction is set as the X-axis. At the same time, the current working face position coordinate Y0, the roadway roof elevation Zroof, and the roadway floor elevation Zfloor are used as spatial reference references.

[0052] The spatial scale parameters of the stress concentration zone in the advanced support are then calculated. Specifically, in the strike direction, extreme value analysis of the distribution of boundary node yi is used to determine the starting distance Ystart=min(yi)-Y0 and the ending distance Yand=max(yi)-Y0 in front of the working face of the stress concentration zone in the advanced support, thus clarifying its spatial coverage along the strike direction. In the vertical direction, by extracting the spatial positional relationship of boundary node zi relative to the roadway roof and floor, the maximum extension height Hmax=max(zi)-Zroof of the roof stress concentration zone and the maximum extension depth Dmax=Zfloor-min(zi) of the floor stress concentration zone are calculated to characterize the vertical expansion scale of the stress concentration zone.

[0053] Meanwhile, using the coordinates (xd, zd) of the reference point for drilling within the tunnel as the benchmark for spatial angle calculation, the angle θi = arctan(|xi-xd| / |zi-zd|) between the line connecting each boundary node and the reference point and the horizontal plane is calculated. Statistical analysis is then performed on all θi values ​​to obtain the following formula for the range of angles: ; The included angle range is [θmin, θmax], where θmin = min(θi) and θmax = max(θi). Through the above calculation process, the originally discrete three-dimensional boundary node information is transformed into parameters that can be applied in engineering, such as directional distance, vertical extension scale, and spatial included angle range. This enables a precise quantitative expression of the spatial morphology of the stress concentration area of ​​the advanced support, providing a reliable spatial basis for subsequent monitoring and layout.

[0054] In another embodiment, the spatial distribution parameters include the directional distance between the pre-support stress concentration area and the roadway, the vertical distance between the pre-support stress concentration area and the roadway, and the range of the angle between the pre-support stress concentration area and the horizontal direction. The step of determining the stress sensor installation scheme based on the spatial distribution parameters specifically includes: The direction monitoring range is determined based on the stated direction distance; The burial depth of the monitoring borehole is determined based on the vertical distance. The construction angle of the monitoring borehole is determined based on the included angle range; The stress sensor installation scheme is determined based on the described direction monitoring range, the described burial depth, and the described construction angle.

[0055] In this embodiment, the spatial distribution parameters of the stress concentration zone in the advanced support are transformed into constraints for engineering layout. Mapping the strike distance to the strike monitoring range determines the coverage area of ​​the monitoring system in the roadway direction, thereby avoiding monitoring blind spots. By mapping the vertical distance to the burial depth of the monitoring borehole, the sensors can accurately enter the extension range of the roof or floor of the stress concentration zone, thereby obtaining real stress change information. By mapping the included angle range to the construction angle of the monitoring borehole, the deployment direction of the stress sensors matches the spatial tilt characteristics of the stress concentration zone, thereby improving the response capability to changes in the principal stress direction.

[0056] This embodiment maps the strike distance, vertical distance, and included angle range, transforming the stress sensor arrangement from the traditional fixed-parameter arrangement to one tailored to the actual spatial morphology of the stress concentration zone in the advanced support. This significantly improves the spatial overlap between monitoring points and high-stress areas, reduces measurement distortion caused by arrangement deviations, and enhances the accuracy and stability of identifying complex stress fields in near-vertical coal seams. Furthermore, since the monitoring borehole angle and depth are determined based on actual spatial distribution parameters, the problem of stress sensors failing to enter effective stress zones or crossing stress concentration boundaries is effectively avoided, improving data validity.

[0057] In one embodiment, the starting and ending distances [Ystart, Yend] of the strike of the stress concentration zone in the advanced support are first obtained. Based on this, to avoid insufficient monitoring coverage due to mining advance errors or stress propagation uncertainties, a strike safety redundancy margin ΔY is introduced, and the strike monitoring range is set to [Ystart]. [ΔY, Yend+ΔY], thereby forming a moderately extended monitoring coverage area in the direction before and after the stress concentration area, enabling the monitoring system to fully cover the transition area of ​​stress evolution and improve the boundary identification capability.

[0058] In the vertical direction, by extracting the extreme values ​​of the coordinate points in the vertical direction and subtracting the elevations of the roadway roof and floor respectively, the maximum extension height Hmax of the stress concentration zone above the roof and the maximum extension depth Dmax below the floor can be calculated, thus forming a quantitative description of the vertical influence range.

[0059] Furthermore, in terms of borehole construction angle design, based on the included angle range [θmin, θmax] of the stress concentration zone of the advanced support, in order to match the monitoring direction with the spatial distribution direction of the principal stress and to ensure that stress gauge elements such as hydraulic pillows are as perpendicular as possible to the principal stress direction to improve stress sensitivity, the borehole construction elevation angle or depression angle α is set as the median value of the included angle range, i.e., α=(θmin+θmax) / 2, and α satisfies θmin≤α≤θmax, so that the monitoring direction is located within the main spatial tendency range of the stress concentration zone, thereby improving the representativeness and stability of the measurement.

[0060] Regarding the design of the burial depth, to ensure that the stress gauge deep reference point can be stably located inside the stress concentration zone and avoid penetrating its outer boundary, the installation hole depth L is determined based on the spatial distance relationship between the centroid coordinates (xc, zc) of the concentration zone and the drilling construction reference point (xd, zd). The calculation formula is as follows: ; In conjunction with the vertical boundary constraints, the vertical projection depth of the borehole must not exceed the calculated Hmax or Dmax to prevent the sensor placement from exceeding the effective range of the stress concentration zone of the advanced support, thereby ensuring that the monitoring data comes from the real high-stress area and improving the validity and reliability of the data.

[0061] In another embodiment, the stress sensor installation scheme includes monitoring the drilling angle, burial depth, and orientation range of the borehole; The step of constructing monitoring boreholes in the roadway according to the stress sensor installation scheme, and installing stress sensors in the monitoring boreholes, specifically includes: Within the preset range of the pre-support stress concentration zone, the monitoring borehole is constructed according to the construction angle and the burial depth of the monitoring borehole; At least two stress sensors are installed in the monitoring borehole, located at the shallow base point and the deep base point, respectively. Adjust the stress sensor so that its installation depth is less than the distance between the roadway and the edge of the stress concentration area of ​​the advanced support, and the force direction of the stress sensor is perpendicular to the horizontal stress direction.

[0062] In this embodiment, a shallow baseline refers to the installation position of the stress sensor located on the side of the monitoring borehole relatively close to the roadway, used to monitor stress changes in the outer edge or shallow area of ​​the stress concentration zone of the advanced support. A deep baseline refers to the installation position of the stress sensor located at a deeper position in the monitoring borehole, used to monitor stress changes in the core area inside the stress concentration zone of the advanced support. The construction angle refers to the elevation or depression angle of the monitoring borehole relative to the roadway horizontal plane, used to control the spatial direction of the monitoring borehole entering the stress concentration zone of the advanced support. The burial depth refers to the distance the stress sensor travels along the direction of the monitoring borehole into the coal and rock mass, used to ensure that the sensor is within the effective stress area. The horizontal stress direction refers to the dominant horizontal principal stress direction under near-vertical coal seam conditions. Due to the combined influence of gravity and bedding structure on near-vertical coal seams, horizontal stress often becomes the main controlling stress in the stress concentration zone of the advanced support.

[0063] In this embodiment, within a preset range of the stress concentration zone of the advanced support, monitoring drilling is carried out according to the construction angle and burial depth to ensure that the drilling spatial direction matches the actual tilt direction of the stress concentration zone of the advanced support, thereby ensuring that the drilling can pass through the effective area of ​​the stress concentration zone, rather than deviating from the high stress area.

[0064] Subsequently, two stress sensors, one shallow and one deep, were installed within the same monitoring borehole. The shallow sensor was used to detect stress changes at the edge of the stress concentration zone, while the deep sensor was used to detect stress evolution in the core area of ​​the stress concentration zone. This is because the pre-support stress exhibits a spatial distribution characteristic of gradually increasing from the outside to the inside. Therefore, the dual-sensor structure enables continuous monitoring of stress gradient changes, thereby improving the accuracy of identifying the pre-support stress evolution pattern.

[0065] Furthermore, limiting the installation depth of the stress sensor to less than the distance between the roadway and the edge of the stress concentration zone of the advance support can prevent the borehole from penetrating the outer boundary of the stress concentration zone, thus preventing the sensor from entering a low-stress area and causing distorted monitoring results. Simultaneously, by adjusting the force direction of the stress sensor to be perpendicular to the horizontal stress direction, the stress-bearing components such as the hydraulic cushion of the stress sensor can obtain a more significant response, thereby improving the sensitivity to stress changes and the measurement stability.

[0066] This embodiment ensures that the spatial orientation, burial depth, and sensor force direction of the monitoring borehole are all adapted to the spatial structure of the stress concentration zone of the advanced support, thereby improving the spatial matching degree between the sensor and the high-stress area. Compared with the traditional fixed-depth or fixed-angle arrangement, it can effectively reduce the problem of sensor deviation from the principal stress area and improve the authenticity and continuity of monitoring data. Through the dual-point monitoring structure of shallow and deep base points, stress change information of the outer edge and core area of ​​the stress concentration zone of the advanced support can be obtained simultaneously, thereby more accurately reflecting the spatial evolution process of stress from low to high and improving the ability to identify impact hazard areas.

[0067] like Figure 2 As shown, a flowchart of a method for testing the pre-support stress of a near-vertical coal seam in one embodiment of this application is presented, including: S201: Based on the geological and mining parameters of the target near-vertical coal seam, construct a numerical simulation model for mining near-vertical coal seams; S202: The numerical simulation model for near-vertical coal seam mining includes numerical simulation stress values ​​and original rock stress values; based on the numerical simulation stress values ​​and the original rock stress values, the stress concentration factor at each location in the numerical simulation model is determined; S203: If the stress concentration factor is greater than the preset critical threshold factor, the corresponding area will be determined as the advanced support stress concentration area; S204: Obtain the spatial coordinate data of the boundary nodes of the stress concentration zone of the advanced support; S205: Based on the spatial coordinate data of the boundary nodes, calculate the distance of the advanced support stress concentration zone relative to the roadway, the vertical distance relative to the roadway, and the range of the included angle relative to the horizontal direction. S206: Determine the direction monitoring range based on the stated direction distance; S207: Determine the burial depth of the monitoring borehole based on the vertical distance; S208: Determine the construction angle of the monitoring borehole based on the included angle range; S209: Determine the stress sensor installation scheme based on the described direction monitoring range, the described burial depth, and the described construction angle; S210: Within the preset range of the pre-support stress concentration zone, the monitoring borehole is constructed according to the construction angle and the burial depth of the monitoring borehole; S211: Install at least two stress sensors in the monitoring borehole, located at the shallow base point and the deep base point respectively; S212: Adjust the stress sensor so that the installation depth of the stress sensor is less than the distance between the roadway and the edge of the stress concentration area of ​​the advanced support, and the force direction of the stress sensor is perpendicular to the horizontal stress direction. S213: During the coal seam mining process, the stress sensor is monitored in real time, and the position of the stress sensor is adjusted according to the changes in the spatial distance between the stress sensor and the working face and / or the changes in the stress monitoring values; S214: The stress sensor located in front of the working surface and closest to the working surface is used as the sensor to be transferred; S215: When the distance between the sensor to be transferred and the working surface is less than a preset distance threshold, and / or the stress monitoring value of the sensor to be transferred drops to the preset threshold range after reaching the peak value, the sensor to be transferred shall be disassembled and recycled. S216: Install the disassembled sensor to be transferred at the leading edge monitoring position of the stress concentration zone of the advanced support in front of the working face.

[0068] like Figure 3 As shown, in one specific embodiment, in the B3-6 working face of a near-vertical coal seam in a certain coal mine, the coal seam dip angle is 87°, the working face is located at an elevation of +425 m, and the segmented mining height is 25 m.

[0069] In step S101, basic field data is first obtained based on the geological and mining parameters of the near-vertical coal seam, and a numerical simulation model of near-vertical coal seam mining is constructed using FLAC3D numerical simulation software. In the numerical simulation model, the roof and floor strata are defined as weak-plane structures controlled by bedding planes to reflect the mechanical characteristics of the surrounding rock in near-vertical coal seams, which are prone to slippage and bending along bedding planes. By simulating the layered mining process of the coal seam, the dynamic distribution of stress in the surrounding rock ahead of the working face is obtained, and the numerical simulation stress value and the original rock stress value are extracted. Based on the stress concentration factor... In this embodiment, the critical threshold coefficient k is set to 1.5. When λs is greater than 1.5, the corresponding area is identified as the stress concentration area of ​​the advanced support, thus obtaining the high stress concentration core area that is inclined and asymmetrically distributed above B3 roadway and below B6 roadway.

[0070] In step S102, based on the spatial distribution results of the stress concentration zone of the advance support obtained from numerical simulation, the stress field of the stress concentration zone of the advance support during coal seam mining is analyzed and extracted. By statistically analyzing the spatial coordinates of the boundary nodes of the stress concentration area, the spatial location and morphological characteristics of the stress rise zone in front of the working face are clarified, thereby determining the spatial distribution characteristics of the stress concentration zone of the advance support.

[0071] In step S103, based on the spatial distribution characteristics, the coordinates of the boundary nodes are processed to calculate the spatial distribution parameters of the stress concentration zone of the advanced support. Specifically, this includes: determining the stress influence range in the direction of travel to be approximately 5 m to 35 m in front of the working face; determining the maximum extension height of the top plate to be approximately 15 m and the maximum extension depth of the bottom plate to be approximately 10 m in the vertical direction; and simultaneously calculating the angle between the boundary node and the reference point and the horizontal direction to be between 11° and 44°, thereby forming a spatial scale description of the concentration zone.

[0072] In step S104, a stress sensor installation plan is formulated based on the aforementioned spatial distribution parameters. Specifically, the monitoring range is set to cover the area from -5 m to 45 m in front of the working face to ensure that the monitoring range covers the stress concentration zone evolution area; the drilling angle is set to the median of the included angle range, 27.5°, so that the monitoring direction is closer to the direction of principal stress; and the drilling depth is set to approximately 14 m to ensure that the monitoring end can enter the core area of ​​high stress concentration.

[0073] In step S105, monitoring boreholes are constructed in the B3 and B6 longwall mining roadways according to the installation plan, and stress sensors are installed in the boreholes. The boreholes are spaced 2 m apart, with two stress sensors installed in each group of boreholes, positioned at a 7 m shallow baseline and a 13 m deep baseline, respectively, to achieve synchronous monitoring of stress evolution at different depths. Simultaneously, by controlling the installation posture, the stress sensor's force direction is kept perpendicular to the predominantly horizontal principal stress direction in the near-vertical coal seam, thereby improving stress response sensitivity.

[0074] During coal seam mining, the system monitors each stress sensor in real time, continuously collecting stress change data ahead of the working face, and comparing and analyzing this data with the original monitoring values ​​at each measuring point. Different states are defined based on the stress ratio: when the monitored stress value is more than 1.5 times but less than 1.75 times the original monitored value, it is considered a warning state, and the area is subject to focused monitoring; when the monitored stress value reaches or exceeds 1.75 times the original monitored value, it is considered a dangerous state, triggering pressure relief measures. This tiered judgment method enables layered identification and risk control of the stress evolution process in near-vertical coal seams.

[0075] Figure 4 An electronic device according to this application is shown, comprising: At least one processor 401; and, Memory 402 is communicatively connected to at least one processor 401; wherein, The memory 402 stores instructions that can be executed by at least one processor 401, which enables the at least one processor 401 to perform all the steps of a test method for the pre-support stress of a near-vertical coal seam in any of the foregoing method embodiments.

[0076] Figure 4 Taking a processor 401 as an example: The electronic device may also include an input device 403 and an output device 404.

[0077] The processor 401, memory 402, input device 403 and output device 404 can be connected by a bus or other means. The figure shows an example of connection by bus.

[0078] Memory 402, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to a method for testing the pre-support stress of near-vertical coal seams in an embodiment of this application. Figure 1 and Figure 2 The method flow is shown. The processor 401 executes various functional applications and data processing by running non-volatile software programs, instructions, and modules stored in the memory 402, thereby realizing a method for testing the pre-support stress of near-vertical coal seams in the above embodiments.

[0079] Memory 402 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created using a method for testing the pre-support stress of near-vertical coal seams. Furthermore, memory 402 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state memory device. In some embodiments, memory 402 may optionally include memory remotely located relative to processor 401, and this remote memory may be connected via a network to apparatus for performing a method for testing the pre-support stress of near-vertical coal seams. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0080] The input device 403 can receive user clicks and generate signal inputs related to user settings and function control for the test method of pre-support stress in near-vertical coal seams. The output device 404 may include a display screen or other display device.

[0081] One or more modules are stored in memory 402, and when run by one or more processors 401, they execute a method for testing the pre-support stress of near-vertical coal seams in any of the above method embodiments.

[0082] Embodiments of this application also provide a computer program product, including a computer program / instructions that, when executed by a processor, implement a method for testing the advanced support stress of a near-vertical coal seam as described in any of the preceding embodiments.

[0083] As needed, the above technical solutions can be combined to achieve the best technical effect.

[0084] The above description is merely the principle and preferred embodiment of this application. It should be noted that for those skilled in the art, implementation methods obtained by appropriately combining the technical solutions disclosed in different embodiments are also included within the technical scope of this invention. Based on the principle of this application, several other modifications can also be made, which should also be considered within the protection scope of this application.

Claims

1. A method for testing the advanced support stress in near-vertical coal seams, characterized in that, include: Based on the geological and mining parameters of the target near-vertical coal seam, a numerical simulation model for mining near-vertical coal seams is constructed. Based on the numerical simulation model of near-vertical coal seam mining, the coal seam mining process is simulated to determine the stress concentration zone of the advance support in front of the working face. Based on the spatial distribution characteristics of the stress concentration area of ​​the advanced support, the spatial distribution parameters of the stress concentration area of ​​the advanced support are determined; Based on the spatial distribution parameters, determine the stress sensor installation scheme; According to the stress sensor installation scheme, a monitoring borehole is constructed in the roadway, and a stress sensor is installed in the monitoring borehole.

2. The method for testing the advanced support stress of a near-vertical coal seam according to claim 1, characterized in that, After installing the stress sensor in the monitoring borehole, the method further includes: During coal seam mining, the stress sensor is monitored in real time, and its position is adjusted based on changes in the spatial distance between the stress sensor and the working face and / or changes in stress monitoring values.

3. The method for testing the advanced support stress of a near-vertical coal seam according to claim 2, characterized in that, The step of adjusting the position of the stress sensor based on changes in the spatial distance between the stress sensor and the working surface and / or changes in stress monitoring values ​​specifically includes: The stress sensor located in front of the working surface and closest to the working surface is used as the sensor to be transferred. When the distance between the sensor to be transferred and the working surface is less than a preset distance threshold, and / or the stress monitoring value of the sensor to be transferred drops to the preset threshold range after reaching its peak value, the sensor to be transferred is disassembled and recycled. The disassembled sensor to be transferred is installed at the leading edge monitoring position of the stress concentration zone of the advanced support in front of the working face.

4. The method for testing the advanced support stress of a near-vertical coal seam according to claim 1, characterized in that, The numerical simulation model for near-vertical coal seam mining includes numerical simulation stress values ​​and original rock stress values; The numerical simulation model for near-vertical coal seam mining simulates the coal seam recovery process and determines the stress concentration zone of the advance support ahead of the working face, specifically including: Based on the numerical simulation stress value and the original rock stress value, the stress concentration factor at each location in the numerical simulation model is determined; If the stress concentration factor is greater than the preset critical threshold factor, the corresponding region will be determined as the advanced support stress concentration zone.

5. The method for testing the advanced support stress of a near-vertical coal seam according to claim 1, characterized in that, The spatial distribution characteristics include the spatial coordinate data of the boundary nodes of the advanced support stress concentration zone; The spatial distribution parameters include the directional distance between the stress concentration area of ​​the advanced support and the roadway, the vertical distance between the stress concentration area of ​​the advanced support and the roadway, and the range of the angle between the stress concentration area of ​​the advanced support and the horizontal direction. The determination of the spatial distribution parameters of the stress concentration zone of the advanced support based on its spatial distribution characteristics specifically includes: Obtain the spatial coordinate data of the boundary nodes of the stress concentration zone of the advanced support; Based on the spatial coordinate data of the boundary nodes, calculate the distance of the advanced support stress concentration zone relative to the roadway, the vertical distance relative to the roadway, and the range of the included angle relative to the horizontal direction. The vertical distance includes the maximum extension height of the top plate and the maximum extension depth of the bottom plate; The included angle range includes the maximum and minimum included angle values ​​of the line connecting the boundary node of the advanced support stress concentration zone and the preset reference point relative to the horizontal plane.

6. The method for testing the advanced support stress of a near-vertical coal seam according to claim 1, characterized in that, The spatial distribution parameters include the directional distance between the stress concentration area of ​​the advanced support and the roadway, the vertical distance between the stress concentration area of ​​the advanced support and the roadway, and the range of the angle between the stress concentration area of ​​the advanced support and the horizontal direction. The step of determining the stress sensor installation scheme based on the spatial distribution parameters specifically includes: The direction monitoring range is determined based on the stated direction distance; The burial depth of the monitoring borehole is determined based on the vertical distance. The construction angle of the monitoring borehole is determined based on the included angle range; The stress sensor installation scheme is determined based on the described direction monitoring range, the described burial depth, and the described construction angle.

7. The method for testing the advanced support stress of a near-vertical coal seam according to claim 1, characterized in that, The stress sensor installation scheme includes monitoring the drilling angle, burial depth, and orientation range of the borehole. The step of constructing monitoring boreholes in the roadway according to the stress sensor installation scheme, and installing stress sensors in the monitoring boreholes, specifically includes: Within the preset range of the pre-support stress concentration zone, the monitoring borehole is constructed according to the construction angle and the burial depth of the monitoring borehole; At least two stress sensors are installed in the monitoring borehole, located at the shallow base point and the deep base point, respectively. Adjust the stress sensor so that its installation depth is less than the distance between the roadway and the edge of the stress concentration area of ​​the advanced support, and the force direction of the stress sensor is perpendicular to the horizontal stress direction.

8. A storage medium, characterized in that, The storage medium stores computer instructions, which, when executed by the computer, are used to perform a test method for the advanced support stress of a near-vertical coal seam as described in any one of claims 1-7.

9. An electronic device, characterized in that, Includes at least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform a test method for the pre-support stress of a near-vertical coal seam as described in any one of claims 1-7.

10. A computer program product, comprising a computer program / instructions, characterized in that, When executed by a processor, the computer program / instruction implements a method for testing the advanced support stress of a near-vertical coal seam as described in any one of claims 1-7.

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