A coal mine goaf ground subsidence monitoring method and system

Abstract

The present application provides a kind of coal mine goaf ground subsidence monitoring method and system, it is related to geological survey technical field, steps include: the data of underground point position of coal mine goaf highway is collected, the compression rate in each time vertical direction is analyzed and compared, the development stage of ground subsidence is judged;Collect the horizontal coordinate of underground point position, judge whether there is shear deformation in this layer;The synthetic movement rate of underground point position is calculated, the intensity of actual deformation movement of underground point position is judged;When judging that the deformation of this area intensifies, stability gradually loses, there is instability risk, demarcate the highway in this area as high-risk area and issue early warning, through real-time synchronous perception and dynamic trend analysis to three-dimensional deformation field underground, early identification to nonlinear accelerated deformation is realized, and high-risk area can be accurately positioned, which provides direct basis for targeted prevention and control, overcome the defects that the existing technology is slow to react to nonlinear accelerated deformation and the early warning result is general.

Description

Technical Field

[0001] This invention relates to the field of geological surveying technology, specifically to a method and system for monitoring ground subsidence in coal mine goaf areas. Background Technology

[0002] Highways built above coal mine goaf areas, as critical infrastructure connecting vital transportation arteries, bear direct damage from surface deformation. Coal mine goaf areas themselves are a major cause of ground subsidence disasters; the overlying rock strata undergo complex deformations, including vertical subsidence, horizontal displacement, and interlayer shear, during stress rebalancing. These deformations, over time, not only lead to surface road cracking and undulation but also indicate a significant risk of gradual loss of underground structural stability, potentially resulting in sudden collapse and severely threatening traffic safety and surrounding facilities. Real-time, synchronous monitoring of underground points in the goaf area in both vertical and horizontal directions, and comprehensive analysis of their combined movement trends, are crucial for accurately determining the subsidence development stage, identifying core affected areas, and providing early warnings of instability risks. This provides a scientific basis for effective prevention and control, minimizing safety risks and economic losses.

[0003] In the prior art, CN117216930B discloses a method and system for predicting the risk of land subsidence. This technology includes: dividing the areas where soil fractures or cracks occur into separate regions and predicting them by region and time period to reduce the amount of calculation required by the model at one time; and introducing vegetation index data to construct three prediction models, calculating the weight of each prediction model to improve the accuracy of land subsidence prediction, and being able to predict the occurrence of land subsidence disasters in advance, thereby reducing the harm caused by land subsidence to human life.

[0004] However, the core of the aforementioned existing technologies relies on model fitting and weighted prediction of historical data and indirect indicators such as surface vegetation indices. This approach has certain limitations in its application: it lacks monitoring of the deformation within the underground soil and rock mass of mining subsidence areas, and cannot directly capture the deformation and interaction of soil layers at different depths in the vertical and horizontal directions, resulting in a lag in the identification of key risks such as settlement center migration and shear deformation; at the same time, it is difficult to determine the core area affected by deformation and the actual intensity of movement, and the early warning results are relatively general, failing to provide an effective basis for differentiated and precise prevention and control of infrastructure such as highways.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system for monitoring ground subsidence in coal mine goaf areas, thereby addressing the problems mentioned in the background section. This invention constructs a three-dimensional monitoring system for underground space. By simultaneously collecting vertical and horizontal displacement data from points at different depths, it calculates the compression rate and horizontal displacement vector of the strata, thus accurately identifying the subsidence center and shear deformation risk. The system integrates vertical subsidence and horizontal displacement to calculate the composite motion rate at each point, quantifying the severity of deformation and precisely delineating the core affected area. The early warning mechanism is based on the dynamic trend of the composite motion rate. When the rate exceeds a threshold and the trend continues to strengthen, it immediately determines the risk of instability, achieving accurate and advanced early warning of ground subsidence in goaf areas, especially the instability risk in key areas such as above-ground highways. This effectively overcomes the shortcomings of traditional models, such as delayed early warning and ambiguous positioning.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method and system for monitoring ground subsidence in coal mine goaf areas includes the following functional modules:

[0009] S1. Collect data on underground points along roads in coal mine goaf areas. The data on these underground points are values ​​at different depths along vertical lines. Initially, the underground points are divided at equal intervals. The vertical spacing of each point is monitored and data is collected at fixed time intervals. Vertical detection of the underground points is completed, and the compression rate of the strata in the vertical direction is calculated. The compression rates in the vertical direction at different times are analyzed and compared to determine the stage of ground subsidence development.

[0010] S2. At the time node of vertical detection synchronization, the horizontal coordinates of underground points are collected synchronously, and the displacement data of the acquired horizontal coordinates are compared and analyzed to determine the location of the underground settlement center in the coal mine goaf. By comparing the horizontal coordinate displacement vector and direction between the upper and lower underground points, it is determined whether there is shear deformation on the vertical line, and a three-dimensional deformation monitoring system for underground space is constructed.

[0011] S3. By calculating the vertical settlement rate and horizontal displacement rate of the collected underground points, the final composite motion rate of the underground points is calculated, the intensity of the actual deformation motion of the underground points is determined, the spatial distribution of the composite motion rate of different underground points is analyzed, and the core area of ​​deformation influence is determined.

[0012] S4. Using the time node of vertical detection synchronization as a fixed monitoring cycle, by comparing and analyzing the synthetic motion rate of underground points, when the synthetic motion rate reaches the warning threshold and its trend shows a continuous increase, it is judged that the deformation on the vertical line is intensifying, the stability is gradually lost, and there is a risk of instability. The highway on the vertical line is designated as a high-risk area and an early warning is issued.

[0013] Furthermore, the different depth values ​​on the vertical line correspond to the data collected from three underground points, which are defined from top to bottom as point a, point b, and point c, where point a is closest to the surface and point c is the deepest. The compression rate of the strata in the vertical direction is calculated. The compression rate is the overall compression rate of the vertical profile formed by points a, b, and c. The formula for calculating the overall compression rate is:

[0014]

[0015] in , These are the depth data for points a and c at time t in the current monitoring period;

[0016] , These are the depth data for points a and c at time t-1 of the previous monitoring period, respectively.

[0017] The monitoring period is fixed in duration;

[0018] For this vertical profile at a fixed monitoring cycle duration The overall compression rate within.

[0019] Furthermore, by analyzing the overall compression rate over N consecutive fixed monitoring periods... Determine the development stage of land subsidence:

[0020] Accelerated development phase: N consecutive fixed monitoring cycles If the value continues to increase, it is determined that the settlement is in an accelerated phase;

[0021] Uniform development stage: N consecutive fixed monitoring cycles If the range of numerical increase or decrease is consistently less than 10%, then the settlement is determined to be in a uniform rate stage.

[0022] Deceleration stabilization phase: N consecutive fixed monitoring cycles If the value continues to decrease, it is determined that the settlement is in a stage of deceleration or tending to stabilize.

[0023] The value range of N is: N≥3.

[0024] Furthermore, the process for determining whether shear deformation exists on the vertical line includes: judging by analyzing the relationship between the horizontal displacements of points a, b, and c.

[0025] Calculate the relative horizontal displacement of segment ab:

[0026] Calculate the relative horizontal displacement of segment bc:

[0027] , and These are the horizontal displacement vectors of points a, b, and c during the current monitoring period t, respectively.

[0028] , and These are the horizontal displacement vectors of points a, b, and c at the current monitoring period t-1, respectively.

[0029] when or If the displacement difference exceeds the preset threshold, it is determined that the corresponding ab or bc segment has significant shear deformation.

[0030] Furthermore, the location of the underground subsidence center in the coal mine goaf is determined by analyzing the horizontal displacement vector directions of three points: point a, point b, and point c.

[0031] If the horizontal displacement vectors of points a, b, and c all point in the same direction, then points a, b, and c are located on the same side of the underground settlement center, and the common direction of the displacement vectors is the direction of the settlement center.

[0032] If the horizontal displacement vectors of points a, b, and c diverge radially, then points a, b, and c are determined to be located in the boundary region of the settlement center.

[0033] When the horizontal displacement vectors of points a, b, and c converge in a centripetal pattern, it is determined that points a, b, and c are located inside the settlement center.

[0034] By analyzing multiple horizontal displacement vector directions, the range and location of the underground settlement center can be determined in horizontal space.

[0035] Furthermore, by calculating the vertical settlement rate and horizontal displacement rate of the collected underground points, the final composite motion rate of each underground point is calculated, which includes the following steps:

[0036] For each of the points a, b, and c defined from top to bottom, calculate its vertical settlement rate and horizontal displacement rate:

[0037] The vertical settlement rate is the rate of change of depth at each point over time. For point a, the calculation formula is as follows:

[0038]

[0039] Let be the vertical settlement rate at point a;

[0040] This refers to the depth data of point a in the current monitoring period t;

[0041] The depth data for point a in the previous monitoring period t-1;

[0042] Vertical settlement rates at points b and c and The same calculation applies to the next step.

[0043] The horizontal displacement rate is the rate of change of the horizontal displacement vector at each point with time. For point a, the calculation formula is:

[0044]

[0045] Let a be the horizontal displacement rate at point a;

[0046] Let a be the horizontal displacement vector of point a during the current monitoring period t;

[0047] Let a be the horizontal displacement vector of point a in the previous monitoring cycle t-1;

[0048] Horizontal displacement rates of point b and point c and The same calculation applies to the next step.

[0049] The formula for calculating the composite velocity of point a is:

[0050]

[0051] The combined velocity of point b and point c and Calculate in the same way for the remaining steps.

[0052] Furthermore, the determination of the intensity of actual deformation movement at underground points, analysis of the spatial distribution of the composite movement rate at different underground points, and identification of the core area affected by deformation are specifically carried out as follows:

[0053] Determine the severity of deformation: Compare the calculated composite motion rate at each underground location with a preset threshold for the severity of deformation.

[0054] when < At that time, the degree of deformation at that point was determined to be slight;

[0055] when ≤ < At that time, the degree of deformation at that point was determined to be moderate;

[0056] when ≥ When the deformation at that point is deemed severe, it is determined that the deformation is severe.

[0057] in, and This is a preset threshold based on geological conditions and engineering requirements, and > .

[0058] Furthermore, the specific method for determining the core area affected by deformation is as follows: within a single monitoring period, compare the composite motion rates of various underground points along the vertical line. ;

[0059] Will The area where the points with the highest values ​​and those reaching the level of severe deformation are distributed is determined as the core area of ​​deformation impact in the current monitoring period;

[0060] By analyzing the spatiotemporal distribution and evolution trend of the core area over M consecutive monitoring periods, the direction of expansion or transfer of the subsidence impact range can be determined.

[0061] The value range of M is: M≥2.

[0062] Furthermore, the determination that deformation on the vertical line is intensifying when the synthetic motion rate reaches a warning threshold and its trend shows a continuous increase specifically includes the following steps:

[0063] For each underground point, calculate its composite motion rate. ;

[0064] when ≥ When the combined motion rate at that point reaches the warning threshold, it is determined that the combined motion rate at that point has reached the warning threshold.

[0065] Analysis of trends: Within K consecutive fixed monitoring periods, the trend of this location... If the value continues to increase, it is determined that the trend of change is continuously increasing;

[0066] The specific method for designating highways on vertical lines as high-risk zones and issuing warnings is as follows: when the combined motion rate of at least J underground points within the monitoring area reaches the warning threshold... If the trend of change shows a continuous increase, then the road on the vertical line is identified as a high-risk area;

[0067] The warning is issued based on the determination of high-risk areas, and the warning level is determined according to the maximum composite motion rate of points within the high-risk area:

[0068] When max( ) < A yellow alert will be issued at that time;

[0069] When max( )≥ At that time, a red alert was issued;

[0070] Where max( ) represents the maximum value of the composite motion velocity of the point, and the values ​​of J and K are both in the range of: J≥2, K≥2.

[0071] A coal mine goaf ground subsidence monitoring system, the monitoring system being used to execute the above-described monitoring method, the monitoring system comprising the following functional modules:

[0072] The data acquisition module collects data from underground points along roads in coal mine goaf areas. The data from these underground points are values ​​at different depths along a vertical line. Initially, the underground points are divided at equal intervals. The module monitors and collects data on the vertical spacing of each point at fixed time intervals, completing the vertical detection of the underground points, calculating the compression rate of the strata in the vertical direction, analyzing and comparing the compression rates in the vertical direction at different times, and determining the stage of ground subsidence development.

[0073] The deformation analysis module synchronously collects the horizontal coordinates of underground points at the same time node as the vertical detection, and compares and analyzes the displacement data of the acquired horizontal coordinates to determine the location of the underground settlement center in the coal mine goaf. By comparing the horizontal coordinate displacement vectors and directions between the upper and lower underground points, it determines whether there is shear deformation on the vertical line and constructs a three-dimensional deformation monitoring system for underground space.

[0074] The comprehensive evaluation module calculates the vertical settlement rate and horizontal displacement rate of the collected underground points, and finally calculates the composite motion rate of the underground points to determine the intensity of the actual deformation and movement of the underground points. It also analyzes the spatial distribution of the composite motion rate of different underground points to identify the core area affected by deformation.

[0075] The early warning response module uses the time node of vertical detection synchronization as a fixed monitoring cycle. By comparing and analyzing the synthetic motion rate of underground points, when the synthetic motion rate reaches the warning threshold and its trend shows a continuous increase, it is judged that the deformation on the vertical line is intensifying, the stability is gradually being lost, and there is a risk of instability. The highway on the vertical line is designated as a high-risk area and an early warning is issued.

[0076] Compared with the prior art, the beneficial effects of the present invention are:

[0077] This invention establishes a three-dimensional monitoring and early warning mechanism. The system, through a data acquisition module, achieves real-time, high-frequency monitoring of the vertical compression rate at different underground depths, accurately determining the development stage of ground subsidence. The deformation analysis module, by simultaneously acquiring and analyzing horizontal displacement data, not only dynamically captures the migration of the subsidence center but also directly diagnoses potential shear deformation risks through vector differences in displacement between upper and lower layers, thus constructing a three-dimensional deformation field that truly reflects the dynamics of underground space. The comprehensive evaluation module synthesizes the vertical and horizontal displacement rates into a comprehensive motion rate, quantitatively revealing the severity of underground deformation and accurately delineating the core area affected by deformation. Finally, the early warning response module makes a dual judgment based on the absolute value and dynamic trend of the synthesized motion rate. When the rate exceeds a threshold and the trend continues to increase, it is determined that the stability of the area is being lost, and a high-risk zone warning is issued for critical infrastructure such as highways.

[0078] This system enables early identification of nonlinear accelerated deformation through real-time synchronous perception and dynamic trend analysis of the underground three-dimensional deformation field, and can accurately locate high-risk areas, providing a direct basis for targeted prevention and control. It overcomes the shortcomings of existing technologies in responding slowly to nonlinear accelerated deformation and providing general early warning results. Attached Figure Description

[0079] Figure 1 This is a schematic diagram of the overall process of the method for monitoring ground subsidence in mining goaf areas according to the present invention;

[0080] Figure 2 A system block diagram for monitoring ground subsidence in mining goaf areas. Detailed Implementation

[0081] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0082] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention 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 following 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 used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0083] Example:

[0084] Please see Figures 1-2 The present invention provides a technical solution:

[0085] A method for monitoring ground subsidence in coal mine goaf areas includes the following steps:

[0086] S1. Collect monitoring data of underground points under the road in the coal mine goaf. The underground point data specifically refers to the numerical information measured at different depths along the vertical line. When initially arranged, these underground points are located by equal intervals. The system continuously monitors and collects data on the changes in the vertical spacing of each point at fixed time intervals, and calculates the vertical compression rate of the strata based on these changes. Then, by comprehensively analyzing and comparing the vertical compression rates obtained at different time points, the development stage of ground subsidence can be determined.

[0087] The numerical values ​​at different depths along the vertical line correspond to data collected from three underground points, which are defined from top to bottom as point a, point b, and point c. Point a is closest to the surface, and point c is located at the deepest point. Based on the depth information of these points, the compression rate of the strata in the vertical direction is calculated. Specifically, this compression rate refers to the overall compression rate of the vertical profile formed by points a, b, and c. The formula for calculating the overall compression rate is as follows:

[0088]

[0089] in , These are the depth data for points a and c at time t in the current monitoring period;

[0090] , These are the depth data for points a and c at time t-1 of the previous monitoring period, respectively.

[0091] The monitoring period is fixed in duration;

[0092] For this vertical profile at a fixed monitoring cycle duration The overall compression rate within, and They are inversely proportional.

[0093] By continuously analyzing the overall compression rate obtained over multiple consecutive monitoring periods The numerical trend of the change can be used to determine the specific stage of development of ground subsidence:

[0094] Accelerated development phase: Over N consecutive fixed monitoring periods, the overall compression rate If the values ​​show a continuous and obvious increasing trend, it can be determined that the land subsidence in the area is in an accelerated development stage.

[0095] Uniform growth phase: Over N consecutive fixed monitoring periods, the overall compression rate... If the magnitude of the increase or decrease in the value is always less than 10% and there is no significant change, then the ground subsidence can be determined to be in a stage of uniform development.

[0096] Deceleration stabilization phase: If, over N consecutive fixed monitoring periods, the overall compression rate... If the value shows a continuous decreasing trend, it can be determined that the ground subsidence is in a deceleration phase or gradually tending to a stable state.

[0097] The parameter N is set to have a value greater than or equal to 3 to ensure the reliability of the judgment.

[0098] S2. Under the synchronous time node of vertical detection, the horizontal coordinates of various underground points are collected synchronously to obtain the displacement data of each point in the horizontal direction. Based on the collected underground horizontal displacement data, a systematic comparative analysis is conducted to identify the spatial distribution characteristics of the displacement field, thereby determining the location of the underground settlement center in the coal mine goaf. By comparing the differences in the magnitude and direction of horizontal displacement between adjacent upper and lower underground points, the relative motion characteristics between layers are analyzed to determine whether there is significant shear deformation in the layer. Combining the comprehensive monitoring data of vertical settlement and horizontal displacement, a three-dimensional deformation monitoring system for underground space covering displacement, deformation and trend analysis is constructed to realize multi-dimensional dynamic monitoring and evaluation of the entire process of ground settlement in the goaf.

[0099] The determination of whether shear deformation exists in the layer segment is made by analyzing the relationship between the horizontal displacements of three points: point a, point b, and point c.

[0100] Calculate the relative horizontal displacement of segment ab:

[0101] Calculate the relative horizontal displacement of segment bc:

[0102] , and These are the horizontal displacement vectors of points a, b, and c during the current monitoring period t, respectively.

[0103] , and These are the horizontal displacement vectors of points a, b, and c at the current monitoring period t-1, respectively.

[0104] When the calculated relative horizontal displacement of segment ab or segment bc or If the value exceeds the preset displacement difference threshold, which is a value preset according to geological conditions and monitoring requirements, the system will determine that there is a significant shear deformation phenomenon in the corresponding ab or bc layer. This judgment is based on the degree of difference in the horizontal displacement vector between the upper and lower layers, thereby revealing the relative displacement of the strata in the horizontal direction.

[0105] In determining the location of the underground subsidence center in a coal mine goaf, the system makes a comprehensive judgment by analyzing the horizontal displacement vector directions at three points at different depths: point a, point b, and point c. This includes the following typical scenarios:

[0106] When the horizontal displacement vectors of points a, b, and c all point in the same direction, it indicates that the monitoring area is on the same side of the subsidence center, and the common direction of these displacement vectors can indicate the direction of the subsidence center, thus providing an important clue for locating the subsidence center.

[0107] When the horizontal displacement vectors of points a, b, and c exhibit a radial divergence pattern, meaning they radiate outward from a certain center point, the system determines that the monitored area is located in the boundary region of the settlement center, reflecting that the area is in the transition zone of settlement influence.

[0108] When the horizontal displacement vectors of points a, b, and c converge in a centripetal pattern, meaning they all point to the same center point, the system determines that the monitored area is located inside the settlement center, indicating that the area is directly affected by the traction of the settlement core.

[0109] By analyzing the horizontal displacement vector directions of multiple monitoring points, the specific range and precise location of the underground subsidence center can be gradually delineated in the horizontal space, thus forming a holistic understanding of the spatial distribution of the subsidence area.

[0110] S3. By collecting depth and horizontal displacement data from various underground points, the vertical settlement rate and horizontal displacement rate of each point are calculated. Based on the values ​​of the vertical settlement rate and horizontal displacement rate, the composite motion rate of each underground point is finally calculated. By comparing the composite motion rate with a preset deformation severity level threshold, the severity of the actual deformation motion of the underground points is determined, such as slight, moderate, or severe. On this basis, the spatial distribution of the composite motion rate of different underground points is analyzed. By identifying the area where the composite motion rate values ​​are highest and reach the severe level, the core area of ​​deformation impact is determined.

[0111] By calculating the vertical settlement rate and horizontal displacement rate of the collected underground points, the final composite motion rate of each underground point is calculated, which includes the following steps:

[0112] For each of the points a, b, and c defined from top to bottom, calculate its vertical settlement rate and horizontal displacement rate:

[0113] The vertical settlement rate is the rate of change of depth at each point over time. For point a, the calculation formula is as follows:

[0114]

[0115] Let be the vertical settlement rate at point a. and Inversely proportional;

[0116] This refers to the depth data of point a in the current monitoring period t;

[0117] The depth data for point a in the previous monitoring period t-1;

[0118] Vertical settlement rates at points b and c and The same calculation applies to the next step.

[0119] The horizontal displacement rate is the rate of change of the horizontal displacement vector at each point with time. For point a, the calculation formula is:

[0120]

[0121] Let a be the horizontal displacement rate at point a. and Inversely proportional;

[0122] Let a be the horizontal displacement vector of point a during the current monitoring period t;

[0123] Let a be the horizontal displacement vector of point a in the previous monitoring cycle t-1;

[0124] Horizontal displacement rates of point b and point c and The same calculation applies to the next step.

[0125] The formula for calculating the composite velocity of point a is:

[0126]

[0127] The combined velocity of point b and point c and Calculate in the same way for the remaining steps.

[0128] The determination of the intensity of actual deformation at underground points, analysis of the spatial distribution of the composite motion rate at different underground points, and identification of the core area affected by deformation are specifically carried out as follows:

[0129] When determining the degree of deformation severity, the system compares the calculated composite motion rate at each underground point with a pre-set threshold for the degree of deformation severity based on geological conditions and engineering requirements. Specifically:

[0130] When the synthetic motion rate When the system determines that the deformation at this point is slight, it indicates that the deformation activity at this point is relatively mild and has little impact on the surrounding environment.

[0131] When the rate of synthetic motion is at the lower limit threshold When the deformation at a certain point is within a certain range, the system determines that the deformation intensity at that point is moderate, indicating that the deformation activity at that point is at an acceptable but concerning level, which may have a certain impact on local stability.

[0132] When the synthetic motion rate Reaching or exceeding the upper limit threshold When the system determines that the deformation at this point is severe, it means that the deformation activity at this point is very active and there is a high risk of instability.

[0133] Among them, the lower limit threshold and upper limit threshold These are parameters pre-set based on the specific geological conditions, soil and rock mechanical properties, and engineering safety standards of the coal mine goaf. The value is always greater than This is to ensure the reasonableness of the threshold settings and the effectiveness of the grade determination.

[0134] The specific method for determining the core area affected by deformation is as follows: within each fixed monitoring cycle, the system comprehensively compares the composite motion rate of each underground point along the vertical line. This allows us to identify the areas where the deformation is most significant.

[0135] The system will synthesize motion rate The area where the highest values ​​are concentrated and have reached the level of severe deformation is identified as the core area of ​​deformation impact in the current monitoring period. This area represents the zone with the most concentrated deformation and the highest risk in the ground subsidence activity.

[0136] By comprehensively analyzing the spatial distribution and temporal trends of the core area over M consecutive monitoring periods, the system can determine the direction of expansion, transfer path, or convergence of the subsidence impact range, providing dynamic basis for long-term monitoring and early warning.

[0137] The value range of M is M≥2, which ensures the continuity of the analysis and the reliability of the trend judgment, and avoids misjudgment caused by fluctuations in single-cycle data.

[0138] S4. Using the time node of vertical detection synchronization as a fixed monitoring cycle, the synthetic motion rate of each underground point is systematically compared and analyzed. When the synthetic motion rate of a certain point exceeds the preset warning threshold and its trend shows a continuous increase over multiple consecutive monitoring cycles, it can be determined that the deformation activity in the area is intensifying, the foundation stability is gradually being lost, and there is a significant risk of instability. On this basis, the highway to which the area belongs is further designated as a high-risk area, and corresponding early warning signals are triggered based on the actual level of the synthetic motion rate.

[0139] When the synthetic motion rate reaches a preset warning threshold and its trend shows a continuous increase, the system determines that the surface deformation activity in the area is intensifying. The specific implementation process includes the following steps:

[0140] For each underground location, the system calculates its composite motion rate. This rate comprehensively reflects the overall movement of the point's vertical settlement and horizontal displacement;

[0141] When the composite motion rate at a certain point More than or equal to When this happens, it is determined that the movement status at that point has reached the warning level;

[0142] The system analyzes the movement trend of this location: the composite movement rate of this location over K consecutive fixed monitoring periods. If the value shows a continuous upward trend, it is determined that the trend of change is continuously increasing.

[0143] The specific method for designating the highway area as a high-risk zone and issuing an early warning is as follows: when the combined motion rate of at least J underground points within the monitoring area reaches the warning threshold. Furthermore, if the movement trend of these points shows a continuous increase, then the area is identified by the system as a high-risk zone;

[0144] The warning is issued based on the determination of high-risk areas, and the warning level is determined according to the maximum composite motion rate of points within the high-risk area:

[0145] When the maximum value of the combined motion rate of the points in the high-risk area is max( (less than the preset threshold) When a yellow alert is triggered, a yellow alert notification will be sent to the highway management unit, the local regulatory department and the emergency command center, along with detailed location data and trend analysis reports, and recommendations to strengthen daily patrols and on-site duty.

[0146] When the maximum value of the combined motion rate of the points in the high-risk area is max( The threshold is reached or exceeded. When a red alert is triggered, immediately advise and coordinate with traffic management departments to close the section of highway, establish a physical isolation zone, and prohibit all vehicles and personnel from passing through to prevent secondary disasters.

[0147] Where, max( ) represents the maximum value of the composite motion rate of each point in the high-risk zone, and the value of J must be at least 2, that is, at least two points must meet the conditions to trigger the high-risk zone determination, and the value of K must be greater than or equal to 2.

[0148] This embodiment also provides a coal mine goaf ground subsidence monitoring system. The monitoring system is used to execute the above-described monitoring method and includes the following functional modules:

[0149] The data acquisition module collects data from underground points along roads in coal mine goaf areas. The data from these underground points are values ​​at different depths along a vertical line. Initially, the underground points are divided at equal intervals. The module monitors and collects data on the vertical spacing of each point at fixed time intervals, completing the vertical detection of the underground points, calculating the compression rate of the strata in the vertical direction, analyzing and comparing the compression rates in the vertical direction at different times, and determining the stage of ground subsidence development.

[0150] The deformation analysis module synchronously collects the horizontal coordinates of underground points at the same time node as the vertical detection, and compares and analyzes the displacement data of the acquired horizontal coordinates to determine the location of the underground settlement center in the coal mine goaf. By comparing the horizontal coordinate displacement vector and direction between the upper and lower underground points, it determines whether there is shear deformation in the layer and constructs a three-dimensional deformation monitoring system for underground space.

[0151] The comprehensive evaluation module calculates the vertical settlement rate and horizontal displacement rate of the collected underground points, and finally calculates the composite motion rate of the underground points to determine the intensity of the actual deformation and movement of the underground points. It also analyzes the spatial distribution of the composite motion rate of different underground points to identify the core area affected by deformation.

[0152] The early warning response module uses the time node of vertical detection synchronization as a fixed monitoring cycle. By comparing and analyzing the synthetic motion rate of underground points, when the synthetic motion rate reaches the warning threshold and its trend shows a continuous increase, it is judged that the deformation of the area is intensifying, the stability is gradually being lost, and there is a risk of instability. The highway in this area is designated as a high-risk area and an early warning is issued.

[0153] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0154] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0155] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0156] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A method for monitoring ground subsidence in coal mine goaf areas, characterized in that, Includes the following steps: S1. Collect data on underground points along roads in coal mine goaf areas. The data on these underground points are values ​​at different depths along vertical lines. Initially, the underground points are divided at equal intervals. The vertical spacing of each point is monitored and data is collected at fixed time intervals. Vertical detection of the underground points is completed, and the compression rate of the strata in the vertical direction is calculated. The compression rates in the vertical direction at different times are analyzed and compared to determine the stage of ground subsidence development. S2. At the time node of vertical detection synchronization, the horizontal coordinates of underground points are collected synchronously, and the displacement data of the acquired horizontal coordinates are compared and analyzed to determine the location of the underground settlement center in the coal mine goaf. By comparing the horizontal coordinate displacement vector and direction between the upper and lower underground points, it is determined whether there is shear deformation on the vertical line, and a three-dimensional deformation monitoring system for underground space is constructed. S3. By calculating the vertical settlement rate and horizontal displacement rate of the collected underground points, the final composite motion rate of the underground points is calculated, the intensity of the actual deformation motion of the underground points is determined, the spatial distribution of the composite motion rate of different underground points is analyzed, and the core area of ​​deformation influence is determined. S4. Using the time node of vertical detection synchronization as a fixed monitoring cycle, by comparing and analyzing the synthetic motion rate of underground points, when the synthetic motion rate reaches the warning threshold and its trend shows a continuous increase, it is judged that the deformation on the vertical line is intensifying, the stability is gradually lost, and there is a risk of instability. The highway on the vertical line is designated as a high-risk area and an early warning is issued.

2. The method for monitoring ground subsidence in coal mine goaf according to claim 1, characterized in that: The different depth values ​​on the vertical line correspond to the data collected at three underground points, which are defined from top to bottom as point a, point b, and point c, where point a is closest to the surface and point c is the deepest. The compression rate of the strata in the vertical direction is calculated. The compression rate is the overall compression rate of the vertical profile formed by points a, b, and c. The formula for calculating the overall compression rate is: in , These are the depth data for points a and c at time t in the current monitoring period; , These are the depth data for points a and c at time t-1 of the previous monitoring period, respectively. The monitoring period is fixed in duration; For this vertical profile at a fixed monitoring cycle duration The overall compression rate within.

3. The method for monitoring ground subsidence in coal mine goaf according to claim 2, characterized in that: By analyzing the overall compression rate over N consecutive fixed monitoring periods Determine the development stage of land subsidence: Accelerated development phase: N consecutive fixed monitoring cycles If the value continues to increase, it is determined that the settlement is in an accelerated phase; Uniform development stage: N consecutive fixed monitoring cycles If the range of numerical increase or decrease is consistently less than 10%, then the settlement is determined to be in a uniform rate stage. Deceleration stabilization phase: N consecutive fixed monitoring cycles If the value continues to decrease, it is determined that the settlement is in a stage of deceleration or tending to stabilize.

4. The method for monitoring ground subsidence in coal mine goaf according to claim 2, characterized in that: The process for determining whether shear deformation exists on a vertical line includes: judging by analyzing the relationship between the horizontal displacements of points a, b, and c. Calculate the relative horizontal displacement of segment ab: Calculate the relative horizontal displacement of segment bc: , and These are the horizontal displacement vectors of points a, b, and c during the current monitoring period t, respectively. , and These are the horizontal displacement vectors of points a, b, and c at the current monitoring period t-1, respectively. when or If the displacement difference exceeds the preset threshold, it is determined that the corresponding ab or bc segment has significant shear deformation.

5. The method for monitoring ground subsidence in coal mine goaf according to claim 4, characterized in that: The process for determining the location of the underground subsidence center in a coal mine goaf includes: analyzing the horizontal displacement vector directions of three points: point a, point b, and point c. If the horizontal displacement vectors of points a, b, and c all point in the same direction, then points a, b, and c are located on the same side of the underground settlement center, and the common direction of the displacement vectors is the direction of the settlement center. If the horizontal displacement vectors of points a, b, and c diverge radially, then points a, b, and c are determined to be located in the boundary region of the settlement center. If the horizontal displacement vectors of points a, b, and c converge in a centripetal pattern, then points a, b, and c are located inside the settlement center.

6. The method for monitoring ground subsidence in coal mine goaf according to claim 2, characterized in that: By calculating the vertical settlement rate and horizontal displacement rate of the collected underground points, the final composite motion rate of each underground point is calculated, which includes the following steps: For each of the points a, b, and c defined from top to bottom, calculate the vertical settlement rate and horizontal displacement rate for each point: The vertical settlement rate is the rate of change of depth at each point over time. For point a, the calculation formula is as follows: Let be the vertical settlement rate at point a; This refers to the depth data of point a in the current monitoring period t; The depth data for point a in the previous monitoring period t-1; Vertical settlement rates at points b and c and The same calculation applies to the next step. The horizontal displacement rate is the rate of change of the horizontal displacement vector at each point with time. For point a, the calculation formula is: Let a be the horizontal displacement rate at point a; Let a be the horizontal displacement vector of point a during the current monitoring period t; Let a be the horizontal displacement vector of point a in the previous monitoring cycle t-1; Horizontal displacement rates of point b and point c and The same calculation applies to the next step. The formula for calculating the composite velocity of point a is: The combined velocity of point b and point c and Calculate in the same way for the remaining steps.

7. A method for monitoring ground subsidence in a coal mine goaf according to claim 6, characterized in that: The determination of the intensity of actual deformation at underground points, analysis of the spatial distribution of the composite motion rate at different underground points, and identification of the core area affected by deformation are specifically carried out as follows: Determine the severity of deformation: Compare the calculated composite motion rate at each underground location with a preset threshold for the severity of deformation. when < At that time, the degree of deformation was determined to be slight; when ≤ < At that time, the degree of deformation was determined to be moderate; when ≥ At that time, the degree of deformation was determined to be severe; in, and This is a preset threshold based on geological conditions and engineering requirements, and > .

8. A method for monitoring ground subsidence in a coal mine goaf according to claim 7, characterized in that: The specific method for determining the core area affected by deformation is as follows: within a single monitoring period, compare the combined motion rates of various underground points along the vertical line. ; Will The area where the points with the highest values ​​and those reaching the level of severe deformation are distributed is determined as the core area of ​​deformation impact in the current monitoring period; By analyzing the spatiotemporal distribution and evolution trend of the core area over M consecutive monitoring periods, the direction of expansion or transfer of the subsidence impact range can be determined. The value range of M is: M≥2.

9. A method for monitoring ground subsidence in a coal mine goaf according to claim 7, characterized in that: When the rate of synthetic motion reaches the warning threshold and its trend shows a continuous increase, it is determined that the deformation on the vertical line is intensifying. The specific steps include: For each underground point, calculate its composite motion rate. ; when ≥ When the synthetic motion rate reaches the warning threshold, it is determined that the rate of motion has reached the warning threshold. Analysis of trends: Within K consecutive fixed monitoring periods, when If the value continues to increase, it is determined that the trend of change is continuously increasing; The specific method for designating highways on vertical lines as high-risk zones and issuing warnings is as follows: when the combined motion rate of at least J underground points within the monitoring area reaches the warning threshold... If the trend of change shows a continuous increase, then the road on the vertical line is identified as a high-risk area; The warning is issued based on the determination of high-risk areas, and the warning level is determined according to the maximum composite motion rate of points within the high-risk area: When max( ) < A yellow alert will be issued at that time; When max( )≥ At that time, a red alert was issued; Where max( ) represents the maximum value of the composite motion velocity of the point, and the values ​​of J and K are both in the range of: J≥2, K≥2.

10. A ground subsidence monitoring system for coal mine goaf areas, characterized in that, The monitoring system is used to perform the monitoring method as described in any one of claims 1-9, and the monitoring system includes the following functional modules: The data acquisition module collects data from underground points along roads in coal mine goaf areas. The data from these underground points are values ​​at different depths along a vertical line. Initially, the underground points are divided at equal intervals. The module monitors and collects data on the vertical spacing of each point at fixed time intervals, completing the vertical detection of the underground points, calculating the compression rate of the strata in the vertical direction, analyzing and comparing the compression rates in the vertical direction at different times, and determining the stage of ground subsidence development. The deformation analysis module synchronously collects the horizontal coordinates of underground points at the same time node as the vertical detection, and compares and analyzes the displacement data of the acquired horizontal coordinates to determine the location of the underground settlement center in the coal mine goaf. By comparing the horizontal coordinate displacement vectors and directions between the upper and lower underground points, it determines whether there is shear deformation on the vertical line and constructs a three-dimensional deformation monitoring system for underground space. The comprehensive evaluation module calculates the vertical settlement rate and horizontal displacement rate of the collected underground points, and finally calculates the composite motion rate of the underground points to determine the intensity of the actual deformation and movement of the underground points. It also analyzes the spatial distribution of the composite motion rate of different underground points to identify the core area affected by deformation. The early warning response module uses the time node of vertical detection synchronization as a fixed monitoring cycle. By comparing and analyzing the synthetic motion rate of underground points, when the synthetic motion rate reaches the warning threshold and its trend shows a continuous increase, it is judged that the deformation on the vertical line is intensifying, the stability is gradually being lost, and there is a risk of instability. The highway on the vertical line is designated as a high-risk area and an early warning is issued.

Images