Microseismic Monitoring Method for Coal Mine Tunneling

Abstract

The present invention discloses a microseismic monitoring method for coal mine tunneling, which relates to the technical field of microseismic monitoring. By analyzing the rock mass characteristics and void characteristics in the propagation path multiple times and continuously optimizing and correcting the arrival time of the monitoring points, a convergent three-dimensional coordinate of the seismic source and the vibration time are obtained and output, so that the obtained seismic source is closest to the true seismic source, effectively improving the accuracy of seismic source monitoring. By determining whether to start the wave velocity seismic source to update the rock mass wave velocity based on the interval duration of the rock mass state and wave velocity update, the rock mass wave velocity is scientifically analyzed and reasonably updated, which helps to improve the accuracy and timeliness of earthquake prediction, and can avoid unscientifically updating the rock mass wave velocity to increase the risk of coal mine tunneling work.

Description

Technical Field

[0001] The present invention relates to the technical field of microseismic monitoring, and particularly to a microseismic monitoring method for coal mine tunneling. Background Art

[0002] When a rock mass ruptures under the action of external forces or internal factors, tiny seismic waves, i.e., microseismic signals, will be generated; microseismic monitoring receives microseismic signals through microseismic detectors arranged in the mine rock mass and obtains relevant parameters through signal processing and analysis, and uses these parameters to evaluate the stability of the mine rock mass; the mine microseismic monitoring technology has been used as a relatively mature technical means and applied to the monitoring and evaluation of the stability of each mine rock mass;

[0003] Currently, microseismic monitoring uses the time difference analysis method to infer the propagation path and direction of microseismic signals. However, in the actual coal mine tunneling process, the non-uniformity of rocks and the multi-scale fractures existing in the rocks will cause changes in the propagation speed of microseismic signals, resulting in the inability to accurately infer the propagation path and direction; at the same time, microseismic monitoring uses a fixed update duration to monitor and update the wave velocity of the rock mass, which is likely to start the seismic source for wave velocity monitoring and update when the rock mass state is inappropriate (such as problems of unstable rock mass or fractures), and lack of scientific analysis and reasonable setting is likely to lead to further rock mass damage or sliding. Summary of the Invention

[0004] Based on this, it is necessary to provide a microseismic monitoring method for coal mine tunneling in view of the problems mentioned in the above background art.

[0005] The purpose of the present invention can be achieved through the following technical solutions: The microseismic monitoring method for coal mine tunneling includes the following steps:

[0006] S1: Establish a monitoring grid by dividing the coal mine tunneling area into several monitoring regions, and several detectors are installed in each monitoring region to collect microseismic information; the microseismic information includes the arrival time, amplitude, and frequency of the monitoring point.

[0007] S2: When at least four pieces of microseismic information are collected, the monitoring points where the microseismic information is collected are recorded as target monitoring points, and the microseismic information of the target monitoring points is obtained to construct a seismic source location equation Use the Gaussian elimination method to solve the system of equations to solve the three-dimensional coordinates (X0 1 , Y0 1 , Z0 1 ) of the primary seismic source and the primary vibration time t0 1 , where v represents the wave velocity of the rock mass;

[0008] S3: Use laser scanning technology to generate a three-dimensional model, and connect the position of the primary seismic source and the target monitoring points to obtain several primary propagation paths;

[0009] S4: Analyze the rock mass characteristics and void characteristics of each primary propagation path to obtain the rock mass characteristic parameters and void characteristic parameters, and comprehensively analyze the two to obtain the time optimization parameter; optimize the microseismic information according to the time optimization parameter to obtain the three-dimensional coordinates of the secondary seismic source and the secondary vibration time;

[0010] S5: Repeat S3 - S4 until the obtained three-dimensional coordinates of the seismic source and the vibration time converge, and output the converged three-dimensional coordinates of the seismic source and the vibration time as the final accurate three-dimensional coordinates of the seismic source and the vibration time;

[0011] S6: Analyze the rock mass state to obtain the overall rock mass state value, and guide the coal mine tunneling work accordingly;

[0012] S7: Determine whether to activate the wave velocity seismic source to update the rock mass wave velocity by the interval duration of the rock mass state and wave velocity update.

[0013] In some embodiments, comprehensively analyze the rock mass characteristic parameters and void characteristic parameters to obtain the time optimization parameter, and optimize the microseismic information according to the time optimization parameter to obtain the three-dimensional coordinates of the secondary seismic source and the secondary vibration time; the specific steps are as follows:

[0014] Extract the rock mass characteristic parameters and void characteristic parameters, where the rock mass characteristic parameters include the density index and the rock mass interface index, and the void characteristic parameters include the void interface index and the void attenuation index;

[0015] Substitute the density index DZ, the rock mass interface index FZ, the void interface index Hθ, and the void attenuation index Hδ into the set formula Calculate to obtain the time optimization parameter T1, where β1 and β2 are respectively the set correction factors; substitute the time optimization parameter T1 into the secondary seismic source location equation system Use the Gaussian elimination method to solve the equation system to solve the three-dimensional coordinates of the secondary seismic source (X0 2 、Y0 2 、Z0 2 ) and the secondary vibration time t0 2 .

[0016] In some embodiments, the specific steps to obtain the rock mass characteristic parameters by analyzing the rock mass characteristics of each primary propagation path are as follows:

[0017] 301: Identify the propagation paths in the three-dimensional model to obtain several voids, independent blocks, and the point cloud density of the independent blocks;

[0018] 302: Set that there are i independent blocks in each propagation path, calculate the volume of the independent blocks and denote it as Dni; compare and analyze the point cloud density of the independent blocks with the set density interval to generate high-density independent blocks, medium-density independent blocks and low-density independent blocks; respectively count the numbers of high-density independent blocks, medium-density independent blocks and low-density independent blocks, and denote them as F1, F2 and F3 respectively;

[0019] 303: Respectively sum up the point cloud densities of the high-density independent blocks, medium-density independent blocks and low-density independent blocks to obtain the high-density sum value, medium-density sum value and low-density sum value, and denote them as F4, F5 and F6 respectively;

[0020] Substitute F1, F2, F3, F4, F5 and F6 into the set formula Calculate to obtain the density index DZ, where f1, f2 and f3 are respectively the set correction factors;

[0021] 304: Arrange the independent blocks according to the propagation path, calculate the difference in the point cloud density of adjacent independent blocks to obtain the density difference; compare and analyze the density difference with the set difference interval to generate strong interfaces, medium interfaces and weak interfaces, and denote them as F7, F8 and F9 respectively; substitute F7, F8 and F9 into the set formula FZ = f4×F7 + f5×F8 + f6×F9 to calculate to obtain the rock mass interface index FZ, where f4, f5 and f6 are respectively the set correction factors, and f4 > f5 > f6.

[0022] In some embodiments, the specific steps for obtaining the void characteristic parameters by analyzing the void characteristics of each primary propagation path are as follows:

[0023] 401: Set that there are j voids in each propagation path, arrange the voids in sequence according to the propagation path to construct a void distribution map;

[0024] 402: Calculate the distance between two adjacent voids and denote it as the void spacing; compare and analyze the void spacing with the set spacing interval to generate a compact void distribution, a balanced and compact void distribution and a loose void distribution; respectively count the numbers of the compact void distribution, the balanced and compact void distribution and the loose void distribution, and denote them as H1, H2 and H3;

[0025] 403: Extract the void volumes of adjacent voids respectively recorded as compact void distribution, balanced compact void distribution, and loose void distribution, and calculate their means to obtain the mean compact volume, balanced mean, and mean loose volume. And so on to obtain the mean compact volume, balanced mean, and mean loose volume of all voids recorded as compact void distribution, balanced compact void distribution, and loose void distribution. Then sum up all the mean compact volume, balanced mean, and mean loose volume respectively to obtain the compactness index denoted as δ1, the balance index denoted as δ2, and the looseness index denoted as δ3; Substitute δ1, δ2, and δ3 into the set formula for calculation to obtain the void attenuation index Hδ, where α1, α2, and α3 are respectively the set correction factors;

[0026] 404: Extract the number of voids j, then there are (2×j) void interfaces, and substitute them together with the number of times H1 of compact void distribution, the number of times H2 of balanced compact void distribution, and the number of times H3 of loose void distribution into the set formula for calculation to obtain the void interface index Hθ, where α4 is the set correction coefficient.

[0027] In some embodiments, analyze the rock mass state to obtain the overall rock mass state value, and guide the coal mine tunneling work accordingly; The specific steps are as follows:

[0028] Arbitrarily select a monitoring area, calculate the distance between the monitoring area and the seismic source according to the three-dimensional coordinates of the seismic source, and denote it as the influence distance G1;

[0029] Extract the vertical coordinate of the seismic source to obtain the seismic source depth and denote it as G2; Extract the amplitude and frequency, and denote them as G3 and G4 respectively; Substitute G1, G2, G3, and G4 into the set formula for calculation to obtain the rock mass state value GZ, where g1, g2, g3, and g4 are respectively the set correction factors; And so on to obtain the rock mass state value of each monitoring area, and calculate the mean of the rock mass state values to obtain the overall rock mass state value;

[0030] When the overall rock mass state value is less than the set state threshold, generate a prompt to suspend the tunneling work and display it.

[0031] In some embodiments, determine whether to turn on the wave velocity seismic source to update the rock mass wave velocity by the interval duration of the rock mass state and wave velocity update; The specific steps are as follows:

[0032] Extract the previous wave velocity update time, calculate the time difference between the update time and the current time to obtain the update interval duration, and denote it as G5;

[0033] Substitute the update interval duration G5 and the overall rock mass state value into the set formula Calculate to obtain the updated value QZ, where z1 and z2 are respectively set correction factors; when the updated value is greater than the set update threshold, start the acoustic wave source to obtain the rock mass wave velocity in the monitoring area.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1. By analyzing the rock mass characteristics and void characteristics in the propagation path multiple times and continuously optimizing and correcting the arrival time of the monitoring points to obtain the convergent three-dimensional coordinates and vibration time of the source and output them, the obtained source is closest to the true source, effectively improving the accuracy of source monitoring;

[0036] 2. By using the interval duration of the rock mass state and wave velocity update to determine whether to start the wave velocity source to update the rock mass wave velocity, scientifically analyze and reasonably update the rock mass wave velocity, which helps to improve the accuracy and timeliness of earthquake prediction, and can avoid unscientific updating of the rock mass wave velocity to increase the risk of coal mine tunneling work. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0038] Figure 1 It is a schematic diagram of the method steps of the present invention;

[0039] Figure 2 It is a schematic flow diagram of the present invention

[0040] Figure 3 It is a schematic diagram of establishing a monitoring grid of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the following will make a detailed description of the specific embodiments of the present invention with reference to the drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein. Those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0042] As Figure 1-2 shown, a microseismic monitoring method for coal mine tunneling includes the following steps:

[0043] S1: As Figure 3As shown in the figure, a monitoring grid is established: a preset range of the coal mine heading area is divided into n areas, where n is a positive integer; each area includes a number of monitoring points, and geophones are set at the monitoring points to collect microseismic information; it is set that each area corresponds to a collection sub-station, and the collection sub-stations correspond to the monitoring areas one by one; at the same time, a number of wave velocity seismic sources are installed in each monitoring area to monitor and calculate the wave velocity of the rock mass; the microseismic information includes: vibration arrival time, frequency and amplitude;

[0044] S2: When at least four pieces of microseismic information are collected, the monitoring points where the microseismic information is collected are recorded as target monitoring points, and the microseismic information of the target monitoring points is obtained to construct a seismic source location equation Use the Gaussian elimination method to solve the system of equations to solve the three-dimensional coordinates of the primary seismic source (X0 1 , Y0 1 , Z0 1 ) and the primary vibration time t0 1 ; where v represents the wave velocity of the rock mass, t1, t2... tn are the arrival times of the corresponding monitors, and (X1, Y1, Z1), (X2, Y2, Z2)... (Xn, Yn, Zn) are the three-dimensional coordinates of the corresponding monitors; by using the seismic source location equation to solve to obtain the position of the primary seismic source, due to the influence of the rock mass characteristics, the three-dimensional coordinates of the primary seismic source are not very accurate and there is a certain error; the rock mass characteristics refer to the non-uniformity of the rock mass and the change in the microseismic propagation velocity caused by voids;

[0045] S3: Use laser scanning technology to scan each monitoring area to obtain a large amount of discrete point cloud data, process and reconstruct the point cloud data to generate a three-dimensional model; by relying on the three-dimensional coordinates of the primary seismic source (X0 1 , Y0 1 , Z0 1 ) mark the position of the primary seismic source in the three-dimensional model, and connect the position of the primary seismic source and the target monitoring points to obtain a number of primary propagation paths, and the primary propagation paths correspond to the monitoring points one by one, and each detection point corresponds to a primary propagation path;

[0046] S4: Identify the propagation paths in the three-dimensional model to obtain several voids, independent blocks, and the point cloud density of the independent blocks. It should be noted that an independent block refers to a discrete area composed of a group of adjacent points, and there is an obvious boundary between this area and the surrounding point cloud. Such independent blocks represent different rock strata, ore bodies, or other objects in the internal structure of the coal mine. The existence of independent blocks leads to the existence of interfaces. The more independent blocks there are, the more interfaces increase and affect the wave propagation speed, making it slower. When there are multiple independent rock blocks in the rock mass, interfaces will form between these different rock blocks. At the same time, voids usually have a lower acoustic wave propagation speed. When the wave passes through the void area, its propagation speed will slow down. This is because the gas or fluid existing in the void will block the propagation of the acoustic wave, thus affecting the propagation speed. By analyzing the rock mass characteristics and void characteristics of each primary propagation path to obtain the rock mass characteristic parameters and void characteristic parameters, and comprehensively analyzing the two to obtain the time optimization parameter, and optimizing the microseismic information according to the time optimization parameter to obtain the three-dimensional coordinates (X0 2 、Y0 2 、Z0 2 ) of the secondary seismic source and the vibration time t0 2 of the primary seismic source; specifically:

[0047] S41: Assume that there are i independent blocks in each propagation path, calculate the volume of the independent block and denote it as Dni, where i = 1, 2, 3... m2, and m2 is a positive integer representing the total number of independent blocks in the propagation path. Here, n represents the number of the propagation path, and i represents the number of the independent block;

[0048] Compare and analyze the point cloud density of the independent block with the set density interval. When the point cloud density is greater than the maximum value in the set density interval, it indicates that the independent block has a relatively large density, and the wave propagation speed in this independent block is relatively large. Then, mark this independent block as a high-density independent block. When the point cloud density is within the set density interval, mark this independent block as a medium-density independent block. When the point cloud density is less than the minimum value in the set density interval, mark this independent block as a low-density independent block. Count the numbers of high-density independent blocks, medium-density independent blocks, and low-density independent blocks respectively, and denote them as F1, F2, and F3;

[0049] Sum up the point cloud densities of the high-density independent block, medium-density independent block, and low-density independent block respectively to obtain the high-density sum value, medium-density sum value, and low-density sum value, and denote them as F4, F5, and F6 respectively. Use the set formula to calculate to obtain the density index DZ, where f1, f2, and f3 are the set correction factors respectively. By analogy, the density index of each propagation path can be obtained;

[0050] S42: Arrange the independent blocks according to the propagation path, calculate the difference in the point cloud density of adjacent independent blocks to obtain the density difference; compare and analyze the density difference with the set difference interval. When the density difference is greater than the maximum value in the set difference interval, it indicates that there is a large difference in density between two adjacent independent blocks, and there is also a large difference in the rock mass density between the corresponding independent blocks, which is recorded as a strong interface; when the density difference is within the set difference interval, it is recorded as a medium interface; when the density difference is less than the minimum value in the set difference interval, it is recorded as a weak interface; count the numbers of strong interfaces, medium interfaces, and weak interfaces respectively, and record them as F7, F8, and F9 respectively; calculate using the set formula FZ = f4×F7 + f5×F8 + f6×F9 to obtain the rock mass interface index FZ, where f4, f5, and f6 are set correction factors respectively, and f4 > f5 > f6; record the density index DZ and the rock mass interface index FZ as rock mass characteristic parameters;

[0051] S43: Assume there are j voids in each propagation path, calculate the void volume and record it as Knj, where j = 1, 2, 3... m3, m3 takes positive integer values, m3 represents the total number of voids in the propagation path, n represents the propagation path number, and j represents the void number;

[0052] Arrange the voids in sequence according to the propagation path to construct a void distribution map, calculate the distance between two adjacent voids and record it as the void spacing; compare and analyze the void spacing with the set spacing interval. When the void spacing is greater than the maximum value in the set spacing interval, it indicates that there is a large spacing between two adjacent voids, and the adjacent two spacings are loosely distributed, and record a void compact distribution; when the void spacing is within the set spacing interval, record a void balanced and compact distribution; when the void spacing is less than the minimum value in the set spacing interval, record a void loose distribution; count the numbers of void compact distributions, void balanced and compact distributions, and void loose distributions respectively, and record them as H1, H2, and H3 respectively;

[0053] S44: Extract the void volumes of adjacent voids recorded as void compact distributions, void balanced and compact distributions, and void loose distributions respectively, and calculate their mean values to obtain the compact volume mean, balanced mean, and loose volume mean. By analogy, obtain the compact volume means, balanced means, and loose volume means of all void compact distributions, void balanced and compact distributions, and void loose distributions, and then sum up all the compact volume means, balanced means, and loose volume means respectively to obtain the compactness index recorded as δ1, the balance index recorded as δ2, and the looseness index recorded as δ3; calculate using the set formula to obtain the void attenuation index Hδ, where α1, α2, and α3 are set correction factors respectively;

[0054] S45: Extract the number of voids j. Then there are (2×j) void interfaces. Use the set formula to calculate to obtain the void interface index Hθ, where α4 is the set correction coefficient; Denote the void interface index Hθ and the void attenuation index Hδ as void characteristic parameters;

[0055] S46: Use the set formula to calculate to obtain the time optimization parameter T1, where β1 and β2 are the set correction factors respectively; Substitute the time optimization parameter T1 into the secondary seismic source location equations Use the Gaussian elimination method to solve the equations to solve for the three-dimensional coordinates of the secondary seismic source (X0 2 , Y0 2 , Z0 2 ) and the secondary vibration time t0 2 ; By analyzing the rock mass characteristics and void characteristics existing between the primary seismic source and the monitoring point to obtain the time optimization parameter T1, and optimizing the arrival time of the monitoring point through the time optimization parameter T1 to obtain the three-dimensional coordinates of the secondary seismic source and the vibration time, which are more accurate than the three-dimensional coordinates of the primary seismic source and the secondary vibration time;

[0056] S5: Repeat S3 - S4 until the obtained three-dimensional coordinates of the seismic source and the vibration time converge, and output the converged three-dimensional coordinates of the seismic source and the vibration time as the final accurate three-dimensional coordinates of the seismic source and the vibration time; The steps to judge convergence are as follows: When the time optimization is repeated m4 times, then the time optimization parameter at this time is Tm4, and the obtained are the three-dimensional coordinates of the (m4 + 1)-th seismic source and the (m4 + 1)-th vibration time; Calculate the distance between the m4-th three-dimensional coordinates of the seismic source and the (m4 + 1)-th three-dimensional coordinates of the seismic source using the Euclidean distance formula to obtain the m4-th seismic source spacing, and calculate the time difference between the (m4 + 1)-th vibration time and the m4-th vibration time to obtain the m4-th time difference; When the m4-th seismic source spacing is less than the preset seismic source spacing and the m4-th time difference is less than the set time difference, it means that the m4-th optimization result is convergent, and the three-dimensional coordinates of the (m4 + 1)-th seismic source and the (m4 + 1)-th vibration time are the closest to the true seismic source at this time; Through multiple analyses of the rock mass characteristics and void characteristics in the propagation path and continuous optimization and correction, the convergent three-dimensional coordinates of the seismic source and the vibration time are obtained and output, so that the obtained seismic source is closest to the true seismic source, effectively improving the accuracy of seismic source monitoring;

[0057] S6: Arbitrarily select a monitoring area, calculate the distance between the monitoring area and the seismic source according to the three-dimensional coordinates of the seismic source, and denote it as the influence distance G1; Extract the vertical coordinate of the seismic source and obtain the seismic source depth and denote it as G2; Extract the amplitude and frequency, and denote them as G3 and G4 respectively; Use the set formula The rock mass state value GZ is calculated, where g1, g2, g3, and g4 are respectively set correction factors; and so on to obtain the rock mass state values of each monitoring area, and the mean value of the rock mass state values is calculated to obtain the overall rock mass state value denoted as When the overall rock mass state value is greater than or equal to the set state threshold, it indicates that the overall rock mass state is normal at this time, and the coal mine tunneling work can operate normally; when the overall rock mass state value is less than the set state threshold, it indicates that the overall rock mass state is not good at this time, and there are greater risks in carrying out the tunneling work, then a prompt to suspend the tunneling work is generated and displayed;

[0058] S7: Extract the previous wave velocity update time, calculate the time difference between the update time and the current time to obtain the update interval duration, and denote it as G5; use the set formula Calculate to obtain the update value QZ, where z1 and z2 are respectively set correction factors; when the update value is greater than the set update threshold, start the acoustic wave source to obtain the rock mass wave velocity of the monitoring area; by judging whether to start the wave velocity source to update the rock mass wave velocity based on the interval duration of the rock mass state and wave velocity update, scientifically analyzing and reasonably updating the rock mass wave velocity helps to improve the accuracy and timeliness of earthquake prediction, and can avoid unscientifically updating the rock mass wave velocity to increase the risks of coal mine tunneling work.

[0059] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0060] The above-described embodiments only express several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A microseismic monitoring method for coal mine tunneling, characterized in that, it includes the following steps: S1: Establish a monitoring grid. By dividing the coal mine tunneling area into several monitoring areas, several monitoring points are set in each monitoring area, and each is equipped with a geophone for collecting microseismic information; S2: When at least four pieces of microseismic information are collected, the monitoring points where the microseismic information is collected are recorded as target monitoring points, and the microseismic information of the target monitoring points is obtained to construct a source location equation; The Gaussian elimination method is used to solve the system of equations to solve the three-dimensional coordinates of the primary source and the time when the primary source vibrates; S3: Use laser scanning technology to generate a three-dimensional model, and connect the primary source position and the target monitoring points to obtain several primary propagation paths; S4: Analyze the rock mass characteristics and void characteristics of each primary propagation path to obtain rock mass characteristic parameters and void characteristic parameters, and comprehensively analyze the two to obtain time optimization parameters; Optimize the microseismic information according to the time optimization parameters to obtain the three-dimensional coordinates of the secondary source and the secondary vibration time; S5: Repeat S3 - S4 until the obtained source three-dimensional coordinates and vibration time converge, and output the converged source three-dimensional coordinates and vibration time as the final accurate source three-dimensional coordinates and vibration time; S6: Analyze the rock mass state to obtain the overall rock mass state value, and use this to guide the coal mine tunneling work; S7: Determine whether to start the wave velocity source to update the rock mass wave velocity by updating the rock mass state and the wave velocity update interval duration; Comprehensively analyze the rock mass characteristic parameters and void characteristic parameters to obtain time optimization parameters, and optimize the microseismic information according to the time optimization parameters to obtain the three-dimensional coordinates of the secondary source and the secondary vibration time; The specific steps are as follows: Extract the rock mass characteristic parameters and void characteristic parameters, where the rock mass characteristic parameters include the density index and the rock mass interface index, and the void characteristic parameters include the void interface index and the void attenuation index; Formulate and calculate the density index, rock mass interface index, void interface index, and void attenuation index to obtain the time optimization parameter T1; substitute the time optimization parameter T1 into the secondary seismic source location equations Use Gaussian elimination to solve the equations to obtain the three-dimensional coordinates of the secondary seismic source and the time when the secondary seismic source vibrates; The specific steps to obtain the rock mass characteristic parameters by analyzing the rock mass characteristics of each primary propagation path are as follows: 301: Identify the propagation paths in the three-dimensional model to obtain several voids, independent blocks, and the point cloud density of the independent blocks; 302: Assume that there are i independent blocks in each propagation path, calculate the volume of the independent blocks and record it as Dni; Compare and analyze the point cloud density of the independent blocks with the set density interval to generate high-density independent blocks, medium-density independent blocks, and low-density independent blocks; Count the number of high-density independent blocks, medium-density independent blocks, and low-density independent blocks respectively; 303: Calculate the sum of the point cloud densities of the high-density independent blocks, medium-density independent blocks, and low-density independent blocks respectively to obtain the high-density sum value, medium-density sum value, and low-density sum value, and normalize the three with the number of high-density independent blocks, medium-density independent blocks, and low-density independent blocks to obtain the density index; 304: Arrange the independent blocks according to the propagation path, calculate the difference in the point cloud density of adjacent independent blocks to obtain the density difference; Compare and analyze the density difference with the set difference interval to generate strong interfaces, medium interfaces, and weak interfaces; Count the number of strong interfaces, medium interfaces, and weak interfaces respectively, and perform numerical calculations on the three to obtain the rock mass interface index; The specific steps to obtain the void characteristic parameters by analyzing the void characteristics of each primary propagation path are as follows: 401: Set that there are j voids in each propagation path, and arrange the voids in sequence according to the propagation path to construct a void distribution map; 402: Calculate the distance between two adjacent voids and record it as the void spacing; Compare and analyze the void spacing with the set spacing interval to generate void compact distribution, void balanced compact distribution, and void loose distribution; Count the number of times of void compact distribution, void balanced compact distribution, and void loose distribution respectively; 403: Extract the void volumes of adjacent voids recorded as void compact distribution, void balanced compact distribution, and void loose distribution respectively, and calculate their mean values to obtain the compact volume mean, balanced mean, and loose volume mean. By analogy, obtain the compact volume mean, balanced mean, and loose volume mean of all voids recorded as void compact distribution, void balanced compact distribution, and void loose distribution. Then, sum up all the compact volume mean, balanced mean, and loose volume mean respectively to obtain the compact index, balanced index, and loose index, and perform numerical calculation and analysis on the three to obtain the void attenuation index; 404: Extract the number of voids j. Then, there are twice the number of void interfaces as the number of voids. Perform numerical calculation and analysis on it with the number of times of void compact distribution, void balanced compact distribution, and void loose distribution to obtain the void interface index.

2. The microseismic monitoring method for coal mine tunneling according to claim 1, characterized in that, obtain the overall rock mass state value by analyzing the rock mass state, and guide the coal mine tunneling work accordingly; The specific steps are as follows: Arbitrarily select a monitoring area, calculate the distance between the monitoring area and the seismic source based on the three-dimensional coordinates of the seismic source, and record it as the influence distance; Extract the vertical coordinate of the seismic source to obtain the seismic source depth, and extract the amplitude and frequency; Perform numerical calculation and analysis on the seismic source depth, amplitude, frequency, and influence distance to obtain the rock mass state value; By analogy, obtain the rock mass state value of each monitoring area, and calculate the mean value of the rock mass state values to obtain the overall rock mass state value; When the overall rock mass state value is less than the set state threshold, generate a prompt to suspend the tunneling work and display it.

3. The microseismic monitoring method for coal mine tunneling according to claim 1, characterized in that, judge whether to turn on the wave velocity seismic source to update the rock mass wave velocity by taking the interval duration of the rock mass state and wave velocity update; The specific steps are as follows: Extract the previous wave velocity update time, and calculate the time difference between the update time and the current time to obtain the update interval duration; Perform comprehensive analysis on the update interval duration and the overall rock mass state value to obtain an update value; When the update value is greater than the set update threshold, start the acoustic wave seismic source to obtain the rock mass wave velocity of the monitoring area.

Images