A mine pressure monitoring device for coal mine roadways and an early warning and prediction analysis method

Abstract

The present invention discloses a mine pressure monitoring device and an early warning and prediction analysis method for coal mine roadways. The device includes a signal converter, a bolt sensor or a cable bolt sensor, and a surrounding rock displacement sensor. The bolt sensor or the cable bolt sensor is used to collect the force data of the mine roadway, the surrounding rock displacement sensor is used to collect the displacement data of the mine roadway, and the signal converter is used to receive the force data and the displacement data and synchronously send them to the host computer in a predetermined format. The method includes: extracting the characteristic values of the sensor monitoring data; according to the characteristic values of the monitoring data of each sensor, performing a collaborative analysis on the monitoring data of the force and displacement of the roadway surrounding rock to obtain a comprehensive analysis result. The present invention comprehensively considers and analyzes the indicators in two dimensions of force and displacement during the mine pressure monitoring process of the roadway, reduces the analysis error of the mine pressure of the roadway, and designs a comprehensive analysis algorithm, laying a foundation for the intelligent development of the mine pressure of the roadway.

Description

Technical Field

[0001] The present invention relates to the technical field of roadway abutment pressure monitoring, and particularly to a coal mine roadway abutment pressure monitoring device and an early warning and prediction analysis method. Background Art

[0002] At present, the roadway abutment pressure monitoring mainly includes two aspects: force and displacement. The stress condition of the surrounding rock is monitored by bolt or cable extensometers. By monitoring the stress of bolts and cables, two aspects of information can be reflected: the stress change of bolt and cable support bodies; the change of roadway surrounding rock pressure. The displacement of the surrounding rock is mainly monitored by a surrounding rock displacement measuring instrument. By the change amount of different base point displacements in the borehole, the displacement change of the roadway surrounding rock is reflected. The displacement change includes two parts: the separation amount of the roof and the displacement amount of the two sides.

[0003] During the change process of the roadway surrounding rock, there are both force changes and displacement changes, and force and displacement accompany each other and are interrelated. However, currently, in the process of collecting the two parameters of the surrounding rock stress and displacement, different monitoring devices are used for data collection, artificially separating the two indicators reflecting the rock stratum information and monitoring them separately, resulting in large errors in the actual application process.

[0004] In the process of roadway abutment pressure data analysis, two indicators of force and displacement are required to analyze and evaluate the monitoring data respectively. However, this analysis method artificially separates the two-dimensional information of the surrounding rock, and the analysis results often cannot truly reflect the on-site situation or false alarms occur. Summary of the Invention

[0005] Aiming at the above problems, the purpose of the present invention is to provide a coal mine roadway abutment pressure monitoring device and an early warning and prediction analysis method, develop a signal converter capable of simultaneously collecting the stress and displacement of the roadway surrounding rock, and design a corresponding early warning analysis algorithm, comprehensively considering and analyzing the two-dimensional indicators of force and displacement in the process of roadway abutment pressure monitoring, so as to reduce the analysis error of roadway abutment pressure.

[0006] To solve the above technical problems, the embodiments of the present invention provide the following solutions:

[0007] On the one hand, a coal mine roadway abutment pressure monitoring device is provided, including a signal converter, a bolt sensor or a cable sensor, and a surrounding rock displacement sensor. The bolt sensor or the cable sensor is connected to the signal converter, the surrounding rock displacement sensor is connected to the signal converter, and the signal converter is connected to a host computer;

[0008] The bolt sensor or the cable bolt sensor is used to collect the stress data of the roadway mine, the surrounding rock displacement sensor is used to collect the displacement data of the roadway mine, the signal converter is used to receive the stress data and the displacement data, and synchronously send them to the host computer in a predetermined format. The host computer stores the data received in the predetermined format in the same database list.

[0009] Preferably, the predetermined format is: Time+MG data+MS data+WYYD data, where Time is the data acquisition time, MG data is the stress data collected by the bolt sensor, MS data is the stress data collected by the cable bolt sensor, and WYYD data is the displacement data collected by the surrounding rock displacement sensor.

[0010] Preferably, an early warning index system is set in the host computer, including:

[0011] Early warning index of bolt sensor: 80% of the bolt yield strength;

[0012] Early warning index of cable bolt sensor: 80% of the cable bolt breaking strength;

[0013] Early warning index of the stress state of the butterfly-shaped surrounding rock stress;

[0014] Early warning index of the surrounding rock displacement sensor: 80% of the elongation rate of the bolt or the cable bolt;

[0015] Taking the breaking value under the fatigue damage of the bolt or the cable bolt as the early warning index of the support body under the alternating load;

[0016] Early warning index of unqualified pre-tightening force of the bolt or the cable bolt;

[0017] Prediction and forecast of the advanced abutment pressure range of the bolt or the cable bolt.

[0018] Preferably, the analysis process of the host computer for the monitoring data includes:

[0019] Analysis of the stress of the roadway surrounding rock:

[0020] Judge whether the stress data exceeds the early warning value. If it exceeds the early warning value, an early warning message is sent, and it is judged whether it is a false alarm of the sensor. If it is not a false alarm of the sensor, analyze the stress state of the bolt or the cable bolt, including: whether the stress of the bolt or the cable bolt increases or decreases, whether the pre-tightening force of the bolt or the cable bolt is qualified, whether the surrounding rock has an overall displacement, whether there is an alternating load, and whether the bolt or the cable bolt bears the advanced abutment pressure; through analyzing the curve characteristics of each early warning index, draw a sub-analysis conclusion; if it is a false alarm of the sensor, obtain the false alarm type according to the curve characteristics, including mutation, equipment short circuit, exceeding the threshold, and give a corresponding sensor maintenance early warning;

[0021] If the stress data does not exceed the warning value, perform a conventional stress parameter analysis of the bolt or cable, including the distance between the equipment and the working face, the data change rate of the bolt or cable, the average stress and standard deviation of the bolt or cable within a cycle, generate a conventional analysis conclusion, and give the conventional analysis conclusion and safety evaluation of the equipment installation position;

[0022] Analysis of roadway surrounding rock displacement, including shallow displacement analysis and deep displacement analysis of the roadway:

[0023] Judge whether the displacement data exceeds the warning value. If it exceeds the warning value, send a warning message and judge whether it is a sensor false alarm. If it is not a sensor false alarm, analyze the shallow displacement graph and deep displacement graph of the roadway to obtain the shallow displacement change rate and shallow displacement amount, as well as the deep displacement change rate and deep displacement amount. Calculate the surrounding rock separation amount based on the shallow displacement amount and deep displacement amount, and then obtain the surrounding rock movement analysis conclusion; if it is a sensor false alarm, obtain the false alarm type according to the curve characteristics, including mutation, equipment short circuit, reverse of deep or shallow base points, and give the corresponding sensor maintenance warning;

[0024] If the displacement data does not exceed the warning value, perform a conventional analysis of surrounding rock movement data, including the distance between the equipment and the working face, the setting of the monitoring equipment base point, and the analysis of the extreme value and average value of the separation within a cycle, generate a conventional analysis conclusion, and give the conventional analysis conclusion and safety evaluation of the equipment installation position;

[0025] After that, conduct a collaborative analysis of the stress and displacement of the roadway surrounding rock, give an overall analysis conclusion, and provide corresponding control strategies.

[0026] On the one hand, provide a warning and prediction analysis method based on the above-mentioned mine pressure monitoring equipment for coal mine roadways, including the following steps:

[0027] S1. Extract the characteristic values of the sensor monitoring data, including: secant slope K, average value of the monitoring data Standard deviation σ of the monitoring data and data change rate Δ of the monitoring data;

[0028] S2. Analyze the stress condition of the roadway surrounding rock according to the characteristic values of the monitoring data of the bolt sensor or cable sensor;

[0029] S3. Analyze the displacement condition of the roadway surrounding rock according to the characteristic values of the monitoring data of the surrounding rock displacement sensor;

[0030] S4. Conduct a fault diagnosis on the sensor according to the characteristic values of the monitoring data;

[0031] S5. Conduct a conventional monitoring data analysis on the sensor;

[0032] S6. Coordinately analyze the monitoring data of the stress on the surrounding rock of the roadway and the monitoring data of the displacement of the surrounding rock of the roadway. Four indicators are derived from the two dimensions of stress and displacement: bolt stress, cable stress, deep displacement, and shallow displacement. Use a radar chart to display the mutual relationship of the four indicators and obtain a comprehensive analysis result.

[0033] Preferably, in step S1, the secant slope K refers to the slope of the straight line formed by connecting any point on the monitoring curve and the initial data point within the analysis period. The calculation formula for the secant slope K is:

[0034]

[0035] The maximum secant slope K max is:

[0036] K max = max{|tanα i |}, i ∈ (1, n)

[0037] The average secant slope is:

[0038]

[0039] The average value of the monitoring data The calculation formula is:

[0040]

[0041] Where: m is the amount of measured data within the analysis period, m = n + 1; P ti is the monitoring data at each moment;

[0042] The calculation formula for the standard deviation σ of the monitoring data is:

[0043]

[0044] The calculation formula for the change rate Δ of the monitoring data is:

[0045]

[0046] Preferably, step S2 includes:

[0047] S201. Judge whether the monitoring data curve of the bolt sensor or the cable sensor has an increasing or rising trend, and 4 conditions need to be met:

[0048] Ⅰ. The data change rate Δ > 5%;

[0049] Ⅱ. The maximum secant slope K max > 0.2;

[0050] Ⅲ. The absolute value of the average secant slope

[0051] Ⅳ. Among them, the yield strength of the bolt is 80%, and the breaking strength of the cable bolt is 80%.

[0052] S202. To judge whether the bolt or the cable bolt reaches the warning value, 2 conditions need to be met:

[0053] Ⅰ.

[0054] Ⅱ. The data change rate Δ>3%.

[0055] S203. To judge whether the monitoring data curve has a decreasing or downward trend, 3 conditions need to be met:

[0056] Ⅰ. The data change rate Δ>5%.

[0057] Ⅱ. The average secant slope

[0058] Ⅲ.

[0059] S204. To judge whether the monitoring data curve is under the action of alternating load, 3 conditions need to be met:

[0060] Ⅰ. The data change rate Δ>5%.

[0061] Ⅱ. The average secant slope

[0062] Ⅲ.

[0063] S205. To judge whether the monitoring data curve first rises and then falls, 3 conditions need to be met:

[0064] Ⅰ. The maximum secant slope K max ≥0;

[0065] Ⅱ. The average secant slope

[0066] Ⅲ.

[0067] S206. To judge whether the roadway's bearing of the advanced abutment pressure in the working face rises, 5 conditions need to be met:

[0068] Ⅰ. The maximum secant slope K max ≥0.05;

[0069] Ⅱ. When K≥0.5K max the corresponding time T 0.5 is the starting point of the influence of the advanced abutment pressure; K max the corresponding time point T maxis the peak point affected by the advanced abutment pressure;

[0070] Ⅲ. At time T max the distance D from the coal mining face to the monitoring equipment, i.e., the sensor max satisfies: 0 ≤ D max ≤ 150 m;

[0071] Ⅳ. T 0.5 ≠ T max ;

[0072] Ⅴ. When it is impossible to verify whether the curve is rising from Ⅰ to Ⅳ, the computer is assisted manually to judge and a judgment program is added;

[0073] S207. Judge whether the initial pre-tightening force of the bolt or cable bolt is qualified and analyze the construction quality, which needs to meet 4 conditions:

[0074] Ⅰ. Calculate the average value of all monitoring data within 10 days after the initial installation of the bolt or cable bolt, denoted as P mg10 or P ms10 and use it as an index for evaluating the construction quality analysis of the bolt or cable bolt;

[0075] Ⅱ. Take 30 - 60% of the yield strength of the bolt or cable bolt as the qualified index of the pre-tightening force, denoted as P MG or P MS ;

[0076] Ⅲ. The qualified index P of the bolt pre-tightening force mg10 ≥ P MG or 20 kN, it is judged as qualified, otherwise, it is judged as unqualified;

[0077] Ⅳ. The qualified index P of the cable bolt pre-tightening force ms10 ≥ P MS or 60 kN, it is judged as qualified, otherwise, it is judged as unqualified.

[0078] Preferably, step S3 includes:

[0079] S301. The classification warning index for the displacement change of the roadway surrounding rock: yellow warning and red warning;

[0080] Ⅰ. L max = min{bolt length × elongation rate, cable bolt length × elongation rate};

[0081] L 预警值 = min{bolt length × elongation rate × 80%, cable bolt length × elongation rate × 80%};

[0082] L 弹 = min{elongation amount in the elastic deformation stage of the bolt, elongation amount in the elastic deformation stage of the cable bolt}, and this value is determined by experiments;

[0083] Ⅱ. Yellow warning: L 深max or L 浅max >L 弹 ;

[0084] Ⅲ. Red warning: L 深max or L 浅max >L 预警值 ;

[0085] S302. Only the shallow surrounding rock emits warning information, satisfying 3 conditions:

[0086] Ⅰ. L 深max =L 浅max ≥L 预警值 ;

[0087] Ⅱ. Data change rate Δ > 5%;

[0088] S303. Only the deep surrounding rock emits warning information, satisfying 3 conditions:

[0089] Ⅰ. L 深max ≥L 预警值 ;

[0090] Ⅱ. L 深max >L 浅max =0;

[0091] Ⅲ. Data change rate Δ > 5%;

[0092] S304. Displacements occur in both the deep and shallow parts of the surrounding rock, and warning information is emitted, satisfying 2 conditions:

[0093] Ⅰ. L 深max >L 浅max ≥L 预警值 ;

[0094] Ⅱ. Data change rate Δ > 5%;

[0095] S305. The displacements in both the deep and shallow parts of the surrounding rock increase rapidly but do not reach the warning value, satisfying 3 conditions:

[0096] Ⅰ. L 深max ≥L 浅max >0;

[0097] Ⅱ. L 深max <L 预警值 ;

[0098] Ⅲ. Maximum secant slope K max >0.2;

[0099] Ⅳ. Absolute value of average secant slope

[0100] Ⅴ. The data change rate Δ > 5%;

[0101] S306. When the surrounding rock displacement monitoring data is small and fluctuates, it meets two conditions:

[0102] Ⅰ. L 深max <1 and L 浅max <1;

[0103] Ⅱ.

[0104] Preferably, step S4 includes:

[0105] S401. The data change rate Δ = 0 or NaN%, indicating that there is a fault in the monitoring sensor and it cannot transmit data normally;

[0106] S402. Determine whether there are jump values in the monitoring data curve: meet three conditions:

[0107] Ⅰ. The maximum secant slope |K max | > 3;

[0108] Ⅱ.

[0109] Ⅲ. The data change rate Δ < 20%;

[0110] S403. There are principle errors in the use of the surrounding rock displacement sensor:

[0111] Ⅰ. L 深max <L 浅max ;

[0112] Step S5 includes:

[0113] S501. The general analysis conclusion of the surrounding rock displacement sensor: the installation position of the sensor, the depth of the deep base point, the depth of the shallow base point, the maximum value, minimum value, and average value of the deep base point data shown by the monitoring data, and the maximum value, minimum value, and average value of the shallow base point data.

[0114] S502. The general analysis conclusion of the bolt sensor or cable anchor sensor: the installation position of the sensor, the initial pre-tightening force, the stable stress condition of the bolt or cable anchor, the distance between the working face and the sensor, the data change rate within the analysis period, and the pressure change condition of the bolt or cable anchor.

[0115] Preferably, step S6 includes:

[0116] S601. Data normalization:

[0117] Ⅰ. Normalize the monitoring data of the bolt sensor to the interval [0, 1]:

[0118]

[0119]

[0120]

[0121] Ⅱ. Normalize the monitoring data of the anchor cable sensor to the interval [0, 1]:

[0122]

[0123]

[0124]

[0125] Ⅲ. Normalize the deep displacement data to the interval [0, 1]:

[0126]

[0127] Minimum passing value = 0;

[0128]

[0129] Ⅳ. Normalize the shallow displacement data to the interval [0, 1]:

[0130]

[0131] Minimum passing value = 0;

[0132]

[0133] S602. Create a standard data radar chart:

[0134] Normalize the monitoring data of the four indicators, and divide them into the following three cases according to the passing value and warning value, and display them using a radar chart;

[0135]

[0136] S603. Real-time data comprehensive evaluation index:

[0137] On the basis of data normalization, calculate the relevant indicators: the total area S of the radar chart max , the area S0 enclosed by the initial installation passing value, the area S 预警值 enclosed by the warning value;

[0138] The calculation method is as follows:

[0139] Ⅰ. The total area S enclosed by the normalized data radar chart max :

[0140] S max = 2

[0141] Ⅱ. Area S0 enclosed by the initial installation qualified values of the normalized data radar chart:

[0142]

[0143] Ⅲ. Area S enclosed by the warning values of the normalized data radar chart 预警值 :

[0144] S 预警值 = S Ⅰ预警值 + S Ⅱ预警值 + S Ⅲ预警值 + S Ⅳ预警值

[0145] Where:

[0146]

[0147]

[0148]

[0149]

[0150] Ⅳ. Area S enclosed by the normalized real-time monitoring data radar chart:

[0151] S = S Ⅰ + S Ⅱ + S Ⅲ + S Ⅳ

[0152] Where:

[0153]

[0154]

[0155]

[0156]

[0157] Ⅴ. Analysis results of comprehensive evaluation indicators:

[0158] When 0 < S < S0, it indicates that the real-time monitoring data is lower than the qualified value, and the support failure or unqualified support quality should be considered;

[0159] When S0 < S i < S i预警值 , it indicates that the real-time monitoring data is within a reasonable range;

[0160] When S i > S i预警值 , When dealing with potential risks, it should be based on the actual situation.

[0161] When S > S max it indicates that the support has failed and there is an extreme risk of instability in the surrounding rock of the roadway, and measures must be taken to deal with it.

[0162] The beneficial effects brought by the technical solution provided in the embodiment of the present invention at least include:

[0163] In the embodiment of the present invention, the received force data and displacement data are synchronously sent to the upper computer for data processing through a signal converter according to a predetermined format, and the curve characteristics are analyzed by using the slope of the data secant line. The indexes of the two dimensions of force and displacement in the process of roadway abutment pressure monitoring are comprehensively considered and analyzed, reducing the analysis error of roadway abutment pressure. And a comprehensive analysis algorithm is designed. This analysis algorithm can not only analyze real-time data, but also analyze the time-varying characteristics of the monitoring data, facilitating the computer to autonomously identify and analyze and put forward reasonable support suggestions, laying a foundation for the intelligent development of coal mine roadway abutment pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0164] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0165] Figure 1 is a schematic structural diagram of the coal mine roadway abutment pressure monitoring device provided by the embodiment of the present invention;

[0166] Figures 2a - 2d is a schematic diagram of the analysis process of the monitoring data provided by the embodiment of the present invention;

[0167] Figure 3 is a schematic diagram of the secant line slope of the curve provided by the embodiment of the present invention;

[0168] Figure 4 is a schematic diagram of the correlation between the secant line slope and the monitoring data provided by the embodiment of the present invention;

[0169] Figure 5 is a radar chart of the relationship between the force and displacement of the surrounding rock of the roadway provided by the embodiment of the present invention;

[0170] Figures 6 - 86 is a radar chart of the relationship between the force and displacement of the surrounding rock of the roadway in 81 cases provided by the embodiment of the present invention.

[0171] As shown in the figure, in order to clearly show the structure of the embodiments of the present invention, specific structures and devices are marked in the figure. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device, and environment. According to specific needs, those of ordinary skill in the art can adjust or modify these devices and environments, and such adjustments or modifications are still within the protection scope of the present invention. Detailed implementation manners

[0172] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0173] The embodiments of the present invention first provide a coal mine roadway ground pressure monitoring device, as Figure 1 shown. The coal mine roadway ground pressure monitoring device includes a signal converter, a bolt sensor or a cable bolt sensor, and a surrounding rock displacement sensor. The bolt sensor or the cable bolt sensor is connected to the signal converter, the surrounding rock displacement sensor is connected to the signal converter, and the signal converter is connected to a host computer.

[0174] Among them, the bolt sensor or the cable bolt sensor is used to collect the force data of the roadway ground pressure, the surrounding rock displacement sensor is used to collect the displacement data of the roadway ground pressure, the signal converter is used to receive the force data and the displacement data, and synchronously send them to the host computer in a predetermined format. The host computer stores the data received in a predetermined format in the same database list.

[0175] Further, the predetermined format is: Time + MG data + MS data + WYYD data, where Time is the data acquisition time, MG data is the force data collected by the bolt sensor, MS data is the force data collected by the cable bolt sensor, and WYYD data is the displacement data collected by the surrounding rock displacement sensor.

[0176] Further, an early warning index system is set in the host computer, including:

[0177] Early warning index of bolt sensor: 80% of the bolt yield strength;

[0178] Early warning index of cable bolt sensor: 80% of the cable bolt breaking strength;

[0179] Early warning index of the stress state of the butterfly-shaped surrounding rock stress;

[0180] Early warning index of surrounding rock displacement sensor: 80% of the elongation rate of bolts or cable bolts;

[0181] Taking the breaking value of bolts or cable bolts under fatigue damage as the early warning index of the support body under alternating load;

[0182] Early warning index for unqualified pre-tightening force of bolts or cable bolts;

[0183] Prediction and forecast of the advanced abutment pressure range of bolts or cable bolts.

[0184] In the embodiment of the present invention, the analysis process of the upper computer for the monitoring data is as Figures 2a - 2d shown (due to space limitations, Figure 2a , Figure 2b , Figure 2c and Figure 2d together constitute a complete flow chart), including:

[0185] Analysis of the stress of roadway surrounding rock:

[0186] Judge whether the stress data exceeds the early warning value. If it exceeds the early warning value, an early warning message is sent, and it is judged whether it is a false alarm of the sensor. If it is not a false alarm of the sensor, analyze the stress state of the bolts or cable bolts, including: whether the stress of the bolts or cable bolts increases or decreases, whether the pre-tightening force of the bolts or cable bolts is qualified, whether the surrounding rock has a whole displacement, whether there is an alternating load, and whether the bolts or cable bolts bear the advanced abutment pressure; through analyzing the curve characteristics of each early warning index, draw a sub-analysis conclusion; if it is a false alarm of the sensor, according to the curve characteristics, obtain the false alarm type, including mutation, equipment short circuit, exceeding the threshold, and give a corresponding sensor maintenance early warning;

[0187] If the stress data does not exceed the early warning value, conduct a conventional stress parameter analysis of the bolts or cable bolts, including the distance between the equipment and the working face, the data change rate of the bolts or cable bolts, the average stress and standard deviation of the bolts or cable bolts within a cycle, generate a conventional analysis conclusion, and give a conventional analysis conclusion and safety evaluation of the equipment installation position;

[0188] Analysis of roadway surrounding rock displacement, including shallow displacement analysis and deep displacement analysis of the roadway:

[0189] Judge whether the displacement data exceeds the early warning value. If it exceeds the early warning value, an early warning message is sent, and it is judged whether it is a false alarm of the sensor. If it is not a false alarm of the sensor, analyze the shallow displacement graph and deep displacement graph of the roadway, obtain the shallow displacement change rate and shallow displacement amount, as well as the deep displacement change rate and deep displacement amount, obtain the surrounding rock separation amount according to the shallow displacement amount and deep displacement amount, and then draw a surrounding rock movement analysis conclusion; if it is a false alarm of the sensor, according to the curve characteristics, obtain the false alarm type, including mutation, equipment short circuit, reverse of the deep or shallow base point, and give a corresponding sensor maintenance early warning;

[0190] If the displacement data does not exceed the warning value, routine analysis of surrounding rock movement data is carried out, including the distance between the equipment and the working face, the setting of the monitoring equipment base point, the analysis of the extreme value and the average value of the separation layer within the cycle, generating a routine analysis conclusion, giving the routine analysis conclusion of the equipment installation position and the safety evaluation;

[0191] After that, the collaborative analysis of the stress and displacement of the roadway surrounding rock is carried out, giving the overall analysis conclusion and providing the corresponding control strategy.

[0192] Furthermore, an early warning and prediction analysis method based on the above-mentioned mine pressure monitoring equipment for coal mine roadways provided by an embodiment of the present invention includes the following steps:

[0193] S1. Extract the characteristic values of the sensor monitoring data, including: the secant slope K, the average value of the monitoring data the standard deviation σ of the monitoring data and the change rate Δ of the monitoring data.

[0194] The basis for analyzing the law of mine pressure in the roadway is to analyze and obtain the key data in the monitoring data curve. The specific calculation is as follows:

[0195] (1) The secant slope K refers to the slope of the straight line formed by connecting any point on the monitoring curve with the initial data point within the analysis period, as shown by the dotted line in Figure 3 . The calculation formula for the secant slope K is:

[0196]

[0197] The maximum value of the secant slope K max is:

[0198] K max =max{|tanα i |}, i ∈ (1, n)

[0199] The average value of the secant slope is:

[0200]

[0201] Calculate the secant slope of all points on the curve to obtain the secant slope set {K}. The secant slope reflects the speed of the growth trend of the curve. Compare the secant slope curve with the original curve, as shown in Figure 4 . It can be seen from the data comparison that the secant slope is closely correlated with the original monitoring curve and can truly reflect the change law of the monitoring data.

[0202] (2) The average value of the monitoring data The calculation formula is:

[0203]

[0204] Where: m is the amount of measured data within the analysis period, m = n + 1; P ti is the monitoring data at each moment.

[0205] (3) The calculation formula for the standard deviation σ of the monitoring data is:

[0206]

[0207] (4) The calculation formula for the change rate Δ of the monitoring data is:

[0208]

[0209] S2. Analyze the stress condition of the surrounding rock of the roadway according to the characteristic values of the monitoring data of the bolt sensor or the cable bolt sensor; including:

[0210] S201. Judge whether the monitoring data curve of the bolt sensor or the cable bolt sensor has an increasing or rising trend, and 4 conditions need to be met:

[0211] Ⅰ. The data change rate Δ > 5%;

[0212] Ⅱ. The maximum secant slope K max > 0.2;

[0213] Ⅲ. The absolute value of the average secant slope

[0214] Ⅳ. where 80% of the bolt yield strength and 80% of the cable bolt breaking strength.

[0215] Law of roadway abutment pressure: The surrounding rock pressure at the location of the sensor does not exceed the warning value, but there is an increasing trend in the confining pressure. In the later stage, pay close attention to the change state of the bolt / cable bolt pressure, and promptly go down the well to implement the underground safety hazards. If the pressure shows abnormal changes or alarms, take corresponding treatment measures in a timely manner.

[0216] S202. Judge whether the bolt or the cable bolt reaches the warning value, and 2 conditions need to be met:

[0217] Ⅰ.

[0218] Ⅱ. The data change rate Δ > 3%.

[0219] Law of roadway abutment pressure: The surrounding rock pressure at the location of the sensor exceeds the warning value. After excluding the reasons for false alarms of the equipment, there is a risk of breakage of the bolt / cable bolt at this location, and the surrounding rock is on the verge of instability. Reinforcement measures need to be taken promptly at this location, and the number of operating personnel should be strictly controlled.

[0220] S203. Judge whether the monitoring data curve has a decreasing or falling trend, and 3 conditions need to be met:

[0221] Ⅰ. The data change rate Δ > 5%;

[0222] Ⅱ. Average secant slope

[0223] Ⅲ.

[0224] Roadway abutment pressure law: The data of this sensor shows that the surrounding rock pressure gradually decreases. There are three reasons for this situation: 1. The three diameters (drill hole diameter, support material diameter, and anchoring agent diameter) do not match, and the anchoring end is unstable; 2. The rock layer within the anchoring section of the bolt or cable bolt undergoes overall displacement, and the roadway surrounding rock loses its support effectiveness, and it is necessary to take measures such as additional bolting or passive support; 3. The three diameters match properly, but the rock layer in the anchoring section is soft, and the anchoring head is pulled loose. The historical curve will show the characteristic of stepwise decline. If this situation is confirmed on-site at this location, the mining party should promptly modify the support method to ensure the stability of the anchoring point.

[0225] S204. To determine whether the monitoring data curve is subjected to alternating loads, three conditions need to be met:

[0226] Ⅰ. The data change rate Δ > 5%;

[0227] Ⅱ. Average secant slope

[0228] Ⅲ.

[0229] Roadway abutment pressure law: The bolt / cable bolt sensor of this roadway shows that the surrounding rock is subjected to alternating loads, which will cause the bolt / cable bolt to fracture and fail far below its breaking strength. There are mainly two reasons for this situation: 1. Equipment short-circuit fault; 2. Duplicate equipment coding; 3. Influence of mining; 4. Influence of rock dynamic disasters. The specific reasons should be determined by the mining party in combination with the production situation and the geological conditions of the equipment location. When implementing the failure risk, corresponding measures should be taken in a timely manner, such as overhauling the monitoring equipment line or taking pressure relief measures to release the energy accumulated in the surrounding rock.

[0230] S205. To determine whether the monitoring data curve has a situation of first rising and then falling, three conditions need to be met:

[0231] Ⅰ. The maximum secant slope K max ≥0;

[0232] Ⅱ. Average secant slope

[0233] Ⅲ.

[0234] Roadway abutment pressure law: There are mainly three reasons for the situation where the monitoring curve first rises and then falls: 1. During the mining process, the peak value of the advanced abutment pressure generally appears within the range of 10 - 20m in front of the working face. After the working face has passed a certain position, the stress curve of the bolt / cable will change from rising to falling; 2. The anchoring agent at the anchoring end is not firmly bonded to the surrounding rock, losing the anchoring effect. The bolt / cable anchoring fails but does not break. At this time, the stress curve of the surrounding rock shows a step-down trend, and the surrounding rock is in a stage of gradually losing stability. 3. After the bolt / cable monitoring equipment is withdrawn, the wireless module is not turned off in time, resulting in continuous data transmission. At this time, the curve shows a cliff-like drop. Therefore, the wireless communication module should be turned off in time after the equipment is withdrawn.

[0235] S206. To determine whether the roadway is under the influence of the advanced abutment pressure of the working face and whether it is rising, 5 conditions need to be met:

[0236] Ⅰ. The maximum secant slope K max ≥0.05;

[0237] Ⅱ. When K≥0.5K max the corresponding time T 0.5 is the starting point of the influence of the advanced abutment pressure; K max the corresponding time point T max is the peak point of the influence of the advanced abutment pressure;

[0238] Ⅲ. At time T max the distance D max from the coal mining working face to the monitoring equipment, i.e., the sensor, satisfies: 0≤D max ≤150m;

[0239] Ⅳ. T 0.5 ≠T max ;

[0240] Ⅴ. When conditions Ⅰ→Ⅳ cannot verify whether the curve is rising, manual assistance and computer judgment are used, and a judgment program is added.

[0241] Roadway abutment pressure law: Starting from T 0.5 the stress of the support body begins to increase significantly, and it starts to be affected by the advanced abutment pressure. At this time, the distance D 0.5 from the equipment to the working face. The peak value of the abutment pressure appears at T max at this time, the distance D max from the equipment to the working face. It shows that the action range of the advanced abutment pressure is in front of the working face from D 0.5 to D max .

[0242] S207. To determine whether the initial pre-tightening force of the bolt or cable is qualified and analyze the construction quality, 4 conditions need to be met:

[0243] Ⅰ. Calculate the average value of all monitoring data within 10 days after the initial installation of the bolt or cable anchor, denoted as P mg10 or P ms10 , and use it as an index for analyzing the construction quality of the bolt or cable anchor;

[0244] Ⅱ. Take 30 - 60% of the yield strength of the bolt or cable anchor as the qualified index of the pre-tightening force, denoted as P MG or P MS ;

[0245] Ⅲ. For the bolt, if the qualified index of the pre-tightening force P mg10 ≥P MG or 20kN, it is judged as qualified; otherwise, it is judged as unqualified;

[0246] Ⅳ. For the cable anchor, if the qualified index of the pre-tightening force P ms10 ≥P MS or 60kN, it is judged as qualified; otherwise, it is judged as unqualified.

[0247] Law of roadway abutment pressure: Statistically analyze the qualified rate of the pre-tightening force when the bolts and cable anchors are initially installed, and count the unqualified areas. Evaluate the unqualified areas as potential risk areas, and it is recommended that the mine management handle the potential risk areas, take measures to appropriately supplement the pre-tightening force, give full play to the role of the support materials, and strengthen the quality control of the pre-tightening force construction.

[0248] S3. Analyze the displacement of the roadway surrounding rock based on the characteristic values of the monitoring data of the surrounding rock displacement sensors; including:

[0249] S301. Early warning indicators for the classification of the change in the displacement of the roadway surrounding rock: yellow early warning and red early warning;

[0250] Ⅰ. L max =min{bolt length × elongation rate, cable anchor length × elongation rate};

[0251] L 预警值 =min{bolt length × elongation rate × 80%, cable anchor length × elongation rate × 80%};

[0252] L 弹 =min{elongation amount in the elastic deformation stage of the bolt, elongation amount in the elastic deformation stage of the cable anchor}, and this value is determined by tests;

[0253] Ⅱ. Yellow early warning: L 深max or L 浅max >L 弹 ;

[0254] Ⅲ. Red early warning: L 深max or L 浅max >L 预警值 。

[0255] S302. Only the shallow surrounding rock emits early warning information, meeting three conditions:

[0256] Ⅰ. L 深max = L 浅max ≥ L 预警值 ;

[0257] Ⅱ. The data change rate Δ > 5%.

[0258] Roadway abutment pressure law: The monitoring data of the surrounding rock at the deep or shallow base points all exceed the alarm value, indicating that the separation amount of the surrounding rock at this position is relatively large. The bolt support is on the verge of failure. However, because the separation occurs in the shallow part, the cable bolt still has a supporting effect, and the overall failure risk is high. It is recommended that the mine take the method of adding cable bolts to strengthen the support.

[0259] S303. Only the deep surrounding rock emits early warning information, meeting three conditions:

[0260] Ⅰ. L 深max ≥ L 预警值 ;

[0261] Ⅱ. L 深max > L 浅max = 0;

[0262] Ⅲ. The data change rate Δ > 5%.

[0263] Roadway abutment pressure law: The monitoring data of the deep base points all exceed the alarm value, and the deep monitoring data is greater than the shallow monitoring data, indicating that the separation of the surrounding rock at this position occurs in the deep part. The rock strata within the bolt anchorage range undergo overall displacement, and the weight of all rock strata within the separation range is borne by the cable bolts. The risk of cable bolt failure is relatively high. At this time, the active support method has lost its effect. It is recommended that the mine take passive support methods such as setting up sheds or adding point columns to handle potential risks.

[0264] S304. Displacements occur in both the deep and shallow parts of the surrounding rock, and early warning information is emitted, meeting two conditions:

[0265] Ⅰ. L 深max > L 浅max ≥ L 预警值 ;

[0266] Ⅱ. The data change rate Δ > 5%.

[0267] Roadway abutment pressure law: Displacements occur in both the deep and shallow parts of the surrounding rock, and both exceed the set early warning value, indicating that the roadway surrounding rock at this position is relatively broken, and the surrounding rock shows a phenomenon of zonal deterioration. The risks of bolt and cable bolt failure are extremely high. It is recommended that the mine take measures such as grouting reinforcement, full-length anchorage cable bolt strengthening, and setting up sheds or adding point columns to coordinate and handle the danger.

[0268] S305. There is an accelerating increase in displacements in both the deep and shallow parts of the surrounding rock, but the warning value is not reached, meeting three conditions:

[0269] Ⅰ. L 深max ≥L 浅max >0;

[0270] Ⅱ. L 深max <L 预警值 ;

[0271] Ⅲ. The maximum secant slope K max >0.2;

[0272] Ⅳ. The absolute value of the average secant slope

[0273] Ⅴ. The data change rate Δ>5%.

[0274] The law of roadway abutment pressure: Displacements occur in both the deep and shallow parts of the surrounding rock, and neither exceeds the set warning value. The bolt and cable jointly play a supporting role. However, the monitoring data rises rapidly in the short term, and the risk increases. The change of the monitoring data at this position should be closely noted in a timely manner. When risks occur, treatment measures should be taken in a timely manner.

[0275] S306. When the monitoring data of the surrounding rock displacement is small and fluctuating, two conditions are met:

[0276] Ⅰ. L 深max <1 and L 浅max <1;

[0277] Ⅱ.

[0278] The law of roadway abutment pressure: The separation amounts of both the deep and shallow base points are less than 1 mm. The separation amount at this position is too small and the growth rate is not large. The resolution of the potentiometer of the surrounding rock movement sensor (0.1 mm) is relatively high. The length of the steel wire rope of the monitoring equipment is about 2 - 10 m. Subtle vibrations of the surrounding rock will cause changes in the potentiometer. Therefore, when the monitoring data is less than 1 mm, the monitoring data at this position can be ignored.

[0279] S4. Conduct fault diagnosis on the sensor according to the characteristic values of the monitoring data; including:

[0280] S401. The data change rate Δ = 0 or NaN%, indicating that there is a fault in the monitoring sensor and it cannot transmit data normally. It is recommended that the mine party handle it in a timely manner to ensure the stability and coherence of the monitoring data.

[0281] S402. Judge whether there are jump values in the monitoring data curve: Meeting three conditions:

[0282] Ⅰ. The maximum secant slope |K max |>3;

[0283] Ⅱ.

[0284] Ⅲ. The data change rate Δ < 20%.

[0285] It indicates that there are jump values during the monitoring process of the monitoring equipment. The reasons for the jump values are as follows: 1. There is a short - circuit fault in the line; 2. During the sensor coding process, there is duplicate coding. When the system determines the jump - value state, the analysis process will automatically eliminate the abnormal values, record the abnormal positions, and prompt the mine party to handle them in a timely manner.

[0286] S403. There is a principle error in the use of the surrounding - rock displacement sensor:

[0287] Ⅰ.L 深max <L 浅max 。

[0288] It indicates that when the data of the deep - base point is less than that of the shallow - base point, it shows that the designed use principle of the surrounding - rock monitoring equipment does not match. The most likely reasons for this situation are as follows: 1. During the installation process, the deep and shallow anchoring base points are reversed artificially; 2. The monitoring equipment is not tightened during the installation process; 3. The fixed base point of the equipment is loose during the monitoring process; 4. The steel wire rope is loose or broken; 5. If the monitoring data fluctuates around 1 mm, it is caused by the sensitivity of the potentiometer and the mechanical error of the separation - layer instrument. It is recommended that the mine party go down the well to actually check. After eliminating the equipment failure, tighten the steel wire rope of the equipment and then re - fix it or install a new monitoring equipment.

[0289] S5. Conduct routine monitoring data analysis on the sensors, including:

[0290] S501. Routine analysis conclusions of the surrounding - rock displacement sensor: the installation position of the sensor, the depth of the deep - base point, the depth of the shallow - base point, the maximum value, minimum value, and average value of the deep - base point data shown by the monitoring data, the maximum value, minimum value, and average value of the shallow - base point data;

[0291] S502. Routine analysis conclusions of the bolt sensor or cable - bolt sensor: the installation position of the sensor, the initial pre - tightening force, the stable stress condition of the bolt or cable - bolt, the distance between the working face and the sensor, the data change rate within the analysis period, and the pressure change situation of the bolt or cable - bolt.

[0292] For example: Routine analysis conclusions of the surrounding - rock displacement sensor: # The separation - layer sensor is installed at _ m from the cutting face, the depth of the deep - base point is _ m, the depth of the shallow - base point is _ m. The monitoring data shows that the maximum value of the deep - base point data is _ mm, the minimum value is _ mm, and the average value is _ mm; the maximum value of the shallow - base point data is _ mm, the minimum value is _ mm, and the average value is _ mm.

[0293] Routine analysis conclusions of the bolt / cable - bolt sensor: _ # The equipment is installed at _ m from the cutting face, the initial pre - tightening force is _ kN, anchorbolt / cable The force is relatively stable and basically in the ± kN, Month Day (when the working face advances _m, the working face is _m away from the equipment), the data change rate during the analysis period is ％ , bolt / cable The pressure changes greatly, and the pressure change situation should be closely monitored. bolt / cable The pressure change situation.

[0294] S6. Conduct collaborative analysis on the monitoring data of the stress of the roadway surrounding rock and the monitoring data of the displacement of the roadway surrounding rock. Four indicators are derived from the two dimensions of stress and displacement: bolt stress, cable stress, deep displacement, and shallow displacement. Use a radar chart to show the mutual relationship of the four indicators and obtain the comprehensive analysis result.

[0295] The above four indicators affect and interact with each other, and are intertwined with each other like quantum entanglement. To clearly express the entanglement relationship between the two dimensions and the four indicators, use a radar chart to clearly show the relationship between the data, as Figure 5 shown. The construction quality of the roadway and the safety state of the roadway where the monitoring equipment is located can be clearly shown in the radar chart.

[0296] This step specifically includes:

[0297] S601. Data normalization;

[0298] Since the units of the two indicators of stress and displacement are not unified, there are many inconveniences in the comprehensive risk assessment. Therefore, it is necessary to standardize the monitoring data before making a radar chart and conduct collaborative analysis of the surrounding rock characteristics.

[0299] Ⅰ. Normalize the monitoring data of the bolt sensor to the interval [0, 1]:

[0300]

[0301]

[0302]

[0303] Ⅱ. Normalize the monitoring data of the cable sensor to the interval [0, 1]:

[0304]

[0305]

[0306]

[0307] Ⅲ. Normalize the deep displacement data to the interval [0, 1]:

[0308]

[0309] Minimum pass value = 0;

[0310]

[0311] Ⅳ. Normalize the shallow displacement data to the interval [0, 1]:

[0312]

[0313] Minimum pass value = 0;

[0314]

[0315] S602. Create a standard data radar chart:

[0316] Normalize the monitoring data of the four indicators, and divide them into three cases according to the pass value and warning value, as shown in Table 1, and display them using a radar chart;

[0317] Table 1 Four monitoring indicators of roadway surrounding rock

[0318]

[0319] In the process of collaborative analysis, the three cases of the four monitoring data will be randomly combined, with a total of combinations, that is, 81 kinds. Each combination reflects a specific state of the surrounding rock. The failure characteristics of the surrounding rock and the corresponding support strategies in 81 cases are listed in detail below.

[0320] Table 2 Table of roadway abutment pressure monitoring indicators, surrounding rock characteristics and support countermeasures

[0321]

[0322]

[0323]

[0324]

[0325]

[0326]

[0327]

[0328]

[0329]

[0330]

[0331]

[0332]

[0333]

[0334]

[0335]

[0336]

[0337]

[0338]

[0339]

[0340]

[0341] 81 combinations of surrounding rock monitoring data will theoretically occur. Whenever the surrounding rock displacement monitoring equipment shows , it indicates that the monitoring equipment is faulty, and the fault types occur in 2-1 to 9, 3-1 to 9, 6-1 to 9, a total of 27 cases.

[0342] S603. Real-time data comprehensive evaluation index:

[0343] Based on data normalization, calculate the relevant indicators: the total area S of the radar chart max , the area S0 enclosed by the initial installation qualified value, the area S 预警值 enclosed by the warning value, and the area S enclosed by the radar chart of real-time monitoring data;

[0344] The calculation method is as follows:

[0345] Ⅰ. The total area S enclosed by the radar chart of normalized data max :

[0346] S max = 2

[0347] Ⅱ. The area S0 enclosed by the initial installation qualified value of the radar chart of normalized data:

[0348]

[0349] Ⅲ. The area S enclosed by the warning value of the radar chart of normalized data 预警值 :

[0350] S 预警值 = S Ⅰ预警值 + S Ⅱ预警值 + SⅢ预警值 +S Ⅳ预警值

[0351] Wherein:

[0352]

[0353]

[0354]

[0355]

[0356] Ⅳ. The area S enclosed by the radar chart of normalized real-time monitoring data:

[0357] S = S Ⅰ +S Ⅱ +S Ⅲ +S Ⅳ

[0358] Wherein:

[0359]

[0360]

[0361]

[0362]

[0363] Ⅴ. Analysis results of comprehensive evaluation indicators:

[0364] When 0 < S < S0, it indicates that the real-time monitoring data is lower than the qualified value, and the support failure or unqualified support quality should be considered;

[0365] When S0 < S i <S i预警值 , it indicates that the real-time monitoring data is within a reasonable range;

[0366] When S i >S i预警值 , potential risks should be handled according to the actual situation;

[0367] When S > S max it indicates that the support fails, and there is an extreme instability risk in the roadway surrounding rock, and measures must be taken to handle it.

[0368] In summary, in the embodiments of the present invention, the curve characteristics are analyzed by using the slope of the data secant line, and the indicators in two dimensions of force and displacement in the process of roadway abutment pressure monitoring are comprehensively considered and analyzed, reducing the analysis error of roadway abutment pressure. Moreover, a comprehensive analysis algorithm is designed. This analysis algorithm can not only analyze real-time data, but also analyze the time-varying characteristics of the monitoring data, facilitating computer autonomous recognition and analysis and putting forward reasonable support suggestions, laying a foundation for the intelligent development of coal mine roadway abutment pressure.

[0369] It should be noted that in the specification, references to "an embodiment", "embodiments", "exemplary embodiments", "some embodiments", etc. indicate that the described embodiments may include specific features, structures, or characteristics, but not necessarily every embodiment includes such specific features, structures, or characteristics. Additionally, when combining embodiments to describe a specific feature, structure, or characteristic, implementing such feature, structure, or characteristic in combination with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the relevant art.

[0370] Generally, terms can be understood, at least in part, from their use in context. For example, at least in part depending on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or can be used to describe a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey a set of exclusive factors, but rather, at least in part depending on the context, can allow for the existence of other factors that may not be explicitly described.

[0371] As used herein, the term "nominal / nominally" refers to the desired or target value of a characteristic or parameter for a component or process operation set during the design phase of a production or manufacturing process, as well as a range of values above and / or below the expected value. The range of values may be due to minor variations in the manufacturing process or tolerances. As used herein, the term "about" indicates a value of a given quantity that can vary based on a particular technology node associated with the subject semiconductor device. Based on a particular technology node, the term "about" can indicate a value of a given quantity that varies, for example, within 5%-15% of the value (e.g., ±5%, ±10%, or ±15% of the value).

[0372] It can be understood that the meanings of "on", "above", and "over" in the present disclosure should be interpreted in the broadest manner, such that "on" not only means "directly on" something, but also includes the meaning of being "on" something with intervening features or layers therebetween, and "above" or "over" not only means "above" or "over" something, but also can include the meaning of being "above" or "over" something with no intervening features or layers therebetween.

[0373] In addition, spatial relative terms such as "under", "below", "lower", "above", "upper", etc. may be used in this document for convenience of description to describe the relationship of one element or feature to another or other elements or features, as shown in the figures. Spatial relative terms are intended to cover different orientations in the use or operation of the device in addition to the orientation depicted in the figures. The device may be otherwise oriented, and the spatial relative descriptors used herein may be interpreted accordingly.

[0374] The present invention covers any alternatives, modifications, equivalent methods and solutions made to the essence and scope of the present invention. For a thorough understanding of the public of the present invention, specific details are set forth in the following preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without the description of these details. In addition, well-known methods, processes, procedures, elements and circuits, etc. are not described in detail so as not to cause unnecessary confusion to the essence of the present invention.

[0375] Those of ordinary skill in the art can understand that all or part of the steps in the methods of the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium, such as: ROM / RAM, magnetic disk, optical disk, etc.

[0376] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A warning and prediction analysis method for mine pressure monitoring equipment in coal mine roadways, characterized in that, The mine pressure monitoring equipment for coal mine roadways includes a signal converter, a bolt sensor or a cable bolt sensor, and a surrounding rock displacement sensor. The bolt sensor or the cable bolt sensor is connected to the signal converter, the surrounding rock displacement sensor is connected to the signal converter, and the signal converter is connected to a host computer; The bolt sensor or the cable bolt sensor is used to collect the force data of the roadway mine, the surrounding rock displacement sensor is used to collect the displacement data of the roadway mine, the signal converter is used to receive the force data and the displacement data, and synchronously send them to the host computer in a predetermined format. The host computer stores the data received in a predetermined format in the same database list; The early warning and prediction analysis method based on the mine pressure monitoring equipment for coal mine roadways includes the following steps: S1. Extract the characteristic values of the sensor monitoring data, including: the secant slope K, the mean value of the monitoring data the standard deviation σ of the monitoring data, and the change rate Δ of the monitoring data; S2. Analyze the stress condition of the surrounding rock of the roadway according to the characteristic values of the monitoring data of the bolt sensor or the cable bolt sensor; S3. Analyze the displacement condition of the surrounding rock of the roadway according to the characteristic values of the monitoring data of the surrounding rock displacement sensor; S4. Conduct fault diagnosis on the sensor according to the characteristic values of the monitoring data; S5. Conduct conventional monitoring data analysis on the sensor; S6. Conduct collaborative analysis on the monitoring data of the stress of the surrounding rock of the roadway and the monitoring data of the displacement of the surrounding rock of the roadway. Four indicators are derived from the two dimensions of stress and displacement: bolt stress, cable bolt stress, deep displacement, and shallow displacement. Use a radar chart to display the mutual relationship of the four indicators and obtain a comprehensive analysis result; In step S1, the secant slope K refers to the slope of the straight line formed by connecting any point on the monitoring curve and the initial data point within the analysis period. The calculation formula for the secant slope K is: The maximum value K of the secant slope max is as follows: K max = max{|tanα i |}, i ∈ (1, n) Average secant slope is as follows: Average of monitoring data The calculation formula is as follows: Where: m is the amount of measured data within the analysis period, m = n + 1; P ti is the monitoring data at each moment; The calculation formula for the standard deviation σ of the monitoring data is: The calculation formula for the change rate Δ of the monitoring data is: Step S2 includes: S201. Judge whether the monitoring data curve of the bolt sensor or the cable bolt sensor has an increasing or rising trend, and 4 conditions need to be met: Ⅰ. The change rate Δ of the data > 5%; Ⅱ. Maximum secant slope K max > 0.2; Ⅲ. Absolute value of the slope of the secant line Ⅳ. Among them, the yield strength of the bolt is 80% and the breaking strength of the cable bolt is 80%; S202. Judge whether the bolt or the cable bolt reaches the warning value, and 2 conditions need to be met: Ⅰ. Ⅱ. The change rate Δ of the data > 3%; S203. Judge whether the monitoring data curve has a decreasing or falling trend, and 3 conditions need to be met: Ⅰ. The change rate Δ of the data > 5%; Ⅱ. Average secant line slope Ⅲ. S204. Judge whether the monitoring data curve is under the action of alternating load, and 3 conditions need to be met: Ⅰ. The change rate Δ of the data > 5%; Ⅱ. Average secant line slope Ⅲ. S205. Judge whether the monitoring data curve first rises and then falls, and 3 conditions need to be met: Ⅰ. Maximum secant slope K max ≥0; Ⅱ. Average secant slope Ⅲ. S206. Judge whether the roadway bears the increase of the advanced abutment pressure of the working face, and 5 conditions need to be met: Ⅰ. Maximum secant slope K max ≥0.05; Ⅱ. When K ≥ 0.5K max The corresponding time T 0.5 is the starting point affected by the advanced abutment pressure; K max The corresponding time point T max is the peak point affected by the advanced abutment pressure; Ⅲ. At T max the distance D from the coal mining face to the monitoring device, i.e., the sensor max satisfies: 0 ≤ D max ≤ 150 m; Ⅳ.T 0.5 ≠T max ; Ⅴ. When Ⅰ→Ⅳ cannot verify whether the curve rises, manually assist the computer to judge and add a judgment program; S207. Judge whether the initial pre-tightening force of the bolt or the cable bolt is qualified and analyze the construction quality, and 4 conditions need to be met: Ⅰ. Calculate the average value of all monitoring data within 10 days after the initial installation of the bolt or cable, denoted as P mg10 or P ms10 , and use it as an index for analyzing the construction quality of the bolt or cable Ⅱ. Take 30 - 60% of the yield strength of the bolt or cable as the qualified index of the pretightening force, denoted as P MG or P MS ; Ⅲ. Qualified Index P of Bolt Pre-tightening Force mg10 ≥P MG or 20kN, it is judged as qualified; otherwise, it is judged as unqualified. Ⅳ. Qualified Index P of Anchor Cable Pre-tightening Force ms10 ≥P MS or 60kN, it is judged as qualified, otherwise, it is judged as unqualified; Step S3 includes: S301. The grading warning indicators for the displacement change of the surrounding rock of the roadway: yellow warning and red warning; Ⅰ.L max = min{bolt length × elongation rate, cable length × elongation rate}; L 预警值 = min{bolt length × elongation rate × 80%, cable length × elongation rate × 80%}; L 弹 = min{elongation in the elastic deformation stage of the bolt, elongation in the elastic deformation stage of the cable}, and this value is determined by tests; Ⅱ. Yellow warning: L 深max or L 浅max > L 弹 ; Ⅲ. Red warning: L 深max or L 浅max > L 预警值 ; S302. Only the shallow surrounding rock sends out a warning message, and 2 conditions need to be met: Ⅰ.L 深max = L 浅max ≥L 预警值 ; Ⅱ. The change rate Δ of the data > 5%; S303. Only the deep surrounding rock sends out a warning message, and 3 conditions need to be met: Ⅰ.L 深max ≥L 预警值 ; Ⅱ.L 深max > L 浅max = 0; Ⅲ. The change rate Δ of the data > 5%; S304. Displacements occur in both the deep and shallow parts of the surrounding rock, and warning information is sent out, meeting two conditions: Ⅰ.L 深max > L 浅max ≥L 预警值 ; II. The data change rate Δ > 5%; S305. The displacements in both the deep and shallow parts of the surrounding rock increase rapidly, but do not reach the warning value, meeting five conditions: Ⅰ.L 深max ≥L 浅max >0; Ⅱ.L 深max <L 预警值 ; Ⅲ. Maximum secant slope K max > 0.2; Ⅳ. Absolute value of the slope of the secant line V. The data change rate Δ > 5%; S306. When the surrounding rock displacement monitoring data is small and fluctuates, meeting two conditions: Ⅰ.L 深max <1andL 浅max <1; Ⅱ.

2. The early warning and prediction analysis method based on the mine pressure monitoring equipment for coal mine roadways according to claim 1, characterized in that, The predetermined format is: Time + MG data + MS data + WYYD data, where Time is the data acquisition time, MG data is the stress data collected by the bolt sensor, MS data is the stress data collected by the cable bolt sensor, and WYYD data is the displacement data collected by the surrounding rock displacement sensor.

3. The early warning and prediction analysis method based on the mine pressure monitoring equipment for coal mine roadways according to claim 1, characterized in that, An early warning index system is set in the host computer, including: Bolt sensor warning index: 80% of the bolt yield strength; Cable bolt sensor warning index: 80% of the cable bolt breaking strength; Butterfly-shaped surrounding rock stress stress state warning index; Surrounding rock displacement sensor warning index: 80% of the elongation rate of the bolt or cable bolt; Taking the breaking value under the fatigue damage of the bolt or cable bolt as the warning index of the support body under the alternating load; Bolt or cable bolt pre-tightening force unqualified warning index; Prediction and forecast of the range of the advanced abutment pressure of the bolt or cable bolt.

4. The early warning and prediction analysis method based on the mine pressure monitoring equipment for coal mine roadways according to claim 1, characterized in that, The analysis process of the host computer for the monitoring data includes: Analysis of the stress of the roadway surrounding rock: Judge whether the stress data exceeds the warning value. If it exceeds the warning value, send out warning information and judge whether it is a sensor false alarm. If it is not a sensor false alarm, analyze the stress state of the bolt or cable bolt, including: whether the stress of the bolt or cable bolt increases or decreases, whether the pre-tightening force of the bolt or cable bolt is qualified, whether the surrounding rock has a whole displacement, whether there is an alternating load, and whether the bolt or cable bolt bears the advanced abutment pressure; through analyzing the curve characteristics of each warning index, obtain the sub-item analysis conclusion; if it is a sensor false alarm, obtain the false alarm type according to the curve characteristics, including mutation, equipment short circuit, exceeding the threshold, and give the corresponding sensor maintenance warning; If the stress data does not exceed the warning value, conduct a conventional stress parameter analysis of the bolt or cable bolt, including the distance between the equipment and the working face, the data change rate of the bolt or cable bolt, the average value and standard deviation of the stress of the bolt or cable bolt within the cycle, generate a conventional analysis conclusion, and give the conventional analysis conclusion and safety evaluation of the equipment installation position; Analysis of the displacement of the roadway surrounding rock, including the analysis of the shallow displacement of the roadway and the analysis of the deep displacement of the roadway: Judge whether the displacement data exceeds the warning value. If it exceeds the warning value, send out warning information and judge whether it is a sensor false alarm. If it is not a sensor false alarm, analyze the shallow displacement graph and the deep displacement graph of the roadway, obtain the shallow displacement change rate and the shallow displacement amount, as well as the deep displacement change rate and the deep displacement amount, obtain the surrounding rock separation amount according to the shallow displacement amount and the deep displacement amount, and then obtain the surrounding rock movement analysis conclusion; if it is a sensor false alarm, obtain the false alarm type according to the curve characteristics, including mutation, equipment short circuit, reverse of the deep or shallow base point, and give the corresponding sensor maintenance warning; If the displacement data does not exceed the warning value, routine analysis of surrounding rock movement data is carried out, including the distance between the equipment and the working face, the setting of the monitoring equipment base point, the extreme value and average value analysis of the separation layer within the cycle, generating a routine analysis conclusion, and giving the routine analysis conclusion and safety evaluation of the equipment installation position; After that, the collaborative analysis of the stress and displacement of the roadway surrounding rock is carried out, giving an overall analysis conclusion and providing corresponding control strategies.

5. The early warning and prediction analysis method based on the mine pressure monitoring equipment for coal mine roadways according to claim 1, characterized in that, Step S4 includes: S401. The data change rate Δ = 0 or NaN%, indicating that there is a fault in the monitoring sensor and it cannot transmit data normally; S402. Judge whether there are jump values in the monitoring data curve: meet 3 conditions: Ⅰ. Maximum secant slope |K max | > 3; Ⅱ. Ⅲ. The data change rate Δ < 20%; S403. There is a principle error in the use of the surrounding rock displacement sensor; Ⅰ.L 深max <L 浅max ; Step S5 includes: S501. Routine analysis conclusion of the surrounding rock displacement sensor: the installation position of the sensor, the depth of the deep base point, the depth of the shallow base point, the maximum value, minimum value, and average value of the deep base point data shown by the monitoring data, and the maximum value, minimum value, and average value of the shallow base point data; S502. Routine analysis conclusion of the bolt sensor or cable bolt sensor: the installation position of the sensor, the initial pre-tightening force, the stable stress condition of the bolt or cable bolt, the distance between the working face and the sensor, the data change rate within the analysis period, and the pressure change condition of the bolt or cable bolt.

6. The early warning and prediction analysis method for the mine pressure monitoring equipment based on the coal mine roadway according to claim 1, wherein, Step S6 includes: S601. Data normalization: Ⅰ. Normalize the monitoring data of the bolt sensor to the interval [0, 1]: Ⅱ. Normalize the monitoring data of the cable bolt sensor to the interval [0, 1]: Ⅲ. Normalize the deep displacement data to the interval [0, 1]: The minimum qualified value = 0; Ⅳ. Normalize the shallow displacement data to the interval [0, 1]: The minimum qualified value = 0; S602. Make a standard data radar chart: Normalize the monitoring data of the four indicators, and divide them into three situations according to the qualified value and warning value, and display them using a radar chart; S603. Real-time data comprehensive evaluation index: Based on data normalization, calculate relevant indicators: the total area S of the radar chart max , the area S0 enclosed by the initial installation qualified value, and the area S 预警值 enclosed by the early warning value; the area S enclosed by the radar chart of real-time monitoring data The calculation method is as follows: Ⅰ. Total area S enclosed by the normalized data radar chart max : S max ＝2 Ⅱ. The area S0 enclosed by the initial installation qualified value of the normalized data radar chart: Ⅲ. Area S enclosed by the warning value of the normalized data radar chart 预警值 : S 预警值 = S Ⅰ预警值 + S Ⅱ预警值 + S Ⅲ预警值 + S Ⅳ预警值 In the formula: Ⅳ. The area S enclosed by the normalized real-time monitoring data radar chart: S = S Ⅰ + S Ⅱ + S Ⅲ + S Ⅳ In the formula: Ⅴ. Analysis result of the comprehensive evaluation index: When 0 < S < S0, it indicates that the real-time monitoring data is lower than the qualified value, and it should be considered that the support fails or the support quality does not meet the standard; When S0 < S i < S i预警值 , it indicates that the real-time monitoring data is within a reasonable range; When S i > S i预警值 , potential risks should be addressed according to the actual situation; When S > S max it indicates that the support has failed and there is an extreme risk of instability in the surrounding rock of the roadway, and measures must be taken to deal with it.

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