A mining face support monitoring system and method

Abstract

The present invention discloses a support monitoring system and method for a mining face, comprising: a data acquisition module, a database, a support installation analysis module, a support monitoring module and a monitoring verification module. The data acquisition module is used to collect geological data and support parameter data at the mining work site, and the database is used to store all the collected data. The support installation analysis module is used to analyze geological change time and support installation data, and the best time to start installing anchor rods is predicted. The support monitoring module is used to monitor the anchor rod change data after installation in real time. The monitoring verification module is used to test the stress state of abnormal anchor rods, confirm and maintain failed anchor rods, monitor the process of supporting by installing anchor rods, monitor the support effect of the anchor rods, reduce the probability of roof collapse and injury accidents caused by poor support effect, and predict the best time to reduce the number of times reinforced anchor rods are added during mining work, thereby reducing the work intensity of staff.

Description

Technical Field

[0001] The present invention relates to the technical field of support monitoring, and in particular to a mining face support monitoring system and method. Background Art

[0002] The support of the mining face refers to the operation of supporting the coal mining face to maintain the safety of the working space. The rock layer above the coal seam is the roof, which includes the direct roof. The direct roof is the object of the coal mining face support. Supporting the roof during mining can effectively prevent roof accidents. For short-wall coal mining, anchor support is usually used for support. However, if the support effect is not good, it is easy to cause roof collapse and injury. Therefore, it is necessary to monitor the support work to improve the safety of mining work;

[0003] However, there are the following problems in the monitoring process of anchor support: first, the more appropriate the timing of anchor installation, the better the support effect. Due to the frequent geological changes caused by coal mining in the mining area, failed anchors often appear. Every time a failed anchor appears, the staff needs to add reinforcing anchors around the failed anchor, which increases the work intensity. The existing technology randomly selects the time to start installing anchors, and cannot effectively extend the duration of the anchor support effect to reduce the number of additional installations, thereby reducing the work intensity of the staff; secondly, anchors with abnormal stress states will lose their support effect. The existing technology generally uses real-time monitoring of the stress state of each anchor to find failed anchors, and cannot reduce the monitoring cost while speeding up the speed of finding failed anchors.

[0004] Therefore, people need a mining face support monitoring system and method to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a mining face support monitoring system and method to solve the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a mining face support monitoring system, the system comprising: a data acquisition module, a database, a support installation analysis module, a support monitoring module and a monitoring verification module;

[0007] The data acquisition module is used to collect geological data and support parameter data at the mining work site;

[0008] The database is used to store all collected data;

[0009] The support installation analysis module is used to analyze geological change time and support installation data, and predict the best time to start installing anchor bolts;

[0010] The support monitoring module is used to monitor the change data of the anchor rod after installation in real time to determine whether the anchor rod is abnormal;

[0011] The monitoring and verification module is used to test the stress state of abnormal anchor rods, confirm and maintain failed anchor rods, use pressure sensors to test the stress state of abnormal anchor rods, and support the coal seam roof by anchor rod support.

[0012] Furthermore, the data acquisition module includes a geological data acquisition unit and an installation data acquisition unit. The geological data acquisition unit is used to collect geological change time data at the mining work site; the installation data acquisition unit is used to collect duration data of previous anchor support installation work and transmit all collected data to the database.

[0013] Furthermore, the support installation analysis module includes a geological change analysis unit and an installation timing prediction unit. The geological change analysis unit is used to analyze geological change time data and transmit the geological change time data to the installation timing prediction unit; the installation timing prediction unit is used to analyze the duration data of anchor support installation work, and combine the installation duration data and the geological change time data to predict the best time to start installing the anchor.

[0014] Furthermore, the support monitoring module includes an external status monitoring unit and an abnormal support warning unit. The external status monitoring unit is used to collect the actual installed anchor drilling angle data using an angle sensor after the anchor installation is completed, and to collect the angle change data between the installed anchor and the top plate in real time; the abnormal support warning unit is used to analyze whether the anchor is abnormal through the angle change data: if the anchor is abnormal, an anchor warning signal is sent to the monitoring and verification module.

[0015] Furthermore, the monitoring and verification module includes a stress state testing unit and a failed anchor rod maintenance unit. The stress state testing unit is used to test whether the stress state of the anchor rod is abnormal after receiving an abnormal anchor rod warning signal, and judge the anchor rod with abnormal stress state as a failed anchor rod; the failed anchor rod maintenance unit is used to maintain the failed anchor rod detected by the test: adding reinforcing anchor rods around the failed anchor rod.

[0016] A method for monitoring support of a mining working face comprises the following steps:

[0017] Z1: Collect geological data and support installation data at the mining site;

[0018] Z2: retrieve and analyze geological change data and anchor installation time data to predict the best time to start anchor installation;

[0019] Z3: Real-time monitoring of anchor rod change data after installation to determine whether the anchor rod is abnormal: if the anchor rod is not abnormal, continue to monitor the anchor rod change data; if the anchor rod is abnormal, issue a warning signal and execute step Z4;

[0020] Z4: Test the stress state of the anchor rod: if there is no anchor rod with abnormal stress state, execute step Z3; if there is an anchor rod with abnormal stress state, execute step Z5;

[0021] Z5: Screen out anchors with abnormal stress status as failed anchors and perform maintenance on the failed anchors.

[0022] Furthermore, in step Z1: in the historical mining work, the time set for starting to install the anchor rod is collected as T = {T1, T2, ..., Tn}, the time set required for each anchor rod installation is t = {t1, t2, ..., tn}, the number of anchor rods installed is B = {B1, B2, ..., Bn}, and the number of anchor rod failures monitored during the installation of the anchor rod is M = {M1, M2, ..., Mn}, where n represents the number of selected times of the collected anchor rod installation start time, and in the process of a random anchor rod installation: the number of geological changes monitored at the mining work site is m, and the interval time set of geological changes is t' = {t1', t2', ..., tn}. m-1 '}, m≥2, the time interval set of anchor failure monitoring is t"={t1",t2",…,tg"}, and the number of failed anchors collected each time is A={A1,A2,…,A g+1}, where g+1 represents the number of times the anchor failure is detected during a random anchor installation process, g+1=Mi, and the start time of the mining work is the same;

[0023] In step Z2: the reliability Qi of the time for starting to install the anchor bolt randomly selected in the past is calculated according to the following formula:

[0024]

[0025] Among them, Mi represents the number of times the anchor failure is monitored during a random anchor installation, Aj represents the number of failed anchors monitored at a random time, tj' represents the interval time of geological changes during a random anchor installation, and tj" represents the time interval between the j+1th and jth monitoring of anchor failure during a random anchor installation. The reliability set of the selected time to start installing the anchor is Q = {Q1, Q2, ..., Qn}. When mining work is carried out at the same time stage, the time for historical support, i.e., the time for starting the installation of the anchor, is different. The time interval data of geological changes in the mining area monitored by big data analysis can be used to determine the selection of different installation methods. Installation time, frequency of geological changes, the more frequent the geological changes, the greater the possibility of failed anchors when installing anchors at the corresponding time, that is, the less reliable the corresponding selected time; at the same time, analyze the failed anchor data actually monitored: the more failed anchors monitored within the corresponding time and the more frequently the failed anchors are monitored, the lower the reliability of the selected time. The purpose of calculating the reliability of the selected time by combining the anchor failure data and the geological change data is to select the most reliable time as the benchmark time for prediction. The historically selected installation time is often selected based on the experience of the staff, which is of reference value and is conducive to improving the accuracy of the benchmark time selection results.

[0026] Furthermore, the best time to start installing anchors is predicted: the reliability of the selected time to start installing anchors is compared, and the time corresponding to the highest reliability: Qmax is used as the reference time, the reference time is T', T'∈T, and the number of anchors that need to be installed is obtained as k. The best time to start installing anchors is predicted according to the following formula:

[0027]

[0028] Among them, ti represents the time required to install the anchor in a random installation process, Bi represents the number of anchors installed in the corresponding process, and t 准 Indicates the time required to install the anchor during the installation process corresponding to the reference time T', and predicts T 装 For the best time to start installing anchors, the support duration for different mining operations will vary depending on the number of anchors installed. Directly selecting the most reliable time as the time to start installing anchors will result in error data, which will affect the prediction results. The most reliable time selected based on historical data will be used as the benchmark time, and the installation time difference will be used as the time that needs to be advanced. The benchmark time will be advanced rather than delayed, and anchor installation will begin at the corresponding predicted time. This will help reduce the number of times additional reinforced anchors are installed during mining work, and at the same time, the anchor installation can be completed in time to help carry out mining work.

[0029] Furthermore, in step Z3: after the bolt installation is completed, the bolt change data after installation is monitored in real time: the bolts are numbered according to the installation order, and a tangent plane of the top plate is made through a random point on the top plate of the mining work site, and the set of angles between the actually installed bolts and the tangent plane is obtained as α = {α1, α2, ..., αk}, and the data points {(1, α1), (2, α2), ..., (1, αk)} are fitted by the least squares method: the first fitting function is obtained: f1(x) = Cx + D, where C and D represent the first Fitting coefficient, after the bolt is installed, mining work is carried out: during the mining process, the set of angles between the random bolt and the cutting plane is monitored as α′={α1′, α2′, …, αk′}, and the data points {(1, α1′), (2, α2′), …, (1, αk′)} are fitted by the least squares method: the second fitting function is obtained: f2(x)=Ex+F, where E and F represent the second fitting coefficients, and whether the bolt is abnormal is determined: if C=E, it means that the slopes of the first fitting function and the second fitting function are the same. According to Determine whether the anchor rod is abnormal: If It means that the two fitting lines coincide, and it is judged that the anchor installation angle has not changed and the anchor has no abnormality; if C≠E or It indicates that the two fitting lines do not overlap, and it is judged that the anchor installation angle has changed and the anchor is abnormal, and an anchor abnormality warning signal is issued;

[0030] In step Z4-Z5: after receiving the abnormal anchor warning signal, the stress state of the anchor is tested: the anchor with abnormal stress state is judged as a failed anchor, and reinforced anchors are added around the failed anchor. After the addition, the anchor angle is continuously monitored, and the angle between the installed anchor and the coal seam roof is analyzed. The anchor angle data is linearly fitted, which is beneficial to observe whether there is any deviation in the anchor installation position caused by geological changes during the mining process, and to help timely warn and find failed anchors. Since most roofs are irregular in shape, accurate angle data cannot be obtained, and analyzing the angle between the tangent plane of the roof at a certain point and the anchor is beneficial to improve the accuracy of the monitoring effect; monitoring the stress state after abnormal deformation of the anchor is detected is beneficial to verify whether there is a failed anchor. Monitoring the overall situation first is beneficial to speed up the search for failed anchors.

[0031] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0032] The present invention monitors the process of supporting by installing anchor rods in mining work, which is conducive to timely monitoring the supporting effect of anchor rods and issuing early warnings, thereby reducing the probability of roof collapse and injury accidents caused by poor supporting effect; monitoring the timing of anchor rod installation: judging different installation times through big data analysis of the time interval data of geological changes in the mining area monitored, the frequency of geological changes, and the reliability of the anchor rod installation start time selected in the mining work in the same historical period combined with the actual monitored failed anchor rod data are analyzed, and the time with the highest reliability is selected as the prediction reference time, combined with the analysis of the time deviation caused by different numbers of installed anchor rods, the best time to start installing the anchor rod is predicted, which reduces the number of times additional reinforced anchor rods are installed in the mining work, and can complete the installation of the anchor rod in time, which helps to carry out the mining work and reduces the work intensity of the staff; monitoring the support effect: firstly, the external deformation of the anchor rod is monitored as a whole, and then the internal stress state is monitored to speed up the detection of failed anchor rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0034] Figure 1 It is a structural diagram of a mining face support monitoring system of the present invention;

[0035] Figure 2 It is a flow chart of a mining face support monitoring method of the present invention. DETAILED DESCRIPTION

[0036] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0037] See also Figure 1-Figure 2 , the present invention provides a technical solution: a mining face support monitoring system, the system includes: a data acquisition module, a database, a support installation analysis module, a support monitoring module and a monitoring verification module;

[0038] The data acquisition module is used to collect geological data and support parameter data at the mining site;

[0039] The database is used to store all the collected data;

[0040] The support installation analysis module is used to analyze geological change time and support installation data to predict the best time to start installing anchor bolts;

[0041] The support monitoring module is used to monitor the change data of the anchor rod after installation in real time to determine whether there is any abnormality in the anchor rod;

[0042] The monitoring and verification module is used to test the stress status of abnormal anchor rods and to confirm and maintain failed anchor rods.

[0043] The data acquisition module includes a geological data acquisition unit and an installation data acquisition unit. The geological data acquisition unit is used to collect geological change time data at the mining site; the installation data acquisition unit is used to collect duration data of previous anchor support installation work and transmit all collected data to the database.

[0044] The support installation analysis module includes a geological change analysis unit and an installation timing prediction unit. The geological change analysis unit is used to analyze the geological change time data and transmit the geological change time data to the installation timing prediction unit; the installation timing prediction unit is used to analyze the duration data of the anchor support installation work, and combine the installation duration data and the geological change time data to predict the best time to start installing the anchor.

[0045] The support monitoring module includes an external status monitoring unit and an abnormal support warning unit. The external status monitoring unit is used to collect the actual installed anchor drilling angle data using the angle sensor after the anchor installation is completed, and to collect the angle change data between the installed anchor and the top plate in real time; the abnormal support warning unit is used to analyze whether there is any abnormality in the anchor through the angle change data: if there is any abnormality in the anchor, an anchor warning signal is sent to the monitoring and verification module.

[0046] The monitoring and verification module includes a stress state testing unit and a failed anchor rod maintenance unit. The stress state testing unit is used to test whether the stress state of the anchor rod is abnormal after receiving the anchor rod abnormal warning signal, and judge the anchor rod with abnormal stress state as a failed anchor rod; the failed anchor rod maintenance unit is used to maintain the failed anchor rod detected by the test: adding reinforcing anchor rods around the failed anchor rod.

[0047] A method for monitoring support of a mining working face comprises the following steps:

[0048] Z1: Collect geological data and support installation data at the mining site;

[0049] Z2: retrieve and analyze geological change data and anchor installation time data to predict the best time to start anchor installation;

[0050] Z3: Real-time monitoring of anchor rod change data after installation to determine whether the anchor rod is abnormal: if the anchor rod is not abnormal, continue to monitor the anchor rod change data; if the anchor rod is abnormal, issue a warning signal and execute step Z4;

[0051] Z4: Test the stress state of the anchor rod: if there is no anchor rod with abnormal stress state, execute step Z3; if there is an anchor rod with abnormal stress state, execute step Z5;

[0052] Z5: Screen out anchors with abnormal stress status as failed anchors and perform maintenance on the failed anchors.

[0053] In step Z1: in the historical mining work, the time set of the selected start time of anchor installation is T = {T1, T2, ..., Tn}, the time set required for each anchor installation is t = {t1, t2, ..., tn}, the number of anchors installed is B = {B1, B2, ..., Bn}, and the number of anchor failures monitored during the installation of anchors is M = {M1, M2, ..., Mn}, where n represents the number of selected times of the collected anchor installation start time. In the process of random anchor installation: the number of geological changes monitored at the mining site is m, and the interval time set of geological changes is t' = {t1', t2', ..., tn}. m-1 '}, m≥2, the time interval set of anchor failure monitoring is t"={t1",t2",…,tg"}, and the number of failed anchors collected each time is A={A1,A2,…,A g+1}, where g+1 represents the number of times the anchor failure is detected during a random anchor installation process, g+1=Mi, and the time when the mining work starts is the same;

[0054] In step Z2: the reliability Qi of the time for starting to install the anchor bolt randomly selected in the past is calculated according to the following formula:

[0055]

[0056] Wherein, Mi represents the number of times anchor failure is monitored during a random anchor installation process, Aj represents the number of failed anchors monitored at a random time, tj' represents the interval time of geological changes during a random anchor installation process, and tj" represents the time interval between the j+1th and jth monitoring of anchor failure during a random anchor installation process. The reliability set of the selected time to start anchor installation is Q = {Q1, Q2, ..., Qn}. The historically selected installation time is often selected based on the experience of the staff and is of reference value. The benchmark time in the prediction result is selected based on the historically selected installation time, which improves the accuracy of the benchmark time selection result.

[0057] Predict the best time to start installing anchors: Compare the reliability of the selected time to start installing anchors, and take the time corresponding to the highest reliability: Qmax as the reference time, the reference time is T', T'∈T, and the number of anchors that need to be installed is k. The best time to start installing anchors is predicted according to the following formula:

[0058]

[0059] Among them, ti represents the time required to install the anchor in a random installation process, Bi represents the number of anchors installed in the corresponding process, and t 准 Indicates the time required to install the anchor during the installation process corresponding to the reference time T', and predicts T 装 In order to find the best time to start installing anchor bolts, combined with the analysis of the time deviation caused by installing different numbers of anchor bolts, the best time to start installing anchor bolts is predicted. This reduces the number of times additional reinforced anchor bolts are installed during mining work, and at the same time, the anchor bolts can be installed in time to help carry out mining work and reduce the workload of staff.

[0060] In step Z3: after the bolt is installed, the bolt change data after installation is monitored in real time: the bolts are numbered according to the installation order, and a tangent plane of the top plate is made through a random point on the top plate of the mining work site, and the set of angles between the actually installed bolts and the tangent plane is obtained as α = {α1, α2, ..., αk}. The data points {(1, α1), (2, α2), ..., (1, αk)} are fitted by the least squares method: the first fitting function is obtained: f1(x) = Cx + D, where C and D represent the first fitting system. After the bolt is installed, mining is carried out: During the mining process, the set of angles between the random bolt and the cutting plane is monitored as α′={α1′, α2′, …, αk′}. The data points {(1, α1′), (2, α2′), …, (1, αk′)} are fitted by the least squares method: The second fitting function is obtained: f2(x)=Ex+F, where E and F represent the second fitting coefficients. It is used to determine whether the bolt is abnormal: If C=E, it means that the slope of the first fitting function is the same as that of the second fitting function. According to Determine whether the anchor rod is abnormal: If It means that the two fitting lines coincide, and it is judged that the anchor installation angle has not changed and the anchor has no abnormality; if C≠E or It indicates that the two fitting lines do not overlap, and it is judged that the anchor installation angle has changed and the anchor is abnormal, and an anchor abnormality warning signal is issued;

[0061] In steps Z4-Z5: after receiving the abnormal anchor rod warning signal, the stress state of the anchor rod is tested: the anchor rod with abnormal stress state is judged as a failed anchor rod, and reinforced anchor rods are added around the failed anchor rod. After the addition, the anchor rod angle is continuously monitored. Timely warning speeds up the detection of failed anchor rods and improves the safety of mining work.

[0062] Embodiment 1: In the historical mining work, the selected time to start installing the anchor rod is collected as T1: March 20th of each year; T2: May 5th of each year; T3: March 1st of each year, the time required for each anchor rod installation is t = {t1, t2, t3} = {30, 50, 20}, the unit is: day, the number of anchor rods installed is B = {B1, B2, B3} = {100, 45, 75}, and the number of anchor rod failures monitored during the installation process is M = {M1, M2, M3}={10,3,5}, in the process of randomly installing anchor bolts: the number of geological changes detected at the mining site is m=3, the geological change interval time set is t'={t1',t2'}={10,60}, the unit is: day, the time interval set of anchor bolt failure is t"={t1",t2",t3"}={2,10,15}, the number of failed anchor bolts collected each time is A={A1,A2,A3,A4}={5,2,10,6}, according to the formula Calculate the reliability of the time for starting to install the anchor bolts randomly selected in the past Qi≈44. The reliability set of the time for starting to install the anchor bolts selected by the same calculation method is Q={Q1,Q2,Q3}={44,50,68}. The time corresponding to the highest reliability: Qmax=68 is used as the reference time. The reference time is T=T3: On March 1st of each year, the number of anchor bolts that need to be installed is obtained as k=200. According to the formula Predicted best time to start anchor installation: T installation: January 20th of each year, predicted T 装 The best time to start installing anchors;

[0063] Embodiment 2: After the bolt is installed, the bolt change data after installation is monitored in real time: the bolts are numbered according to the installation order, and a tangent plane of the top plate is made through a random point on the top plate of the mining work site, and the set of angles between the actually installed bolts and the tangent plane is obtained as α = {α1, α2, α3} = {π / 4, π / 2, π / 3}. The data points {(1, α1), (2, α2), (1, α3)} are fitted by the least squares method: the first fitting function is obtained: f1(x) = Cx + D = 0.13x + 0.8 7. After the bolt is installed, mining is carried out: During the mining process, the angle set between the random bolt and the cutting plane is monitored to be α′={α1′, α2′, α3′}={π / 4, 2π / 3, π / 3}. The data points {(1, α1′), (2, α2′), (1, α3′)} are fitted by the least squares method: the second fitting function is obtained: f2(x)=Ex+F=0.13x+1.05. It is judged whether the bolt is abnormal: C=E, which means that the slope of the first fitting function is the same as that of the second fitting function. This indicates that the two fitting straight lines do not coincide with each other. It is judged that the anchor installation angle has changed and the anchor is abnormal, and an abnormal anchor warning signal is issued. The stress state of the anchor is tested: the anchor with abnormal stress state is judged to be a failed anchor, and reinforcing anchors are added around the failed anchor. After the addition, the anchor angle continues to be monitored.

[0064] Finally, it should be noted that the above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, 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 mining face support monitoring system, characterized in that: The system includes: a data acquisition module, a database, a support installation analysis module, a support monitoring module and a monitoring verification module; The data acquisition module is used to collect geological data and support parameter data at the mining work site; The database is used to store all collected data; The support installation analysis module is used to analyze geological change time and support installation data, and predict the best time to start installing anchor bolts; The support monitoring module is used to monitor the change data of the anchor rod after installation in real time to determine whether the anchor rod is abnormal; The monitoring and verification module is used to test the stress state of abnormal anchor rods, confirm and maintain failed anchor rods; The data acquisition module includes a geological data acquisition unit and an installation data acquisition unit. The geological data acquisition unit is used to collect geological change time data at the mining site; the installation data acquisition unit is used to collect the duration data of the previous bolt support installation work, and transmit all the collected data to the database; The support installation analysis module includes a geological change analysis unit and an installation timing prediction unit. The geological change analysis unit is used to analyze geological change time data and transmit the geological change time data to the installation timing prediction unit. The installation timing prediction unit is used to analyze the duration data of the anchor support installation work and predict the best time to start installing the anchor in combination with the installation duration data and the geological change time data. The support monitoring module includes an external state monitoring unit and an abnormal support warning unit. The external state monitoring unit is used to collect the actual installed anchor drilling angle data using an angle sensor after the anchor is installed, and collect the angle change data between the installed anchor and the top plate in real time; the abnormal support warning unit is used to analyze whether the anchor is abnormal through the angle change data: if the anchor is abnormal, send an anchor warning signal to the monitoring verification module; The monitoring and verification module includes a stress state testing unit and a failed anchor rod maintenance unit. The stress state testing unit is used to test whether the stress state of the anchor rod is abnormal after receiving an abnormal anchor rod warning signal, and judge the anchor rod with abnormal stress state as a failed anchor rod; the failed anchor rod maintenance unit is used to maintain the failed anchor rod detected by the test: adding reinforcing anchor rods around the failed anchor rod.

2. A mining face support monitoring method, characterized in that: The following steps are involved: Z1: Collect geological data and support installation data at the mining site; Z2: retrieve and analyze geological change data and anchor installation time data to predict the best time to start anchor installation; Z3: Real-time monitoring of anchor rod change data after installation to determine whether the anchor rod is abnormal: if the anchor rod is not abnormal, continue to monitor the anchor rod change data; if the anchor rod is abnormal, issue a warning signal and execute step Z4; Z4: Test the stress state of the anchor rod: if there is no anchor rod with abnormal stress state, execute step Z3; if there is an anchor rod with abnormal stress state, execute step Z5; Z5: Screen out anchors with abnormal stress states as failed anchors and perform maintenance on them; In step Z1: in the historical mining work, the time set of the selected start time of anchor installation is T={T1, T2, ..., Tn}, the time set required for each anchor installation is t={t1, t2, ..., tn}, the number of anchors installed is B={B1, B2, ..., Bn}, and the number of anchor failures monitored during the installation of anchors is M={M1, M2, ..., Mn}, where n represents the number of selected start times of anchor installation collected. In a random installation of anchors: the number of geological changes monitored at the mining site is m, and the interval time set of geological changes is t ’ ={t1 ’ , t2 ’ ,…,t m-1 ’ }, m≥2, the time interval set for monitoring anchor failure is t ’’ ={t1 ’’ , t2 ’’ ,…,tg ’’ }, the number of failed anchors collected each time is A={A1, A2, …, A g+1 }, where g+1 represents the number of times the anchor failure is monitored during a random anchor installation process, g+1=Mi, and the time when the mining work starts is the same; In step Z2: the reliability Qi of the time for starting to install the anchor bolt randomly selected in the past is calculated according to the following formula: ； Among them, Mi represents the number of times the anchor failure is detected during a random installation of anchors, Aj represents the number of failed anchors detected at a random time, and tj ’ Indicates the interval time of geological changes during the random installation of anchor bolts, tj ’’ Indicates the time interval between the j+1th and jth monitoring of anchor failure in a random anchor installation process, and the reliability set of the selected time to start anchor installation is Q={Q1, Q2, …, Qn}; Predict the best time to start installing anchor bolts: Compare the reliability of the selected time to start installing anchor bolts, and take the time corresponding to the highest reliability: Qmax as the reference time, which is T ’ , T ’ ∈T, the number of anchors that need to be installed is obtained as k, and the best time to start installing anchors is predicted according to the following formula: ； Among them, ti represents the time required to install the anchor in a random installation process, Bi represents the number of anchors installed in the corresponding process, and t 准 Indicates the reference time T ’ Corresponding to the installation process of anchor bolts, the time required to install the anchor bolts is predicted to be T 装 The best time to start installing anchors; In step Z3: after the bolt is installed, the bolt change data after installation is monitored in real time: the bolts are numbered according to the installation order, and a tangent plane is made at a random point on the top plate of the mining site, and the set of angles between the actually installed bolts and the tangent plane is obtained as ={ , , …, }, for data points {(1, ), (2, ),…,(1, )} Perform straight line fitting by least squares method: get the first fitting function: , where C and D represent the first fitting coefficients. After the bolt is installed, mining is carried out: During the mining process, the set of angles between the bolt and the cutting plane is monitored randomly: ={ , , …, }, for data points {(1, ), (2, ),…,(1, )} Perform straight line fitting by the least squares method: Get the second fitting function: , where E and F represent the second fitting coefficients, which are used to determine whether the anchor bolt is abnormal: If C=E, it means that the slopes of the first fitting function and the second fitting function are the same. Determine whether the anchor rod is abnormal: If , indicating that the two fitting lines coincide, judging that the anchor bolt installation angle has not changed and the anchor bolt has no abnormality; if or , indicating that the two fitting lines do not overlap, judging that the anchor installation angle has changed and the anchor is abnormal, and issuing an anchor abnormality warning signal; In step Z4-Z5: after receiving the anchor rod abnormal warning signal, the stress state of the anchor rod is tested: the anchor rod with abnormal stress state is judged as a failed anchor rod, and reinforcing anchor rods are added around the failed anchor rod, and the anchor rod angle is continuously monitored after the addition.

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