Column damage staging early warning method based on micro-seismic single-channel event

Abstract

The invention belongs to the technical field of mine safety monitoring, and particularly relates to an ore pillar damage staging early warning method based on a micro-seismic single-channel event, which is characterized by comprising the following steps: step 1, carrying out a rock acoustic emission characteristic test to obtain acoustic emission characteristics in an ore pillar damage process; step 2, analyzing the full life cycle of ore pillar destructive inoculation; according to the acoustic emission change speed in the rock destruction process, the full life cycle of jamb destruction inoculation is divided; step 3, establishing a ground pressure micro-seismic monitoring system, realizing real-time monitoring of mine pillar damage disasters, and obtaining a single-channel micro-seismic event change result in real time; and step 4, performing early warning analysis on the ore pillar damage staging, analyzing the change speed of the single-channel event according to the ore pillar damage inoculation process, giving an ore pillar damage development stage, and realizing accurate early warning on the ore pillar damage staging. According to the invention, the full life cycle monitoring of the mine pillar destroy inoculation process can be realized, and the potential pillar destroy can be accurately pre-warned by stages.

Description

Technical Field

[0001] The invention belongs to the technical field of mine safety monitoring, and in particular relates to a phased early warning method for mine pillar destruction based on microseismic single-channel events. Background Art

[0002] With the exploitation of mineral resources by underground mining companies, ground pressure disasters that were originally complex and difficult to predict have become more frequent. Experts and scholars at home and abroad have studied many methods and technologies for ground pressure disaster monitoring and early warning, among which microseismic monitoring is an effective way to warn of ground pressure disasters. Zhao Xingdong used microseismic monitoring, surrounding rock stress accumulation, stress shadow, and stress migration for the prediction of mine rock burst; Dou Linming established a multi-parameter prediction and spatiotemporal monitoring and early warning system for coal rock burst danger "stress field-vibration field", realizing the analysis and prediction of impact danger and real-time monitoring and early warning; Dang Mingzhi proposed a ground pressure disaster early warning analysis method based on microseismic moment magnitude by optimizing the microseismic monitoring network and adopting multi-parameter analysis combined with a single ground pressure manifestation; Guo Xiaoqiang, Qin Min, etc., based on the microseismic event database, constructed a ground pressure disaster early warning system including time, space, and seismological parameters; Huang Yanwei proposed a microseismic disaster early warning system from the perspective of production safety management. A ground pressure disaster early warning system integrating disaster warning, disaster level classification, on-site disposal and safe production management was established; Tian Honghai used the K-means clustering analysis algorithm to divide the Jingtieshan Huashugou Copper Mine into five microseismic monitoring areas, and established a disaster early warning method based on the number of microseismic monitoring events, the cumulative number of microseismic monitoring events, the βn distribution and the CUFIT model, and successfully issued an early warning for the ground pressure disaster events in the fourth monitoring area in the mining area; Zhang Xuemei verified the feasibility of microseismic monitoring technology in deep well disaster early warning through the spatiotemporal distribution of microseismic monitoring events, the disaster precursor characteristic b value and the H index, and by corroborating with the rock burst in the mining area.

[0003] At present, most ground pressure disaster monitoring and early warning methods basically use one or more warning parameters. When the monitoring data reaches the warning value, a warning is immediately issued. These methods are insufficient in warning accuracy and cannot accurately judge the life cycle of ground pressure disasters, nor can they give the development stage of ground pressure disasters. Summary of the invention

[0004] The purpose of the present invention is to propose a phased early warning method for pillar destruction based on microseismic single-channel events, which monitors and analyzes the entire process of pillar destruction development and can accurately give the incubation stage of pillar destruction development, thereby achieving accurate early warning of pillar destruction.

[0005] The objective of the present invention is achieved through the following technical solutions: The method for early warning of pillar damage in stages based on microseismic single-channel events of the present invention is characterized by comprising the following steps: Step 1: Conduct a rock acoustic emission characteristic test, conduct a uniaxial compression failure acoustic emission test on the target mine rock, and obtain the acoustic emission characteristics of the rock failure process; Step 2: Analysis of the whole life cycle of pillar damage incubation: According to the speed of acoustic emission change during rock damage, the whole life cycle of pillar damage disaster incubation is divided into initial incubation period, constant speed incubation period, initial accelerated incubation period, accelerated incubation period and impending damage period; Step 3: Establish a ground pressure microseismic monitoring system to achieve real-time monitoring of mine pillar damage and obtain the results of single-channel microseismic event changes in real time; Step 4: Early warning analysis of pillar damage in stages: analyze the change rate of single-channel events against the incubation process of pillar damage, and give the development stage of pillar damage, so as to achieve accurate early warning of pillar damage in stages.

[0006] In the step 1, the rock to be tested in the mine is processed into a cuboid sample; the loading system adopts a hydraulic universal material testing machine and adopts a stress-controlled loading method; the monitoring system includes an acoustic emission sensor, an acoustic emission preamplifier, an acoustic emission card, an acoustic emission host system and an acoustic emission processing software.

[0007] In the step 2, a uniaxial compression test of rock is carried out using a rock acoustic emission test system. Accompanied by the initiation and expansion of microcracks and the generation of macroscopic damage, a large number of acoustic emission signals are released in the whole process. According to a large number of acoustic emission characteristic results of rock uniaxial compression damage, the acoustic emission events of rock from loading to damage can be roughly divided into four stages: the initial growth stage of OA acoustic emission events, the calm stage of AB acoustic emission, the initial accelerated growth stage of BC acoustic emission events, and the accelerated growth stage of CD acoustic emission events.

[0008] In step 2, during the entire life cycle of the pillar destruction, Initial incubation period: that is, the initial increase stage of acoustic emission, during which the stress on the rock mass begins to increase and the internal discontinuities begin to compact, which will produce more microseismic events; Isokinetic incubation period: that is, the acoustic emission quiet period, during which the stress on the rock mass continues to increase, but still fails to cause a large number of fractures inside the rock mass, and this process will not produce many microseismic events; Initial acceleration incubation period: that is, the initial acceleration increase stage of acoustic emission. During this stage, the force on the rock mass continues to increase, resulting in a certain degree of fracture inside the rock mass. This process will produce more microseismic events; Accelerated incubation period: that is, the stage of accelerated increase of acoustic emission. During this stage, the force on the rock mass is close to its own strength, which will cause a large number of cracks inside the rock mass. This process will produce a large number of microseismic events and a certain degree of macroscopic damage; Pre-destruction period: that is, the later stage of the accelerated increase of acoustic emission. In this stage, the force on the rock mass exceeds its own strength and destruction may occur at any time.

[0009] In the step 3, a microseismic monitoring system scheme for the mining area is designed according to the monitoring scope of the mine; the entire microseismic monitoring system includes an underground microseismic data acquisition station and a ground pressure monitoring station in the surface office area; the signals monitored by the sensor are transmitted to each horizontal data acquisition station via a signal cable; the data acquisition station transmits the microseismic signal data to the ground pressure monitoring station in the office area via an optical cable; the main server of the monitoring system is arranged in the ground pressure monitoring station in the office building, and the main server of the entire system realizes synchronous timing of each acquisition instrument through GPS; and through the Internet, the monitoring system realizes remote monitoring function.

[0010] In step 4, the ground pressure microseismic monitoring system is used to analyze the single-channel microseismic data collected in real time, and the change speed of the single-channel event is analyzed against the incubation process of the pillar destruction, and the development stage of the pillar destruction is given, thereby realizing accurate early warning of the pillar destruction in stages; in actual monitoring applications, in order to ensure mine safety, an early warning can generally be issued during the accelerated incubation period of the pillar destruction.

[0011] Advantages of the present invention: The pillar destruction phased early warning method based on microseismic single-channel events of the present invention can realize the full life cycle monitoring of the incubation process of pillar destruction in mines, and provide accurate phased early warning of potential pillar destruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the test system of the present invention.

[0013] Figure 2 It is a schematic diagram of the test loading method of the present invention.

[0014] Figure 3 This is a relationship diagram between the uniaxial compression failure stress of rock and the accumulated acoustic emission of the present invention.

[0015] Figure 4 FIG. 4 is a diagram showing the architecture of the microseismic monitoring system of the present invention.

[0016] Figure 5 It is a curve diagram of the number of trigger events of a single channel of the present invention. DETAILED DESCRIPTION

[0017] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings.

[0018] like Figure 1-5 As shown, the method for early warning of pillar destruction in stages based on microseismic single-channel events of the present invention is characterized by comprising the following steps: Step 1: Conduct a rock acoustic emission characteristic test, conduct a uniaxial compression failure acoustic emission test on the target mine rock, and obtain the acoustic emission characteristics of the pillar failure process; Step 2: Analysis of the whole life cycle of pillar destruction incubation: According to the speed of acoustic emission change during rock destruction, the whole life cycle of pillar destruction incubation is divided into initial incubation period, constant speed incubation period, initial accelerated incubation period, accelerated incubation period and near-destruction period; Step 3: Establish a ground pressure microseismic monitoring system to achieve real-time monitoring of mine pillar damage and obtain the results of single-channel microseismic event changes in real time; Step 4: Early warning analysis of pillar damage in stages: analyze the change rate of single-channel events against the incubation process of pillar damage, and give the development stage of pillar damage, so as to achieve accurate early warning of pillar damage in stages.

[0019] In the step 1, the rock to be tested in the mine is processed into a rectangular specimen with a size of 50 mm×50 mm×100 mm; the loading system adopts a hydraulic universal material testing machine and adopts a stress-controlled loading method; the monitoring system includes an acoustic emission sensor, an acoustic emission preamplifier, an acoustic emission card, an acoustic emission host system and an acoustic emission processing software.

[0020] In the step 2, a uniaxial compression test of rock is carried out using a rock acoustic emission test system. Accompanied by the initiation and expansion of microcracks and the generation of macroscopic damage, a large number of acoustic emission signals are released in the whole process. According to a large number of acoustic emission characteristic results of rock uniaxial compression damage, the acoustic emission events of rock from loading to damage can be roughly divided into four stages: the initial growth stage of OA acoustic emission events, the calm stage of AB acoustic emission, the initial accelerated growth stage of BC acoustic emission events, and the accelerated growth stage of CD acoustic emission events.

[0021] In step 2, during the entire life cycle of the pillar destruction, Initial incubation period: that is, the initial increase stage of acoustic emission, during which the stress on the rock mass begins to increase and the internal discontinuities begin to compact, which will produce more microseismic events; Isokinetic incubation period: that is, the acoustic emission quiet period, during which the stress on the rock mass continues to increase, but still fails to cause a large number of fractures inside the rock mass, and this process will not produce many microseismic events; Initial acceleration incubation period: that is, the initial acceleration increase stage of acoustic emission. During this stage, the force on the rock mass continues to increase, resulting in a certain degree of fracture inside the rock mass. This process will produce more microseismic events; Accelerated incubation period: that is, the stage of accelerated increase of acoustic emission. During this stage, the force on the rock mass is close to its own strength, which will cause a large number of cracks inside the rock mass. This process will produce a large number of microseismic events and a certain degree of macroscopic damage; Pre-destruction period: that is, the later stage of the accelerated increase of acoustic emission. In this stage, the force on the rock mass exceeds its own strength and destruction may occur at any time.

[0022] In the step 3, a microseismic monitoring system scheme for the mining area is designed according to the monitoring scope of the mine; the entire microseismic monitoring system includes an underground microseismic data acquisition station and a ground pressure monitoring station in the surface office area; the signals monitored by the sensor are transmitted to each horizontal data acquisition station through a signal cable; the data acquisition station transmits the microseismic signal data to the ground pressure monitoring station in the office area through an optical cable; the main server (monitoring and analysis system) of the monitoring system is arranged in the ground pressure monitoring station in the office building, and the main server of the entire system realizes synchronous timing of each acquisition instrument through GPS; and through the Internet, the monitoring system realizes remote monitoring function.

[0023] In step 4, the ground pressure microseismic monitoring system is used to analyze the single-channel microseismic data collected in real time, and the change speed of the single-channel event is analyzed against the incubation process of the pillar destruction, and the development stage of the pillar destruction is given, thereby realizing accurate early warning of the pillar destruction in stages; in actual monitoring applications, in order to ensure mine safety, an early warning can generally be issued during the accelerated incubation period of the pillar destruction.

[0024] The following is an example of monitoring and early warning analysis of a certain mine pillar damage. Figure 5 This is the change curve of the number of microseismic single-channel events. There were a small number of microseismic events in the nearly 5 months from April 28 to September 18, 2020, and the number of events was generally 1 to 20 per day, with the characteristics of long duration and small number of events; the 8 months from September 19, 2020 to May 12, 2021 were a relatively quiet period, with almost 0 events per day, and occasionally 1 to 2 events; in the month from May 13 to June 16, 2021, the number of events per day was 2 to 12, with an average of 3.6 per day, characterized by short time and rapid growth; in the nearly 2 months from June 17 to August 10, 2021, the number of events per day was 2 to 54, with an average of 16.9 per day, characterized by long time and extremely rapid growth. An early warning message was issued during this stage, and longitudinal cracks occurred in the pillar where the sensor was located on July 19, 2021.

Claims

1. A phased early warning method for pillar damage based on microseismic single-channel events, characterized in that: The steps include: Step 1: Conduct a rock acoustic emission characteristic test, conduct a uniaxial compression failure acoustic emission test on the target mine rock, and obtain the acoustic emission characteristics of the pillar failure process; Step 2: Analysis of the whole life cycle of pillar destruction incubation: According to the speed of acoustic emission change during rock destruction, the whole life cycle of pillar destruction incubation is divided into initial incubation period, constant speed incubation period, initial accelerated incubation period, accelerated incubation period and near-destruction period; Step 3: Establish a ground pressure microseismic monitoring system to achieve real-time monitoring of mine pillar damage disasters and obtain the results of single-channel microseismic event changes in real time; Step 4: Early warning analysis of pillar damage in stages: analyze the change rate of single-channel events against the incubation process of pillar damage, and give the development stage of pillar damage, so as to achieve accurate early warning of pillar damage in stages.

2. The method for early warning of pillar damage in stages based on microseismic single-channel events according to claim 1 is characterized in that: In the step 1, the rock to be tested in the mine is processed into a cuboid sample; the loading system adopts a hydraulic universal material testing machine and adopts a stress-controlled loading method; the monitoring system includes an acoustic emission sensor, an acoustic emission preamplifier, an acoustic emission card, an acoustic emission host system and an acoustic emission processing software.

3. The method for early warning of pillar damage in stages based on microseismic single-channel events according to claim 1 is characterized in that: In the step 2, a uniaxial compression test of rock is carried out using a rock acoustic emission test system. Accompanied by the initiation and expansion of microcracks and the generation of macroscopic damage, a large number of acoustic emission signals are released in the whole process. According to a large number of acoustic emission characteristic results of rock uniaxial compression damage, the acoustic emission events of rock from loading to damage can be roughly divided into four stages: the initial growth stage of OA acoustic emission events, the calm stage of AB acoustic emission, the initial accelerated growth stage of BC acoustic emission events, and the accelerated growth stage of CD acoustic emission events.

4. The method for early warning of pillar damage in stages based on microseismic single-channel events according to claim 1 is characterized in that: In step 2, during the entire life cycle of the pillar destruction, Initial incubation period: that is, the initial increase stage of acoustic emission, during which the stress on the rock mass begins to increase and the internal discontinuities begin to compact, which will produce more microseismic events; Isokinetic incubation period: that is, the acoustic emission quiet period, during which the stress on the rock mass continues to increase, but still fails to cause a large number of fractures inside the rock mass, and this process will not produce many microseismic events; Initial acceleration incubation period: that is, the initial acceleration increase stage of acoustic emission. During this stage, the force on the rock mass continues to increase, resulting in a certain degree of fracture inside the rock mass. This process will produce more microseismic events; Accelerated incubation period: that is, the stage of accelerated increase of acoustic emission. During this stage, the force on the rock mass is close to its own strength, which will cause a large number of cracks inside the rock mass. This process will produce a large number of microseismic events and a certain degree of macroscopic damage; Pre-destruction period: that is, the later stage of the accelerated increase of acoustic emission. In this stage, the force on the rock mass exceeds its own strength and destruction may occur at any time.

5. The method for early warning of pillar damage in stages based on microseismic single-channel events according to claim 1 is characterized in that: In the step 3, a microseismic monitoring system scheme for the mining area is designed according to the monitoring scope of the mine; the entire microseismic monitoring system includes an underground microseismic data acquisition station and a ground pressure monitoring station in the surface office area; the signals monitored by the sensor are transmitted to each horizontal data acquisition station through a signal cable; The data collection site transmits the microseismic signal data to the ground pressure monitoring station in the office area via optical cables; the main server of the monitoring system is arranged in the ground pressure monitoring station in the office building, and the main server of the entire system uses GPS to synchronize the timing of each data collector; and through the Internet, the monitoring system realizes long-distance monitoring function.

6. The method for early warning of pillar damage in stages based on microseismic single-channel events according to claim 1 is characterized in that: In step 4, the ground pressure microseismic monitoring system is used to analyze the single-channel microseismic data collected in real time, and the change speed of the single-channel event is analyzed against the incubation process of the pillar destruction, and the development stage of the pillar destruction is given, thereby realizing accurate early warning of the pillar destruction in stages; in actual monitoring applications, in order to ensure mine safety, an early warning can generally be issued during the accelerated incubation period of the pillar destruction.

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