Rockburst monitoring system and data acquisition and processing method based on distributed optical fiber sensing

Abstract

The invention discloses a rock burst monitoring system based on distributed optical fiber sensing and a data acquisition and processing method. A plurality of monitoring armored optical cables are installed and fixed along the top and supporting rock masses or supporting walls on both sides of a tunnel being excavated or completed, or on a working surface being excavated along a mountain or ore body; one end of the plurality of monitoring armored optical cables is connected to a multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, and the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system is connected to a real-time data recording and processing computer. When strain, displacement, rupture and a large number of microseismic events are induced in a local area of ​​the monitored tunnel or working surface due to underground stress accumulation and concentration, strain and displacement will be generated in the corresponding local area on the monitoring armored optical cable at the same time. The strain, displacement and microseismic events measured and monitored in real time are used to warn or process or reinforce the local area on the monitored rock mass where rock burst may occur in advance.

Description

Technical Field

[0001] The present invention relates to the field of geophysical exploration technology, and in particular to a rockburst monitoring system based on distributed optical fiber sensing and a data acquisition and processing method. Background Art

[0002] Rockburst, also known as rock burst, is a phenomenon in which the elastic deformation energy accumulated in the rock mass is suddenly and violently released under certain conditions, causing the rock to burst and eject. The main reason for rockburst is that the surrounding rock strength cannot adapt to the concentrated excessive stress and suddenly loses stability. Rockburst is one of the main safety hazards faced by tunnels and deep mines. Minor rockbursts only cause rock flakes to fall off without ejection. Severe rockbursts can measure a magnitude of 4.6 and an intensity of 7 to 8 degrees, causing damage to ground buildings and accompanied by a loud noise. Rockbursts can occur suddenly or last for several days to several months. The condition for rockburst is that there is a high ground stress in the rock mass, which exceeds the strength of the rock itself, and the rock has a high degree of brittleness and elasticity. Under such conditions, once the underground engineering activities destroy the original equilibrium state of the rock mass, the release of energy accumulated in the rock mass will cause rock destruction and eject the broken rock.

[0003] Rockbursts in tunnels and deep mines are common dynamic failure phenomena in the construction process of deep underground projects. When the high elastic strain energy accumulated in the rock mass is greater than the energy consumed by rock failure, the balance of the rock mass structure is destroyed. The excess energy causes rock bursting, and rock fragments are peeled off and collapsed from the rock mass. Rockbursts in tunnels and deep mines are failure phenomena such as rock fragmentation, ejection, and even earthquakes caused by the sudden release of elastic deformation energy caused by excavation of brittle rocks under high stress. Its mechanical mechanism is relatively complex, and the current research on it is still at the hypothesis and experience stage. As a dynamic instability phenomenon induced by multi-factor coupling, the complexity of the rockburst formation mechanism and the imperfection of related theories make the actual application effect of rockburst prediction theory less than ideal. So far, there is no mature theory and method in China. In recent years, more and more rockburst problems have emerged. Rockbursts not only damage production equipment and delay construction period, but also seriously threaten the personal safety of construction workers. It has become a major technical obstacle in the future construction of deep underground projects in my country.

[0004] Rockbursts often cause serious damage to the excavation face, equipment damage and casualties, and have become a global problem in the field of rock underground engineering and rock mechanics. Minor rockbursts only cause rock flakes to fall off without ejection. Severe rockbursts can measure a magnitude of 4.6, which generally lasts for several days or months. The reason for rockbursts is that there is a high ground stress in the rock mass, which exceeds the strength of the rock itself. At the same time, the rock has a high degree of brittleness and elasticity. At this time, once the underground engineering destroys the balance of the rock mass, the powerful energy destroys the rock and throws out the broken rock. The methods to prevent rockbursts are stress relief, water injection softening and the use of anchor bolts-wire mesh-concrete support.

[0005] The conditions for rock bursts are: (1) recent tectonic activities have caused high stress in deep mineral rocks, and a large amount of strain energy is stored in the rock mass. When this part of energy exceeds the strength of the rock itself, a rock burst will occur;

[0006] (2) The surrounding rock is hard, fresh and complete, with few or only hidden cracks, and has high brittleness and elasticity. It can store energy, and its deformation characteristics belong to the brittle failure type. When the stress is relieved by engineering excavation, the rebound deformation is very small, which is very likely to cause the rock to burst and pop out;

[0007] (3) If there is less groundwater and the rock mass is dry, rock bursts are also likely to occur;

[0008] (4) Underground projects with irregular excavation sections, large cavern groups with many branch tunnels, or areas where local stress concentration occurs due to cross-sectional changes are areas where rock bursts are prone to occur.

[0009] Deep mine rock burst has the following characteristics:

[0010] (1) Suddenness: There are no obvious signs before the incident occurs, and even no sound may be heard. Places where it is generally believed that rocks will not fall may suddenly cause rocks to burst. Sometimes the rocks fall down in response to the sound, and sometimes they do not fall for the time being.

[0011] (2) Location Concentration: Although there are some individual cases where the rockburst occurs far from the newly excavated T-face, most of them occur near the newly excavated working face. The most common rockburst locations are the arch or arch waist.

[0012] (3) Time concentration and continuity: Rock bursts occur successively after blasting or excavation, usually within 24 hours after blasting, and usually last for 1 to 2 months, and sometimes for more than 1 year. There are usually no obvious signs beforehand.

[0013] (4) Ejection: During a rockburst, rock blocks are ejected from the surrounding rock matrix of the cave wall, generally in the form of irregular flakes with thick middle and thin edges.

[0014] Rockburst is one of the major disasters threatening mine safety production. Its manifestation is sudden and disastrous, but its accumulation process is spatial and temporal. Therefore, on the basis of a deep understanding of the mechanism of rockburst, it is necessary to predict the spatial position and time effect of rockburst and take effective prevention and control measures to avoid and reduce the losses caused by rockburst.

[0015] In the existing technology, the rockburst monitoring system can generally monitor the following: (1) convergence rate monitoring; (2) seismic activity monitoring; (3) microseismic activity monitoring; (4) rock stress measurement. The current more feasible solution for rockburst monitoring and early warning is multi-technology integration. The feasible specific technologies are as follows: 1. Ground stress testing: hollow inclusions; 2. Rapid acquisition of tunnel surrounding rock structure parameters: three-dimensional photogrammetry and rock structure analysis; 3. Changes in the three-dimensional stress field of tunnel surrounding rock: high-precision three-axis borehole strain gauges; 4. Passive and active microseismic high-precision monitoring; rockburst is a special earthquake, and quantitative seismology and engineering seismology are used to achieve rockburst monitoring and early warning; 5. On-site rapid testing of rock physical and mechanical parameters, borehole television, etc.; 6. Rockburst risk management software and rockburst control technology.

[0016] At present, the mainstream rock burst activity is to observe the law of rock burst activity through microseismic monitoring technology. Although there are no obvious signs before the rock burst occurs, technicians have found through detailed observation that the general rock burst occurs mainly 2 to 6 hours after the explosion. In recent years, microseismic monitoring has developed rapidly as an effective method for locating and monitoring the strength of rock mass fractures in three-dimensional space. Microseismic monitoring technology can analyze the time, location and magnitude (also known as the three elements of time and space) of the source damage event through sound waves, thus providing potential possibilities for rock burst prediction. The microseismic monitoring system with higher sensitivity can capture rock microfracture precursor events with smaller magnitude than rock burst.

[0017] The disadvantage of the existing technology is that almost all rockburst monitoring technologies and methods rely on various sensors sparsely arranged in the tunnel or on the working surface to measure various rock mechanical parameters and local volume change characteristics of the rock mass in real time, and monitor or predict the possibility of rockburst through the results of data calculation and processing. This method of monitoring the possibility of rockburst along the entire tunnel or the entire mining working surface through sparsely arranged sensors is inaccurate and imperfect. It is difficult to accurately determine the specific location or section where rockburst may occur through the processing of monitoring data, and it is also difficult to effectively reinforce or otherwise treat the specific location or section where rockburst may occur.

[0018] For example, the rockburst microseismic monitoring technology currently in common use is a method and means to monitor microseismic events that occur before a rockburst occurs, relying only on a small number of conventional geophones sparsely distributed in the monitored area. However, the microseismic monitoring technology cannot accurately measure the slow strain and displacement caused by underground stress concentration and accumulation on the tunnel top and the supporting rock mass on both sides or the mountain or ore body excavation working surface, but can only record the microseismic events with large energy induced when the rock mass breaks. Although the microseismic events monitored in the area or section where a rockburst is about to occur are directly related to the rockburst, this kind of microseismic monitoring results close to the rockburst cannot provide sufficient warning time for the construction personnel, nor can they take timely treatment or reinforcement measures for the dangerous parts or sections of the monitored rock mass before the rockburst occurs. In addition, due to the use of a limited number of geophones in the rockburst microseismic monitoring system, the amount of microseismic data recorded is small, and the processing results have low accuracy in locating the microseismic events and estimating the energy intensity, making it difficult to accurately predict the specific location and possible time of the rockburst. Summary of the invention

[0019] In order to solve the problems existing in the prior art, the present invention discloses a rockburst monitoring system and a data acquisition and processing method based on distributed optical fiber sensing, which solves the problem that the previous methods and means of measuring and monitoring the mechanical parameters of the rock mass before the rockburst only rely on a small number of sparsely distributed various sensors, or using a limited number of conventional geophones to monitor the microseismic events that occur before the rockburst, cannot accurately measure the slow strain and displacement caused by the concentration and accumulation of underground stress on the tunnel top and the supporting rock mass on both sides or the mountain or ore body excavation working surface, but can only record the energy-intensive microseismic events induced by the rock mass when it breaks. Although the microseismic events monitored in the area or section of the rock mass where the rockburst is about to occur are directly related to the rockburst, the monitoring results of the microseismic events near the rockburst cannot provide sufficient warning time for the construction personnel, and there is no time to timely handle or reinforce the dangerous parts or sections of the monitored rock mass before the rockburst occurs.

[0020] The present invention provides a rockburst monitoring system and a data acquisition and processing method based on distributed optical fiber sensing. The technical solution adopted by the present invention is:

[0021] The rockburst monitoring system based on distributed optical fiber sensing comprises a plurality of monitoring armored optical cables, a multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, and a real-time data recording, storage and processing computer system. The plurality of monitoring armored optical cables are installed and fixed along the top and supporting rock masses or supporting walls on both sides of a tunnel that is being excavated or driven or has been completed, or on a working surface along the excavation or digging of a mountain or ore body; one end of the plurality of monitoring armored optical cables is connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, and the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system is connected to the real-time data recording, storage and processing computer system.

[0022] Wherein, the monitoring armored optical cables are all armored optical cables wound in a spiral shape.

[0023] The plurality of monitoring armored optical cables are parallel to the extension direction of the tunnel or the deployment direction of the working surface.

[0024] The distance between adjacent monitoring armored optical cables shall not exceed 1 meter; the length of each monitoring armored optical cable shall cover the entire length of the tunnel or the entire length of the working surface.

[0025] The monitoring armored optical cable is fixed with cement or nails, fixed on the tunnel top and supporting rock masses or supporting walls on both sides, or fixed on the working surface.

[0026] The other end of all monitoring armored optical cables is provided with a light-extinguishing device, which is a light-extinguishing device installed at the tail end of the monitoring armored optical cable, or a fiber tail end is knotted to eliminate the strong reflection signal of the fiber at the tail end.

[0027] The data acquisition and processing method of the rockburst monitoring system based on distributed optical fiber sensing comprises the following steps:

[0028] S1: The monitoring armored optical cable is fixed on the monitored rock mass with cement or nails and connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system. The multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system is started to continuously measure and record the phase change information of the backscattered Rayleigh light transmitted from each monitoring armored optical cable to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system;

[0029] S2: Compare and analyze the phase data of the backscattered Rayleigh light recorded in each measurement with the phase data of the backscattered Rayleigh light recorded previously;

[0030] S3: When the phase data of the backscattered Rayleigh light recorded in two measurements differ or change at a certain position of the monitoring armored optical cable, the phase difference or change data is converted into the strain or displacement data of the optical fiber through the built-in phase data processing software in the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, and then the strain or displacement data detected by the monitoring armored optical cable is transmitted to the real-time data recording and processing computer system at the monitoring site;

[0031] S4: After receiving the strain or displacement data along each monitoring armored optical cable transmitted from the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, the real-time data recording and processing computer system projects the rock mass strain or displacement data on each monitoring armored optical cable onto the plane layout diagram of the rock mass monitored according to its actual layout position through real-time calculation and statistical analysis;

[0032] S5: The time differential (first-order derivative) of the rock mass strain data on each monitoring armored optical cable is obtained to obtain the rate of change of the rock mass strain data on each monitoring armored optical cable over time, and the rate of change of the rock mass strain data on each monitoring armored optical cable over time is projected onto the plane layout diagram of the rock mass monitored by it according to its actual layout position;

[0033] S6: Before a rockburst occurs in a part of the monitored rock mass, the rock mass in a part or section will begin to crack or break due to the accumulation and concentration of underground stress in the rock mass, thereby inducing microseismic events distributed along the range of the rock mass. At this time, the monitoring armored optical cable laid along the monitored rock mass can monitor and record the seismic wave signals of these microseismic events through a multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system, and transmit the recorded microseismic data to the real-time data recording and processing computer system at the monitoring site in real time.

[0034] S7: The real-time data recording and processing computer system at the monitoring site can calculate the location coordinates of the specific rupture point on the rock mass that induced the microseismic event and the time of occurrence of the microseismic event through inversion according to the difference in the travel time of the longitudinal and transverse waves of the detected microseismic event signals reaching the detection points distributed on the monitoring armored optical cable, the coordinate position of each detection point and the longitudinal and transverse wave velocities of the monitored rock mass. The amplitude (amplitude) of the recorded microseismic event signal can also be used to calculate the size of the rock mass rupture or the energy of the microseismic event induced by it;

[0035] S8: The strain, strain rate, slow displacement and distribution position and energy size of the rock mass along the monitoring line or surface of the armored optical cable are displayed in real time on the screen of the real-time data recording and processing computer system at the monitoring site;

[0036] S9: Based on the relatively concentrated distribution of large-scale strains, rapid strain rates, slow displacement superposition and microseismic events that occur locally in the monitored rock mass along the monitoring armored optical cable, and the trend of gradually increasing energy, the local locations or specific sections or intervals of the rock mass where rock bursts may occur are delineated, and early warning information or forecasts are issued in time, and the local locations or specific sections of the rock mass where rock bursts may occur are immediately processed or reinforced in advance.

[0037] The present invention can measure and monitor in real time the strain, displacement, fracture and induced microseismic events occurring locally on the tunnel top and supporting rock masses on both sides or on the mountain or ore body excavation working surface, and give early warning or carry out advance processing or reinforcement of the local location or specific section of rock burst that may occur on the monitored rock mass. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the deployment of the monitoring armored optical cable on the tunnel rock mass according to the present invention.

[0039] Figure 2 This is a schematic diagram of the deployment of the monitoring armored optical cable of the present invention on a mountain excavation working surface. DETAILED DESCRIPTION

[0040] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0041] A rockburst monitoring system based on distributed optical fiber sensing, comprising a plurality of monitoring armored optical cables 2, a multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, and a real-time data recording, storage and processing computer system 5;

[0042] like Figure 1 The monitoring armored optical cable 2 is installed and fixed along the top and supporting rock masses or supporting walls on both sides of the tunnel 1 that is being excavated or driven or has been completed;

[0043] Or Figure 2 As shown, it is installed and fixed on the working surface 7 along the excavation or digging of the mountain or ore body 6;

[0044] The real-time data recording, storage and processing computer system 5 is connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, and is used for real-time data recording, storage, processing and display of the strain, strain rate, displacement superposition and microseismic events and energy of the rock mass along the monitoring armored optical cable monitoring line or monitoring surface.

[0045] The monitoring armored optical cables 2 are all armored optical cables wound in a spiral shape.

[0046] Each monitoring armored optical cable 2 is parallel to the extension direction of the tunnel 1 or the deployment direction of the working surface 7;

[0047] The distance between adjacent monitoring armored optical cables 2 does not exceed 1 meter; the length of each monitoring armored optical cable 2 covers the length of the entire tunnel 1 or the length of the entire working surface 7.

[0048] First, along the extension direction of the supporting rock or supporting wall at the top and both sides of the tunnel 1, or along the extension direction of the working surface 7, shallow trenches parallel to each other are dug according to the pre-set conditions. The shallow trenches are 2 cm wide and 5 cm deep, and the monitoring armored optical cable 2 is placed in the shallow trenches. The monitoring armored optical cable 2 is then fixed to the tunnel 1 or the working surface 7 with cement. The monitoring armored optical cable 2 can also be fixed to the tunnel 1 or the working surface 7 with densely distributed metal staples, so that the monitoring armored optical cable 2 has a very good wall coupling with the monitored rock or wall. When the ground stress accumulates and concentrates in local positions or specific sections on the top and supporting rock masses or supporting walls of the tunnel 1 or on the working surface 7, causing rock mass strain, deformation, displacement, rupture and a large number of induced microseismic events, the monitoring armored optical cable 2, which is closely coupled with the rock mass, will also be stretched or compressed to produce strain and deformation along with the strain, deformation, displacement, rupture and a large number of induced microseismic events of the rock mass. At this time, the phase of the back-scattered Rayleigh light at the part where the optical fiber in the monitoring armored optical cable 2 produces tensile or compressive strain and deformation will change along with the stretching or compression of the optical fiber, and the multi-channel broadband distribution cable 2 connected at the head end of the monitoring armored optical cable 2 will be connected to the monitoring armored optical cable 2. The distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, through the computer system 5 for real-time data recording, storage, processing and display and the data processing and interpretation software system, can calculate the strain, deformation, displacement and rupture size of the rock mass along the monitoring line or monitoring surface of the monitoring armored optical cable 2 according to the size of the phase change, as well as the number, distribution position range and energy of microseismic events, and can easily determine the specific and accurate location of the optical fiber strain and deformation, that is, the location or section where the rock mass strain, deformation, displacement, rupture and microseismic events occur according to the arrival time of the back Rayleigh scattered light and the propagation speed of light in the optical fiber.

[0049] After all the monitoring armored optical cables 2 are installed and fixed with cement or staples at equal intervals along the extension direction of the tunnel 1 or the layout direction of the working surface 7, a special technical treatment is performed on the tail end of the monitoring armored optical cable 2, such as installing a light extinguisher or tying a knot on the optical fiber to eliminate the strong reflection signal of the optical fiber at the tail end. Finally, the head end of the monitoring armored optical cable 2 is directly connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4; the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4 is connected to the real-time data recording, storage and processing computer system 5 at the monitoring site, and real-time display of slow strain, superimposed displacement and micro-seismic event position and energy of the rock mass along the monitoring line of the monitoring armored optical cable 2 or the monitoring excavation working surface, so as to provide real-time rock burst risk monitoring and early warning information for the tunnel or mountain or ore construction site.

[0050] The data acquisition and processing method of the rockburst monitoring system based on distributed optical fiber sensing comprises the following steps:

[0051] S1: The monitoring armored optical cable 2 is fixed on the monitored rock mass with cement or nails and connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, and the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4 is started to continuously measure and record the phase change information of the backscattered Rayleigh light transmitted from each monitoring armored optical cable 2 to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4;

[0052] S2: Compare and analyze the phase data of the backscattered Rayleigh light recorded in each measurement with the phase data of the backscattered Rayleigh light recorded previously;

[0053] S3: When the phase data of the backscattered Rayleigh light recorded in two measurements differ or change at a certain position of the monitoring armored optical cable, the phase difference or change data is converted into the strain or displacement data of the optical fiber through the built-in phase data processing software in the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, and then the strain or displacement data detected by the monitoring armored optical cable 2 is transmitted to the real-time data recording, storage and processing computer system 5 at the monitoring site;

[0054] S4: After receiving the strain or displacement data along each monitoring armored optical cable 2 transmitted from the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, the real-time data recording, storage and processing computer system 5 projects the rock mass strain or displacement data on each monitoring armored optical cable 2 onto the plane layout diagram of the monitored rock mass according to its actual layout position through real-time calculation and statistical analysis;

[0055] S5: Calculate the time differential (first-order derivative) of the rock mass strain data on each monitoring armored optical cable 2 to obtain the rate of change of the rock mass strain data on each monitoring armored optical cable 2 over time, and project the rate of change of the rock mass strain data on each monitoring armored optical cable 2 over time onto the plane layout diagram of the rock mass monitored by it according to its actual layout position;

[0056] S6: Before a rock burst occurs in a part of the monitored rock mass, the part or section of the monitored rock mass will begin to crack or break due to the accumulation and concentration of underground stress in the rock mass, thereby inducing microseismic events distributed along the range of the rock burst. At this time, the monitoring armored optical cable 2 arranged along the monitored rock mass can monitor and record the seismic wave signals of these microseismic events through the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system 4, and transmit the recorded microseismic data to the real-time data recording, storage and processing computer system 5 at the monitoring site in real time;

[0057] S7: The real-time data recording, storage and processing computer system 5 at the monitoring site can calculate the location coordinates of the specific rupture point on the rock mass that induced the microseismic event and the time of occurrence of the microseismic event through inversion according to the difference in the longitudinal and transverse travel time of the detected microseismic event signal reaching the detection points distributed on the monitoring armored optical cable 2, the coordinate position of each detection point and the longitudinal and transverse wave speeds of the monitored rock mass. The magnitude of the rock mass rupture or the energy of the microseismic event induced by it can also be calculated through the amplitude (amplitude) of the recorded microseismic event signal;

[0058] S8: Displaying the strain, strain rate, slow displacement and distribution position and energy size of the rock mass along the monitoring line or monitoring surface of the armored optical cable 2 in real time on the screen of the real-time data recording, storage and processing computer system 5 at the monitoring site;

[0059] S9: Based on the relatively concentrated distribution of large-scale strains, rapid strain rates, slow displacement superposition and microseismic events that occur locally in the monitored rock mass along the monitoring armored optical cable 2 and the trend of gradually increasing energy, the local positions or specific sections or intervals of the rock mass where rock burst may occur are circled, and early warning information or forecasts are issued in time, and the local positions or specific sections of the rock mass where rock burst may occur are immediately processed or reinforced in advance.

Claims

1. The rockburst monitoring system based on distributed optical fiber sensing is characterized by: The invention comprises a plurality of monitoring armored optical cables (2), a multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4), and a real-time data recording, storage and processing computer system (5). The plurality of monitoring armored optical cables (2) are installed and fixed along the top and supporting rock mass or supporting wall on both sides of a tunnel (1) being excavated or driven or completed, or on an excavated or driven working face (7) along a mountain or ore body (6); one end of the plurality of monitoring armored optical cables (2) is connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4), and the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4) is connected to the real-time data recording, storage and processing computer system (5); The monitoring armored optical cables (2) are all armored optical cables wound in a spiral shape; The plurality of monitoring armored optical cables (2) are parallel to the extension direction of the tunnel (1) or the deployment direction of the working surface (7); The distance between adjacent monitoring armored optical cables (2) does not exceed 1 meter; the length of each monitoring armored optical cable (2) covers the length of the entire tunnel (1) or the length of the entire working surface (7); The monitoring armored optical cable (2) is fixed with cement or nails to the top of the tunnel (1) and the supporting rock mass or supporting walls on both sides, or to the working surface (7); The other end, i.e. the tail end, of the monitoring armored optical cable (2) is provided with a light-extinguishing device; The extinction device is a de-optical device installed at the tail end of the monitoring armored optical cable (2), or a knot is tied at the tail end of the optical fiber to eliminate the strong reflection signal of the optical fiber at the tail end.

2. The data acquisition and processing method of the rockburst monitoring system based on distributed optical fiber sensing according to claim 1 is characterized in that: The following steps are involved: S1: The monitoring armored optical cable (2) is fixed on the monitored rock mass with cement or staples and connected to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4), and the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4) is started to continuously measure and record the phase change information of the backscattered Rayleigh light transmitted from each monitoring armored optical cable (2) to the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4); S2: Compare and analyze the phase data of the backscattered Rayleigh light recorded in each measurement with the phase data of the backscattered Rayleigh light recorded previously; S3: When the phase data of the backscattered Rayleigh light recorded in two measurements differ or change at a certain position of the monitoring armored optical cable, the phase difference or change data is converted into the strain or displacement data of the optical fiber through the built-in phase data processing software in the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4), and then the strain or displacement data detected by the monitoring armored optical cable (2) is transmitted to the real-time data recording, storage and processing computer system (5) at the monitoring site; S4: After receiving the strain or displacement data along each monitoring armored optical cable (2) transmitted from the multi-channel broadband distributed optical fiber acoustic wave and strain sensing modulation and demodulation system (4), the real-time data recording, storage and processing computer system (5) projects the rock mass strain or displacement data on each monitoring armored optical cable (2) onto the plane layout diagram of the monitored rock mass according to its actual layout position through real-time calculation and statistical analysis; S5: taking the time differential of the rock mass strain data on each monitoring armored optical cable (2) to obtain the change rate of the rock mass strain data on each monitoring armored optical cable (2) over time, and projecting the change rate of the rock mass strain data on each monitoring armored optical cable (2) over time onto the plane layout diagram of the rock mass monitored by the monitoring armored optical cable according to its actual layout position; S6: Before a rock burst occurs in a part of the monitored rock mass, due to the accumulation and concentration of underground stress in the part or section of the rock mass, the part or section of the monitored rock mass will begin to crack or break, thereby inducing microseismic events distributed along the rock burst or section. At this time, the monitoring armored optical cable (2) arranged along the monitored rock mass can monitor and record the seismic wave signals of these microseismic events through the multi-channel broadband distributed optical fiber acoustic wave and strain sensor modulation and demodulation system (4), and transmit the recorded microseismic data to the real-time data recording, storage and processing computer system (5) at the monitoring site in real time. S7: The real-time data recording, storage and processing computer system (5) at the monitoring site can calculate the location coordinates of the specific rupture point on the rock mass that induced the microseismic event and the time when the microseismic event occurred based on the difference in the longitudinal and transverse travel time of the detected microseismic event signal reaching the detection points distributed on the monitoring armored optical cable (2), the coordinate position of each detection point and the longitudinal and transverse wave velocities of the monitored rock mass through inversion. The size of the rock mass rupture or the energy of the microseismic event induced by the recorded microseismic event signal can also be calculated. S8: Displaying the strain, strain rate, slow displacement and distribution position and energy size of the rock mass along the monitoring line or surface of the monitoring armored optical cable (2) on the screen of the real-time data recording, storage and processing computer system (5) at the monitoring site in real time; S9: Based on the results of the superposition of large-scale strain, rapid strain rate, slow displacement, and the relatively concentrated distribution of microseismic events and the trend of gradually increasing energy, the local location or specific section or interval of the rock mass where rock burst may occur is delineated, and early warning information or forecast is issued in time, so that the local location or specific section of the rock mass where rock burst may occur is immediately processed or reinforced in advance.

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