Deep-buried long-distance TBM tunnel fracture type rockburst micro-seismic monitoring method

Abstract

The invention discloses a deep-buried long-distance TBM tunnel fracture type rockburst micro-seismic monitoring method. A micro-seismic system is installed on a TBM; the micro-seismic system is in communication connection with a data memory and a monitoring control center through a local area network in the tunnel; the micro-seismic monitoring method comprises the following steps: uploading collected micro-seismic data to a data memory outside a tunnel through a local area network by virtue of a micro-seismic system, and synchronously downloading the data in the data memory by virtue of a monitoring control center, so as to obtain a specific intersection position of a fractured rock mass and an unexcavated rock mass by analyzing spatial distribution characteristics of the micro-seismic data. According to the micro-seismic monitoring method disclosed by the invention, the collected data in the tunnel is timely transmitted to the outside of the tunnel based on the local area network and the data memory, so that the timeliness of processing and analyzing the data by the monitoring center outside the tunnel is ensured, and the problem that the rockburst monitoring data of the deeply-buried long-distance TBM tunnel is difficult to timely acquire is solved; the original monitoring data is stored in the data memory, so that the problems of data damage, data loss and the like caused by power failure are avoided, and the continuity of rockburst micro-seismic monitoring is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of microseismic monitoring, and particularly to a microseismic monitoring method for fracture-type rockburst in a deep-buried long-distance TBM tunnel. Background Art

[0002] According to the breeding mechanism of rockburst, rockburst can be classified into strain-type rockburst, strain-joint slip-type rockburst, and fracture-type rockburst. Fracture-type rockburst is caused by the sudden relative sliding of fractures induced by construction activities and the release of a large amount of energy. Compared with strain-type and strain-joint slip-type rockbursts, fracture-type rockburst has a larger influence area and stronger destructive power, and may even induce continuous strong rockbursts, with magnitudes reaching earthquake levels, seriously endangering the safety of construction workers.

[0003] The microseismic monitoring technology is to use multiple sensors to collect rock mass microcrack signals, and through signal analysis technology and seismic source inversion methods, find the effective rock mass microcrack signals among numerous signals, obtain the occurrence time, location, and nature of rock mass microcracks, and then infer the development trend of rock fractures based on microseismic source parameters, concentration degree, and fracture density, so as to realize the evaluation and monitoring of rockburst. Rock mass microseismic signals are the most intuitive manifestation of rock mass microcracks, so microseismic monitoring is the most direct and effective means to monitor the process of rock mass fracture and the process of rockburst breeding.

[0004] The microseismic monitoring method has an important impact on the ability to capture rock mass microcracks, and thus affects the rockburst early warning effect. So far, no microseismic monitoring method for long-distance tunnel fracture-type rockburst has been seen. Research results on tunnel microseismic monitoring methods, such as the invention titled "A full-fiber microseismic monitoring device and monitoring method", application number 202411487254.0; the invention titled "A method for arranging microseismic monitoring sensors in a tunnel project with inclined strata", application number 202010149542.0; the invention titled "A microseismic monitoring method for rockburst in a long-distance TBM tunnel under the geological condition of interbedded hard and soft rocks", application number 201811158435.3; the invention titled "An installation device and usage method of a microseismic monitoring sensor based on a bolt", application number 201910833937.X. The above results have optimized and invented the microseismic sensor layout method and rockburst monitoring method, but have not established a corresponding microseismic monitoring method for a specific rockburst type - fracture-type rockburst, and have not considered the influence of fractures on the rockburst monitoring effect; in addition, in a deep-buried long-distance TBM tunnel, the time for personnel to travel between the ground monitoring center and the TBM is relatively long, resulting in the inability to obtain in-tunnel monitoring data in a timely manner, affecting the timeliness of fracture-type rockburst risk prediction.

[0005] Therefore, based on the above technical problems, those skilled in the art urgently need to develop a microseismic monitoring method for fracture-type rockburst in a deep-buried long-distance TBM tunnel. Summary of the Invention

[0006] The object of the present invention is to provide a microseismic monitoring method for fractured rockburst in deep-buried long-distance TBM tunnels, which is used to solve the above-mentioned defects and problems and improve the monitoring ability of fractured rockburst.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A microseismic monitoring method for fractured rockburst in deep-buried long-distance TBM tunnels according to the present invention, which is based on a microseismic system and a plurality of microseismic sensors;

[0009] The microseismic system is installed on the TBM;

[0010] A data storage device and a monitoring control center located outside the tunnel are communicatively connected to the microseismic system through a local area network in the tunnel;

[0011] The microseismic monitoring method uploads the collected microseismic data to the data storage device outside the tunnel through the local area network by the microseismic system, and the monitoring control center synchronously downloads the data in the data storage device, so as to obtain the specific intersection position of the fracture and the unexcavated rock mass by analyzing the spatial distribution characteristics of the microseismic data.

[0012] Further, the microseismic sensors are arranged behind the excavation of the TBM and in the intact rock mass close to the excavation face of the TBM.

[0013] Further, when arranging the microseismic sensors, drill holes in the surrounding rock of the tunnel excavated by the TBM and take pictures to identify the excavation disturbance area;

[0014] The drilling depth exceeds the depth of the excavation disturbance area, and the microseismic sensors are arranged in the drill holes;

[0015] The microseismic system moves along with the TBM.

[0016] Further, the specific intersection position of the fracture and the unexcavated rock mass and the occurrence information of the fracture are obtained by analyzing the spatial distribution characteristics of the microseismic data;

[0017] The driving direction of the tunnel face is judged according to the analysis results.

[0018] Further, the driving direction of the tunnel face is from the hanging wall of the fracture to the footwall of the fracture or from the footwall of the fracture to the hanging wall of the fracture.

[0019] Further, as the tunnel face moves towards the unexcavated rock mass in front of the TBM, the distance between the microseismic sensor and the tunnel face increases. When the distance between the microseismic sensor and the tunnel face reaches the limit monitoring distance of the microseismic sensor, the microseismic sensor is moved into a borehole closer to the tunnel face, and this step is continuously repeated until the tunnel face approaches the intersection position of the fracture and the tunnel.

[0020] Further, it is judged based on the driving direction of the tunnel face;

[0021] When the driving direction of the tunnel face is from the hanging wall of the fracture to the footwall of the fracture, the microseismic sensor is arranged at the hanging wall of the fracture. After the tunnel face exceeds the intersection position of the fracture and the tunnel, the rear microseismic sensor is arranged at the footwall of the fracture again; or

[0022] When the driving direction of the tunnel face is from the footwall of the fracture to the hanging wall of the fracture, the microseismic sensor is arranged at the footwall of the fracture. After the tunnel face exceeds the intersection position of the fracture and the tunnel, the rear microseismic sensor is arranged at the hanging wall of the fracture again.

[0023] In the above technical solution, a microseismic monitoring method for fracture - type rockburst in a deep - buried long - distance TBM tunnel provided by the present invention has the following beneficial effects:

[0024] The microseismic monitoring method of the present invention transmits the data collected in the tunnel to the outside of the tunnel in a timely manner based on a local area network and a data memory, ensuring the timeliness of data processing and analysis by the monitoring center outside the tunnel, solving the problem that it is difficult to obtain the rockburst monitoring data of the deep - buried long - distance TBM tunnel in a timely manner. Storing the original monitoring data in the data memory avoids problems such as data damage and loss caused by power outages, ensuring the continuity of rockburst microseismic monitoring.

[0025] The microseismic monitoring method of the present invention obtains the spatial position relationship between the fracture and the tunnel in the unexcavated area in front of the tunnel face and the fracture occurrence information through the spatial distribution characteristics of microseismic monitoring data, solving the problem that it is difficult to accurately obtain the spatial occurrence position and occurrence information of the fracture, and ensuring the reliability of fracture - type rockburst monitoring.

[0026] The microseismic monitoring method of the present invention arranges microseismic sensors on the hanging wall and the footwall of the fracture respectively, and can accurately, timely and effectively capture the fracture slip signal, solving the problem that it is difficult to accurately capture the microseismic events generated by the fracture slip, and further ensuring the accuracy of fracture - type rockburst monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0028] Figure 1 This is the overall distribution map of microseismic monitoring before excavation to fracture for a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method disclosed in the embodiments of the present application;

[0029] Figure 2 This is the spatial distribution characteristics of microseismic monitoring data for a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method disclosed in the embodiments of the present application Figure 1 ;

[0030] Figure 3 This is the spatial distribution characteristics of microseismic monitoring data for a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method disclosed in the embodiments of the present application Figure 2 ;

[0031] Figure 4 This is the overall layout diagram of microseismic monitoring after excavation to fracture for a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method disclosed in the embodiments of the present application;

[0032] Figure 5 This is the cross-sectional view of the installation layout of microseismic sensors for a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method disclosed in the embodiments of the present application.

[0033] Explanation of reference numerals:

[0034] 1. Excavated tunnel; 2. Driving direction; 3. TBM; 4. Microseismic monitoring system; 5. TBM cutter head; 6. Un-excavated rock mass; 7. Tunnel face; 8. Borehole; 9. Microseismic sensor; 10. Fracture; 11. Monitoring center; 12. Data storage; 13. Local area network; 14. Surrounding rock; 15. Excavation disturbance zone; 16. Microseismic data. Detailed implementation manners

[0035] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] See Figures 1 to 5 as shown;

[0037] This embodiment discloses a buried long-distance TBM tunnel fracture-type rockburst microseismic monitoring method. This microseismic monitoring method is based on the SinoSeiSm (SSS) microseismic system 4 and multiple microseismic sensors 9. The microseismic sensors 9 capture the internal fracture signals of the rock mass and convert them into electrical signals for transmission to the microseismic monitoring system to achieve real-time monitoring of rockbursts;

[0038] The microseismic system 4 is installed on the TBM 3;

[0039] The microseismic system 4 is communicatively connected via a local area network in the tunnel to a data storage 12 and a monitoring and control center 11 located outside the tunnel;

[0040] The microseismic monitoring method uploads the collected microseismic data to the data storage 12 outside the tunnel via the local area network through the microseismic system 4. The data storage 12 is a large-capacity mechanical hard disk. The monitoring and control center 11 synchronously downloads the data in the data storage 12 through data synchronization software. Technical personnel analyze the microseismic data in the monitoring center 12 to obtain the three-dimensional spatial distribution pattern of the microseismic data, so as to obtain the specific intersection position of the fracture 10 and the unexcavated rock mass.

[0041] Specifically, the microseismic monitoring method for deep-buried long-distance TBM tunnel fracture-type rockburst disclosed in this embodiment is mainly based on the microseismic system 4 and microseismic sensors 9. The microseismic system 4 is installed on the TBM 3 and moves along with the movement of the TBM 3. The microseismic system 4 of this embodiment communicates with the data storage 12 and the monitoring and control center 11 outside the tunnel through the local area network, and synchronously uploads the monitoring data to the data storage 12 outside the tunnel in real time. At the same time, the monitoring and control center 11 outside the tunnel synchronously downloads the microseismic data in the data storage 12 through the local area network to realize data transmission and communication for the deep-buried long-distance tunnel. The microseismic sensors 9 of this embodiment are arranged in the intact rock mass behind the excavation of the TBM 3 and close to the excavation face of the TBM 3, and the spatial positions of the microseismic sensors 9 and the fracture 10 are adjusted based on the monitoring data.

[0042] Preferably, the microseismic sensors 9 of this embodiment are arranged behind the excavation of the TBM 3 and in the intact rock mass close to the excavation face of the TBM 3. The boreholes 8 of this embodiment are arranged in the intact rock mass area, and the depth of the boreholes 8 is greater than the depth of the excavation disturbance zone 15.

[0043] More specifically, when arranging the microseismic sensors 9 of this embodiment, boreholes 8 are drilled and photographed at the surrounding rock of the tunnel excavated by the TBM 3 to identify the excavation disturbance zone 15; wherein, the depth of the boreholes 8 of this embodiment exceeds the depth of the excavation disturbance zone 15, and the microseismic sensors 9 are arranged in the boreholes 8; the microseismic system 4 moves along with the movement of the TBM 3.

[0044] Preferably, a three-dimensional spatial distribution map of microseismic events, the tunnel, the fracture, and the unexcavated rock mass is generated based on the microseismic events obtained in real time by the microseismic monitoring system. Based on the occurrence characteristics of the microseismic events distributed along the fracture in the three-dimensional space, the specific intersection position of the fracture and the unexcavated rock mass 6, as well as the attitude information of the fracture 10, are further obtained; the driving direction of the tunnel face 7 is judged according to the relative position of the analysis result and the tunnel face 7.

[0045] Specifically: According to the information obtained from the above analysis of the spatial distribution characteristics of microseismic data, the tunneling direction 2 of the tunnel face 7 in this embodiment is from the hanging wall of the fault 10 to the footwall of the fault 10, or from the footwall of the fault 10 to the hanging wall of the fault 10.

[0046] As the tunnel face 7 moves towards the unexcavated rock mass 6 in front of the TBM3, the distance between the microseismic sensor 9 and the tunnel face 7 increases. When the distance between the microseismic sensor 9 and the tunnel face 7 reaches the limit monitoring distance of the microseismic sensor 9, the microseismic sensor 9 is moved into the borehole 8 close to the tunnel face 7, and this step is continuously repeated until the tunnel face 7 approaches the intersection position of the fault 10 and the tunnel.

[0047] Based on the judgment of the tunneling direction of the tunnel face 7;

[0048] When the tunneling direction of the tunnel face 7 is from the hanging wall of the fault 10 to the footwall of the fault 10, the microseismic sensor 9 is arranged at the hanging wall of the fault 10. After the tunnel face 7 passes the intersection position of the fault 10 and the tunnel, the rear microseismic sensor 9 is arranged at the footwall of the fault 10 again; or

[0049] When the tunneling direction of the tunnel face 7 is from the footwall of the fault 10 to the hanging wall of the fault 10, the microseismic sensor 9 is arranged at the footwall of the fault 10. After the tunnel face 7 passes the intersection position of the fault 10 and the tunnel, the rear microseismic sensor 9 is arranged at the hanging wall of the fault 10 again.

[0050] The monitoring data communicates through the local area network and the data storage 12, and finally completes the microseismic monitoring layout for the fault type rockburst.

[0051] Embodiment 1:

[0052] A certain deep-buried long-distance TBM3 water diversion tunnel is excavated by TBM3. The maximum buried depth of the tunnel is 720m, the length is 20.3km, the lithology is mainly biotite granite, the maximum horizontal principal stress is about 36MPa, and there are multiple faults distributed along the tunnel, with a relatively high risk of fault type rockburst.

[0053] Based on the information of the previous geological survey results, identify the potential area of Fault 10. Select the area of surrounding rock 14 with relatively intact rock mass 5m - 10m behind the tunnel face 7. Drill holes 8 at the positions where the microseismic sensors 9 are arranged. The depth of the drill hole 8 at the left arch shoulder of the tunnel is 3.5m. It is found by borehole camera that the depth of the excavation disturbed area 15 is about 1.5m. The length of the microseismic sensor 9 is 0.1m. To ensure the ability of the microseismic sensor 9 to receive microseismic signals, install the microseismic sensor at the position of 2.5m - 3m. Secondly, the depth of the excavation disturbed area 15 at the right arch shoulder of the tunnel is about 1.6m. According to the requirements of the microseismic sensor installation array, try to increase the coverage range of the microseismic sensor 9 and install the microseismic sensor 9 at the bottom of the drill hole 8. Install 2 microseismic sensors 9 on each of the left and right sides of the tunnel 1. As the tunnel face 7 advances forward about 15m - 20m, install 2 microseismic sensors 9 on each of the left and right sides of the surrounding rock 14 within the range of 5m - 10m behind the tunnel face 7. When the tunnel face 7 continues to advance 15m - 20m, recover the microseismic sensors 9 installed for the first time and install them within the range of 5m - 10m behind the tunnel face. And repeat the above steps following the tunneling of the TBM 3.

[0054] The in - tunnel microseismic system 4 and the out - of - tunnel monitoring and control center 11 are connected to the data storage 12 through the local area network 13, and send the system - collected data to the data storage 13. At the same time, the out - of - tunnel monitoring center 11 synchronously downloads the monitoring data. The microseismic monitoring data 16 shows a significant characteristic of distribution along Fault 10 in space. Therefore, according to the spatial distribution position of the microseismic monitoring data 16, it is obtained that Fault 10 intersects the tunnel 1 in the unexcavated rock mass 6 7m in front of the tunnel face, and it is identified that the tunnel face 7 advances from the footwall to the hanging wall of Fault 10. As the tunnel face 7 gradually approaches the fault, arrange the microseismic sensors 9 on the footwall of Fault 10 and as close to Fault 10 as possible. As the tunnel face 7 excavates beyond Fault 10, arrange the microseismic sensors 10 on the hanging wall of Fault 10 again to realize the monitoring of the potential area of fault - type rockburst.

[0055] Finally, upload the continuously collected microseismic monitoring data 16 to the data storage 12 through the local area network 13 to realize the communication between the monitoring center 11 and the in - tunnel microseismic monitoring system 4, and further ensure the continuity of the monitoring data for the potential fault - type rockburst area.

[0056] In the above technical solution, a microseismic monitoring method for fault - type rockburst in deep - buried long - distance TBM tunnels provided by the present invention has the following beneficial effects:

[0057] The microseismic monitoring method of the present invention transmits the data collected in the tunnel to the outside of the tunnel in a timely manner based on a local area network and a data storage device 12, ensuring the timeliness of data processing and analysis by the monitoring center outside the tunnel, solving the problem that it is difficult to obtain the rock burst monitoring data of deep-buried long-distance TBM tunnels in a timely manner, and storing the original monitoring data in the data storage device to avoid problems such as data damage and loss caused by power outages, thus ensuring the continuity of microseismic monitoring of rock bursts.

[0058] The microseismic monitoring method of the present invention obtains the spatial position relationship between the fractures and the tunnel in the unexcavated area in front of the tunnel face 7 and the fracture 10 occurrence information through the spatial distribution characteristics of microseismic monitoring data, solving the problem that it is difficult to accurately obtain the spatial occurrence position and occurrence information of fractures, and ensuring the reliability of fracture-type rock burst monitoring.

[0059] The microseismic monitoring method of the present invention arranges microseismic sensors 9 on the hanging wall and the footwall of the fracture 10 respectively, which can accurately, timely and effectively capture the fracture slip signal, solving the problem that it is difficult to accurately capture the microseismic events generated by the slip of the fracture 10, and further ensuring the accuracy of fracture-type rock burst monitoring.

[0060] Only some exemplary embodiments of the present invention have been described by way of illustration. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A microseismic monitoring method for fracture-type rockburst in deep-buried long-distance TBM tunnels, characterized in that, The microseismic monitoring method is based on a microseismic system (4) and multiple microseismic sensors (9); The microseismic system (4) is installed on the TBM (3); The data storage (12) and the monitoring control center (11) located outside the tunnel are communicatively connected to the microseismic system (4) through a local area network in the tunnel; The microseismic monitoring method uploads the collected microseismic data to the data storage (12) outside the tunnel through the local area network by the microseismic system (4), and the monitoring control center (11) synchronously downloads the data in the data storage (12), so as to obtain the specific intersection position of the fracture and the unexcavated rock mass by analyzing the spatial distribution characteristics of the microseismic data.

2. The microseismic monitoring method for fracture type rockburst in deep buried long distance TBM tunnel according to claim 1, characterized in that, The microseismic sensors (9) are arranged behind the excavation of the TBM (3) and in the intact rock mass close to the excavation face of the TBM (3).

3. A microseismic monitoring method for fracture-type rock bursts in deep-buried long-distance TBM tunnels according to claim 2, characterized in that, When arranging the microseismic sensors (9), drill holes (8) in the surrounding rock (14) of the tunnel excavated by the TBM (3) and take pictures to identify the excavation disturbance area (15); The depth of the drill hole (8) exceeds the depth of the excavation disturbance area (14), and the microseismic sensor (9) is arranged in the drill hole (8); The microseismic system (4) moves along with the TBM (3).

4. A microseismic monitoring method for fracture type rockburst in deep-buried long-distance TBM tunnels according to claim 3, characterized in that, Obtain the specific intersection position of the fracture (10) and the unexcavated rock mass, as well as the occurrence information of the fracture (10) by analyzing the spatial distribution characteristics of the microseismic data; Judge the driving direction (2) of the tunnel face (7) according to the analysis result.

5. A microseismic monitoring method for fractured rock bursts in deep-buried long-distance TBM tunnels according to claim 4, characterized in that, The driving direction (2) of the tunnel face (7) is to drive from the hanging wall of the fracture (10) to the footwall of the fracture (10), or to drive from the footwall of the fracture (10) to the hanging wall of the fracture (10).

6. A microseismic monitoring method for fracture-type rockburst in deep-buried long-distance TBM tunnels according to claim 5, characterized in that, As the tunnel face (7) moves forward to the unexcavated rock mass (6) in front of the TBM (3), the distance between the microseismic sensor (9) and the tunnel face (7) increases. When the distance between the microseismic sensor (9) and the tunnel face (7) reaches the limit monitoring distance of the microseismic sensor (9), move the microseismic sensor (9) into the drill hole (8) close to the tunnel face (7), and continuously repeat this step until the tunnel face (7) approaches the intersection position of the fracture (10) and the tunnel.

7. A microseismic monitoring method for fracture-type rockburst in deep-buried long-distance TBM tunnels according to claim 5 or 6, characterized in that, Based on the judgment of the driving direction (2) of the tunnel face (7); When the driving direction (2) of the tunnel face (7) is to drive from the hanging wall of the fracture (10) to the footwall of the fracture (10), the microseismic sensor (9) is arranged at the hanging wall of the fracture (10). After the tunnel face (7) passes the intersection position of the fracture (10) and the tunnel, arrange the rear microseismic sensor (9) at the footwall of the fracture (10) again; or When the driving direction of the tunnel face (7) is to drive from the footwall of the fracture (10) to the hanging wall of the fracture (10), the microseismic sensor (9) is arranged at the footwall of the fracture (10). After the tunnel face (7) passes the intersection position of the fracture (10) and the tunnel, arrange the rear microseismic sensor (9) at the hanging wall of the fracture (10) again.

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