Distributed optical fiber monitoring system for rock mass change state monitoring

Abstract

The invention discloses a distributed optical fiber monitoring system for monitoring a rock mass change state, relates to the field of monitoring equipment, is applied to an underground cavity and can monitor axial and radial fracture signals of the underground cavity at the same time so as to facilitate three-dimensional positioning of a seismic source at a fracture occurrence position. The distributed optical fiber monitoring system comprises a first optical fiber and a second optical fiber. The first optical fibers are arranged on the cavern wall in the axial direction of the underground cavern and can monitor fracture signals distributed in the axial direction of the underground cavern; the second optical fiber is mainly composed of a peripheral side optical fiber section and a reversing transition section, and the peripheral side optical fiber section is used for being arranged on the cavern wall along the cross section contour of the cavern wall and can monitor fracture signals distributed in the radial direction of the underground cavern. Therefore, the distributed optical fiber monitoring system can simultaneously monitor the axial and radial fracture signals of the underground cavern, realizes the space monitoring of the underground cavern, and facilitates the more accurate three-dimensional positioning of a seismic source at the fracture occurrence position.

Description

Technical Field

[0001] The invention belongs to the field of monitoring equipment, and in particular relates to a distributed optical fiber monitoring system for monitoring rock mass change status. Background Art

[0002] Affected by the disturbance of engineering excavation, the original state of the rock mass is changed, and its changed state includes but is not limited to temperature, strain and rock fracture; the changed state of the rock mass will directly affect the safety of engineering construction and long-term operation. Effective monitoring and prediction of its changed state is an important measure to ensure engineering safety. The changed state of the rock mass not only involves the change of deformation state and rock mass fracture caused by the adjustment of the stress field, such as surrounding rock collapse and rock burst, but may also involve changes in the temperature field, such as water inrush and geological disposal of high-level radioactive waste. As one of the typical representatives of rock mass fracture disasters, rock burst is not only an extremely dangerous dynamic disaster, but also still lacks equipment and analysis technology that can be effectively monitored and predicted.

[0003] Rockburst is caused by the sudden and violent release of elastic deformation potential accumulated in the rock mass due to external disturbance. Before the rock breaks, only the internal deterioration of the rock mass occurs, there will be slight vibrations, and sounds that cannot be distinguished by human ears. Rock breakage usually occurs within 24 hours after the rock mass is excavated, and the duration is generally 1 to 2 months, and some extend for more than 1 year. In severe cases, earthquakes of magnitude 4 to 6 can be detected, with an intensity of 7 to 8 degrees. Therefore, how to monitor and predict rock breakage based on the characteristics of vibration and sound generated before and during rock breakage, determine the location, magnitude, and possible duration of rock breakage, and take corresponding preventive measures, can greatly reduce or eliminate the casualties and property losses of construction personnel caused by rock breakage.

[0004] At present, the on-site measurement and prediction of rock burst mainly involves predicting the location and possibility of rock burst through on-site monitoring methods during construction, such as microseismic (MS) method, acoustic emission (AE) method, drilling cuttings method, electromagnetic radiation (EMR) method, distributed optical fiber monitoring method, etc. Among them, the distributed optical fiber monitoring method uses optical fiber strips to monitor the vibration and sound and other rupture signals generated before and during the rock rupture at the monitoring point. There are problems such as relatively scattered monitoring signals, difficult deployment, and low survival rate in complex geological environments.

[0005] For example: The Chinese utility model patent with the authorization announcement number CN212003266U discloses a rockburst monitoring system based on distributed optical fiber sensing, which uses multiple monitoring armored optical cables to be installed and fixed along the top and supporting rock or supporting walls on both sides of the tunnel being excavated or completed, or on the working surface being excavated along the mountain or ore body; one end of the multiple 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. Since the tunnel chambers buried deep underground are generally excavated by blasting, the surrounding rock of the cave wall has large fluctuations. Using optical fiber strips for rockburst monitoring will result in poor coupling between the optical fiber and the surrounding rock. Moreover, in order to couple the optical fiber with the surrounding rock, it is often necessary to bend the optical fiber to a large extent at the monitoring point, thereby greatly reducing the survival rate of the optical fiber. In addition, the above patent adopts a linear layout along the tunnel axis and is not suitable for facilities with multiple staggered caverns, such as deep underground laboratories, underground factories and other projects; this is because the optical fiber is more sensitive to deformation along its axis. This linear layout method can often only monitor the rupture signals distributed along the tunnel axis, and cannot monitor the rupture signals in directions other than the tunnel axis, making it difficult to achieve three-dimensional positioning of the earthquake source where the rupture occurs.

[0006] Therefore, there is an urgent need in the art for a distributed optical fiber monitoring system for monitoring rock mass change status to solve the above technical problems. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a distributed optical fiber monitoring system for monitoring rock mass change state, which can be applied to underground caverns to simultaneously monitor axial and radial fracture signals of the underground caverns, so as to facilitate three-dimensional positioning of the earthquake source at the fracture occurrence location.

[0008] The technical solution adopted by the present invention to solve the technical problem is: a distributed optical fiber monitoring system for monitoring rock mass change state, comprising a first optical fiber, which is arranged on the wall of an underground cave along the axial direction of the cave;

[0009] Also includes a second optical fiber, the second optical fiber includes a peripheral optical fiber segment and a switching transition segment;

[0010] The peripheral optical fiber segment is used to be arranged on the cave wall along the cross-sectional profile thereof;

[0011] There are at least two peripheral optical fiber segments which can be arranged at intervals along the axial direction of the underground cavern. The peripheral optical fiber segments are sequentially connected end to end through the switching transition segment to make the optical path of the second optical fiber continuous.

[0012] Furthermore, the cavern wall includes a left cavern wall, a top cavern wall and a right cavern wall;

[0013] There are three or more first optical fibers, at least one of which is arranged on the left wall of the cave, at least one of which is arranged on the top wall of the cave, and at least one of which is arranged on the right wall of the cave.

[0014] Further, the number of the first optical fibers is six;

[0015] One of them is used to be laid on the left wall of the cavern and is located at 1 / 3 of the height of the left wall of the cavern;

[0016] One of them is used to be laid on the left wall of the cavern and is located at 2 / 3 of the height of the left wall of the cavern;

[0017] One of them is used to be laid on the top wall of the cavern and is located at a position of 1 / 3 of the arc length of the top wall of the cavern;

[0018] One of them is used to be laid on the top wall of the cavern and is located at a position of 2 / 3 of the arc length of the top wall of the cavern;

[0019] One of them is used to be laid on the right wall of the cavern and is located at 1 / 3 of the height of the right wall of the cavern;

[0020] One of them is used to be laid on the right wall of the cavern and is located at 2 / 3 of the height of the right wall of the cavern.

[0021] Furthermore, the distributed optical fiber monitoring system also includes a multi-channel optical fiber sensor regulator and a data processing terminal;

[0022] One end of the first optical fiber and the second optical fiber are both used to extend to the excavation surface of the underground cavern, and both are provided with a light extinction device;

[0023] The other ends of the first optical fiber and the second optical fiber are optically connected to a multi-channel optical fiber sensor regulator through an outgoing optical fiber that can be arranged along the wall of the shaft;

[0024] The multi-channel optical fiber sensing regulator is communicatively connected with the data processing terminal.

[0025] Furthermore, the first optical fiber and / or the second optical fiber is optically connected to an integrated optical fiber sensor for collecting rupture signals in a key monitoring area;

[0026] The integrated optical fiber sensor comprises a deformable body and a third optical fiber, wherein the third optical fiber comprises a first optical fiber segment and a second optical fiber segment connected to each other;

[0027] The first optical fiber segment is arranged on the peripheral wall of the deformation body and is spirally wound around the axial direction of the deformation body for at least one circle to form a first optical fiber coil;

[0028] The second optical fiber segment includes a straight line segment arranged on the peripheral wall of the deformation body along the axial direction. The straight line segments are at least two and are evenly distributed around the circumference of the deformation body. The straight line segments are connected end to end in sequence through an arc-shaped reversing segment to form a second optical fiber coil with a continuous optical path.

[0029] Furthermore, the integrated optical fiber sensor also includes a vibration conduction component;

[0030] The vibration transmission component is arranged at the bottom of the deformation body, and is used for transmitting the vibration generated by the rock mass fracture to the deformation body.

[0031] Further, the vibration conduction component includes a rigid conduction sheet and a rigid vibration ball;

[0032] One side surface of the rigid conductive sheet is attached to the bottom surface of the deformable body;

[0033] The rigid vibration balls are arranged on the other side surface of the rigid conductive sheet. There are at least three rigid vibration balls and they are distributed in a circular array with the extension line of the axis of the deformable body as the array center line.

[0034] Furthermore, the integrated optical fiber sensor also includes a protective housing, an optical fiber guide tube and a rock coupling component;

[0035] The deformed body is cylindrical;

[0036] The protective shell cover is arranged outside the deformable body, and the bottom of the vibration conducting component is at least partially exposed outside the protective shell;

[0037] The optical fiber guide tube comprises an inner guide tube and an outer guide tube; the inner guide tube is inserted into the protective shell along the axial direction of the deformable body; the outer guide tube is arranged outside the protective shell, and a partial tube section thereof is opened and connected to a tube opening at one end of the inner guide tube;

[0038] The third optical fiber also includes an entry optical fiber segment and an exit optical fiber segment; the tail end of the entry optical fiber segment passes through the optical fiber guide tube from one end of the outer guide tube, passes through the side of the inner guide tube, and is connected to the head end of the first optical fiber segment; the head end of the exit optical fiber segment is connected to the tail end of the second optical fiber segment, and the tail end thereof passes through the optical fiber guide tube from the side of the inner guide tube, and passes through the other end of the outer guide tube.

[0039] The rock mass coupling component is arranged at the bottom of the vibration conduction component and is used for coupling connection with the rock mass.

[0040] Furthermore, the rock mass coupling component is a coupling cone head, and the coupling cone head is connected to the bottom of the vibration conduction component through its bottom surface.

[0041] Furthermore, the rock mass coupling component includes a coupling base and a coupling connector;

[0042] One side surface of the coupling base is attached to the bottom of the vibration conducting component;

[0043] The coupling connector is arranged on the coupling base, and at least part of its connecting portion passes through the other side surface of the coupling base;

[0044] The number of the coupling connectors is at least three, and they are distributed in a ring array with the extension line of the axis of the deformation body as the array center line.

[0045] The beneficial effects of the present invention are as follows:

[0046] (1) The distributed optical fiber monitoring system for monitoring the state of rock mass changes provided by the present invention is arranged in an underground cavern to monitor the fracture signals such as vibration and sound generated before and during the fracture of the rock mass. The first optical fiber is arranged on the cavern wall along the axial direction of the underground cavern, and can monitor the fracture signals distributed along the axial direction of the underground cavern; the second optical fiber is mainly composed of a circumferential optical fiber segment and a reversing transition segment. The circumferential optical fiber segment is arranged on the cavern wall along the cross-sectional profile of the cavern wall, and can monitor the fracture signals distributed along the radial direction of the underground cavern. It can be seen that the distributed optical fiber monitoring system can simultaneously monitor the axial and radial fracture signals of the underground cavern, realize the spatial monitoring of the underground cavern, and facilitate more accurate three-dimensional positioning of the earthquake source at the fracture location.

[0047] (2) The distributed optical fiber monitoring system also includes a multi-channel optical fiber sensor regulator and a data processing terminal; the multi-channel optical fiber sensor regulator can simultaneously obtain the strain signals measured by the first optical fiber and the second optical fiber and send them to the data processing terminal; the data processing terminal can analyze and process the strain signals, which is conducive to real-time feedback of the energy size and location distribution of the rupture event of the underground cavern during the excavation process, so as to predict in advance the area where disaster events such as rock burst or collapse may occur based on the location information and energy information, thereby guiding the staff to take preventive and disposal measures in advance, and minimize the casualties and property losses caused by the disaster events.

[0048] (3) By connecting an integrated optical fiber sensor to the first optical fiber and / or the second optical fiber, the integrated optical fiber sensor can be used to monitor the key monitoring area in the underground cavern, thereby improving the monitoring effect of the distributed optical fiber monitoring system. When the deformable body of the integrated optical fiber sensor senses a rupture signal, the first optical fiber coil and the second optical fiber coil on the peripheral wall of the deformable body will deform, thereby realizing the monitoring of the rupture signal; since the optical fiber can monitor the rupture signal along its axial direction, the first optical fiber coil that is spirally wound around the axial direction of the deformable body for at least one circle can effectively monitor the longitudinal and transverse strains perpendicular to the axial direction of the deformable body caused by vibration, and the second optical fiber coil that has two or more straight segments uniformly distributed around the circumference of the deformable body and arranged along the axial direction of the deformable body can effectively monitor the strain along the axial direction of the deformable body caused by vibration. It can be seen that the integrated optical fiber sensor can simultaneously obtain the components of the X, Y, and Z directions corresponding to the rupture signal, and has a good monitoring effect on the rupture signals such as vibration and sound generated before and during the rupture.

[0049] (4) Based on the monitoring method implemented by the distributed optical fiber monitoring system, the deformation field and temperature field of the monitored cavern rock mass obtained synchronously are three-dimensional distributions, which can more truly reflect the deformation field state and temperature field differences in different parts of the cavern space morphology.

[0050] The technical effects brought about or directly produced by other technical features of the present invention will be described in detail in the subsequent specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the implementation structure of the present invention;

[0052] Figure 2 It is a schematic diagram of the implementation structure of an implementation mode of the integrated optical fiber sensor in the present invention;

[0053] Figure 3 It is an analysis diagram of the monitoring rupture signal when the optical fiber is wound;

[0054] Figure 4 yes Figure 3 A schematic diagram of an unfolded state of an optical fiber in a winding arrangement;

[0055] Figure 5 is based on Figure 3 The relationship diagram between the local coordinate system n-axis and the global coordinate system;

[0056] Figure 6 It is a schematic diagram of the implementation structure of another embodiment of the integrated optical fiber sensor in the present invention;

[0057] Figure 7It is a schematic diagram of the implementation structure of another embodiment of the integrated optical fiber sensor in the present invention;

[0058] Marked in the figure are: underground cavern 1, cavern wall 11, first optical fiber 2, second optical fiber 3, peripheral optical fiber segment 31, reversing transition segment 32, multi-channel optical fiber sensor regulator 4, data processing terminal 5, deformable body 100, entering optical fiber segment 210, first optical fiber coil 220, second optical fiber coil 230, straight segment 231, arc-shaped reversing segment 232, lead-out optical fiber segment 240, vibration conduction component 300, rigid conduction sheet 310, rigid vibration ball 320, protective shell 400, optical fiber guide tube 500, inner guide tube 510, outer guide tube 520, coupling cone head 600, coupling base 710, coupling connector 720. DETAILED DESCRIPTION

[0059] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. The same reference numerals in the accompanying drawings represent components with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0060] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate directions or positions, and dimensional relationships based on the directions or position relationships shown in the accompanying drawings, and are only for the convenience of description, and do not indicate or imply that the referred device or component must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0061] When the terms "about", "around", etc. are used to describe a numerical range, they usually refer to an error within ±10%, for example: about 100mm, usually refers to 90-110mm. When the term "more" refers to a quantity, it usually refers to a quantity of three or more, for example: "a plurality" usually refers to three or more. The expression "mainly composed of..." is interpreted as also containing structural components not mentioned in the sentence. The term "and / or" is only a description of the association relationship of the associated objects, indicating that there can be three relationships, for example: A and / or B, which can mean: A exists alone, A and B exist at the same time, and B exists alone. The term "communication connection" refers to the communication between connected devices through the transmission interaction of signals, which can be divided into wired connection and wireless connection; wired connection is usually a cable, optical fiber and other connection; wireless connection is usually a radio communication, Bluetooth, infrared, NFC and other connections. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0062] like Figure 1 As shown, a distributed optical fiber monitoring system for monitoring rock mass change status includes a first optical fiber 2 and a second optical fiber 3;

[0063] The first optical fiber 2 is used to be arranged on the cavern wall 11 along the axial direction of the underground cavern 1 to monitor the rupture signal distributed along the axial direction of the underground cavern 1; the first optical fiber 2 is generally fixed to the cavern wall 11 by an adhesive such as cement, or fixed to the cavern wall 11 by a fixing member such as a line clip; the number of the first optical fibers 2 arranged is generally selected according to the monitoring needs, and usually a plurality of first optical fibers 2 are arranged according to the optical fiber resolution requirements;

[0064] The second optical fiber 3 is fixed on the chamber wall 11 in the same manner as the first optical fiber 2; the second optical fiber 3 includes a peripheral optical fiber segment 31 and a reversing transition segment 32;

[0065] The peripheral optical fiber segment 31 is used to be laid on the cavern wall 11 along the cross-sectional profile thereof, so as to monitor the fracture signals distributed radially along the underground cavern 1; when laying out the peripheral optical fiber segment 31, it is generally perpendicular to the axial direction of the underground cavern 1, and is wired in the height direction of the left wall of the cavern, the arc length direction of the cavern top wall, and the height direction of the right wall of the cavern in sequence; since the cavern top wall is an arc, the radius of the curved arc of the peripheral optical fiber segment 31 during the transition from the left wall of the cavern to the cavern top wall and from the cavern top wall to the right wall of the cavern needs to be greater than 20 times the diameter of the bare optical fiber;

[0066] There are at least two circumferential optical fiber segments 31, which can be arranged at intervals along the axial direction of the underground cavern 1. The circumferential optical fiber segments 31 are connected end to end in sequence through the reversing transition segment 32 to make the optical path of the second optical fiber 3 continuous. The more circumferential optical fiber segments 31 there are, the higher the monitoring accuracy will be, but it will lead to signal acquisition redundancy. Therefore, the specific number of circumferential optical fiber segments 31 can usually be determined based on comprehensive consideration of factors such as monitoring effect requirements, the minimum curvature of the reversing transition segment 32, production cost, and production difficulty. The reversing transition segment 32 is usually smoothly connected to the circumferential optical fiber segment 31, and the curvature of the reversing transition segment 32 must be sufficient to basically not affect the signal transmission of the optical fiber. It is usually required that the arc radius of the reversing transition segment 32 is greater than 20 times the diameter of the bare optical fiber.

[0067] The distributed optical fiber monitoring system is mainly used to be deployed in the underground cavern 1 to monitor the fracture signals such as vibration and sound generated before and during the rock fracture. It can simultaneously monitor the axial and radial fracture signals of the underground cavern 1, realize the spatial monitoring of the underground cavern, and facilitate more accurate three-dimensional positioning of the fracture location.

[0068] Usually, if you want to monitor the rupture signal with high precision, the spacing between the optical fibers should be equal to or close to the resolution of the optical fibers, and the resolution is preset according to the monitoring effect requirements; the spacing between the optical fibers refers to: the spacing between two adjacent first optical fibers 2, and / or the spacing between two adjacent peripheral optical fiber segments 31. If the spacing between the optical fibers is too large, there will be the following deficiencies: incomplete acquisition of signals, low monitoring accuracy, and increased data sparsity; if the spacing between the optical fibers is too small, there will be the following deficiencies: redundant signal acquisition, waste of resources, and more computing and storage resources are required to process and store these redundant information; therefore, the spacing between the optical fibers is usually limited to 1 to 5 meters.

[0069] Specifically, the second optical fiber 3 is laid out on the cavern wall 11 as follows: cement or a wire clip is used to vertically lay the second optical fiber 3 close to the wall surface of the left side wall of the cavern, and it is laid all the way to the top of the left side wall of the cavern, and then it is bent upward in an arc shape with a radius greater than 20 times the diameter of the bare optical fiber, and continues to extend upward along the top of the left side wall of the cavern, close to the wall surface, and transitions to the cavern top wall, and then it is bent and laid perpendicularly to the axial direction of the underground cavern 1 along the cavern top wall until it extends to the top of the right side wall of the cavern, and then it is laid downward along the wall surface of the right side wall of the cavern, and extends It extends to the bottom of the right side wall of the cavern to form a circumferential optical fiber segment 31; then, it is bent to form a switching transition segment 32 that changes the direction of the second optical fiber 3, and then a circumferential optical fiber segment 31 is laid out with the bottom of the right side wall of the cavern as the starting point and the bottom of the left side wall of the cavern as the end point. The second optical fiber 3 is bent in a cycle until it is laid to the excavation surface. The spacing between any two adjacent circumferential optical fiber segments 31 should be less than or equal to the resolution of the optical fiber; taking the resolution set to 2m as an example, the spacing between two adjacent circumferential optical fiber segments 31 should be 2m.

[0070] The first optical fiber 2 and the second optical fiber 3 of the distributed optical fiber monitoring system are generally not arranged on the bottom surface of the underground cavern 1 in order to prevent construction disturbance from reducing the survival rate of the optical fiber and to prevent too many construction noise signals from being monitored.

[0071] In order to improve the monitoring effect, Figure 1 As shown, in some embodiments of the present invention, the cavern wall 11 includes a left side wall of the cavern, a top wall of the cavern and a right side wall of the cavern; there are three or more first optical fibers 2, at least one of which is used to be arranged on the left side wall of the cavern, at least one of which is used to be arranged on the top wall of the cavern, and at least one of which is used to be arranged on the right side wall of the cavern.

[0072] In some embodiments of the present invention, both the first optical fiber 2 and the second optical fiber 3 are armored optical fibers. Armored optical fibers can enhance the survival rate of optical fibers in complex geological environments, and their armor shells are usually made of corrosion-resistant and anti-aging materials, preferably made of rubber.

[0073] For example Figure 1 As shown, in some embodiments of the present invention, there are six first optical fibers 2; one of which is used to be arranged on the left wall of the cavern and is located at 1 / 3 of the height of the left wall of the cavern; one of which is used to be arranged on the left wall of the cavern and is located at 2 / 3 of the height of the left wall of the cavern; one of which is used to be arranged on the top wall of the cavern and is located at 1 / 3 of the arc length of the top wall of the cavern; one of which is used to be arranged on the top wall of the cavern and is located at 2 / 3 of the arc length of the top wall of the cavern; one of which is used to be arranged on the right wall of the cavern and is located at 1 / 3 of the height of the right wall of the cavern; one of which is used to be arranged on the right wall of the cavern and is located at 2 / 3 of the height of the right wall of the cavern. Such uniform arrangement of the first optical fibers 2 can improve the accuracy of the optical fiber monitoring signal; two first optical fibers 2 are arranged on the same cavern wall, and the signal data monitored by the two first optical fibers 2 can complement and verify each other. Taking a 6m high underground cavern 1 as an example, in order to monitor the rupture signal with high precision, the first optical fiber 2 is arranged in the above manner, and the resolution of the optical fiber is set to be about 2m.

[0074] For example Figure 1 As shown, in some embodiments of the present invention, the distributed optical fiber monitoring system further includes a multi-channel optical fiber sensor regulator 4 and a data processing terminal 5;

[0075] One end of the first optical fiber 2 and the second optical fiber 3 are both used to extend to the excavation surface of the underground cavern 1, and both are provided with a light extinction device; the light extinction device is used to eliminate the reflected signal of the first optical fiber 2 and the second optical fiber 3 close to the excavation surface end;

[0076] The other ends of the first optical fiber 2 and the second optical fiber 3 are optically connected to the multi-channel optical fiber sensor regulator 4 through the lead-out optical fiber that can be arranged along the wall of the shaft;

[0077] The multi-channel optical fiber sensor regulator 4 is used to simultaneously obtain the strain signals measured by the first optical fiber 2 and the second optical fiber 3. The multi-channel optical fiber sensor regulator 4 can be of various types, preferably a quantitative acoustic data acquisition system based on optical phase and amplitude demodulation developed by FEBUS Optics of France, model: TV155; the multi-channel optical fiber sensor regulator 4 is communicatively connected to the data processing terminal 5;

[0078] The data processing terminal 5 is used to analyze and process the strain signal, which is conducive to real-time feedback of the energy size and position distribution of the rupture event of the underground cavern 1 during the excavation process, so that according to the position information and energy information, the area where the rock burst event may occur can be predicted in advance, thereby guiding the staff to carry out reinforcement treatment in advance, and minimizing the casualties and property losses of construction personnel caused by the rock burst; the data processing terminal 5 can be a smart phone, a tablet computer, a computer or a server; the data processing terminal 5 can analyze and process the strain signal in a variety of ways, such as: Reference 1 (Song Guangdong. Research on microseismic signal acquisition and identification and source location based on optical fiber sensing [D]. China University of Mining and Technology (Beijing), 2019.) and Reference 2 (Luo B, Trainor-Guitton W, The method described in E, et al. Horizontally orthogonal distributed acoustic sensing array for earthquake-and ambient-noise-based multichannel analysis of surface waves [J]. Geophysical Journal International, 2020, 222(3): 2147-2161.).

[0079] Based on the above-mentioned distributed optical fiber monitoring system, before the rock mass in the monitored area breaks, local stress concentration occurs in the rock mass, thereby inducing the occurrence of microseismic events. The optical fiber arranged on the cave wall 11 monitors the seismic waves of these microseismic signals and transmits them to the multi-channel optical fiber sensor regulator 4, and at the same time transmits them to the data processing terminal 5 in real time. The data processing terminal 5 can calculate the spatial coordinate position and the time of occurrence of the rupture event based on the difference in the initial arrival of the longitudinal wave and the transverse wave of the same microseismic signal arriving at different monitoring points of the optical fiber. At the same time, according to the amplitude of the monitored rupture signal, the energy of the microseismic event can also be determined. Subsequently, the data processing terminal 5 can present information such as the rupture position and energy in real time, so as to determine the area where rock burst may occur, and make a timely warning so that the staff can reinforce the area where rock burst may occur.

[0080] like Figure 2 , Figure 6 or Figure 7 As shown, in some embodiments of the present invention, the first optical fiber 2 and / or the second optical fiber 3 are optically connected with an integrated optical fiber sensor for collecting rupture signals in the key monitoring area; the integrated optical fiber sensor can be set as needed One, two or more, when more than two integrated optical fiber sensors are arranged, because the integrated optical fiber sensor is connected to the first optical fiber 2 and / or the second optical fiber 3, the specific connection section position of the optical fiber will be determined in advance according to actual needs, and the collected signal on each section of the first optical fiber 2 and / or the second optical fiber 3 can be displayed and obtained from the data processing terminal 5 in real time, so the signal monitored by the integrated optical fiber sensor at which position can be determined according to the layout position of the integrated optical fiber sensor on the optical fiber. Therefore, the position of the optical fiber will be accurately calibrated before formal monitoring. The specific method is: first, the optical fiber is connected to the multi-channel optical fiber sensor regulator 4, and the length of a certain position of the optical fiber is measured, and the position is knocked. After the vibration generated by the knocking is processed by the multi-channel optical fiber sensor regulator 4, the amplitude of the knocking position and other information will be highlighted on the data processing terminal 5, and the position can be calibrated as the measured length on the data processing terminal 5.

[0081] The areas that need to be monitored in the underground cavern 1 are usually determined according to the construction requirements, and generally include the rock mass near the entrance and exit of the underground cavern 1, the area with structural deformation in the underground cavern 1, the thinner rock layer in the underground cavern 1, the area with more cracks in the underground cavern 1, etc.;

[0082] The integrated optical fiber sensor includes a deformable body 100 and a third optical fiber, wherein the third optical fiber includes a first optical fiber segment and a second optical fiber segment connected to each other;

[0083] The deformable body 100 is a component that will produce elastic deformation under the action of load (such as vibration); the deformable body 100 is usually made of elastic material, preferably made of rubber; the deformable body 100 is usually a regular columnar structure, preferably a cylindrical structure, so as to ensure that it can produce deformation adapted to the vibration size, vibration frequency and vibration direction under the action of vibration, so as to ensure the monitoring effect;

[0084] The first optical fiber segment is arranged on the peripheral wall of the deformable body 100, and is spirally wound around the axial direction of the deformable body 100 for at least one circle to form a first optical fiber coil 220; because the optical fiber can monitor the rupture signal along its axial direction, and each circle of the first optical fiber coil 220 is nearly perpendicular to the axial direction of the deformable body 100, the first optical fiber coil 220 can effectively monitor the longitudinal and transverse strains perpendicular to the axial direction of the deformable body 100 caused by vibration; the more circles of the first optical fiber coil 220 and the smaller the distance between two adjacent circles, the better the monitoring effect; the specific number of circles of the first optical fiber coil 220 and the distance between two adjacent circles can usually be determined based on comprehensive consideration of factors such as actual monitoring effect requirements, production cost, production difficulty, and signal collection amount;

[0085] The second optical fiber segment includes a straight segment 231 arranged on the peripheral wall of the deformable body 100 along the axial direction thereof, and there are at least two straight segments 231 that are evenly distributed around the circumference of the deformable body 100. The straight segments 231 are connected end to end in sequence through the arc-shaped reversing segment 232 to form a second optical fiber coil 230 with a continuous optical path; the arc-shaped reversing segment 232 is usually smoothly connected with the straight segment 231, and the curvature of the arc-shaped reversing segment 232 must be sufficient to basically not affect the signal transmission of the optical fiber; the strain along the axial direction of the deformable body 100 caused by vibration can be effectively monitored through the straight segment 231. The more straight segments 231 there are, the higher the monitoring accuracy is, but it will cause signal acquisition redundancy. Therefore, the specific number of straight segments 231 can usually be determined based on comprehensive consideration of factors such as monitoring effect requirements, the minimum curvature of the arc-shaped reversing segment 232, production cost, production difficulty, and signal acquisition amount.

[0086] The above-mentioned integrated optical fiber sensor can simultaneously obtain the components of the fracture signal in the three directions of X, Y, and Z, and has a good monitoring effect on the fracture signals such as vibration and sound generated before and during the rock fracture. The theoretical basis for the simultaneous monitoring of the fracture signal components in three mutually perpendicular directions by optical fiber is as follows:

[0087] Combined with Figure 3 , Figure 4 and Figure 5 Analyze the crack signal components that can be monitored when the optical fiber is wound. Figure 3 Point P is any position on the optical fiber, α is the winding angle, corresponding to Figure 2In the embodiment, the tilt angle of the front view projection of the first optical fiber coil 220 corresponds to Figure 3 The angle between the axial direction of the optical fiber and the tangent line of the deformed body at point A; AA′ is the optical fiber winding section, e x 、e y 、e z are the strains of the X, Y, and Z components caused by vibration at the location of the optical fiber. They are actual quantities and are calculated according to formulas 1 to 5. Because only the axial strain of the optical fiber can be obtained during the monitoring process, e x 、e y 、e z The three component strains can be obtained by calculating the winding angle α and the following other parameters. is the axial strain of the optical fiber at point P, P-lmn is the local coordinate system of point P, n direction is the axial direction of the optical fiber winding section, θ is the rotation angle, θ nx is the angle between the n-axis in the local coordinate system P-lmn coordinate system and the x-axis in the global coordinate system. Similarly: θ ny is the angle between the n-axis in the local coordinate system P-lmn coordinate system and the y-axis in the global coordinate system, θ nz It is the angle between the n-axis in the local coordinate system P-lmn coordinate system and the z-axis in the global coordinate system.

[0088] Depend on Figure 3 , Figure 4 and Figure 5 It can be deduced that the axial strain of the optical fiber at point P is The relationship with the three strain components is:

[0089]

[0090] Three coefficients R that affect the axial strain of optical fiber nx , R ny , R nz They are:

[0091]

[0092] θ nx ,θ ny ,θ nz The relationship with the winding angle α is:

[0093]

[0094] Where: R nx , R ny , R nz They represent the direction cosines between the n-axis and the x-, y-, and z-axes respectively; r is the fiber winding radius. Figure 2 or Figure 6 or Figure 7In the embodiment, r is equal to the radius of the deformable body 100. k is Figure 3 h is the length of the AP segment in the unfolded state of the optical fiber in the winding setting; h is the height of point P in the unfolded state of the optical fiber in the winding setting.

[0095] Formula 2 can be expressed in matrix as:

[0096]

[0097] It can be shortened to:

[0098] E=GE0...(Formula 5);

[0099] Where: E is the axial strain matrix of the fiber in the winding arrangement; G is R nx , R ny , R nz The extended matrix composed of E0 is the actual three-component strain e of the optical fiber in the winding setting. x 、e y 、e z The matrix formed.

[0100] Based on formulas 1 to 5, the strain E0 of the optical fiber monitoring point in three components can be calculated according to the collected optical fiber axial strain E. It can be seen from formulas 1 to 5 that the three strain components generated by the optical fiber receiving the rupture signal are related to the winding angle α. When α increases, e z The weight increases, and e x and e y The component strain decreases, and when α decreases, e z The weight decreases, and e x and e y The component increases. Therefore, in order to be able to monitor the three more obvious strain component signals at the same time. Therefore, the present invention adopts two different winding methods to set the optical fiber segment on the deformable body 100, that is, one is a first optical fiber segment, which is arranged on the peripheral wall of the deformable body 100 and is spirally wound around the axial direction of the deformable body 100 for at least one circle to form a first optical fiber coil 220; the other is a second optical fiber segment, which includes a straight line segment 231 arranged on the peripheral wall of the deformable body 100 along the axial direction, and the straight line segments 231 are at least two and are evenly distributed around the circumference of the deformable body 100. The straight line segments 231 are connected end to end in sequence through the arc-shaped reversing segment 232 to form a second optical fiber coil 230 with a continuous optical path; the winding angle α of the straight line segment 231 is 90°, and the e monitored by it is z When the winding angle α of the first optical fiber coil 220 is close to 0°, the monitored e x and e y The component is close to the maximum value.

[0101] like Figure 2 , Figure 6 or Figure 7 As shown, in some embodiments of the present invention, the first optical fiber coil 220 is located at the lower side of the second optical fiber coil 230, and the first optical fiber coil 220 is wound from bottom to top. Such a configuration is not only compact in structure, but also conducive to ensuring the continuity of the optical path of the third optical fiber, so as to ensure the sensitivity and accuracy of monitoring. The winding angle α of the first optical fiber coil 220 should be as small as possible, and the winding length can be determined according to factors such as actual measurement requirements and the size of the deformable body 100, and is usually wound about 1m.

[0102] In some embodiments of the present invention, an integrated optical fiber sensor vibration transmission component 300 is provided at the bottom of the deformable body 100, and is used to transmit the vibration generated by the rock mass fracture to the deformable body 100, so as to improve the monitoring sensitivity and accuracy. The vibration transmission component 300 can be a variety of components, usually made of rigid materials, preferably made of solid metal.

[0103] For example Figure 2 , Figure 6 or Figure 7 As shown, in some embodiments of the present invention, the vibration conduction component 300 includes a rigid conduction sheet 310 and a rigid vibration ball 320;

[0104] One side surface of the rigid conductive sheet 310 is attached to the bottom surface of the deformable body 100, and is used to uniformly conduct the vibration energy to the deformable body 100; the rigid conductive sheet 310 is usually a sheet-shaped component adapted to the bottom surface of the deformable body 100, and is usually made of a rigid material, preferably a metal material, such as a steel sheet made of steel; the rigid conductive sheet 310 can also prevent the rigid vibration ball 320 from directly contacting the deformable body 100, thereby preventing the vibration energy from being consumed or weakened due to the friction effect;

[0105] The rigid vibration balls 320 are arranged on the other side surface of the rigid conductive sheet 310. There are at least three rigid vibration balls 320 and they are distributed in a circular array with the extension line of the axis of the deformable body 100 as the center line of the array. Since the rigid vibration balls 320 have a regular shape and high dimensional accuracy, they can accurately transmit vibrations. Moreover, the rigid vibration balls 320 have high hardness and rigidity, which can reduce energy loss in the process of transmitting vibrations. In addition, the rigid vibration balls 320 distributed in a plurality of circular arrays can ensure that they can uniformly transmit rupture signals. Therefore, when the rigid vibration balls 320 are subjected to external vibrations, only a small elastic deformation will occur, and they will quickly recover and generate vibration waves, which will propagate along the rigid vibration balls 320, thereby accurately and efficiently transmitting the rupture signals to the rigid conductive sheet 310. The rigid vibration balls 320 are usually made of rigid materials, preferably made of metal materials, such as steel balls made of steel.

[0106] In order to simplify the structure and ensure a good vibration conduction effect, in some embodiments of the present invention, the number of the rigid vibration balls 320 is preferably set to three or four.

[0107] In order to effectively reduce the loss of vibration energy at the connection between the rigid vibration ball 320 and the rigid conductive sheet 310 and improve the connection effect, in some embodiments of the present invention, it is preferred to make the rigid vibration ball 320 and the rigid conductive sheet 310 face-to-face contact, that is, an arc-shaped groove is provided on the other side surface of the rigid conductive sheet 310, so that a part of the rigid vibration ball 320 is embedded in the arc-shaped groove to form an arc-shaped surface-fit connection.

[0108] For example Figure 2 , Figure 6 or Figure 7 As shown, in some embodiments of the present invention, the integrated optical fiber sensor further includes a protective housing 400, an optical fiber guide tube 500 and a rock coupling component;

[0109] The deformable body 100 is cylindrical;

[0110] The protective shell 400 is disposed outside the deformable body 100, and the bottom of the vibration transmission component 300 is at least partially exposed outside the protective shell 400; the protective shell 400 is mainly used to protect the sensor components installed inside it and reduce the external interference of the integrated optical fiber sensor; the protective shell 400 is usually made of metal material, and it can be a variety of structures, usually a cylindrical or inverted frustum-shaped shell;

[0111] The optical fiber guide tube 500 includes an inner guide tube 510 and an outer guide tube 520; the inner guide tube 510 is inserted into the protective housing 400 along the axial direction of the deformable body 100; the outer guide tube 520 is arranged outside the protective housing 400, and a partial tube section thereof is opened and connected to one end of the inner guide tube 510;

[0112] The third optical fiber also includes an entry optical fiber segment 210 and an exit optical fiber segment 240; the tail end of the entry optical fiber segment 210 passes through the optical fiber guide tube 500 from one end of the outer guide tube 520, passes through the side of the inner guide tube 510, and is connected to the head end of the first optical fiber segment; the head end of the exit optical fiber segment 240 is connected to the tail end of the second optical fiber segment, and its tail end passes through the optical fiber guide tube 500 from the side of the inner guide tube 510, and passes through the other end of the outer guide tube 520.

[0113] The rock coupling component is arranged at the bottom of the vibration conduction component 300, and is used for coupling and connecting with the rock mass; the rock coupling component can be of various types, such as screws, bolts, anchor rods, connecting seats, etc.; the specific structure of the rock coupling component can be selected according to the cavern walls of different flatnesses to ensure that the integrated optical fiber sensor can be fully coupled with the cavern surrounding rock to achieve the best monitoring effect.

[0114] The fiber segment 210 entering and the fiber segment 240 exiting are usually packaged and protected by armor; the armor is usually made of corrosion-resistant and anti-aging materials, preferably made of rubber. The fiber guide tube 500, which is mainly composed of an inner guide tube 510 and an outer guide tube 520, is used for guiding the fiber to enter and exit, and conveniently optically connecting with other optical fibers and / or other integrated fiber sensors, and protecting this part of the fiber segment from external factors; the inner guide tube 510 is inserted into the protective shell 400 along the axial direction of the deformable body 100, so that the entire integrated fiber sensor structure is compact and convenient for the installation of the deformable body 100. The tail end of the fiber segment 210 entering is passed out from the side of the inner guide tube 510, so as to be directly connected to the first fiber segment wound on the deformable body 100; the tail end of the fiber segment 240 exiting is passed into the fiber guide tube 500 from the side of the inner guide tube 510, so as to be directly connected to the second fiber segment wound on the deformable body 100; in this way, the fiber segments used for connection can be reduced, which is conducive to improving the accuracy of monitoring. The exposed connection ends of the incoming optical fiber segment 210 and the outgoing optical fiber segment 240 are respectively passed through the two end pipe openings of the outer guide tube 520, so that the integrated optical fiber sensor can be connected with other optical components during use and is convenient for maintenance.

[0115] In some embodiments of the present invention, the bottom of the protective shell 400 is open, the deformable body 100 is disposed in the protective shell 400 and fixed in a compressed state between the inner top surface of the protective shell 400 and the vibration conduction component 300, and the exposed portion of the vibration conduction component 300 is exposed from the opening at the bottom of the protective shell 400.

[0116] For the vibration conduction component 300 mainly composed of a rigid conduction sheet 310 and a rigid vibration ball 320, when the rupture signal is transmitted to the rigid vibration ball 320, it will cause multiple uniformly distributed rigid vibration balls 320 to vibrate, and then the rigid vibration ball 320 will evenly distribute the rupture signal to the deformable body 100 through the rigid conduction sheet 310, thereby causing the deformable body 100 to produce a uniform deformation corresponding to the rupture signal, and the deformation of the deformable body 100 will cause the first optical fiber coil 220 and the second optical fiber coil 230 to deform, causing the optical signal inside the optical fiber to change, and finally the rupture signal will be restored, thereby realizing the monitoring of the rupture signal.

[0117] In order to further facilitate the use and maintenance of the integrated optical fiber sensor, Figure 2 , Figure 6 or Figure 7As shown, in some embodiments of the present invention, the inner guide tube 510 and the outer guide tube 520 are perpendicular to each other, and the middle tube section of the outer guide tube 520 is open and connected to one end of the inner guide tube 510 to form a "T"-shaped optical fiber guide tube 500.

[0118] For example Figure 6 As shown, in some embodiments of the present invention, the rock coupling component of the integrated optical fiber sensor is a coupling cone head 600, and the coupling cone head 600 is connected to the bottom of the vibration transmission component 300 through its bottom surface. The coupling cone head 600 has a conical structure, and its tip is convenient for inserting into the surrounding rock of the cave, and enables it to be fully coupled with the surrounding rock of the cave to effectively transmit the fracture signal; when the fracture signal is transmitted to the coupling cone head 600, it will cause the vibration transmission component 300 to vibrate. The integrated optical fiber sensor is particularly suitable for use in situations where the wall of the cave has a large undulation, such as: a cave excavated by blasting.

[0119] In order to further improve the monitoring effect, Figure 6 As shown, in some embodiments of the present invention, the coupling cone head 600 and the deformation body 100 remain coaxial.

[0120] For example Figure 7 As shown, in some embodiments of the present invention, the rock coupling component of the integrated optical fiber sensor includes a coupling base 710 and a coupling connector 720; one side surface of the coupling base 710 is attached to the bottom of the vibration conduction component 300; the coupling connector 720 is arranged on the coupling base 710, and at least part of its connection part passes through the other side surface of the coupling base 710; there are at least three coupling connectors 720, and they are distributed in a ring array with the extension line of the axis of the deformable body 100 as the array center line. The integrated optical fiber sensor is installed, supported and vibration-conducted by the coupling base 710, and is connected to the surrounding rock of the cavern by the coupling connector 720 so that the coupling base 710 is fully in contact with the rock mass, thereby enhancing the conduction of the fracture signal; the coupling connector 720 can be a screw, a bolt, etc. The integrated optical fiber sensor not only has a good coupling effect with the surrounding rock, but also requires a small depth of drilling the surrounding rock, and has a small installation difficulty. It is particularly suitable for caverns with relatively flat walls, such as caverns excavated by TBM (full-face hard rock tunnel boring machine).

[0121] The distributed optical fiber monitoring system for monitoring rock mass change state provided by the present invention is applied to an underground cavern 1, and can monitor fracture signals during construction and locate the fracture source and obtain the energy intensity of the source; the distributed optical fiber monitoring system has the advantages of simple deployment, long-distance monitoring, high sensitivity, large capacity, low-cost, all-weather, full-space sound wave / vibration perception, etc., and overcomes the problems of relatively scattered monitoring signals of a single bare optical fiber, great deployment difficulty, and low survival rate in complex geological environments. It can be used in complex deep buried complex environments, and effectively monitor fracture signals such as vibration and sound generated before and during the fracture, and can prevent and monitor rock fractures generated during the excavation of deep buried high-stress underground cavern projects, thereby ensuring the safe and smooth construction of deep underground projects.

[0122] The distributed optical fiber monitoring system for monitoring rock mass change status provided by the present invention has a spatial distance resolution as low as less than 1m, and can identify signal frequencies in the range of 1 to 2000Hz. Its capacity is determined by the multi-channel optical fiber sensor regulator 4. The internal storage can currently reach 4TB, and the external storage can be increased indefinitely, so long-term monitoring can be achieved.

[0123] The description of various embodiments of the present invention is presented herein for illustrative purposes only and is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terms used herein are selected to best explain the principles, practical applications, or technological advances of the embodiments, or to enable other persons skilled in the art to understand the embodiments disclosed herein, compared to the technology found on the market.

[0124] In this article, various embodiments of the present invention may be presented in the form of a range. It should be understood that the description in the form of a range is only for convenience and brevity, and should not be interpreted as a hard limit to the scope of the present invention. Therefore, the description of the range should be considered to specifically disclose all possible sub-ranges and individual numerical values ​​within the range. For example, the description of a range such as from 1 to 6 should be considered to specifically disclose sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and each numerical value within the range, such as 1, 2, 3, 4, 5, 6, which has nothing to do with the width of the range.

[0125] It should be understood that certain features of the invention described in the context of separate embodiments for the sake of clarity may also be provided in combination in a single embodiment. Conversely, various features of the invention described in the context of a single embodiment for the sake of brevity may also be provided individually or in any suitable sub-combination, or in any other described embodiment of the invention where appropriate. Certain features described in the context of various embodiments are not considered essential features of those embodiments unless the embodiments would not function without those features.

[0126] All publications, patents, and patent applications mentioned herein are incorporated herein by reference in their entirety, to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated as being incorporated herein by reference. In addition, the citation or identification of any reference herein should not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, the section headings should not be construed as necessarily limiting.

Claims

1. A distributed optical fiber monitoring system for monitoring rock mass change status, comprising a first optical fiber (2), wherein the first optical fiber (2) is arranged on a cavern wall (11) of an underground cavern (1) along the axial direction thereof; Features: It also includes a second optical fiber (3), wherein the second optical fiber (3) includes a peripheral optical fiber segment (31) and a switching transition segment (32); The peripheral optical fiber segment (31) is used to be arranged on the cave wall (11) along the cross-sectional profile thereof; There are at least two circumferential optical fiber segments (31) which can be arranged at intervals along the axial direction of the underground cavern (1). The circumferential optical fiber segments (31) are sequentially connected end to end via a switching transition segment (32) so that the optical path of the second optical fiber (3) is continuous.

2. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 1, characterized in that: The cavern wall (11) comprises a left cavern wall, a top cavern wall and a right cavern wall; There are three or more first optical fibers (2), at least one of which is arranged on the left wall of the cave, at least one of which is arranged on the top wall of the cave, and at least one of which is arranged on the right wall of the cave.

3. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 2, characterized in that: The number of the first optical fibers (2) is six; One of them is used to be laid on the left wall of the cavern and is located at 1 / 3 of the height of the left wall of the cavern; One of them is used to be laid on the left wall of the cavern and is located at 2 / 3 of the height of the left wall of the cavern; One of them is used to be laid on the top wall of the cavern and is located at a position of 1 / 3 of the arc length of the top wall of the cavern; One of them is used to be laid on the top wall of the cavern and is located at a position of 2 / 3 of the arc length of the top wall of the cavern; One of them is used to be laid on the right wall of the cavern and is located at 1 / 3 of the height of the right wall of the cavern; One of them is used to be laid on the right wall of the cavern and is located at 2 / 3 of the height of the right wall of the cavern.

4. The distributed optical fiber monitoring system for monitoring rock mass change status according to any one of claims 1 to 3, characterized in that: It also includes a multi-channel optical fiber sensor regulator (4) and a data processing terminal (5); One end of the first optical fiber (2) and the second optical fiber (3) are both used to extend to the excavation surface of the underground cavern (1), and are both provided with a light extinguisher; The other ends of the first optical fiber (2) and the second optical fiber (3) are optically connected to a multi-channel optical fiber sensor regulator (4) via an outgoing optical fiber that can be laid along the wall of the shaft; The multi-channel optical fiber sensing regulator (4) is communicatively connected to a data processing terminal (5).

5. The distributed optical fiber monitoring system for monitoring rock mass change state according to claim 4, characterized in that: The first optical fiber (2) and / or the second optical fiber (3) is optically connected to an integrated optical fiber sensor for collecting rupture signals in a key monitoring area; The integrated optical fiber sensor comprises a deformable body (100) and a third optical fiber, wherein the third optical fiber comprises a first optical fiber segment and a second optical fiber segment that are connected to each other; The first optical fiber segment is arranged on the peripheral wall of the deformable body (100) and is spirally wound at least once around the axial direction of the deformable body (100) to form a first optical fiber coil (220); The second optical fiber segment comprises a straight segment (231) arranged on the peripheral wall of the deformable body (100) along the axial direction thereof, the straight segment (231) being at least two and evenly distributed around the circumference of the deformable body (100), and the straight segments (231) being connected end to end in sequence via an arc-shaped reversing segment (232) to form a second optical fiber coil (230) with a continuous optical path.

6. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 5, characterized in that: The integrated optical fiber sensor further comprises a vibration conduction component (300); The vibration transmission component (300) is arranged at the bottom of the deformable body (100) and is used to transmit the vibration generated by the rock mass fracture to the deformable body (100).

7. The distributed optical fiber monitoring system for monitoring rock mass change state according to claim 6, characterized in that: The vibration conduction component (300) comprises a rigid conduction sheet (310) and a rigid vibration ball (320); One side surface of the rigid conductive sheet (310) is attached to the bottom surface of the deformable body (100); The rigid vibration balls (320) are arranged on the other side surface of the rigid conductive sheet (310). There are at least three rigid vibration balls (320) distributed in a ring array with the extension line of the axis of the deformable body (100) as the array center line.

8. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 6, characterized in that: The integrated optical fiber sensor also includes a protective housing (400), an optical fiber guide tube (500) and a rock mass coupling component; The deformable body (100) is cylindrical; The protective shell (400) is disposed outside the deformable body (100), and the bottom of the vibration conducting component (300) is at least partially exposed outside the protective shell (400); The optical fiber guide tube (500) comprises an inner guide tube (510) and an outer guide tube (520); the inner guide tube (510) is inserted into the protective outer shell (400) along the axial direction of the deformable body (100); the outer guide tube (520) is arranged outside the protective outer shell (400), and a partial tube section thereof is opened and connected to a tube opening at one end of the inner guide tube (510); The third optical fiber also includes an entry optical fiber segment (210) and an exit optical fiber segment (240); the tail end of the entry optical fiber segment (210) penetrates into the optical fiber guide tube (500) from one end of the outer guide tube (520), and passes out from the side of the inner guide tube (510), and is connected to the head end of the first optical fiber segment; the head end of the exit optical fiber segment (240) is connected to the tail end of the second optical fiber segment, and the tail end thereof penetrates into the optical fiber guide tube (500) from the side of the inner guide tube (510), and passes out from the other end of the outer guide tube (520); The rock mass coupling component is arranged at the bottom of the vibration conduction component (300) and is used for coupling connection with the rock mass.

9. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 8, characterized in that: The rock mass coupling component is a coupling cone head (600), and the coupling cone head (600) is connected to the bottom of the vibration conduction component (300) through its bottom surface.

10. The distributed optical fiber monitoring system for monitoring rock mass change status according to claim 8, characterized in that: The rock mass coupling component comprises a coupling base (710) and a coupling connector (720); One side surface of the coupling base (710) is attached to the bottom of the vibration conduction component (300); The coupling connector (720) is arranged on the coupling base (710), and at least part of its connecting portion passes through the other side surface of the coupling base (710); The coupling connectors (720) are at least three and are distributed in a ring array with the extension line of the axis of the deformable body (100) as the array center line.

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