Surrounding rock transparent stress field optical fiber anchor cable testing device and method

Abstract

The invention provides a surrounding rock transparent stress field optical fiber anchor cable testing device and method, and particularly relates to the field of mine mining safety testing, and the device comprises an anchoring assembly, a sealing part, an optical fiber sensor and a fixing protection part; the anchoring assembly is fixed in surrounding rock; the sealing component is of a tubular closed structure and is tightly attached to the outer wall of the anchoring assembly. The optical fiber sensor is arranged in the anchoring assembly in a penetrating manner and comprises a distributed optical fiber and an optical fiber grating, and the distributed optical fiber is spirally wound and annularly arranged along the outer wall of the anchoring assembly and is folded and placed in the anchoring assembly when wound to the tail end of an anchoring section of the anchoring assembly; the fiber bragg grating is radially arranged in the anchoring assembly; the fixed protection parts are tightly attached to the anchoring section and the exposed section of the outer wall of the anchoring assembly respectively, and the sealing part is clamped between the fixed protection parts; the surrounding rock stress field can be accurately tested in a large range, and the problems of low sensitivity, large error and limited test range during surrounding rock stress test in the prior art are solved.

Description

Technical Field

[0001] The invention relates to the field of mine mining safety testing, and in particular to a surrounding rock transparent stress field optical fiber anchor cable testing device and method. Background Art

[0002] In recent years, with the development of technology, the depth of underground mining has gradually increased, and the stress of the surrounding rock of coal mine tunnels has also increased significantly. When the surrounding rock stress exceeds the bearing capacity of the rock, it will cause the rock to become unstable, deform, crack, or even collapse, making it difficult to support deep tunnels, and bringing major safety issues to the development of deep mineral resources. On the other hand, in the process of mineral resource mining, as the mining work progresses, the surrounding rock stress field will be redistributed, and the occurrence of significant changes will intensify the stress concentration in certain areas, thereby increasing the risk of tunnel instability and collapse.

[0003] At present, the commonly used methods for monitoring tunnel surrounding rock stress mainly include borehole stress monitoring technology, electromagnetic radiation monitoring technology and microseismic monitoring technology. Borehole stress monitoring technology can only measure the local stress field around the borehole, and the borehole will cause certain damage to the rock mass, which may cause stress redistribution in the surrounding rock and affect the monitoring results; the electromagnetic radiation signal of electromagnetic radiation monitoring technology will attenuate during the propagation process, affecting the measurement accuracy and signal strength; microseismic monitoring technology is difficult to achieve comprehensive monitoring in a large area, and requires multiple monitoring points to work together.

[0004] In view of the above problems, how to improve the sensitivity of surrounding rock stress testing, enhance anti-interference ability and expand the detection range while reducing the disturbance to the surrounding rock is a problem that needs to be solved at present. Summary of the invention

[0005] The main purpose of the present invention is to provide a surrounding rock transparent stress field optical fiber anchor cable testing device and method to solve the problems of low sensitivity, large error and limited testing range when testing surrounding rock stress in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, there is provided a surrounding rock transparent stress field fiber optic anchor cable testing device, comprising: an anchoring assembly, the anchoring assembly is fixed inside the surrounding rock; a sealing component, the sealing component is a tubular closed structure, and the sealing component is tightly fitted on the outer wall of the anchoring assembly; an optical fiber sensor, the optical fiber sensor is arranged throughout the interior of the anchoring assembly, the optical fiber sensor comprises a distributed optical fiber and an optical fiber grating, the distributed optical fiber is spirally wound along the outer wall of the anchoring assembly and arranged circumferentially, and when it reaches the end of the anchoring section of the anchoring assembly, it is folded and placed inside the anchoring assembly, and the distributed optical fiber is used to perform stress testing on the entire length area of ​​the surrounding rock; the optical fiber grating is radially arranged inside the anchoring assembly; a fixed protective component, the fixed protective components are respectively tightly arranged on the anchoring section and the exposed section of the outer wall of the anchoring assembly, and the sealing component is sandwiched in the middle of the fixed protective component; wherein the sealing component is used to prevent slurry from entering the interior of the anchoring assembly, and the fixed protective component is used to protect the two ends and the interior of the anchoring assembly from being affected by external forces during installation and use.

[0007] Furthermore, the anchoring assembly includes: an anchor rod body, which is a hollow rod-shaped structure in the shape of a cylinder; a grouting pipe, which is arranged along the anchor rod body and passes through a grouting section arranged on the anchor rod body; wherein the anchor rod body is used to provide main structural support, the grouting pipe is used to pour grout into the surrounding rock, and the grouting hole is used to evenly distribute the slurry.

[0008] Furthermore, the sealing component includes: a slurry stop plug, which is annular and located at the position where the grouting section of the anchor rod body abuts against the tray; a rubber layer, which is a closed structure, and the rubber layer is arranged from one side of the slurry stop plug to the end of the anchoring section of the anchor rod body, and the rubber layer is circumferentially sleeved along the anchor rod body and tightly fits the outside of the grouting pipe; wherein the slurry stop plug is used to prevent the slurry from leaking along the outside of the anchor rod body, and the rubber layer is used to provide additional sealing protection to prevent external impurities from entering the interior of the anchor assembly.

[0009] Furthermore, the optical fiber sensor also includes: a steel pipe, which is arranged through the interior of the anchor rod body; wherein the distributed optical fiber is spirally wound along the outer wall of the anchor rod body and arranged in an annular direction, and when it is wound from one side of the grouting section stop plug to the anchor section of the anchor rod body, it is folded and placed in the steel pipe inside the anchor rod body; the optical fiber Bragg grating is arranged radially inside the anchor rod body and placed in the steel pipe; after the distributed optical fiber and optical fiber Bragg grating are arranged through the steel pipe, they are tested by connecting the test equipment; the distributed optical fiber is used to perform stress testing on the entire length of the surrounding rock, and the optical fiber Bragg grating is used to perform stress testing on the area within two meters of the anchor assembly.

[0010] Furthermore, the fixed protection component includes: a lock, which is fixed on the outer wall of the exposed section of the anchor rod body; a tray, which is in the shape of a flat plate and is located between the exposed section and the grouting section of the anchor rod body and close to the lock; a guide cap, which is located at the end of the anchoring section of the anchor rod body and is conical; a metal guide head, which is arranged on the outside of the anchoring section of the anchor rod body and is used to protect the ends of the distributed optical fiber and the optical fiber grating; wherein the lock is used to ensure the fixation and stability of the anchor assembly at the installation position to prevent it from displacement or loosening during use, the tray is used to increase the fixing area of ​​the anchor rod body to disperse the stress on the anchor cable, the guide cap is used to guide the anchor rod body into the surrounding rock to reduce the resistance during installation, and the metal guide head is used to ensure that the sensor end is not damaged during installation and use.

[0011] According to another aspect of the present invention, a method for testing a surrounding rock transparent stress field optical fiber anchor cable is provided. The method is implemented based on a surrounding rock transparent stress field optical fiber anchor cable testing device, and the method comprises the following steps:

[0012] Step S1: installing prefabricated fixed anchor rods in the surrounding rock using an anchor cable support technology;

[0013] Step S2: obtaining a surrounding rock transparent stress field optical fiber anchor cable test device, the surrounding rock transparent stress field optical fiber anchor cable test device comprising: an optical fiber sensor, the optical fiber sensor comprising: a distributed optical fiber, an optical fiber Bragg grating, laying out the surrounding rock transparent stress field optical fiber anchor cable test device between the installed fixed anchor rods, the surrounding rock transparent stress field optical fiber anchor cable test device is installed with an optical fiber sensor, wherein the optical fiber sensor comprises a distributed optical fiber and an optical fiber Bragg grating, the optical fiber anchor cable is obtained by installing the optical fiber Bragg grating on the fixed anchor rod, and the distributed optical fiber is laid out between the optical fiber anchor cable and the fixed anchor rod to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device;

[0014] Step S3: connecting the optical fiber sensor in the surrounding rock transparent stress field optical fiber anchor cable test device to the test equipment and performing initialization and parameter setting to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device;

[0015] Step S4: Use the surrounding rock transparent stress field optical fiber anchor cable testing device to perform testing and analyze the results.

[0016] Further, step S1 includes:

[0017] Step S101: pre-drilling a hole in the rock mass by using a drilling machine or blasting;

[0018] Step S102: sending the prefabricated fixed anchor rod into the rock mass through the drilling hole;

[0019] Step S103: Apply tension to the end or fixed point of the fixed anchor rod to strengthen the fixed anchor rod.

[0020] Further, step S2 includes:

[0021] Step S201: making an optical fiber anchor cable. The surrounding rock transparent stress field optical fiber anchor cable testing device also includes: an anchor cable rod body and a steel pipe. The optical fiber anchor cable is obtained by embedding the steel pipe in the anchor cable rod body and inserting the optical fiber Bragg grating into the steel pipe.

[0022] Step S201: replacing the original fixed anchor cable with an optical fiber anchor cable in the middle of the top plate of the working face, where the top plate of the working face is the surrounding rock above the working face;

[0023] Step S202: installing optical fiber anchor cables on the non-mining side of the working face, where the non-mining side of the working face is the surrounding rock on the side that has not been mined;

[0024] Step S203: installing an optical fiber anchor cable on the mining side of the working face, where the mining side of the working face is the surrounding rock on one side for mining;

[0025] Step S204: Install the distributed optical fiber by pre-embedding or drilling.

[0026] Further, step S3 includes:

[0027] Step S301: Connect the output end of the optical fiber sensor to the test equipment and perform signal debugging;

[0028] Step S302: Start the test equipment, set the sampling rate and test range for initialization;

[0029] Step S303: adjusting the sampling rate and sensitivity according to the test requirements to complete the setting of the test parameters.

[0030] Further, step S4 includes:

[0031] Step S401: Start the surrounding rock transparent stress field optical fiber anchor cable testing device and data acquisition program to start testing, monitor the changes of optical fiber sensor signals in real time, and record the data;

[0032] Step S402: filtering and denoising the collected data;

[0033] Step S403: Analyze and evaluate the environmental parameters according to the test data, obtain the change rules and trends of the environmental parameters through the changes in temperature, pressure and strain, and take measures to deal with them;

[0034] Step S405: Display the test data in an intuitive form of charts or curves to present the changing trends and rules of the test parameters, and summarize and analyze the test results to generate a test report.

[0035] The surrounding rock transparent stress field optical fiber anchor cable testing device of the technical solution of the present invention comprises an anchoring assembly, a sealing component, an optical fiber sensor, and a fixed protective component; the anchoring assembly is fixed inside the surrounding rock; the sealing component is a tubular closed structure, and the sealing component is tightly fitted on the outer wall of the anchoring assembly; the optical fiber sensor is arranged throughout the interior of the anchoring assembly, and the optical fiber sensor comprises a distributed optical fiber and an optical fiber grating, the distributed optical fiber is spirally wound and arranged circumferentially along the outer wall of the anchoring assembly, and is folded and placed inside the anchoring assembly when it reaches the end of the anchoring section of the anchoring assembly; the optical fiber grating is radially arranged inside the anchoring assembly; the fixed protective components are respectively tightly arranged on the anchoring section and the exposed section of the outer wall of the anchoring assembly, and the sealing component is sandwiched in the middle of the fixed protective components; thereby, when testing the surrounding rock stress, the sensitivity of the surrounding rock stress test is improved, the anti-interference ability is enhanced, and the detection range is expanded while reducing the disturbance to the surrounding rock. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0037] Figure 1 It is a structural schematic diagram of an optional surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention;

[0038] Figure 2 It is a longitudinal cross-sectional view of an optional surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention;

[0039] Figure 3 is a cross-sectional view of an optional surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the layout of a tunnel optical fiber anchor cable 50 of an optional surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention;

[0041] Figure 5 It is a schematic diagram of the layout of the optical fiber anchor cable 50 on the top of a tunnel of a surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the layout array of optical fiber anchor cables 50 of an optical fiber anchor cable testing device for transparent stress field of surrounding rocks, which can be selected according to an embodiment of the present invention;

[0043] Figure 7 The present invention is a flowchart of an optional surrounding rock transparent stress field optical fiber anchor testing method according to an embodiment of the present invention.

[0044] The above drawings include the following reference numerals:

[0045] 10. Anchoring assembly; 11. Anchor rod body; 111. Exposed section; 112. Grouting section; 113. Anchoring section; 12. Grouting pipe; 20. Sealing component; 21. Grouting plug; 22. Rubber layer; 30. Fiber optic sensor; 31. Distributed optical fiber; 32. Fiber Bragg grating; 33. Steel pipe; 40. Fixed protection component; 41. Lock; 42. Tray; 43. Guide cap; 44. Metal guide head. DETAILED DESCRIPTION

[0046] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0047] The present invention provides a surrounding rock transparent stress field optical fiber anchor cable testing device, such as Figure 1 and Figure 2 As shown, it includes: an anchoring component 10, a sealing component 20, an optical fiber sensor 30, and a fixed protective component 40; the anchoring component 10 is fixed inside the surrounding rock; the sealing component 20 is a tubular closed structure, and the sealing component 20 is tightly fitted on the outer wall of the anchoring component 10; the optical fiber sensor 30 is arranged inside the anchoring component 10 through and through, and the optical fiber sensor 30 includes a distributed optical fiber 31 and an optical fiber grating 32, the distributed optical fiber 31 is spirally wound along the outer wall of the anchoring component 10 and is arranged circumferentially, and is folded and placed inside the anchoring component 10 when it reaches the end of the anchoring section 113 of the anchoring component 10; the optical fiber grating 32 is radially arranged inside the anchoring component 10; the fixed protective component 40 is respectively tightly fitted on the anchoring section 113 and the exposed section 111 of the outer wall of the anchoring component 10, and the sealing component 20 is sandwiched between the fixed protective component 40; so that when testing the surrounding rock stress, the sensitivity of the surrounding rock stress test is improved, the anti-interference ability is enhanced, and the detection range is expanded while reducing the disturbance to the surrounding rock.

[0048] Furthermore, the anchor assembly 10 includes: an anchor rod body 11, which is a hollow rod-shaped structure in the shape of a cylinder; a grouting pipe 12, which is arranged along the anchor rod body 11 and passes through a grouting section 112 arranged on the anchor rod body 11; wherein the anchor rod body 11 is used to provide main structural support, and the grouting pipe 12 is used to pour grout into the surrounding rock to enhance the strength and stability of the anchoring. Small circular grouting holes are arranged in parallel at equal intervals on one side of the grouting section 112 of the anchor rod body 11, and the number of the grouting holes is greater than two, which is used to evenly distribute the slurry to ensure that each part of the anchoring section 113 can be fully reinforced by the grouting material, thereby improving the anchoring effect.

[0049] Furthermore, the sealing component 20 includes: a slurry stop plug 21, which is annular and located at the position where the grouting section 112 of the anchor rod body 11 abuts against the tray 42; a rubber layer 22, which is a closed structure, and the rubber layer 22 is arranged from one side of the slurry stop plug 21 to the end of the anchoring section 113 of the anchor rod body 11, and the rubber layer 22 is circumferentially sleeved along the anchor rod body 11 and tightly fits the outside of the grouting pipe 12; wherein the slurry stop plug 21 is used to prevent the slurry from leaking along the outside of the anchor rod body 11, prevent the slurry from flowing back during the grouting process, and ensure that the slurry can be concentrated in the grouting section 112, and the rubber layer 22 is used to provide additional sealing protection to prevent external moisture and impurities from entering the interior of the anchor assembly 10. At the same time, the buffering effect of the rubber layer 22 can absorb mechanical vibrations, protect the grouting pipe 12 and the optical fiber from external impact, and ensure the stability of the internal environment of the device.

[0050] Furthermore, if Figure 2 and Figure 3 As shown, the optical fiber sensor 30 also includes: a steel pipe 33, which is arranged inside the anchor rod body 11; wherein the distributed optical fiber 31 is arranged in a 45° spiral winding circumferential direction along the outer wall of the anchor rod body 11. To ensure that the distributed optical fiber 31 is in close contact with the surface of the anchor rod body 11, a flame-retardant cable tie is used to tie and fix the optical cable on the surface of the anchor rod body 11 at a certain interval, and the cable tie position is tied and wrapped with a waterproof tape for secondary fixation. When the distributed optical fiber 31 is removed from the grouting section 112, the grouting plug When the position on one side of 21 is wrapped around to the anchoring section 113 of the anchor rod body 11, it is folded and placed in the steel pipe 33 inside the anchor rod body 11; the fiber grating 32 is arranged radially inside the anchor rod body 11 and placed in the steel pipe 33; after the distributed optical fiber 31 and the fiber grating 32 are laid through the steel pipe 33, they are tested by connecting the test equipment; the distributed optical fiber 31 is used to perform stress testing on the entire length of the surrounding rock, and the fiber grating 32 is used to perform stress testing on the area within two meters of the anchor assembly 10.

[0051] Specifically, the advantages of the distributed optical fiber 31 being spirally wound and laid out in an annular direction along the outer wall of the anchor cable rod body 11 are mainly reflected in the following aspects: (1) Comprehensive monitoring. The distributed optical fiber 31 covers the entire surface of the anchor cable rod body 11 through spiral winding, and can capture stress and strain information in all directions, provide all-round monitoring of the surrounding environment of the anchor cable rod body 11, and can monitor more comprehensive data under complex stress conditions. (2) Improved sensitivity. The spiral winding method increases the path length of the distributed optical fiber 31. Compared with the horizontal layout, the contact area between the distributed optical fiber 31 and the surrounding rock is larger, and the response to local deformation and stress concentration inside the surrounding rock is more sensitive. (3) Enhanced damage resistance. The spiral winding layout can evenly distribute external forces and reduce the damage to the distributed optical fiber 31 caused by local stress concentration. Compared with the horizontal layout, this layout reduces the risk of failure of the entire optical fiber due to local damage, and improves the reliability and durability of the system. (4) Anti-interference ability. The spiral winding method reduces the impact of environmental noise and external interference on the signal of the distributed optical fiber 31. In complex underground or high-pressure environments, the spirally wound distributed optical fiber 31 can transmit signals more stably and provide more accurate measurement results. (5) Uniform strain distribution. The strain distribution experienced by the spirally wound distributed optical fiber 31 is more uniform, avoiding the strain concentration phenomenon that may occur in horizontal layout, and can obtain a more realistic stress state, thereby improving the credibility of the data. (6) Adaptability to complex shapes and environments. The spiral winding method better adapts to the changing geological conditions such as the irregular morphological structure of the anchor rod body 11 and its surrounding environment, while horizontal layout is difficult to maintain close contact or stability in complex environments. (7) Signal redundancy and stability. Spiral winding provides multi-path signal redundancy. Even if the distributed optical fiber 31 is partially damaged, the other parts can still work normally, maintaining the continuity and stability of monitoring.

[0052] Specifically, the distributed optical fiber sensing technology has high test accuracy and resolution, can realize the physical quantity measurement of the optical fiber position, and can realize the real-time measurement of the physical quantity distribution within the entire optical fiber length range, and has high sensitivity and response speed for small physical quantity changes. The principle of the distributed optical fiber 31 is the stimulated Brillouin light time domain scattering technology in the distributed optical fiber sensing technology, which can well perform the full-length stress test of the surrounding rock and judge and analyze the surrounding rock damage.

[0053] Furthermore, stimulated Brillouin optical time-domain scattering technology uses optical fiber as a sensing element. When the optical fiber under test is subjected to external force or temperature changes, backward stimulated Brillouin scattering excites longitudinal sound waves in the optical fiber. A Brillouin frequency shift will be generated between the scattered light and the incident light. By measuring the change in the Brillouin frequency shift, the changes in temperature and stress to which the surrounding rock is subjected can be analyzed.

[0054] The change in Brillouin frequency shift with temperature and strain is:

[0055] Δε=[ΔV B -C1ΔT] / C2

[0056] Where Δε is the strain change; ΔV B is the Brillouin frequency shift, MHz; C1 is the temperature sensitivity coefficient, MHz / ℃; ΔT is the temperature change, ℃; C2 is the strain sensitivity coefficient, 103GHz. For single-mode optical fiber, the temperature and stress coefficients are approximately 1.07MHz / ℃ and 0.05MHz / με, respectively. Therefore, by measuring the Brillouin frequency shift distribution along the optical fiber, it is possible to perform distributed testing of temperature and stress.

[0057] Figure 4 This is a schematic diagram of the layout of optical fiber anchor cables 50 in a tunnel according to an optional surrounding rock transparent stress field optical fiber anchor cable testing device according to an embodiment of the present invention. 27 optical fiber anchor cables 50 are laid in the tunnel surrounding rock and are interconnected by distributed optical fibers 31, wherein a 3×3 optical fiber anchor cable array is arranged on the tunnel roof, mining side, and non-mining side.

[0058] Figure 5 The present invention is a schematic diagram of the layout of the optical fiber anchor 50 on the top plate of a tunnel according to an optional surrounding rock transparent stress field optical fiber anchor testing device according to an embodiment of the present invention. Taking the layout of the optical fiber anchor 50 on the top plate of the tunnel as an example, in the 3×3 optical fiber anchor 50 array, the horizontal spacing of each optical fiber anchor 50 is 1600mm, and the vertical spacing is 1000mm, ensuring that the measuring points cover the key areas of the surrounding rock of the entire tunnel.

[0059] Figure 6 The present invention is a schematic diagram of an array arrangement of optical fiber anchor cables 50 of an optical fiber anchor cable testing device for transparent stress field of surrounding rocks which can be selected according to an embodiment of the present invention. When specifically arranged, the lower left corner of the tunnel is taken as the origin, the length direction of the tunnel is taken as the x-axis, the width direction of the tunnel is taken as the y-axis, and the optical fiber anchor cables 50 are arranged from 1200 mm away from the edge of the tunnel. The horizontal spacing between each optical fiber anchor cable 50 is 1600 mm, and the vertical spacing is 1000 mm.

[0060] Furthermore, the surrounding rock stress values ​​obtained by using the distributed optical fiber 31 are independent and discrete in the spatial range. When the measurement data is limited, the spatial interpolation method can be used to construct a continuous spatial data surface. To achieve this goal, the patent design uses the Kriging interpolation method to reconstruct the surrounding rock stress field. To perform Kriging interpolation on the monitoring data of the optical fiber anchor cable 50, the following conditions need to be met: First, the spatial distribution of the data should have sufficient density and coverage to effectively capture the spatial variability. Secondly, the data needs to show spatial correlation, which is usually verified by the semivariogram. In addition, it is necessary to select a suitable interpolation model (such as a spherical model, a Gaussian model or an exponential model), and estimate the model parameters, such as the base, the nugget and the range. Finally, the interpolation results need to be cross-validated to ensure the prediction accuracy and reliability of the model. This method comprehensively considers the positional relationship between the estimated point and the known point and the spatial correlation, and organically combines the time and space characteristics of the measured data and the data to be estimated during the interpolation process, with higher estimation accuracy.

[0061] Since the true value Z of any domain V to be estimated V The estimated value of Z* K , is a linear combination of n known sample values ​​Zi in the estimated neighborhood, Z i (i=1, 2, 3, ..., n):

[0062]

[0063] In the formula, k i is the weighting factor.

[0064] Therefore, samples Z within the region V should be obtained k , so that Z* K Become Z k The unbiased estimator of .

[0065] Assume that Z(x) satisfies the second-order stationary assumption:

[0066] E(Z k )=E(Z * K )=m

[0067] From the above two formulas, we can get:

[0068]

[0069] Therefore, the conditions for the second-order stationary assumption to hold are:

[0070]

[0071] Estimate Z* within a region V K Should meet:

[0072] [k]×[A]=[B]

[0073] The variogram simulation represents the simulation of the relationship between the positions of the samples. It can be used to represent the changes measured by the segmentation distance and estimate the new position. The variogram also plays this role. Its size can represent the degree of spatial variation of the regionalized variable caused by different distances.

[0074]

[0075] In the formula, γ* is the experimental variogram, h is the separation distance, which represents the distance between two variogram points, and N represents the number of paired sample points. * (h) is different. With the help of the actual measured samples, the corresponding variation function can be obtained.

[0076] The Kriging interpolation method is used, and the known points are selected dynamically. Since the range of known points involved in the interpolation calculation is dynamically changing, the specific method is to take the estimation accuracy control as the goal, use the error comparison results for feedback optimization, and select the measurement values ​​in different ranges for estimation. When the distance between the distributed optical fiber and the fiber Bragg grating and the estimated point is the same, a greater weight is assigned to the measurement data of the fiber Bragg grating. Through this dynamic selection method, the high precision of the fiber Bragg grating and the high density of the distributed optical fiber can be effectively combined to improve the accuracy of the overall test.

[0077] Select the measured values ​​in the valuation area to interpolate the valuation points, and you can get the matrix data about the interpolation points:

[0078]

[0079] Specifically, the principle of the fiber Bragg grating 32 is the fiber Bragg grating technology, which is an optical sensing technology based on optical fiber, used to realize the modulation, filtering, beam splitting and other functions of optical signals. It utilizes the periodic structure in the optical fiber and changes the refractive index distribution or periodic structure in the optical fiber to realize the processing and control of the optical signal, and has the advantages of high sensitivity, fast response speed, strong anti-interference and the like.

[0080] Furthermore, the fiber Bragg grating technology creates a periodic refractive distribution in the fiber core through ultraviolet light exposure technology. This periodic refractive index distribution forms a grating structure. Since the fiber Bragg grating 32 has selective reflection of light of a specific wavelength, when the external environment temperature or stress of the fiber Bragg grating 32 changes, it will cause the grating area length or effective refractive index of the fiber Bragg grating 32 to change, thereby causing the central reflection wavelength of the fiber Bragg grating to shift. By measuring the shift of the central reflection wavelength of the fiber Bragg grating 32, the changes in external temperature and stress can be reflected.

[0081] Fiber Bragg grating technology uses the characteristic of grating reflecting light of specific wavelength to realize sensing test. When broadband light is incident on the optical fiber, the grating will reflect the spectrum of specific wavelength. The central wavelength value of the reflected light is λ B There is a linear relationship between the axial strain and temperature of the grating:

[0082]

[0083] Among them, λ B is the initial center wavelength of the reflected light; Δλ B is the center wavelength drift; Δε and ΔT are the strain and temperature changes of the grating respectively; K ε , K T They are the strain and temperature calibration coefficients of the grating respectively. For quartz material, its K ε ≈0.784, K T ≈6.67×10 -6 .

[0084] In specific implementation, the distributed optical fiber 31 can test the stress of the entire length of the surrounding rock, achieving comprehensive coverage of the entire detection area. The detection results of the distributed optical fiber 31 can be reflected in real time, and abnormal situations can be discovered and handled in a timely manner. The fiber grating 32 is sensitive to stress changes and can achieve high-precision stress testing 1 to 2 meters near the anchor cable. The fiber grating 32 has a very fast response speed and is highly resistant to external interference such as electromagnetic interference. The distributed optical fiber 31 and the fiber grating 32 work together as the optical fiber sensor 30, which can detect tiny deformations and strains and simultaneously test multiple parameters such as temperature, strain, and stress, providing comprehensive test information. Furthermore, the fixed protection component 40 includes: a lock 41, which is fixed to the outer wall of the exposed section 111 of the anchor cable rod body 11; a tray 42, which is in the shape of a flat plate and is located between the exposed section 111 and the grouting section 112 of the anchor cable rod body 11 and close to the lock 41; a guide cap 43, which is located at the end of the anchoring section 113 of the anchor cable rod body 11 and is conical; a metal guide head 44, which is arranged on the outside of the anchoring section 113 of the anchor cable rod body 11 and is used to protect the distributed optical fiber 31 and the optical fiber 31. The end of the grating 32; wherein, the lock 41 is used to ensure that the anchor assembly 10 is fixed and stable at the installation position to prevent it from being displaced or loosened during use; the tray 42 increases the close contact area between the anchor rod body 11 and the surrounding rock, has a strong bearing capacity, is used to evenly distribute the load to disperse the stress on the anchor cable, and increases the stability of the anchor rod body 11; the guide cap 43 is used to guide the anchor rod body 11 into the surrounding rock to reduce the resistance during installation; the metal guide head 44 is used to ensure that the sensor end is not damaged during installation and use.

[0085] Specifically, the fiber grating 32 is a 1m fixed-point fiber grating, which engraves the fiber grating 32 with different central wavelengths on the same optical fiber, and packages the fiber grating 32 device into a 1m fixed-point grating cable. This 1m fixed-point grating cable has the advantages of dense distribution, less leads, and one-time simultaneous collection. The cable isolates the fiber core from the outside world through an empty tube with a diameter equivalent to the fiber core. The cable is buried in a steel pipe 33 and packaged with epoxy resin and a curing agent. After being subjected to lateral pressure, the packaging material and the inner layer of the optical fiber will be squeezed and contacted, so that the spatial fine-scale deformation can be measured, and some large deformations can also be shared, so as to achieve the purpose of measuring discontinuous large deformations.

[0086] Specifically, the use of a 1m fixed-point fiber Bragg grating 32 arranged inside the anchor rod body 11 has the following advantages: (1) Enhanced protection. The fiber Bragg grating 32 arranged inside the anchor rod body 11 is wrapped and protected by the anchor material, effectively avoiding mechanical damage, chemical corrosion, wear and tear from the external environment, and extending the service life of the fiber Bragg grating 32. (2) Reduced environmental interference. The internal arrangement makes the fiber Bragg grating 32 away from external environmental interference (such as temperature, humidity changes and mechanical vibration, etc.), and can provide stable and accurate measurement data even under complex or harsh environmental conditions. (3) Accurately monitor internal stress. The interior of the anchor rod body 11 is the main area of ​​force transmission. The fiber Bragg grating 32 arranged inside the anchor rod body 11 can more directly and accurately monitor the stress changes and deformation inside the surrounding rock, and provide more realistic stress state data. (4) Reduced signal attenuation. The fiber Bragg grating 32 arranged inside is closer to the stress source, and the signal transmission path is shorter, resulting in less signal attenuation and noise interference, thereby improving the signal quality and data accuracy. (5) Integration and concealment: The fiber Bragg grating 32 is built into the anchor rod body 11. Compared with the fiber optic cable laid on the outside, it avoids installation troubles and space occupation, and also improves the concealment of the entire system, making the monitoring device less susceptible to human damage. (6) Enhanced system reliability: The internal layout reduces the exposed area of ​​the fiber Bragg grating 32, reduces the impact of the external environment and human operation on the fiber, and thus improves the overall reliability of the monitoring system.

[0087] Furthermore, the distributed optical fiber 31 spirally wound around the outer surface of the anchor rod body 11 is combined with the fixed-point optical fiber Bragg grating 32 arranged inside the anchor rod body 11. Compared with the traditional single arrangement method, it has the following significant advantages: (1) All-round monitoring capability. The external spirally wound distributed optical fiber 31 covers the surface of the anchor rod body 11 and can provide continuous strain data. The internal optical fiber Bragg grating 32 accurately monitors the stress and strain of the core area and more accurately reflects the internal stress conditions. (2) Improving monitoring accuracy and reliability. By combining the external spiral winding arrangement of the distributed optical fiber 31 and the internal arrangement of the fixed-point optical fiber Bragg grating 32, the stress and strain information inside and outside the anchor cable can be obtained simultaneously. The distributed optical fiber 31 provides continuous data and the optical fiber Bragg grating 32 provides high-precision data. They complement each other and comprehensively evaluate the state of the anchor cable. (3) Improving the durability and protection of the system. The internal optical fiber Bragg grating 32 is wrapped by the anchor cable material, which has strong protection, avoids the influence of external factors such as mechanical damage and chemical corrosion, and prolongs the service life. The external spirally wound distributed optical fiber 31 disperses stress, reduces the risk of damage, and improves durability. (4) Multifunctional integrated design, external distributed optical fiber 31 monitors overall strain, and internal fiber Bragg grating 32 provides key parts data, taking into account both high-precision and large-scale monitoring. Flexible customized monitoring to adapt to different engineering scenarios. (5) Improve the value of data analysis, internal and external joint analysis, by simultaneously obtaining stress and strain data inside and outside the anchor rod body 11, better identify potential dangers and stress concentration areas, accurately judge the health status of the anchor, and combine internal and external monitoring methods to adapt to complex stress environments and provide accurate force distribution analysis.

[0088] Furthermore, the two optical fiber sensing technologies of distributed optical fiber 31 and optical fiber grating 32 are combined with the anchor cable support technology of underground engineering to form the optical fiber intelligent anchor cable technology. By embedding the optical fiber sensor in the anchor cable, the real-time monitoring and intelligent management of the underground engineering are realized. In actual monitoring, the optical fiber intelligent anchor cable technology continuously monitors the displacement and strain changes of each arrangement point, detects the stress field distribution of the surrounding rock during the mining process, and reconstructs the surrounding rock stress field monitoring data using the Kriging interpolation method. This method helps to improve the monitoring accuracy, especially when the surrounding rock of the tunnel is strained, the corresponding stress value distribution can be obtained by the change amount of the coordinate point, so as to accurately predict the change trend of the surrounding rock stress field and ensure the safety and stability of the underground engineering. The optical fiber intelligent anchor cable system of the present invention can significantly improve the accuracy and real-time performance of surrounding rock stress monitoring. The optical fiber intelligent anchor cable system can maintain stable operation in harsh environments, and provide accurate stress field distribution data through large-scale multi-point monitoring and Kriging interpolation calculation, thereby providing reliable technical support for the design, construction and maintenance of underground engineering.

[0089] Figure 7is a flow chart of a method for testing a fiber optic anchor cable in a transparent stress field of a surrounding rock, which can be selected according to an embodiment of the present invention. The present invention also provides a method for testing a fiber optic anchor cable in a transparent stress field of a surrounding rock, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the method includes:

[0090] Step S1: installing prefabricated fixed anchor rods in the surrounding rock using an anchor cable support technology;

[0091] Among them, the anchor cable support technology has the advantages of simple structure, convenient construction, and wide application range. The anchor rod and the anchor cable are connected to form a stable support system. The fixed anchor rod pre-buried in the surrounding rock is used to transmit the anchor cable tension, thereby enhancing the stability of the surrounding rock and reducing the deformation and collapse of the surface or underground space. The fixed anchor rod is made of high-strength steel.

[0092] Step S2: obtaining a surrounding rock transparent stress field optical fiber anchor cable test device, the surrounding rock transparent stress field optical fiber anchor cable test device comprising: an optical fiber sensor 30, the optical fiber sensor 30 comprising: a distributed optical fiber 31, an optical fiber grating 32, the surrounding rock transparent stress field optical fiber anchor cable test device is arranged between the installed fixed anchor rods, the surrounding rock transparent stress field optical fiber anchor cable test device is installed with the optical fiber sensor 30, wherein the optical fiber sensor 30 comprises the distributed optical fiber 31 and the optical fiber grating 32, the optical fiber grating 32 is installed on the fixed anchor rod to obtain the optical fiber anchor cable 50, the distributed optical fiber 31 is arranged between the optical fiber anchor cable 50 and the fixed anchor rod to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device;

[0093] The distributed optical fiber 31 is used to test the stress of the entire length of the surrounding rock, thereby achieving full coverage of the entire detection area. The fiber grating 32 is used to perform high-precision stress testing at 1 to 2 meters near the anchor cable. The distributed optical fiber 31 and the fiber grating 32 work together as the optical fiber sensor 30, which can detect tiny deformations and strains and simultaneously test multiple parameters such as temperature, strain, and stress, providing comprehensive test information.

[0094] Step S3: Connect the optical fiber sensor 30 to the test equipment and perform initialization and parameter setting to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device;

[0095] Among them, correct connection is required to ensure the normal operation of the test equipment, parameters such as sampling rate and test range are set according to actual conditions to complete the initialization of the test equipment to ensure the accuracy of the test equipment, and appropriate test parameters are set to improve the accuracy and effectiveness of the test;

[0096] Step S4: using a surrounding rock transparent stress field optical fiber anchor cable testing device to perform testing and analyze the results;

[0097] The result analysis includes the processing and statistical analysis of the test data and the drawing of test result charts or curves to clearly present the changing trends and laws of the test data, so as to gain a comprehensive understanding of the status of the test area.

[0098] Further, step S1 includes:

[0099] Step S101: pre-drilling a hole in the rock mass by using a drilling machine or blasting;

[0100] Step S102: Send the prefabricated fixed anchor rod into the rock mass through the drilling hole to ensure that the length and depth of the anchor cable meet the design requirements;

[0101] Step S103: applying tension to the end or fixed point of the fixed anchor rod so that the anchor cable is tightly combined with the surrounding rock to increase the stability of the support;

[0102] Among them, after the fixed anchor rod is installed, regular monitoring and adjustment are required to ensure that the tension and fixing state of the anchor cable meet the design requirements and to detect and deal with abnormal situations in time.

[0103] Further, step S2 includes:

[0104] Step S201: manufacturing the optical fiber anchor cable 50. The surrounding rock transparent stress field optical fiber anchor cable testing device further comprises: an anchor cable rod body 11 and a steel pipe 33. The optical fiber anchor cable 50 is obtained by embedding the steel pipe 33 in the anchor cable rod body 11 and inserting the optical fiber grating 32 into the steel pipe 33.

[0105] The steel pipe can protect the fiber grating 32 and improve reliability. The fiber anchor cable 50 can provide support and also test stress and temperature changes in real time.

[0106] Step S202: Install the optical fiber anchor cable 50 in the surrounding rock above the working face. On the basis of the original fixed anchor rod support, use the optical fiber anchor cable 50 with a diameter of 21.8 mm × 8200 mm to replace one original fixed anchor rod, anchor the entire length, and use a matching anchor cable dynamometer;

[0107] The anchor cable dynamometer is used to measure the anchor cable tension changes in real time, and to detect and handle abnormal situations in a timely manner;

[0108] Step S203: Install the optical fiber anchor cable 50 on the surrounding rock on the side where mining is not carried out. On the basis of the original fixed anchor rod support, add a 21.8mm×8200mm optical fiber anchor cable 50 at a distance of 2410mm from the bottom plate, anchor the entire length, and use a matching anchor cable dynamometer;

[0109] Step S204: Install the optical fiber anchor cable 50 on the surrounding rock on the mining side, and increase the height of the anchor cable 50 by 1470 mm from the bottom plate. Optical fiber anchor rods, row spacing 2000mm, used with supporting anchor rod dynamometer;

[0110] Step S205: installing the distributed optical fiber 31 by pre-embedding or drilling and implanting;

[0111] The optical fiber anchor cable 50 is used to accurately test the stress change and to provide reinforcement support for the fixed anchor rod. During installation, the optical fiber is pre-buried or drilled to ensure that the optical fiber is tightly integrated with the surrounding rock, thereby improving the accuracy of the test data.

[0112] Further, step S3 includes:

[0113] Step S301: Connect the output end of the optical fiber sensor to the test equipment to ensure that the connection is correct, firm and stable, and perform signal debugging after the connection is completed;

[0114] Step S302: Start the test equipment, select an appropriate demodulator, and set parameters such as sampling rate and test range according to actual conditions. During the initialization setting, the stability and accuracy of the test equipment must also be ensured to ensure the smooth progress of subsequent testing work;

[0115] Among them, the demodulator is used to interpret the fiber optic sensor signal, the sampling rate refers to the frequency of data acquisition by the test equipment, and the test range refers to the range of parameters that the test equipment can test and record;

[0116] Step S303: adjusting the sampling rate and sensitivity according to the test requirements to complete the setting of the test parameters. According to the specific test object and test purpose, reasonably setting these parameters can improve the accuracy and effectiveness of the test;

[0117] Among them, sensitivity is the response degree of the test equipment to signal changes. Reasonable sampling rate and sensitivity settings can maximize the performance of the test equipment and provide high-quality data.

[0118] Further, step S4 includes:

[0119] Step S401: Start the surrounding rock transparent stress field optical fiber anchor cable testing device and data acquisition program to start testing, collect optical fiber sensor signals to test the changes of optical fiber sensor signals in real time, and record the data;

[0120] The data acquisition program is used to collect data from the surrounding rock transparent stress field fiber anchor cable test device. After the program is started, it will automatically start to read data from the sensor and record it in real time. These data provide a basis for subsequent analysis and processing, helping researchers understand the stress change law and trend of the surrounding rock;

[0121] Step S402: Perform data processing as needed, and perform filtering and denoising operations on the collected data;

[0122] Among them, data processing can significantly improve the quality and accuracy of data, reduce the impact of interference and noise on test results, and thus more accurately reflect the changes in the physical state of the surrounding rock, providing a reliable data basis for subsequent analysis and decision-making;

[0123] Step S403: Analyze and evaluate the environmental parameters according to the test data, obtain the change rules and trends of the environmental parameters through the changes in temperature, pressure and strain, and take measures to deal with them;

[0124] The processed data is analyzed to understand the environmental status of the test area, including the spatial distribution of environmental parameters, change trends, abnormal events, etc. The abnormal events are discovered in time through the analysis results and corresponding measures are taken to ensure the safety and stability of the test area;

[0125] Step S405: Display the test data in an intuitive form of charts or curves to present the changing trends and rules of the test data, and summarize and analyze the test results to generate a test report;

[0126] The display of charts and curves can clearly show the changing trends and rules of test parameters, so as to fully understand the status of the test area. The test report is a summary of the test results, including the analysis results of the test data, the evaluation of the changing trends, and the suggestions and improvement measures for the problems found. This information will provide a reference for decision-making and better manage and maintain the safety and stability of the test area.

[0127] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A surrounding rock transparent stress field optical fiber anchor cable testing device, characterized in that: The device comprises: An anchoring assembly (10), wherein the anchoring assembly (10) is fixed inside the surrounding rock; A sealing component (20), wherein the sealing component (20) is a tubular closed structure, and the sealing component (20) is tightly attached to the outer wall of the anchoring assembly (10); An optical fiber sensor (30), the optical fiber sensor (30) is arranged through the interior of the anchoring assembly (10), and the optical fiber sensor (30) comprises: a distributed optical fiber (31) and an optical fiber grating (32), the distributed optical fiber (31) is spirally wound and circumferentially arranged along the outer wall of the anchoring assembly (10), and is folded and placed into the interior of the anchoring assembly (10) when it reaches the end of the anchoring section (113) of the anchoring assembly (10), and the distributed optical fiber (31) is used to perform stress testing on surrounding rocks; the optical fiber grating (32) is radially arranged inside the anchoring assembly (10); A fixed protection component (40), wherein the fixed protection component (40) is respectively arranged in close contact with the anchoring section (113) and the exposed section (111) of the outer wall of the anchoring assembly (10), and the sealing component (20) is sandwiched between the fixed protection component (40); The sealing component (20) is used to prevent slurry from entering the interior of the anchor assembly (10), and the fixed protection component (40) is used to protect the two ends and the interior of the anchor assembly (10) from being affected by external forces during installation and use.

2. The surrounding rock transparent stress field optical fiber anchor cable testing device according to claim 1, characterized in that: The anchor assembly (10) comprises: An anchor cable rod body (11), the anchor cable rod body (11) is a hollow rod-shaped structure and is cylindrical; A grouting pipe (12), wherein the grouting pipe (12) is arranged along the anchor cable rod body (11) and penetrates a grouting section (112) arranged on the anchor cable rod body (11); The anchor rod body (11) is used to provide main structural support, the grouting pipe (12) is used to inject grout into the surrounding rock, and the grouting section (112) of the anchor rod body (11) is provided with circular grouting holes at equal intervals and in parallel.

3. The surrounding rock transparent stress field optical fiber anchor cable testing device according to claim 2, characterized in that: The sealing component (20) comprises: A grouting stopper (21), the grouting stopper (21) being annular and located at a position where the grouting section (112) of the anchor cable rod body (11) abuts against the tray; A rubber layer (22), the rubber layer (22) being a closed structure, the rubber layer (22) being arranged from one side of the grouting stopper (21) to the end of the anchoring section (113) of the anchor cable rod body (11), the rubber layer (22) being sleeved along the circumference of the anchor cable rod body (11) and being tightly attached to the outside of the grouting pipe (12); The slurry stopper (21) is used to prevent slurry from leaking outside the anchor rod body (11), and the rubber layer (22) is used to provide additional sealing protection to prevent foreign matter from entering the interior of the anchor assembly (10).

4. The surrounding rock transparent stress field optical fiber anchor cable testing device according to claim 3, characterized in that: The optical fiber sensor (30) further comprises: A steel pipe (33), the steel pipe (33) being arranged penetrating inside the anchor cable rod body (11); The distributed optical fiber (31) is spirally wound and arranged in an annular direction along the outer wall of the anchor rod body (11), and when it is wound from a side position of the grouting plug (21) of the grouting section (112) to a position of the anchor section (113) of the anchor rod body (11), it is folded and placed in the steel pipe (33) inside the anchor rod body (11); the optical fiber grating (32) is arranged radially inside the anchor rod body (11) and placed in the steel pipe (33); after the distributed optical fiber (31) and the optical fiber grating (32) are laid through the steel pipe (33), they are tested by connecting a test device; the distributed optical fiber (31) is used to perform stress testing on the entire length of the surrounding rock, and the optical fiber grating (32) is used to perform stress testing on an area within two meters of the anchor assembly (10).

5. The surrounding rock transparent stress field optical fiber anchor cable testing device according to claim 2, characterized in that: The fixed protection component (40) comprises: A lock (41), wherein the lock (41) is fixed to the outer wall of the exposed section (111) of the anchor cable rod body (11); A tray (42), the tray (42) being in the shape of a flat plate and being located between the exposed section (111) and the grouting section (112) of the anchor rod body (11) and close to the lock (41); A guide cap (43), the guide cap (43) being located at the end of the anchoring section (113) of the anchor cable rod body (11) and being tapered; A metal guide (44), the metal guide (44) being arranged outside the anchoring section (113) of the anchor rod body (11) and being used to protect the ends of the distributed optical fiber (31) and the optical fiber grating (32); The lock (41) is used to ensure that the anchor assembly (10) is fixed and stable at the installation position to prevent it from being displaced or loosened during use; the tray (42) is used to increase the fixing area of ​​the anchor rod body (11) to disperse the stress on the anchor cable; the guide cap (43) is used to guide the anchor rod body (11) into the surrounding rock to reduce the resistance during installation; and the metal guide head (44) is used to ensure that the end of the optical fiber sensor (30) is not damaged during installation and use.

6. A method for testing surrounding rock transparent stress field optical fiber anchor cable, characterized in that: The method is applied to the device according to any one of claims 1 to 5, comprising the following steps: Step S1: installing prefabricated fixed anchor rods in the surrounding rock using an anchor cable support technology; Step S2: obtaining a surrounding rock transparent stress field optical fiber anchor cable test device, the surrounding rock transparent stress field optical fiber anchor cable test device comprising: an optical fiber sensor (30), the optical fiber sensor (30) comprising: a distributed optical fiber (31), an optical fiber grating (32), the surrounding rock transparent stress field optical fiber anchor cable test device is arranged between the installed fixed anchor rods, the surrounding rock transparent stress field optical fiber anchor cable (50) test device is installed with the optical fiber sensor (30), the optical fiber grating (32) is installed on the fixed anchor rod to obtain the optical fiber anchor cable (50), and the distributed optical fiber (31) is arranged between the optical fiber anchor cable (50) and the fixed anchor rod to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device; Step S3: connecting the optical fiber sensor (30) on the surrounding rock transparent stress field optical fiber anchor cable testing device to the testing equipment and performing initialization and parameter setting; Step S4: Use the surrounding rock transparent stress field optical fiber anchor cable testing device to perform testing and analyze the results.

7. The method for testing surrounding rock transparent stress field optical fiber anchor cable according to claim 6, characterized in that: The step S1 comprises: Step S101: pre-drilling a hole in the rock mass by using a drilling machine or blasting; Step S102: sending the fixed anchor rod into the rock mass through the drill hole; Step S103: applying tension to the end or fixed point of the fixing anchor rod to strengthen the fixing of the fixing anchor rod.

8. The method for testing surrounding rock transparent stress field optical fiber anchor cable according to claim 6, characterized in that: The step S2 comprises: Step S201: manufacturing an optical fiber anchor cable (50), wherein the surrounding rock transparent stress field optical fiber anchor cable testing device further comprises: an anchor cable rod body (11) and a steel pipe (33), wherein the optical fiber anchor cable 50 is obtained by embedding the steel pipe (33) in the anchor cable rod body (11) and inserting the optical fiber grating (32) into the steel pipe (33); Step S201: using the optical fiber anchor cable 50 to replace the original fixed anchor cable in the middle of the top plate of the working face, where the top plate of the working face is the surrounding rock above the working face; Step S202: installing the optical fiber anchor cable 50 on the non-mining side of the working face, wherein the non-mining side of the working face is the surrounding rock on one side that has not been mined; Step S203: installing the optical fiber anchor cable 50 on the mining side of the working face, wherein the mining side of the working face is the surrounding rock on one side of the mining; Step S204: installing the distributed optical fiber (31) by pre-embedding or drilling and implanting.

9. The method for testing surrounding rock transparent stress field optical fiber anchor cable according to claim 6, characterized in that: The step S3 comprises: Step S301: connecting the output end of the optical fiber sensor (30) to a test device and performing signal debugging; Step S302: Start the test equipment, set the sampling rate and test range for initialization; Step S303: adjusting the sampling rate and sensitivity according to the test requirements to complete the setting of the test parameters, so as to complete the installation of the surrounding rock transparent stress field optical fiber anchor cable test device.

10. The method for testing surrounding rock transparent stress field optical fiber anchor cable according to claim 6, characterized in that: The step S4 comprises: Step S401: Start the surrounding rock transparent stress field optical fiber anchor cable testing device and data acquisition program to start testing, monitor the changes of optical fiber sensor signals in real time, and record the data; Step S402: filtering and denoising the collected data; Step S403: Analyze and evaluate the environmental parameters according to the test data, obtain the change rules and trends of the environmental parameters through the changes in temperature, pressure and strain, and take measures to deal with them; Step S405: Display the test data in an intuitive form of charts or curves to present the changing trends and rules of the test parameters, and summarize and analyze the test results to generate a test report.

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