Geotechnical body deformation monitoring device based on fiber grating and brillouin reflection combination

Abstract

The present application belongs to the technical field of geological engineering monitoring, and discloses a rock-soil mass deformation monitoring device based on the combination of fiber grating and Brillouin reflection, which comprises a inclinometer tube, a grating demodulator, a Brillouin optical time domain reflectometer and a data processing unit, the outer surface of the inclinometer tube is provided with a plurality of first armored grating strings and a plurality of second armored grating strings; one end of the first armored grating string and the second armored grating string is connected with the grating demodulator, the outer surface of the inclinometer tube is further fixed with an armored optical cable arranged along the length direction, one end of the armored optical cable is connected with the Brillouin optical time domain reflectometer; the output end of the grating demodulator and the Brillouin optical time domain reflectometer is connected with the data processing unit, the data processing unit is used for fusing the original grating strain data of the grating demodulator and the measurement data of the Brillouin optical time domain reflectometer, and obtaining the rock-soil mass deformation data by demodulation. The present application can better monitor the internal deformation and displacement of the slope, and improve the judgment ability of the deformation trend of the slope.

Description

Technical Field

[0001] This invention belongs to the field of geological engineering monitoring technology, specifically relating to a rock and soil deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection, which is particularly suitable for engineering scenarios such as slopes and foundation pits that require high-precision, long-distance monitoring. Background Technology

[0002] Currently, soil and rock deformation monitoring is a crucial aspect of engineering monitoring technology. This can be achieved by using inclinometers. Existing inclinometers often employ independent sensing methods, such as traditional resistance strain gauges or single-grating inclinometers, which suffer from insufficient monitoring accuracy, susceptibility to interference, and poor data consistency over long distances. For instance, traditional resistance strain gauges are susceptible to temperature fluctuations, leading to significant error accumulation in long-distance monitoring (up to 100m). Single-grating inclinometers can only collect data from one side, making it difficult to comprehensively reflect the bending deformation of the tube, and the large distance between adjacent monitoring points (often greater than 1m) causes subtle local deformations to be missed.

[0003] Furthermore, existing technologies lack a systematic design for grating deployment, resulting in arbitrary wavelength selection, signal crosstalk, and increased demodulation difficulty. Additionally, long-distance inclinometer tubes are mostly monolithic structures, making transportation and installation inconvenient, while segmented structures often suffer from inadequate connection handling, affecting monitoring continuity and failing to accurately identify the direction of tilt.

[0004] In summary, existing soil and rock deformation monitoring devices are insufficient to meet engineering requirements for long-distance, high-precision deformation monitoring. Summary of the Invention

[0005] To address the technical challenge of ensuring data accuracy and consistency in long-distance monitoring using existing soil and rock deformation monitoring devices, this invention proposes a soil and rock deformation monitoring device based on a combination of fiber optic gratings and Brillouin reflection. This device aims to improve the accuracy of slope deformation trend assessment and provide more comprehensive spatial information support for disaster early warning.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a soil and rock deformation monitoring device based on the combination of fiber optic gratings and Brillouin reflection, comprising: a clinometer, a grating demodulator, a Brillouin optical time domain reflectometer, and a data processing unit. A first armored grating string and a second armored grating string are fixedly arranged on both sides of the outer surface of the clinometer, with opposite positions. Both the first and second armored grating strings are formed by multiple sub-grating strings continuously arranged along the length of the clinometer. Each sub-grating string includes several FBG gratings with different center wavelengths, and the positions of the FBG gratings on the first and second armored grating strings correspond one-to-one on the clinometer. One end of each sub-grating string is connected to the grating demodulator. An armored optical cable extending along the length of the clinometer is also provided on the outer surface of the clinometer, and one end of the armored optical cable is connected to the Brillouin optical time domain reflectometer. The output terminals of the grating demodulator and the Brillouin optical time domain reflectometer are connected to the data processing unit. The data processing unit is used to fuse the original grating strain data from the grating demodulator and the measurement data from the Brillouin optical time domain reflectometer, and demodulate the deformation data of the soil and rock mass based on the fused strain data.

[0007] The measurement data from the Brillouin optical time-domain reflectometer includes temperature data and raw Brillouin strain data; the method by which the data processing unit fuses the raw grating strain data from the grating demodulator and the measurement data from the Brillouin optical time-domain reflectometer is as follows: Step 1: Measure the temperature data along the inclinometer tube using a Brillouin optical time-domain reflectometer; and perform temperature correction on the raw grating strain data obtained from the grating demodulator. The correction formula is as follows: ; in, This represents the temperature-corrected grating strain data. This represents the original grating strain data; Indicates the temperature coefficient of the grating; The initial temperature. Indicates the position measured by the Brillouin optical time domain reflectometer The temperature at that location, where t represents time; Step 2: Calculate the measurement error of the Brillouin optical time domain reflectometer at each corresponding measurement point based on the temperature-corrected grating strain data. The calculation formula is as follows: ; in, This indicates the position of the Brillouin optical time domain reflectometer. Measurement error at the location, This indicates the position of the Brillouin optical time domain reflectometer. The original Brillouin strain data measured at the location; Step 3: Establish an error distribution model for the Brillouin optical time-domain reflectometer's measurement error as a function of position x using polynomial fitting. The polynomial is: ; in , , The fitting coefficients at time t are represented by the least squares method. This represents the measurement error of the Brillouin optical time domain reflectometer at position x; Step 4: Using the fitted error distribution model, correct the original Brillouin strain data of all sampling points along the entire line obtained by the Brillouin optical time-domain reflectometer: ; in, This represents the corrected Brillouin strain data. This represents the original Brillouin strain data; Step 5: Using the corrected Brillouin strain data as the data base and the temperature-corrected grating strain data as the boundary, obtain the fused strain data.

[0008] The data processing unit is also used to calculate the original grating strain data and determine the displacement and tilt direction of the inclinometer tube based on the wavelength drift values ​​corresponding to the first armored grating string and the second armored grating string.

[0009] The demodulation formula for obtaining the soil deformation data from the fused strain data obtained by the data processing unit is as follows: ; in, Let x represent the displacement at position x, t represent time, A represent the demodulation matrix, h represent the spacing between adjacent FBG gratings, and n represent a positive integer less than 10. This represents the temperature-corrected grating strain data. This indicates the position of the i-th FBG grating. This represents the corrected Brillouin strain data.

[0010] The data processing unit is also used to calculate the curvature along the inclinometer tube based on the fused strain data, using the following formula: ; in, This represents the fused strain data, where R represents the radius of the inclinometer tube and k represents the curvature.

[0011] Sixteen FBG gratings are uniformly arranged on the sub-gratings of the first and second armored grating strings, and the center wavelength difference of each FBG grating is 3nm.

[0012] On the first and second armored grating strings, the spacing between adjacent FBG gratings is 0.5-3m.

[0013] The inclinometer tube has a segmented structure, including multiple inclinometer branch tubes, which are seamlessly connected in sequence through connectors to form the inclinometer tube.

[0014] The length of the inclinometer branch pipe is 4m.

[0015] Compared with the prior art, the present invention has the following advantages: This invention proposes a soil and rock deformation monitoring device based on the combination of fiber optic gratings and Brillouin reflection, comprising a grating demodulator and a Brillouin optical time domain reflectometer (BOTDR). It leverages the distributed and continuous monitoring advantages of the BOTDR to overcome the point-based and intermittent monitoring limitations of the grating demodulator. Simultaneously, it uses the high-precision point data from the grating demodulator as anchor points to ensure the measurement accuracy of the BOTDR and prevent overall frequency shift errors in the system's measurement data. The fused data combines the high-speed response characteristics of the BOTDR with the high precision of the grating demodulator. Therefore, this invention can better monitor the internal deformation and displacement of slopes, improve the ability to judge slope deformation trends, and provide more comprehensive spatial information support for disaster early warning. Furthermore, the two armored grating strings can detect the deformation direction. Attached Figure Description

[0016] Figure 1 A schematic diagram of a rock and soil deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the installation of the first armored grating string and the second armored grating string in an embodiment of the present invention; Figure 3 The above are the horizontal displacement curves of the inclinometers installed in the open-pit mine at different times, obtained by a grating demodulator in this embodiment of the invention. Figure 4 This is a schematic diagram of the monitoring device in an embodiment of the present invention installed on a slope.

[0017] In the figure: 1 is the inclinometer tube, 2 is the grating demodulator, 3 is the Brillouin optical time domain reflectometer, 4 is the data processing unit, 5 is the first armored grating string, 6 is the second armored grating string, 7 is the armored optical cable, and 8 is the armored communication optical cable. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figure 1-2 As shown, this embodiment of the invention provides a soil and rock deformation monitoring device based on the combination of fiber optic gratings and Brillouin reflection, including: a clinometer 1, a grating demodulator 2, a Brillouin optical time domain reflectometer 3, and a data processing unit 4; a first armored grating string 5 and a second armored grating string 6 are respectively fixedly arranged on both sides of the outer surface of the clinometer 1, with opposite positions. The first armored grating string 5 and the second armored grating string 6 are each formed by multiple sub-grating strings continuously arranged along the length direction of the clinometer 1; the sub-grating strings include several FBG gratings with different center wavelengths, and the positions of the FBG gratings on the first armored grating string 5 and the second armored grating string 6 on the clinometer 1 correspond one-to-one; one end of each sub-grating string is connected to the grating demodulator 2; an armored optical cable 7 extending along the length direction of the clinometer 1 is also provided on the outer surface of the clinometer 1, and one end of the armored optical cable 7 is connected to the Brillouin optical time domain reflectometer 3.

[0020] In this embodiment, regardless of whether it is the first armored grating string 5 or the second armored grating string 6, the center wavelengths of each FBG grating in the same sub-grating string are different. The positions of the FBG gratings on the first armored grating string 5 and the second armored grating string 6 on the inclinometer tube 1 correspond one-to-one, meaning that the setting depth of each FBG grating on the first armored grating string 5 is the same as the setting depth of each FBG grating on the second armored grating string 6.

[0021] The outputs of the grating demodulator 2 and the Brillouin optical time-domain reflectometer 3 are connected to the data processing unit 4. The data processing unit 4 is used to fuse the raw grating strain data from the grating demodulator 2 and the measurement data from the Brillouin optical time-domain reflectometer 3, and demodulate the deformation data of the soil and rock mass based on the fused strain data. The measurement data from the Brillouin optical time-domain reflectometer 3 includes temperature data and raw Brillouin strain data.

[0022] Specifically, in this embodiment, the method by which the data processing unit 4 fuses the raw grating strain data of the grating demodulator 2 and the measurement data of the Brillouin optical time-domain reflectometer 3 is as follows: Step 1: Measure the temperature data along the inclinometer tube 1 using the Brillouin optical time-domain reflectometer 3; and perform temperature correction on the raw grating strain data obtained from the grating demodulator 2. The correction formula is: ; (1) in, This represents the temperature-corrected grating strain data. This represents the original grating strain data; Indicates the temperature coefficient of the grating; The initial temperature. This indicates the position measured by the Brillouin optical time domain reflectometer 3. The temperature at that location, and t represents time.

[0023] The formula for calculating the original grating strain data obtained by the grating demodulator 2 is as follows: = (2) in, Indicates the wavelength drift and strain calculation coefficients. and These represent the wavelength shift of the FBG grating corresponding to the position in the first armored grating string 5 and the second armored grating string 6, respectively.

[0024] Step 2: Calculate the measurement error of the Brillouin optical time domain reflectometer 3 at each corresponding measurement point based on the temperature-corrected grating strain data. The calculation formula is as follows: (3) in, This indicates that the Brillouin optical time domain reflectometer 3 is in position. Measurement error at the location, This indicates that the Brillouin optical time domain reflectometer 3 is in position. The original Brillouin strain data measured at the location.

[0025] Step 3: Establish an error distribution model for the measurement error of the Brillouin optical time-domain reflectometer 3 as a function of position x using polynomial fitting. The polynomial is: ; (4) in , , for The fitting coefficients at time points are obtained using the least squares method. This represents the measurement error of the Brillouin optical time domain reflectometer 3 at position x.

[0026] Step 4: Using the fitted error distribution model, correct the original Brillouin strain data of all sampling points along the entire armored optical cable 7 obtained by the Brillouin optical time domain reflectometer 3. The correction formula is as follows: ; (5) in, This represents the corrected Brillouin strain data. This represents the raw Brillouin strain data obtained from the Brillouin optical time-domain reflectometer 3.

[0027] Step 5: Using the corrected Brillouin strain data as the data base and the temperature-corrected grating strain data as the boundary, obtain the fused strain data.

[0028] The aforementioned data fusion process achieves "point-to-surface integration, precision complementarity, and data mutual verification" through the synergy of "quasi-distributed grating strain data + fully distributed Brillouin strain data". Specifically, the high-precision point data from the grating demodulator supplements the single-point precision deficiency of the Brillouin optical time domain reflectometer, while the fully distributed data from the Brillouin optical time domain reflectometer fills the gaps in grating monitoring. At the same time, bidirectional calibration ensures data reliability. Finally, using the corrected Brillouin strain data as the data basis and the temperature-corrected grating strain data as the boundary, the fused strain data is obtained, which can provide complete data support for slope deformation monitoring with "precise point location and continuous data along the entire line".

[0029] Specifically, in this embodiment, the data processing unit 4 is further configured to calculate the original grating strain data and determine the displacement and tilt direction of the inclinometer tube 1 based on the wavelength drift values ​​corresponding to the first armored grating string 5 and the second armored grating string 6. The calculation formula for the original grating strain data is the above formula (2).

[0030] When the inclinometer tube 1 bends due to the deformation of the soil and rock, compressive strain will be generated on the inner side (concave side) of the tube and tensile strain will be generated on the outer side (convex side). The wavelength drift values ​​collected by the first armored grating string 5 and the second armored grating string 6 respectively reflect the strain data on both sides of the tube body of the inclinometer tube 1, which can completely reflect the bending deformation characteristics of the tube body, rather than a single-sided grating that can only collect a single strain trend. At the same time, the FBG gratings with a spacing of 1m evenly distributed on both sides of the inclinometer tube 1 can accurately capture the small bending deformation of the tube body, solving the problem that traditional single-sided monitoring is prone to missing minute deformations.

[0031] By comparing the strain differences measured by the first armored grating string 5 and the second armored grating string 6 at the same depth or location, the tilt direction of the inclinometer tube 1 (i.e., the soil and rock mass) can be directly determined: when the strain of the grating string located inside the soil and rock mass increases and the strain of the outer grating string decreases, it indicates that the soil and rock mass tilts towards the inside of the inclinometer tube 1; when the strain of the outer grating string increases and the strain of the inner grating string decreases, it indicates that the soil and rock mass tilts towards the outside of the inclinometer tube 1; if the strain on both sides changes synchronously, it indicates that the inclinometer tube has undergone overall axial deformation (such as settlement). This directional identification capability is not available in existing single-sided grating monitoring devices, providing crucial spatial orientation information for disaster early warning in projects such as slopes and foundation pits, and accurately locating the tilt trend of the deformation area.

[0032] The strain data collected by the first armored grating string 5 and the second armored grating string 6 at the same depth position are physically correlated, and the tension and compression under bending deformation are complementary. This physical law can be used to cross-calibrate the data on both sides, eliminate abnormal data caused by grating aging, installation deviation, and environmental interference, improve the reliability of grating strain data, and provide a more accurate "true value benchmark" for subsequent Brillouin optical time domain reflectometer accuracy compensation.

[0033] In addition, in this embodiment, two grating strings are set up: the first armored grating string 5 and the second armored grating string 6. They are continuously arranged along the length of the inclinometer tube 1. The strain variation trend with depth / length should be consistent with the bending deformation law of the tube body. The synchronicity of the strain trends on both sides can verify the authenticity of the monitoring data. If an abnormal trend appears in the data on one side, it can be quickly judged as a sensor element failure or installation problem, which facilitates the troubleshooting of the equipment on site and ensures the stability of long-term monitoring.

[0034] Furthermore, in this embodiment, the data processing unit 4 is also used to demodulate the deformation data of the soil and rock mass based on the fused strain data obtained by fusion.

[0035] Specifically, in this embodiment, the first armored grating string 5 and the second armored grating string 6 are equipped with 16 FBG gratings uniformly arranged on the sub-grating strings, and the center wavelengths of each FBG grating differ by 3nm.

[0036] Specifically, the center wavelengths of the FBG gratings set on the first armored grating string 5 and the second armored grating string 6 are 1524nm, 1527nm, 1529nm, 1531nm, 1534nm, 1537nm, 1539nm, 1541nm, 1544nm, 1547nm, 1549nm, 1551nm, 1554nm, 1557nm, 1559nm, and 1561nm, respectively. The spacing between adjacent wavelengths is reasonable, which can avoid signal crosstalk between adjacent gratings.

[0037] Specifically, the adjacent FBG gratings on the first armored grating string 5 and the second armored grating string 6 are spaced 0.5-3m apart. In this embodiment, the spacing between adjacent FBG gratings is set to 1m.

[0038] Furthermore, in this embodiment, the inclinometer tube 1 has a segmented structure, including multiple inclinometer branch tubes, and each inclinometer branch tube is seamlessly connected through connectors to form the inclinometer tube 1.

[0039] Furthermore, in this embodiment, the length of the inclinometer branch pipe is 4m. Taking the slope rock and soil deformation monitoring of a certain project as an example, the total length of the inclinometer pipe 1 is 100m, and a total of 25 inclinometer branch pipes are required. Every 4 inclinometer branch pipes share 2 sub-grating strings with a length of 16m, and a minimum of 14 sub-grating strings are required. The corresponding grating demodulator 2 only needs 14 channels to meet the monitoring of rock and soil deformation data for 100m.

[0040] In this embodiment of the invention, after the data processing unit 4 completes the data fusion of the grating demodulator 2 and the Brillouin optical time domain reflectometer 3 to obtain fused strain data, it also needs to convert it into the overall continuous displacement data along the path of the inclinometer 1. The core of the conversion is based on the beam bending deformation theory of mechanics of materials. Combining the structural characteristics of the inclinometer 1 and the grating layout parameters, the conversion is realized through the logic chain of strain-curvature-displacement. The material mechanics conversion logic of strain-curvature-displacement is integrated to form a complete closed-loop conversion method from the original wavelength signal of the grating → fused strain data → overall continuous displacement data.

[0041] Specifically, integrating strain data The unified definition across the entire domain is: ; (6) Where m represents the number of FBG gratings along the path of inclinometer tube 1, n represents a positive integer less than 10, and h represents the spacing between adjacent FBG gratings. This indicates the position of the i-th FBG grating along the path of inclinometer tube 1.

[0042] In this embodiment, the fused strain replaces the original grating strain and is used as the basis for calculating the curvature along the path of the inclinometer tube 1. The calculation formula is as follows: (7) in This represents the curvature of inclinometer tube 1. Indicates the radius of curvature. It is the pure bending moment applied to the inclinometer casing. It is the Young's modulus of the inclinometer casing. I R represents the moment of inertia, and R represents the radius of the inclinometer tube 1.

[0043] The core principle of calculating continuous displacement across the entire domain by fusing strain data is as follows.

[0044] Substituting the fused strain data into the original second-order difference equation, which reflects the intrinsic relationship between fused strain and displacement at adjacent points, we have: (8) in, , , Let represent the horizontal displacements of the (i+1), (i), and (i-1)th FBG gratings, respectively, and h represent the spacing between adjacent FBG gratings; representing this in matrix form, we have: (9) Where A represents the demodulation matrix, and f represents the horizontal displacement vector, which is defined as: (10) The size of the demodulation matrix A is directly determined by the number of grating points; therefore, the displacement data along the inclinometer tube 1 can be calculated by fusing strain data, thus obtaining the global displacement at fixed intervals. The final calculation formula is: (11) in, Let x represent the displacement at position x, t represent time, A represent the demodulation matrix, n represent a positive integer less than 10, and h represent the spacing between adjacent FBG gratings. This represents the temperature-corrected grating strain data. This indicates the position of the i-th FBG grating. This represents the corrected Brillouin strain data. When the spacing between adjacent FBG gratings is 1m, the fixed interval corresponding to the above formula is 0.1m.

[0045] Figure 3 The above are the horizontal displacement curves of the inclinometers installed in the open-pit mine at different times, obtained by a grating demodulator in this embodiment of the invention. Figure 4 This is a schematic diagram of the actual on-site installation of the inclinometer tube 1 in an embodiment of the present invention, as shown below. Figure 4 As shown, the inclinometer tube 1 is installed in the slope of the open-pit mine and is set in a vertical direction, wherein the first armored grating string 5 and the second armored grating string 6 are located on the inner and outer sides of the slope, respectively.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A soil and rock deformation monitoring device based on a combination of fiber optic gratings and Brillouin reflection, characterized in that, include: The inclinometer (1), grating demodulator (2), Brillouin optical time domain reflectometer (3), and data processing unit (4) are provided. On the outer surface of the inclinometer (1), a first armored grating string (5) and a second armored grating string (6) are fixedly arranged on both sides, with opposite positions. The first armored grating string (5) and the second armored grating string (6) are formed by multiple sub-grating strings continuously arranged along the length of the inclinometer (1). The sub-grating string includes several FBG gratings with different center wavelengths, and the positions of the FBG gratings on the first armored grating string (5) and the second armored grating string (6) on the inclinometer (1) correspond one-to-one. One end of each sub-grating string is connected to the grating demodulator (2). The outer surface of the inclinometer (1) is also provided with an armored optical cable (7) extending along the length of the inclinometer (1), and one end of the armored optical cable (7) is connected to the Brillouin optical time domain reflectometer (3). The output terminals of the grating demodulator (2) and the Brillouin optical time-domain reflectometer (3) are connected to the data processing unit (4). The data processing unit (4) is used to fuse the original grating strain data of the grating demodulator (2) and the measurement data of the Brillouin optical time-domain reflectometer (3), and demodulate the deformation data of the soil and rock mass based on the fused strain data. The measurement data of the Brillouin optical time-domain reflectometer (3) includes temperature data and original Brillouin strain data. The method by which the data processing unit (4) fuses the original grating strain data of the grating demodulator (2) and the measurement data of the Brillouin optical time-domain reflectometer (3) is as follows: Step 1: Measure the temperature data along the inclinometer tube (1) using a Brillouin optical time-domain reflectometer (3); and perform temperature correction on the original grating strain data obtained from the grating demodulator (2). The correction formula is as follows: ； in, This represents the temperature-corrected grating strain data. This represents the original grating strain data; Indicates the temperature coefficient of the grating; The initial temperature. This indicates the position measured by the Brillouin optical time domain reflectometer (3). The temperature at that location, where t represents time; Step 2: Calculate the measurement error of the Brillouin optical time domain reflectometer (3) at each corresponding measurement point based on the temperature-corrected grating strain data. The calculation formula is as follows: ； in, This indicates that the Brillouin optical time domain reflectometer (3) is located at... Measurement error at the location, This indicates that the Brillouin optical time domain reflectometer (3) is located at... The original Brillouin strain data measured at the location; Step 3: Establish an error distribution model of the measurement error of the Brillouin optical time-domain reflectometer (3) as a function of position x using polynomial fitting. The polynomial is: ； in , , The fitting coefficients at time t are represented by the least squares method. This represents the measurement error of the Brillouin optical time-domain reflectometer (3) at position x; Step 4: Using the fitted error distribution model, correct the original Brillouin strain data of all sampling points along the entire line obtained by the Brillouin optical time-domain reflectometer (3): ； in, This represents the corrected Brillouin strain data. This represents the original Brillouin strain data; Step 5: Using the corrected Brillouin strain data as the data base and the temperature-corrected grating strain data as the boundary, obtain the fused strain data.

2. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, The data processing unit (4) is also used to calculate the original grating strain data and determine the displacement and tilt direction of the inclinometer tube (1) based on the wavelength drift values ​​corresponding to the first armored grating string (5) and the second armored grating string (6).

3. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, The demodulation formula for the soil deformation data obtained by the data processing unit (4) based on the fused strain data is as follows: ； in, Let x represent the displacement at position x, t represent time, A represent the demodulation matrix, h represent the spacing between adjacent FBG gratings, and n represent a positive integer less than 10. This represents the temperature-corrected grating strain data. This indicates the position of the i-th FBG grating. This represents the corrected Brillouin strain data.

4. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, The data processing unit (4) is also used to calculate the curvature along the path of the inclinometer tube (1) based on the fused strain data. The calculation formula is as follows: ； in, The fused strain data is represented by R, which represents the radius of the inclinometer tube (1), and k represents the curvature.

5. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, The first armored grating string (5) and the second armored grating string (6) are equipped with 16 FBG gratings uniformly arranged on the sub-grating strings, and the center wavelength difference of each FBG grating is 3nm.

6. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, On the first armored grating string (5) and the second armored grating string (6), the spacing between adjacent FBG gratings is 0.5-3m.

7. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 1, characterized in that, The inclinometer tube (1) has a segmented structure, including multiple inclinometer branch tubes, which are seamlessly connected in sequence through connectors to form the inclinometer tube (1).

8. The soil and rock deformation monitoring device based on the combination of fiber optic grating and Brillouin reflection according to claim 7, characterized in that, The length of the inclinometer branch pipe is 4m.

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