Geocell optical fiber grating sensor packaging method, measurement method and structure

Abstract

The application relates to the technical field of fiber grating packaging, in particular to a geocell fiber grating sensor packaging method, a measuring method and a structure. The geocell fiber grating sensor packaging method of the application realizes stable use of the fiber grating sensor in the geocell by adopting a low-modulus packaging mode of adhesive pasting and pad covering, meanwhile, the fiber gratings arranged in different directions are used to intuitively monitor the deformation amounts of the geocell in different directions, the operation state of the geocell in actual use engineering is comprehensively obtained, the accuracy and convenience of the operation state monitoring of the geocell are improved, and the problems of high cost, low efficiency and long time consumption of the geocell strain monitoring are overcome. The geocell fiber grating sensor measuring method of the application sets the packaging structure including the mutually matched fiber gratings in multiple different directions, the packaging structure is simple, the measuring method is intuitive and accurate, and the operation state of the geocell can be intuitively and accurately obtained.

Description

Technical Field

[0001] This invention relates to the field of fiber optic grating packaging technology, and particularly to a fiber optic grating sensor packaging method, measurement method, and structure for geocells. Background Technology

[0002] Geocells are a common three-dimensional mesh structure in civil engineering, primarily used to prevent soil erosion and maintain soil stability. They are widely applied in slopes, roads, and other areas to form a surface protective layer with good permeability and water retention. Typically made of polymer materials, geocells are mesh structures. Monitoring the stress and deformation of geocell structures in actual engineering projects is crucial for ensuring the long-term stability of engineering structures. Current geocell strain monitoring mainly relies on model tests, indoor experiments, or the installation of flexible displacement gauges, settlement meters, and earth pressure cells around the treated area to indirectly obtain the treatment effect through observation and monitoring data. This approach cannot directly obtain the strain results of the geocells, leading to problems such as high cost, low efficiency, and long processing time in geocell strain monitoring.

[0003] Fiber Bragg grating sensors have been widely used in bridges, tunnels and other fields due to their advantages such as strong resistance to electromagnetic interference, high accuracy, good long-term stability and low price. Unlike wavelength modulation sensors, fiber Bragg grating sensors use the relationship between the reflected wavelength of the fiber grating in the fiber and external physical quantities (such as temperature, stress, etc.) for measurement. The changing reflected wavelength is directly related to the measured physical quantity, and has more intuitive monitoring results.

[0004] However, existing fiber Bragg grating sensors generally use high-modulus packaging methods such as metal and glass fiber, which cannot adapt to the low-modulus, flexible three-dimensional characteristics of geocells. Furthermore, in harsh environments such as vibration and humidity in geocells, existing fiber Bragg grating sensors cannot be directly used stably in geocells.

[0005] Therefore, how to achieve stable and accurate use of fiber Bragg grating sensors in geocells has become an urgent technical problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing fiber Bragg grating sensors in geocells, which cannot be used stably and accurately, and to provide a fiber Bragg grating sensor packaging method, measurement method and structure for geocells.

[0007] In a first aspect, the present invention provides a method for packaging a fiber Bragg grating sensor for a geocell, comprising the following steps: S1. A first fiber grating and a second fiber grating are attached and encapsulated on the wall surface of any one side wall of the geocell using adhesive. A third fiber grating is attached and encapsulated on the other side wall of the same side wall. The encapsulation section of the first fiber grating is arranged horizontally, the encapsulation section of the second fiber grating is arranged vertically, and the third fiber grating is arranged opposite to the second fiber grating to form an encapsulation structure. S2. The optical fiber extending out of the encapsulation structure is protected by a sleeve, and the optical fiber extends to the outdoor connection of the demodulator to the geocell. S3. A pad is used to cover the encapsulation structure. Filler is filled in the geocell chamber to abut the pad against the side wall. The compression modulus of the pad is less than that of the side wall.

[0008] The fiber optic grating sensor packaging method for geocells of the present invention achieves stable use of fiber optic grating sensors in geocells by using a low-modulus packaging method of adhesive bonding and pad covering. At the same time, by setting fiber optic gratings along different directions, it enables intuitive monitoring of the deformation of geocells in different directions, and comprehensively obtains the operating status of geocells in actual engineering applications, improving the accuracy and convenience of geocell operating status monitoring, and overcoming the problems of high cost, low efficiency and long time consumption in geocell strain monitoring.

[0009] Preferably, the sidewall is polished before the bonding and encapsulation area is bonded; the bonding and encapsulation includes applying adhesive to the bonding and encapsulation area to cover the encapsulation segment; the length of the encapsulation segment does not exceed 1 / 5 to 1 / 3 of the sidewall dimension in the corresponding direction.

[0010] Preferably, the pad includes a silicone plate, the thickness of the pad is not less than 1 cm, and the pad covers the adhesive sealing area.

[0011] Preferably, the sleeve is laid along the bottom of the geocell and extends to the outside of the geocell. A protective element is provided at the location where the sleeve passes through the side wall of the geocell. The sleeve is fixedly connected to the side wall within the coverage area of ​​the pad.

[0012] In a second aspect, the present invention provides a method for measuring geocells using fiber optic grating sensors, comprising: Step 1: Form an encapsulation structure on the geocell using the encapsulation method described above; Step 2: Perform strain monitoring of the geocell based on the encapsulation structure. The strain monitoring includes transverse strain monitoring based on the first fiber optic grating and vertical strain monitoring based on the second and third fiber optic gratings.

[0013] The fiber optic grating sensor measurement method for geocells of the present invention uses an encapsulation structure comprising multiple fiber optic gratings in different directions that cooperate with each other. The encapsulation structure is simple, and the measurement method is intuitive and accurate, enabling the intuitive and accurate acquisition of the operating status of the geocell.

[0014] Preferably, the strain monitoring includes obtaining the strain in the corresponding direction by monitoring the wavelength change of the fiber optic grating, wherein the wavelength change of the fiber optic grating... satisfy: ; In the formula: The strain coefficient; As the dependent variable; Temperature coefficient; This represents the change in temperature.

[0015] Preferably, the temperature change is obtained by monitoring the temperature data related to the geocell, and the temperature data is obtained through a temperature-measuring optical fiber installed inside the geocell.

[0016] Preferably, the additional stress of geocells satisfy: ; In the formula: Additional stress in the geocell; The secant modulus of the geocell; This is the diagonal length of the geocell after deformation; This represents the vertical deformation of the geocell. This represents the deformation of the geocell in the lateral direction.

[0017] Preferably, if the geocell is square after being filled with filler material, the deformation of the geocell in the lateral direction is... The deformation obtained from the transverse strain monitoring is multiplied by If the geocell is filled with a regular hexagonal material, the deformation of the geocell in the lateral direction is... The deformation obtained from the transverse strain monitoring is twice that of the original strain. Deformation of geocells in the vertical direction satisfy: ; In the formula: To obtain strain based on a second fiber grating; To obtain strain based on a third fiber grating; The bending strain is obtained based on the second fiber grating and the third fiber grating; This represents the initial height of the sidewall.

[0018] In a third aspect, the present invention provides a fiber optic grating sensor structure for geocells, including an encapsulation structure formed on the geocell according to the encapsulation method described above, and capable of strain monitoring of the geocell using the measurement method described above.

[0019] The fiber Bragg grating sensor structure for geocells of the present invention has a simple packaging structure and an intuitive measurement method, which enables the quick and stable use of fiber Bragg grating sensors in geocells and achieves accurate monitoring of the geocell's operating status.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a method for packaging fiber Bragg grating sensors in geocells. By using a low-modulus packaging method with adhesive bonding and pad covering, the fiber Bragg grating sensor can be used stably in geocells. 2. This invention provides a fiber optic grating sensor packaging method for geocells. By using fiber optic gratings arranged along different directions, it is possible to intuitively monitor the deformation of geocells in different directions, comprehensively obtain the operating status of geocells in actual engineering applications, improve the accuracy and convenience of geocell operating status monitoring, and overcome the problems of high cost, low efficiency and long time consumption in geocell strain monitoring. 3. The present invention provides a fiber optic grating sensor measurement method for geocells. By setting up an encapsulation structure that includes multiple fiber optic gratings in different directions cooperating with each other, the encapsulation structure is simple, the measurement method is intuitive and accurate, and the operating status of the geocell can be obtained intuitively and accurately. 4. This invention provides a fiber optic grating sensor structure for geocells. The packaging structure is simple and the measurement method is intuitive. It enables the quick and stable use of fiber optic grating sensors in geocells and achieves accurate monitoring of the geocell's operating status. Attached Figure Description

[0021] Figure 1 This is a schematic flowchart of the fiber optic grating sensor packaging method for geocells in Example 1. Figure 2 This is a schematic diagram of the packaging structure described in Example 1; Figure 3 for Figure 2 A magnified view of a portion of point A in the diagram; Figure 4 This is a front view of the packaging structure described in this invention; Figure 5 The fiber optic grating sensor measurement method for geocells in Example 2 is used to obtain relevant data graphs of the usage status of a geocell. Marked in the image: 1-First fiber grating, 2-Second fiber grating, 3-Third fiber grating, 4-Backing plate, 5-Sleeve, 6-Adhesive encapsulation area, 7-Geocell, 71-Side wall, 72-Filling material. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0023] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0024] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0025] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0026] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0027] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0028] Example 1 like Figures 1-4 As shown, the fiber optic grating sensor packaging method for geocells in this embodiment includes the following steps: S1. A first fiber grating 1 and a second fiber grating 2 are attached and encapsulated on the wall surface of any one side wall 71 of the geocell 7 using adhesive. A third fiber grating 3 is attached and encapsulated on the other side wall 71. The encapsulation section of the first fiber grating 1 is arranged horizontally, the encapsulation section of the second fiber grating 2 is arranged vertically, and the third fiber grating 3 is arranged opposite to the second fiber grating 2 to form an encapsulation structure. S2. The optical fiber extending out of the encapsulation structure is protected by the sleeve 5, and the optical fiber extends to the outside of the geocell 7 and is connected to the demodulator. S3. The encapsulation structure is covered by a pad 4. The pad 4 is abutted against the side wall 71 by filling the geocell 7 with filler 72. The compression modulus of the pad 4 is less than that of the side wall 71.

[0029] In one or more embodiments, the sidewall 71 is polished to cover the bonding and encapsulation area 6 before bonding and encapsulation; the bonding and encapsulation includes applying adhesive to the bonding and encapsulation area 6 to cover the encapsulation segment.

[0030] Specifically, alcohol can be used to clean the sidewall 71 of the geocell 7, and then sandpaper can be used to polish the bonding and encapsulation area 6 of the sidewall 71. After determining the length of the fiber grating encapsulation section, the fiber grating encapsulation section is attached to the cleaned and polished sidewall 71, and then adhesive is applied to cover the encapsulation section. After the adhesive cures, the fiber grating is bonded and encapsulated on the sidewall 71 of the geocell 7. Polishing ensures a tighter fit between the fiber grating and the sidewall 71 and ensures that the adhesive fully exerts its bonding effect.

[0031] In an optional implementation, the fiber Bragg grating can be temporarily positioned using removable adhesive tape, which is then removed after the adhesive has cured, to ensure that the fiber Bragg grating is tightly fitted to the side wall 71 of the geocell 7.

[0032] In an optional embodiment, the adhesive can be a resin adhesive. The resin adhesive has good adhesion to the side wall 71 of the geocell 7, so as to achieve stable installation of the fiber optic grating on the geocell 7.

[0033] In one or more embodiments, the length of the encapsulation segment does not exceed 1 / 5 to 1 / 3 of the dimension of the sidewall 71 in the corresponding direction. The length of the encapsulation segment is related to the range of the adhesive encapsulation area 6, which needs to completely cover the encapsulation segment. By limiting the range of the adhesive encapsulation area 6, the reinforcement effect of excessive adhesive on the local area of ​​the geocell 7 can be effectively avoided.

[0034] In one or more embodiments, the pad 4 includes a silicone sheet, the thickness of the pad 4 is not less than 1 cm, and the pad 4 covers the adhesive encapsulation area 6. The pad 4 can provide better protection for the fiber Bragg grating bonded to the side wall 71 of the geocell 7, thereby improving the service life and monitoring accuracy of the fiber Bragg grating in the humid and vibrating environment of the geocell 7.

[0035] In an optional embodiment, the pad 4 can be a silicone plate, with a shape similar to the side wall 71 of the geocell 7, and can be rectangular. It can protect the bonding and encapsulation area 6. The pad 4 is not directly bonded to the geocell 7, and the silicone plate has a small compression modulus. The pad 4 is restricted from moving by the gravel or other fillers filling the geocell 7, so it will not affect the strain of the fiber grating, nor will it affect the deformation of the side wall 71 of the geocell 7.

[0036] In one or more embodiments, the sleeve 5 is laid along the bottom of the geocell 7 and extends to the outside of the geocell 7. A protective element is provided at the position where the sleeve 5 passes through the side wall 71 of the geocell 7. The sleeve 5 is fixedly connected to the side wall 71 within the coverage area of ​​the pad 4.

[0037] In an optional embodiment, the sleeve 5 can be installed before the fiber Bragg grating is bonded and encapsulated to protect the optical fiber extending out of the encapsulation structure. It is embedded at the bottom of the geocell 7 and extends outside the geocell 7. A silicone gasket is fitted over the sleeve 5 at the point where it passes through the side wall 71 of the geocell 7. The sleeve 5 provides stable protection for the optical fiber. Furthermore, by fixing the side of the sleeve 5 closest to the bonding and encapsulation area 6 to the geocell 7, it prevents the optical fiber from being pulled apart when the geocell 7 is filled with filler 72. Additionally, the silicone gasket prevents the geocell 7 from causing cutting damage to the sleeve 5.

[0038] The fiber optic grating sensor packaging method for geocells in this embodiment achieves stable use of the fiber optic grating sensor in geocells 7 through a low-modulus packaging method using adhesive bonding and a pad 4. This overcomes the limitations of traditional high-modulus packaging such as metal and glass fiber, which cannot be applied to geocells 7. It enables the application of fiber optic grating sensors in geocells 7. Furthermore, by setting fiber optic gratings along different directions, it allows for intuitive monitoring of strain in different directions of the geocell 7, comprehensively obtaining the operating status of the geocell 7 in actual engineering applications. This ensures accurate acquisition of deformation and additional stress during the use of the geocell 7. The resulting packaging structure is small in size, minimizing its impact on the geocell 7, thus improving the accuracy and convenience of monitoring the operating status of the geocell 7. It also overcomes the problems of high cost, low efficiency, and long time consumption in strain monitoring of geocells 7.

[0039] It should be noted that the fiber optic grating sensor packaging method of the geocell in this embodiment involves setting a second fiber optic grating 2 and a third fiber optic grating 3 opposite to each other on both sides of the sidewall 71 of the geocell 7. The second fiber optic grating 2 and the third fiber optic grating 3 are set vertically. Since the sidewall 71 of the geocell 7 is itself soft and easily deformed and the filling material 72 on both sides cannot be filled completely evenly, the sidewall 71 will inevitably be bent under pressure. Therefore, this embodiment can more accurately obtain the longitudinal deformation of the sidewall 71 of the geocell 7, which has the possibility of soft bending, in actual engineering by setting the second fiber optic grating 2 and the third fiber optic grating 3 opposite to each other. This is the first time that fiber optic grating technology has been used to measure the pressure of geosynthetic materials.

[0040] Example 2 The fiber optic grating sensor measurement method for geocells in this embodiment includes: Step 1, forming an encapsulation structure on geocell 7 using the fiber optic grating sensor encapsulation method of embodiment 1; Step 2, performing strain monitoring of geocell 7 based on the encapsulation structure, wherein the strain monitoring includes transverse strain monitoring based on the first fiber optic grating 1 and vertical strain monitoring based on the second fiber optic grating 2 and the third fiber optic grating 3.

[0041] In one or more embodiments, the strain monitoring includes obtaining strain in a corresponding direction by monitoring the wavelength change of the fiber optic grating, wherein the wavelength change of the fiber optic grating... satisfy: ; In the formula: The strain coefficient; As the dependent variable; Temperature coefficient; This represents the change in temperature.

[0042] Specifically, strain coefficient The typical value obtained from laboratory data can be chosen as 1.0 pm / με; temperature coefficient The values ​​are typically obtained from laboratory data and can be selected as 0.01–0.02 nm / °C.

[0043] In an optional implementation, the temperature change can be obtained by monitoring temperature data related to the geocell 7, which is obtained through a temperature-sensing optical fiber installed inside the geocell 7. The temperature-sensing optical fiber can be installed inside or near the geocell 7, and the ambient temperature change around the geocell 7 can be obtained through the optical fiber. This ensures that the change in fiber optic grating wavelength obtained from strain monitoring is only related to the deformation of the geocell 7, making the monitoring results more intuitive.

[0044] In one or more embodiments, the additional stress of the geocell 7 satisfy: ; In the formula: Additional stress for geocell 7; The secant modulus of geocell 7; This is the length of the diagonal of geocell 7 after deformation; The deformation of geocell 7 in the vertical direction; The deformation of geocell 7 in the lateral direction.

[0045] In an optional embodiment, if the geocell 7 is square after being filled with filler 72, the deformation of the geocell 7 in the lateral direction is... The deformation obtained by transverse strain monitoring (i.e., the deformation measured by the first fiber optic grating 1 set transversely) is satisfied. Multiply by the transverse geometric dimensions of the sidewall 71 of geocell 7) .

[0046] In an optional embodiment, if the geocell 7 is filled with filler material 72 and forms a regular hexagon, the deformation of the geocell 7 in the lateral direction is... The deformation obtained from the transverse strain monitoring is twice that of the original strain.

[0047] In an optional implementation, the deformation of the geocell 7 in the vertical direction satisfy: ; In the formula: To obtain strain based on the second fiber grating 2; To obtain strain based on the third fiber grating 3; The bending strain is obtained based on the second fiber grating 2 and the third fiber grating 3; This is the initial height of sidewall 71.

[0048] Specifically, the deformation of the geocell 7 in the vertical direction The acquisition mechanism is as follows: assuming that the sidewall 71 of the geocell 7 is a thin sheet and the second fiber grating 2 and the third fiber grating 3 are symmetrically bent with corresponding linear bending strains, the strain of the sidewall 71 is obtained based on the second fiber grating 3. The strain of the sidewall 71 was obtained based on the third fiber grating 4. The strain difference between the two sides of the sidewall 71 can represent the bending effect, and thus the bending strain can be determined. The actual compressive strain is the sum of the bending strain and the actual compressive strain. The latter part, that is Therefore, based on the strain per unit length of the sidewall 71 of the geocell 7 that can be obtained from the second fiber grating 2 and the third fiber grating 3, the deformation of the geocell 7 in the vertical direction can be calculated based on the initial height of the sidewall 71. .

[0049] like Figure 5 As shown, the fiber optic grating sensor measurement method for geocells in this embodiment uses an encapsulation structure that includes multiple fiber optic gratings in different directions working together. The encapsulation structure is simple, and the measurement method is intuitive and accurate, enabling the intuitive and accurate acquisition of the operating status of geocell 7.

[0050] Example 3 The fiber optic grating sensor structure for geocells in this embodiment includes an encapsulation structure formed on geocell 7 according to the fiber optic grating sensor encapsulation method for geocells in Embodiment 1, and can perform strain monitoring of geocell 7 using the fiber optic grating sensor measurement method for geocells in Embodiment 2.

[0051] The fiber optic grating sensor structure of the geocell in this embodiment has a simple packaging structure and an intuitive measurement method, which enables the quick and stable use of the fiber optic grating sensor on the geocell 7 and achieves accurate monitoring of the operating status of the geocell 7.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for packaging fiber optic grating sensors for geocells, characterized in that, Includes the following steps: S1. A first fiber grating (1) and a second fiber grating (2) are bonded and encapsulated on the wall surface of any one side wall (71) of the geocell (7) using adhesive. A third fiber grating (3) is bonded and encapsulated on the other side wall (71). The encapsulation section of the first fiber grating (1) is arranged horizontally, the encapsulation section of the second fiber grating (2) is arranged vertically, and the third fiber grating (3) is arranged opposite to the second fiber grating (2) to form an encapsulation structure. The bonding and encapsulation includes applying adhesive to the bonding and encapsulation area (6) to cover the encapsulation section. The length of the encapsulation section does not exceed 1 / 5 to 1 / 3 of the dimension of the side wall (71) in the corresponding direction. S2. The optical fiber extending out of the encapsulation structure is protected by a sleeve (5), and the optical fiber extends to the outside of the geocell (7) and is connected to a demodulator. S3. The encapsulation structure is covered by a pad (4). The pad (4) is abutted against the side wall (71) by filling the geocell (7) with filler (72). The compression modulus of the pad (4) is less than that of the side wall (71). The thickness of the pad (4) is not less than 1 cm. The pad (4) covers the adhesive sealing area (6). The sleeve (5) is laid along the bottom of the geocell (7) and extends to the outside of the geocell (7). A protective part is set at the position where the sleeve (5) passes through the side wall (71) of the geocell (7). The sleeve (5) is fixedly connected to the side wall (71) within the coverage area of ​​the pad (4).

2. The fiber optic grating sensor packaging method for geocells according to claim 1, characterized in that, The sidewall (71) is polished before the adhesive packaging area (6) is applied.

3. The fiber optic grating sensor packaging method for geocells according to claim 2, characterized in that, The pad (4) includes a silicone plate.

4. A method for measuring geocells using fiber optic grating sensors, characterized in that, include: Step 1: Form an encapsulation structure on the geocell (7) using the encapsulation method of any one of claims 1-3; Step 2: Strain monitoring of the geocell (7) based on the encapsulation structure, the strain monitoring includes transverse strain monitoring based on the first fiber grating (1) and vertical strain monitoring based on the second fiber grating (2) and the third fiber grating (3); Based on the strain per unit length of the sidewall (71) of the geocell (7) obtained from the second fiber grating (2) and the third fiber grating (3), the deformation of the geocell (7) in the vertical direction is calculated based on the initial height of the sidewall (71).

5. The fiber optic grating sensor measurement method for geocells according to claim 4, characterized in that, The strain monitoring includes obtaining the strain in the corresponding direction by monitoring the change in the wavelength of the fiber optic grating, wherein the change in the wavelength of the fiber optic grating... satisfy: ; In the formula: The strain coefficient; As the dependent variable; Temperature coefficient; This represents the change in temperature.

6. The fiber optic grating sensor measurement method for geocells according to claim 5, characterized in that, The temperature change is obtained by monitoring the temperature data of the geocell (7), which is obtained by a temperature-measuring optical fiber installed in the geocell (7).

7. The fiber optic grating sensor measurement method for geocells according to claim 5, characterized in that, Additional stress of geocell (7) satisfy: ； In the formula: Additional stress for the geocell (7); The secant modulus of the geocell (7); The length of the diagonal of the deformed geocell (7); The deformation of the geocell (7) in the vertical direction; The deformation of the geocell (7) in the lateral direction.

8. The fiber optic grating sensor measurement method for geocells according to claim 7, characterized in that, If the geocell (7) is square after being filled with filler (72), the deformation of the geocell (7) in the lateral direction is... The deformation obtained from the transverse strain monitoring is multiplied by If the geocell (7) is filled with filler material (72) and forms a regular hexagon, the deformation of the geocell (7) in the lateral direction is... The deformation obtained from the transverse strain monitoring is twice that of the original strain. Deformation of geocell (7) in the vertical direction satisfy: ； In the formula: To obtain strain based on the second fiber grating (2); To obtain strain based on the third fiber grating (3); The bending strain is obtained based on the second fiber grating (2) and the third fiber grating (3); The initial height of the sidewall (71).

9. A fiber optic grating sensor structure for geocells, characterized in that, The encapsulation structure formed on the geocell (7) by the encapsulation method according to any one of claims 1-3 is capable of strain monitoring of the geocell (7) using the measurement method according to any one of claims 4-8.

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