Distributed fiber optic sensing temperature compensation device for dynamic response of hydraulic structures under wave impact and its application method

Abstract

This invention discloses a distributed optical fiber sensing temperature compensation device and its application method for the dynamic response of hydraulic structures under wave impact. The device includes a vibration sensing fiber and a temperature compensation fiber. The vibration sensing fiber passes through a temperature compensation unit, and the temperature compensation fiber passes through a dustproof and waterproof module, a guiding component, and a prestress adjustment module within the temperature compensation unit to achieve temperature compensation. Through optical signal demodulation, the vibration sensing fiber measures the vibration signal and temperature change signal of the structure under test, while the temperature compensation fiber measures the temperature change signal at the same location on the structure. The temperature compensation unit performs error calibration on the signal measured by the temperature compensation fiber. Compared with existing technologies, this invention achieves continuous temperature compensation across the entire range of vibration sensing signals in a physical sense, offering significant advantages in improving the accuracy of distributed optical fiber vibration sensing and promoting the application of distributed optical fiber vibration sensing technology in hydraulic engineering.

Description

Technical Field

[0001] This invention relates to the field of fiber optic sensing technology for vibration signals of water structures, specifically to a distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact and its application method. Background Technology

[0002] Structural health monitoring at locations such as high dams, large reservoirs, long-distance water conveyance channels, and estuaries is crucial for ensuring the safe and stable operation of these projects and realizing their economic and social benefits on schedule. However, the complex operating environment of water-related structures often necessitates the deployment of various types of large-scale monitoring instruments to comprehensively cover structural health monitoring needs. In recent years, fiber optic monitoring technology has developed rapidly. Its advantages, including a wide range of monitoring targets, low-cost sensing elements, broad coverage, corrosion resistance, and resistance to electromagnetic interference, have led to its successful demonstration applications in practical engineering. With the continuous development of technologies such as optical signal demodulation, informatization, and intelligentization, distributed fiber optic vibration sensing technology, characterized by high-frequency measurement, is gradually being improved and is expected to be applied in practical engineering projects.

[0003] However, current distributed fiber optic sensing technologies all possess dual sensitivity to stress and temperature. When applied to vibration sensing of hydraulic engineering structures, there is a problem of cross-coupling between stress and temperature sensing signals. Especially under wave loads, the temperature differences between different water depths and between water and air make it difficult to accurately distinguish the actual vibration signals of the structure. Temperature compensation methods in distributed fiber optic sensing technology have proven their necessity in projects such as fiber optic gratings and fiber optic static monitoring. However, there is currently little research on temperature compensation methods for distributed fiber optic vibration sensing technology, which has become a major obstacle to the practical engineering application and promotion of this technology. Summary of the Invention

[0004] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides a distributed optical fiber sensing temperature compensation device and its application method for the dynamic response of hydraulic structures under wave impact. It has outstanding advantages in improving the accuracy of distributed optical fiber vibration sensing and promoting the application of distributed optical fiber vibration sensing technology in water conservancy projects.

[0005] Technical Solution: This invention discloses a distributed optical fiber sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact, including a sensing optical fiber connected to an optical demodulator via a communication optical fiber. The sensing optical fiber includes a vibration sensing section optical fiber and a temperature compensation section optical fiber, which are laid parallel and adjacent to each other on the surface of the hydraulic structure to be tested. It also includes a number of temperature compensation units spaced apart on the surface of the hydraulic structure to be tested. The temperature compensation unit includes a dustproof and waterproof module, a guiding component, and a sensing optical fiber prestress adjustment module.

[0006] The dustproof and water-proof module includes an outer sealing box and an inner sealing box. The outer sealing box is fixed to the surface of the hydraulic structure to be tested, and an inner sealing box is provided inside it. The inner sealing box is a prefabricated sealing component. The outer sealing box and the inner sealing box are connected by a vibration isolation module, and the inner sealing box does not contact the surface of the hydraulic structure to be tested. The inner sealing box is provided with a guide component and a sensing fiber prestress adjustment module. The sensing fiber prestress adjustment module is used to adjust the prestress of the sensing fiber. The guide component is used to guide and pull the temperature compensation section fiber entering the inner sealing box to the reserved outlet position of the outer sealing box.

[0007] The vibration sensing fiber passes directly through the outer sealed box. The left and right temperature compensation fiber sections are connected by a temperature compensation unit. After passing through the outer sealed box, they are guided by a guide component in the inner sealed box and connected to the sensing fiber prestress adjustment module. The prestress of the temperature compensation fiber section in the inner sealed box is adjusted by the sensing fiber prestress adjustment module.

[0008] The vibration sensing fiber is fixed to the surface of the hydraulic structure under test with silicone sealant, and passes directly through the outer sealing box and is sealed with silicone sealant. The temperature compensation fiber on the outside of the temperature compensation unit is inserted into the outer fiber optic sleeve, and a silicon-based lubricating layer is provided between the temperature compensation fiber and the outer fiber optic sleeve. The outer fiber optic sleeve is fixed to the surface of the hydraulic structure with silicone sealant. The temperature compensation fiber on the inside of the temperature compensation unit is cut off from the outer fiber optic sleeve after entering the temperature compensation unit, and extends further into the inner fiber optic sleeve of the temperature compensation unit. At the cut-off point of the temperature compensation fiber optic sleeve, a thin film is used to seal it to prevent the silicon-based lubricating layer from overflowing.

[0009] Furthermore, the vibration isolation module includes lower support platforms on both sides of the outer sealing box, air spring vibration isolators on both sides, and upper connecting platforms on both sides of the inner sealing box. The air spring vibration isolators on both sides are arranged between the lower support platforms and the upper connecting platforms, and the inner sealing box is connected to the outer sealing box through the vibration isolation module.

[0010] Furthermore, the guiding assembly includes a first guide wheel, a second guide wheel, a third guide wheel, and a fourth guide wheel. The first and fourth guide wheels are mounted on the outside of the inner sealed box via brackets, while the second and third guide wheels are mounted on the inside of the inner sealed box via brackets. The first guide wheel guides the temperature compensation fiber optic section entering the outer sealed box obliquely upward from the surface of the hydraulic structure to the second guide wheel. The second guide wheel guides the temperature compensation fiber optic section to the third guide wheel. The third guide wheel guides the temperature compensation fiber optic section downward obliquely to the fourth guide wheel. The fourth guide wheel guides the temperature compensation fiber optic section back to the surface of the hydraulic structure. The second and third guide wheels are horizontally arranged, and the external fiber optic sleeves between the first and second guide wheels and between the third and fourth guide wheels are arranged in an "X" shape.

[0011] Furthermore, the sensing fiber optic prestress adjustment module includes a first fastening post, a second fastening post, a third axial traction post, a fourth fastening post, a fifth longitudinal traction post, a sixth fastening post, a seventh axial traction post, an eighth fastening post, and a ninth fastening post; the external fiber optic sleeve between the first guide wheel and the second guide wheel sequentially passes through the first fastening post, the second fastening post, and the third axial traction post; the external fiber optic sleeve between the third guide wheel and the fourth guide wheel sequentially passes through the seventh axial traction post, the eighth fastening post, and the ninth fastening post; the external fiber optic sleeve between the second and third guide wheels sequentially passes through the fourth fastening post, the fifth longitudinal traction post, and the sixth fastening post.

[0012] The first, second, fourth, sixth, eighth, and ninth fastening posts are equipped with internal fiber optic sleeve clamping assemblies for clamping the internal fiber optic sleeves located within the corresponding fastening posts. The fifth longitudinal traction post is equipped with a clamping sliding assembly for clamping and sliding the internal fiber optic sleeve within the fifth longitudinal traction post. The third and seventh axial traction posts are equipped with clamping oblique sliding assemblies for clamping and obliquely moving the internal fiber optic sleeves within the third and seventh axial traction posts, thereby tightening the fiber optic sleeves and their internal fibers before the third axial traction post and after the seventh axial traction post.

[0013] Furthermore, the internal fiber optic sleeve clamping assembly includes a first threaded post, the upper end of which is connected to a corresponding fastening post via a bearing. The upper and lower ends of the first threaded post are provided with reverse threads, and the reverse thread mating point is located at the point where the internal fiber optic sleeve passes through. Clamping blocks are threadedly connected to the reverse threads at the upper and lower ends respectively. When a pair of clamping blocks clamp the internal fiber optic sleeve, the opposite surfaces of the clamping blocks match the extension direction of the internal fiber optic sleeve.

[0014] Furthermore, the clamping and sliding assembly includes a second threaded post, the upper end of which is connected to a fifth longitudinal traction post via a bearing, and a second slider is threaded onto the second threaded post. The internal optical fiber sleeve passes through the second slider and does not contact the second threaded post.

[0015] Furthermore, the clamping oblique movement assembly includes an electric slide rail or a telescopic cylinder that extends and retracts along the extension direction of the inner optical fiber sleeve, which is disposed inside the third axial traction column and the seventh axial traction column. A finger cylinder is provided on the actuating end of the electric slide rail or the telescopic cylinder, and the actuating end of the finger cylinder is aligned with the inner optical fiber sleeve that passes through the third axial traction column and the seventh axial traction column.

[0016] Furthermore, prestressed springs are respectively provided between the second fastening column and the third axial traction column, and between the seventh axial traction column and the eighth fastening column. One end of the prestressed spring is connected to the column body of the second fastening column or the eighth fastening column, and the other end is placed in the clamping oblique shift assembly of the third axial traction column or the seventh axial traction column, and is clamped and pulled together with the internal optical fiber sleeve.

[0017] This invention also discloses an application method for a distributed fiber optic sensing temperature compensation device based on the dynamic response of hydraulic structures under wave impact, comprising the following steps:

[0018] Step 1: Take two single-mode bare optical fibers and place them side by side on the surface of the hydraulic structure to be tested, reserving enough length as an optical fiber communication segment to connect it to the optical demodulator.

[0019] Step 2: Two single-mode bare optical fibers are used as the vibration sensing fiber and the temperature compensation fiber, respectively. The vibration sensing fiber is laid directly across the entire sensing range and fixed to the surface of the hydraulic structure to be tested using silicone sealant. The temperature compensation fiber is inserted into an outer fiber optic sleeve, and the outer fiber optic sleeve is filled with a silicon-based lubricating layer. The entrance is sealed with a thin plastic film. The outer fiber optic sleeve is fixed to the surface of the hydraulic structure to be tested using silicone sealant. At the starting point, the inner fiber is also fixed together. The temperature compensation fiber is laid and stretched to the position of the first temperature compensation unit.

[0020] Step 3: Align the reserved openings on both sides of the outer sealing box of the temperature compensation unit with the vibration sensing section fiber and the temperature compensation section fiber. Use silicone sealant to fix the bottom of the outer sealing box to the surface of the hydraulic structure to be tested. Extend the temperature compensation section fiber, together with the silicon-based lubricating layer, the outer fiber sleeve, and the silicone fixing adhesive, into the outer sealing box at an appropriate distance. Cut off the silicone fixing adhesive and the outer fiber sleeve. Use a thin plastic film to seal the cut end of the outer fiber sleeve. Introduce the temperature compensation section fiber into the inner fiber sleeve of the temperature compensation unit and lead it out from the other end of the inner fiber sleeve. At this time, the inner sealing box can slide arbitrarily along the temperature compensation section fiber. Align and connect the outer sealing box and the inner sealing box through the vibration isolation module, and ensure that the temperature compensation section fiber on both sides of the first and fourth guide wheels is laid smoothly.

[0021] Step 4: After the temperature compensation fiber is led out from the other side of the inner sealed box, it is re-inserted into the outer fiber optic sleeve at an appropriate distance, and the temperature compensation fiber is led out through the reserved opening in the outer sealed box.

[0022] Step 5: Apply tension to the fiber optic lead-out section of the temperature compensation section inside the inner sealed box to straighten the fiber optic cable of the temperature compensation section inside the temperature compensation unit. Clamp the internal fiber optic sleeve inside the fifth longitudinal traction column by using the clamping and sliding assembly and slide it down a certain distance to fix it. Then, clamp the internal fiber optic sleeve inside the first, second, fourth, sixth, eighth and ninth fastening columns by using the internal fiber optic sleeve clamping assembly.

[0023] Step 6: After passing through the temperature compensation section of the inner sealed box, the optical fiber continues to be inserted into the outer optical fiber sleeve. The reserved opening of the outer optical fiber sleeve is sealed with a thin plastic film. Silicon-based lubricating layer is injected into the temperature compensation section optical fiber and the outer optical fiber sleeve. Silicone glue is used again to fix the optical fiber sleeve to the fixed track inside the outer sealed box. After being led out, silicone glue is used to fix it until it extends to the next temperature compensation unit. Steps 3 to 5 are repeated.

[0024] Step 7: When adjusting two adjacent temperature compensation units, first loosen the internal fiber optic sleeves on the first and second fastening posts of the previous temperature compensation unit, and then clamp the internal fiber optic sleeves in the third axial traction post of the previous temperature compensation unit by using the clamping oblique movement assembly and move obliquely along the direction of the internal fiber optic sleeves to tighten the internal fiber optic sleeves before the third axial traction post.

[0025] Step 8: Loosen the internal fiber optic sleeves on the eighth and ninth fastening posts of the previous temperature compensation unit, loosen the internal fiber optic sleeves on the first and second fastening posts of the next temperature compensation unit, and simultaneously clamp the internal fiber optic sleeves in the seventh axial traction post of the previous temperature compensation unit and the third axial traction post of the next temperature compensation unit using the clamping oblique movement assembly, and move them obliquely along the direction of the internal fiber optic sleeves to tighten the fiber optic sleeves between the seventh axial traction post of the previous temperature compensation unit and the third axial traction post of the next temperature compensation unit.

[0026] Step 9: Loosen the fifth longitudinal traction column of the previous temperature compensation unit so that the tensile stress between the optical fibers in the temperature compensation section before and after the fifth longitudinal traction column is not transmitted.

[0027] Step 10: Continue laying the temperature compensation fiber, connect it to the new temperature compensation unit, and repeat steps 8 and 9 until all temperature compensation units are laid, and then seal the outer sealing box.

[0028] Step 11: Splice the ends of the temperature compensation fiber and the vibration sensing fiber together, and then splice the beginnings of the temperature compensation fiber and the vibration sensing fiber together to the FC interface, and then connect them to the optical signal demodulator.

[0029] Preferably, the method includes the following steps:

[0030] After the construction was completed, the test of the laid optical fiber was carried out. Step excitation load and non-uniform temperature change load were applied to the hydraulic structure to be tested. After confirming that the measurement results were correct, the silicone sealant was sealed at the reserved opening of the outer sealing box of each temperature compensation unit, and the laying of the vibration sensing section optical fiber and the temperature compensation section optical fiber was completed.

[0031] The optical demodulator has a built-in temperature compensation algorithm to process and calculate the measured values ​​of the vibration sensing fiber and the temperature compensation fiber. The specific temperature compensation algorithm is as follows:

[0032] Distributed fiber optic vibration measurement of a floating structure under actual wave load was conducted. The measured value of the fiber optic vibration sensing section at a certain location was ε. d The temperature sensing fiber optic measurement value is ε T The temperature sensing fiber at the temperature compensation unit measures ε. Δ Then the vibration measurement value after temperature compensation at this location is ε = ε d -ε T +ε Δ .

[0033] Beneficial effects:

[0034] 1. This invention, by setting a temperature compensation unit on the surface of a hydraulic structure, utilizes both vibration sensing fiber optic sections and temperature compensation fiber optic sections for measurement. Simultaneously, a prestress adjustment module within the temperature compensation unit adjusts the prestress between the fibers, achieving fiber prestress adjustment. This process completes the measurement of vibration sensing fiber optic values, temperature sensing fiber optic values, and finally, temperature sensing fiber optic values ​​at the temperature compensation unit. These three measurements ultimately determine the vibration measurement value after temperature compensation, making the obtained data more accurate and closer to the true vibration signal. The dustproof and water-proof module isolates the influence of moisture and temperature, and the guiding component guides the fiber optics within the temperature compensation unit as required.

[0035] 2. The present invention connects the inner sealing box and the outer sealing box through an air spring vibration isolator, so that the inner sealing box does not come into contact with the surface of the hydraulic structure under test, thereby reducing external influencing factors.

[0036] 3. The dustproof and waterproof module designed in this invention forms a primary dustproof and waterproof space inside the outer sealed box, and the inner sealed box is a prefabricated sealing component that forms a secondary dustproof and waterproof space inside, ensuring that the sensing fiber optic prestress adjustment module can perform its function well.

[0037] 4. The prestress adjustment module for sensing optical fibers of the present invention effectively adjusts the prestress of the internal optical fiber sleeve and its internal optical fibers by setting multiple fastening columns, longitudinal traction columns, and axial traction columns. The fastening columns are equipped with internal optical fiber sleeve clamping components that can fasten the internal optical fiber sleeve during construction, facilitating the application of prestress. The longitudinal traction columns are equipped with clamping and sliding components that can clamp and slide the internal optical fiber sleeve within the fifth longitudinal traction column, preventing prestress transfer between the internal optical fiber sleeves on both sides of the fifth longitudinal traction column. The fifth longitudinal traction column first moves the sleeve downwards, and after the fourth and sixth fastening columns on both sides are fastened, the fifth longitudinal traction column then moves the sleeve upwards, releasing the optical fiber sleeve. Thus, the prestress between the optical fiber sleeves on both sides of the fifth longitudinal traction column is no longer transferred, separated by the fourth and sixth fastening columns.

[0038] 5. The present invention also provides prestressed springs between the second fastening column and the third axial traction column, and between the seventh axial traction column and the sixth fastening column, respectively, so as to apply appropriate tensile stress to the optical fiber of the temperature compensation section before or after the fifth longitudinal traction column through the prestressed springs.

[0039] 6. In the construction of this device, the first temperature compensation unit is laid first, and the prestress adjustment module of the sensing fiber optic cable inside it is adjusted. Then, the adjacent temperature compensation units are coordinated and adjusted.

[0040] 7. In actual temperature compensation, the present invention can ultimately determine the vibration measurement value based on the vibration sensing fiber measurement value, the temperature sensing fiber measurement value, and the temperature sensing fiber measurement value at the temperature compensation unit. This vibration measurement value is more accurate and reduces the influence of other factors. Attached Figure Description

[0041] Figure 1 Overall structural diagram of the invention;

[0042] Figure 2 This is a cross-sectional view of the optical fiber of the present invention;

[0043] Figure 3 This is a structural diagram of the dustproof and waterproof module;

[0044] Figure 4 This is a detailed structural diagram of the outer sealing box.

[0045] Figure 5 Diagram of the vibration isolation module;

[0046] Figure 6 Layout diagram of internal fiber optic sleeve, guide assembly and sensing fiber prestress adjustment module;

[0047] Figure 7The following is a structural diagram of the internal optical fiber sleeve clamping assembly in an embodiment of the present invention, wherein (a) is a structural diagram of the internal optical fiber sleeve clamping assembly in the first, second, eighth and ninth fastening posts, and (b) is a structural diagram of the internal optical fiber sleeve clamping assembly in the fourth and sixth fastening posts.

[0048] Figure 8 This is a structural diagram of the clamping and sliding assembly according to an embodiment of the present invention;

[0049] Figure 9 This is a structural diagram of the clamping oblique shifting assembly according to an embodiment of the present invention.

[0050] Wherein: 100-Vibration sensing fiber optic cable; 101-Silicone sealant for fixing vibration sensing fiber optic cable; 102-Temperature compensation fiber optic cable; 103-Silicone-based lubricating layer; 104-Outer fiber optic sleeve; 105-Silicone sealant for fixing temperature compensation fiber optic cable; 200-Outer sealing box; 201-Outer sealing cover; 202-Outer sealing box; 203-Fastening bolt assembly; 204-Inner sealing box; 205-Pre-drilled hole; 206-Irregularly shaped boss on outer sealing cover; 207-Irregularly shaped boss on outer sealing box; 300-Outer sealing box support platform; 301-Air spring vibration isolator; 302-Upper connecting platform of inner sealing box; 400-Inner fiber optic sleeve; 500-First guide wheel; 501-Second guide wheel; 502-Third guide wheel; 503- Fourth guide wheel; 504-First guide wheel bracket; 505-Fourth guide wheel bracket; 506-Second guide wheel bracket; 507-Third guide wheel bracket; 600-First fastening post; 601-Second fastening post; 602-Third axial traction post; 603-Fourth fastening post; 604-Fifth longitudinal traction post; 605-Sixth fastening post; 606-Seventh axial traction post; 607-Eighth fastening post; 608-Ninth fastening post; 700-First prestressed spring; 701-Second prestressed spring; 800-First threaded post; 801-Clamping block; 802-Second threaded post; 803-Second slider; 804-Electric slide rail; 805-Finger cylinder; 900-First connecting plate; 901-Second connecting plate. Detailed Implementation

[0051] The invention will now be further described with reference to the accompanying drawings.

[0052] like Figures 1 to 8As shown, this invention discloses a distributed optical fiber sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact. Two single-mode bare optical fibers are arranged side-by-side on the surface of the hydraulic structure under test, laid parallel and adjacent to each other, with sufficient length reserved as an optical fiber communication segment for connection to an optical signal demodulator. The two single-mode bare optical fibers serve as the vibration sensing fiber and the temperature compensation fiber, respectively, and are connected to the optical demodulator via the communication fiber to form an optical signal demodulation module. The device also includes several temperature compensation units spaced apart on the surface of the hydraulic structure under test. The vibration sensing fiber 100 and the temperature compensation fiber 102 are connected through these temperature compensation units. Each temperature compensation unit includes a dustproof and water-proof module, a vibration isolation module, and a sensing fiber prestress adjustment module.

[0053] The vibration sensing fiber 100 is fixed to the surface of the structure by the vibration sensing fiber fixing silicone 101 and passes directly through the temperature compensation unit. When laying the temperature compensation fiber 102, it first passes through the outer fiber optic sleeve 104. A base lubrication layer 103 is set between the fiber and the sleeve. The outer fiber optic sleeve 104 is fixed to the surface of the structure by the temperature compensation fiber fixing silicone 105. The temperature compensation fibers on both sides are connected by the temperature compensation unit.

[0054] The dustproof and water-proof module includes an outer sealing box 200 and an inner sealing box 204. The outer sealing box 200 is fixed to the surface of the hydraulic structure to be tested, and the inner sealing box 204 is installed inside it. The inner sealing box 204 is a prefabricated sealing component. The outer sealing box 200 and the inner sealing box 204 are connected by a vibration isolation module, and the inner sealing box 200 does not contact the surface of the hydraulic structure to be tested. The inner sealing box 204 is equipped with a guide component and a sensing fiber prestress adjustment module. The sensing fiber prestress adjustment module is used to adjust the prestress of the sensing fiber, and the guide component is used to guide and pull the temperature compensation section fiber entering the inner sealing box to the reserved outlet position of the outer sealing box.

[0055] The outer sealing box 200 consists of an outer sealing box 202, an outer sealing cover 201, a sealing ring, and a fastening bolt assembly 203. The outer sealing box 202 is fixed to the surface of the structure to be tested with silicone sealant. The silicone sealant seals the pre-reserved hole 205 at the bottom side of the outer sealing box 202 through which the optical fiber is inserted. The gap between the outer sealing box 202 and the outer sealing cover 201 is filled by the sealing ring. The fastening bolt assembly 203 applies pressure to the sealing ring, so that a primary dustproof and waterproof space is formed inside the outer sealing box 202. The outer sealing cover 201 has irregularly shaped protrusions 206 extending inward around its four perimeter. The cross-section of the irregularly shaped protrusions 206 bends inward on both sides. The sealing ring is fixed to the irregularly shaped protrusions 206 by the bent barbs on both sides. The outer sealing box 202 has irregularly shaped protrusions 207 extending inward from the inner side of its upper edge. The fastening bolt assembly 203 applies pressure around the entire outer sealing box 202, so that the irregularly shaped protrusions 207 and 206 of the outer sealing box 202 squeeze and shape the sealing ring to form a seal.

[0056] In this embodiment, a first connecting plate 900 is fixed on the outer sealing cover 201. A second connecting plate 901 is fixed on the outer sealing box 202. The fastening bolt assembly 203 includes a fastening bolt and a nut. The first connecting plate 900 and the second connecting plate 901 are fastened together by the fastening bolt and the nut, sealing the outer sealing cover 201 onto the outer sealing box 202, thus completing the sealing operation of the outer sealing box 200.

[0057] The inner sealing box 204 is a prefabricated sealing component, forming a two-stage dustproof and waterproof space inside to ensure that the sensing fiber optic prestress adjustment module can function properly.

[0058] The vibration isolation module of the temperature compensation unit includes two lower support platforms 300 on both sides of the outer sealing box 202, two air spring vibration isolators 301 on both sides, and two upper connecting platforms 302 on both sides of the inner sealing box 204. The inner sealing box 204 is connected to the outer sealing box 200 through the vibration isolation module to avoid direct contact with the hydraulic structure under test. In this invention, the two lower support platforms 300 on both sides of the outer sealing box 200 and the two upper connecting platforms 302 on both sides of the inner sealing box should be located in a horizontal plane.

[0059] The vibration sensing fiber 100 and the temperature compensation fiber 102 are inserted into the temperature compensation unit through the reserved hole 205 of the outer sealing box 202. The multi-layer structure of the temperature compensation fiber 102 changes after entering the temperature compensation unit. That is, the silicone sealant 105 for fixing the temperature compensation fiber and the outer fiber optic sleeve 104 are cut off. The temperature compensation fiber 102 extends further into the inner fiber optic sleeve 400 of the temperature compensation unit to prevent structural vibration from being transmitted to the inner sealing box 204. The cut-off point of the outer fiber optic sleeve 104 of the temperature compensation fiber is sealed by a lightweight and deformable film 106 to prevent the silicone lubricating layer 103 from overflowing.

[0060] According to the connection sequence of the temperature compensation fiber 102, the guiding assembly is divided into a first guide wheel 500, a second guide wheel 501, a third guide wheel 502, and a fourth guide wheel 503. The first guide wheel 500 guides the temperature compensation fiber 102 obliquely upward from the surface of the hydraulic structure to the second guide wheel 501. The second guide wheel 501 guides the temperature compensation fiber 102 to the third guide wheel 502. The third guide wheel 502 guides the temperature compensation fiber 102 obliquely downward to the fourth guide wheel 503. The fourth guide wheel 503 guides the temperature compensation fiber 102 back to the surface of the hydraulic structure. The first and fourth guide wheels 500 and 503 are fixed to the outside of the inner sealing box 204 by brackets 504 and 505. The second and third guide wheels 501 and 502 are fixed to the inside of the inner sealing box 204 by brackets 506 and 507. The second and third guide wheels 501 and 502 are horizontally arranged, and the external fiber optic sleeve 400 between the first guide wheel 500 and the second guide wheel 501 and the external fiber optic sleeve 400 between the third guide wheel 502 and the fourth guide wheel 503 are arranged in an "X" shape.

[0061] The temperature compensation unit's sensing fiber optic prestress adjustment module, see [link / reference]. Figure 6 It includes a first fastening post 600, a second fastening post 601, a third axial traction post 602, a fourth fastening post 603, a fifth longitudinal traction post 604, a sixth fastening post 605, a seventh axial traction post 606, an eighth fastening post 607, and a ninth fastening post 608. The external fiber optic sleeve 400 between the first guide wheel 500 and the second guide wheel 501 sequentially passes through the first fastening post 600, the second fastening post 601, and the third axial traction post 602; the external fiber optic sleeve 400 between the third guide wheel 502 and the fourth guide wheel 503 sequentially passes through the seventh axial traction post 606, the eighth fastening post 607, and the ninth fastening post 608; and the external fiber optic sleeve 400 between the second and third guide wheels 501 and 502 sequentially passes through the fourth fastening post 603, the fifth longitudinal traction post 604, and the sixth fastening post 605.

[0062] According to the order of fiber penetration, it passes through the first fastening post 600, the second fastening post 601, the third axial traction post 602, the fourth fastening post 603, the fifth longitudinal traction post 604, the sixth fastening post 605, the seventh axial traction post 606, the eighth fastening post 607, and the ninth fastening post 608 in sequence.

[0063] The first fastening post 600, the second fastening post 601, the fourth fastening post 603, the sixth fastening post 605, the eighth fastening post 607, and the ninth fastening post 608 are equipped with internal fiber optic sleeve clamping assemblies for clamping the internal fiber optic sleeve 400 located in the corresponding fastening post.

[0064] In this embodiment, the internal fiber optic sleeve clamping assembly can be implemented using a first threaded post 800. The upper end of the first threaded post 800 is connected to a corresponding fastening post via a bearing. The upper and lower ends of the first threaded post 800 are provided with reverse threads, and the reverse thread mating point is located at the point where the internal fiber optic sleeve 400 passes through. Clamping blocks 801 are threadedly connected to the reverse threads at the upper and lower ends, respectively. When a pair of clamping blocks 801 clamp the internal fiber optic sleeve 400, the opposing surfaces of the clamping blocks 801 match the extension direction of the internal fiber optic sleeve 400. That is, when the clamping blocks 801 in the fourth fastening post 603 and the sixth fastening post 605 clamp the internal fiber optic sleeve 400, the clamping blocks 801 are horizontally positioned because the second and third guide wheels 501 and 502 are horizontally positioned. However, for the clamping blocks 801 in the first fastening post 600, the second fastening post 601, the eighth fastening post 607, and the ninth fastening post 608, the opposing surfaces are inclined surfaces, matching the extension direction of the internal fiber optic sleeve 400. (See [reference needed]). Figure 7 .

[0065] A clamping and sliding assembly is provided inside the fifth longitudinal traction column 604, see [link / reference]. Figure 8 This mechanism is used to clamp and slide the internal fiber optic sleeve 400 within the fifth longitudinal traction column 604. In this embodiment, the clamping and sliding assembly can be implemented using a second threaded post 802. The upper end of the second threaded post 802 is connected to the fifth longitudinal traction column 604 via a bearing. A second slider 803 is threaded onto the second threaded post 802. The internal fiber optic sleeve 400 passes through the second slider 803 and does not contact the second threaded post 802. The second threaded post 802 has only a unidirectional thread, and the second slider 803 can slide up and down by rotating the second threaded post 802, further causing the internal fiber optic sleeve 400 to move slightly up and down, thus achieving stretching.

[0066] Clamping and oblique movement components are provided inside the third axial traction column 602 and the seventh axial traction column 606. These components clamp the internal fiber optic sleeve 400 inside the third axial traction column 602 and the seventh axial traction column 606 and move obliquely along the direction of the internal fiber optic sleeve 400, thereby tightening the internal fiber optic sleeve 400 before the third axial traction column 602 and after the seventh axial traction column 606. In this embodiment, the clamping and oblique movement components can be implemented by an electric slide rail 804 or a telescopic cylinder. The electric slide rail 804 or the telescopic cylinder is disposed inside the third axial traction column 602 and the seventh axial traction column 606 and is arranged along the extension direction of the internal fiber optic sleeve 400. The electric slide rail 804 or the telescopic cylinder can be disposed on the inner wall of the third axial traction column 602 and the seventh axial traction column 606, and a finger cylinder 805 is disposed thereon. The actuating end of the finger cylinder 805 is aligned with the internal fiber optic sleeve 400 penetrating the third axial traction column 602 and the seventh axial traction column 606. See [reference needed]. Figure 9 .

[0067] In addition, a first prestressed spring 700 and a second prestressed spring 701 are provided, respectively positioned between the second fastening post 601 and the third axial traction post 602, and between the seventh axial traction post 606 and the eighth fastening post 607. One end of the first prestressed spring 700 is connected to the column body of the second fastening post 601, and the other end is placed in the clamping and tilting assembly of the third axial traction post 602, where it is clamped and pulled together with the internal fiber optic sleeve and the internal fiber. One end of the second prestressed spring 701 is connected to the column body of the eighth fastening post 607, and the other end is placed in the clamping and tilting assembly of the seventh axial traction post 606, where it is clamped and pulled together with the internal fiber optic sleeve and the internal fiber.

[0068] The internal fiber optic sleeve clamping assembly, clamping sliding assembly, and clamping oblique sliding assembly can be precisely controlled by a PLC controller. The first threaded post 800 and the second threaded post 802 can be precisely driven to rotate by a PLC-controlled drive motor. The electric slide rail 804 / telescopic cylinder and finger cylinder 805 can be precisely controlled by the PLC through electrical signals. These are conventional techniques in the field and are not the focus of this invention; therefore, they will not be elaborated further here.

[0069] In response to the above-mentioned structure, the present invention also discloses a construction method for a distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact, comprising the following steps:

[0070] The first step is to take two ordinary single-mode bare optical fibers and place them side by side on the surface of the building to be tested on the water, reserving enough length as an optical fiber communication segment so that it can be connected to the optical demodulator.

[0071] The second step involves using one ordinary single-mode bare optical fiber as the vibration sensing fiber 100 and the other as the temperature compensation fiber 102. The vibration sensing fiber 100 is laid directly across the entire sensing range and fixed to the surface of the hydraulic structure under test using silicone sealant 101. The temperature compensation fiber 102 is inserted into the fiber optic sleeve 104 and filled with silicon-based lubricant 103. The entrance is sealed with a thin plastic film 106. The outer fiber optic sleeve 104 is fixed to the surface of the structure under test using silicone sealant 105. At the starting point, the inner fiber optic cable must also be fixed together to prevent the temperature compensation fiber from moving. The temperature compensation fiber 102 is then laid and stretched to the first temperature compensation unit.

[0072] Thirdly, align the pre-drilled openings 205 on both sides of the outer sealing box 200 of the temperature compensation unit with the vibration sensing fiber 100 and the temperature compensation fiber 102. Use silicone sealant to fix the bottom of the outer sealing box 202 of the outer sealing box 200 to the surface of the structure to be tested. Extend the temperature compensation fiber 102, along with its silicon-based lubricating layer 103, outer fiber optic sleeve 104, and silicone sealant 105 for fixing the temperature compensation fiber 102, into the outer sealing box 202 a suitable distance. Cut off the silicone sealant 105 for fixing the temperature compensation fiber 102 and the outer fiber optic sleeve 104. A thin plastic film is used to seal the cut end of the external fiber optic sleeve 104, ensuring that the internal fiber optic sleeve clamping assembly, clamping sliding assembly, and clamping oblique sliding assembly of the inner sealing box 204 are in a loose state. The temperature compensation section fiber optic cable 102 is introduced into one end of the internal fiber optic sleeve 400 of the temperature compensation unit sensing fiber optic prestress adjustment module and led out from the other end of the internal fiber optic sleeve 400. At this time, the inner sealing box 204 should be able to slide freely along the temperature compensation section fiber optic cable 102. During the sliding process, the part of the internal fiber optic sleeve 400 that passes through can be sealed by a rubber ring. The lower support platforms 300 on both sides of the outer sealing box 200, the air spring vibration isolators 301 on both sides, and the upper connecting platforms 302 on both sides of the inner sealing box 204 are aligned and connected to ensure that the fiber optic cables on both sides of the first and fourth guide wheels 500 and 503 are laid smoothly.

[0073] Fourth step: After the temperature compensation section fiber 102 is led out from the other end of the sensing fiber prestress adjustment module of the temperature compensation unit, it is re-inserted into the external fiber optic sleeve 104 at an appropriate distance, and the temperature compensation section fiber 102 is led out through the reserved opening 205 along the track.

[0074] Fifth step: Check that the internal fiber optic sleeves 400 at the first and fourth guide wheels 500 and 503 are in place, and check that the outer sealing box 200 and inner sealing box 204 are in place and secure.

[0075] Step 6: Apply appropriate tension to the lead-out section of the temperature compensation fiber 102 to straighten the temperature compensation fiber 102 inside the temperature compensation unit. Then, clamp the internal fiber sleeve 400 inside the fifth longitudinal traction column 604 with the clamping and sliding assembly and slide it a certain distance to fix it. At this time, the temperature compensation fiber 102 at the outlet will be pulled back into the temperature compensation unit by a small amount.

[0076] Step 7: The internal fiber optic sleeve 400 inside the first, second, fourth, sixth, eighth and ninth fastening columns is clamped by the internal fiber optic sleeve clamping assembly. This can lock the internal fiber optic sleeve 400 and the temperature compensation fiber 102 inside it. The second and eighth fastening columns 601 and 607 fix one end of the two prestressed springs 701 and 702 to the column body.

[0077] Step 8: Use a thin plastic film to seal the external fiber optic sleeve 104 at the reserved opening 205. Inject a silicon-based lubricating layer 103 into the external fiber optic sleeve 104 of the temperature compensation section fiber 102 at the outlet. Then, use silicone sealant 105 to fix the external fiber optic sleeve 104 to the inner fixing track of the outer sealing box 200. After leading out, continue to use silicone sealant to fix it until it reaches the next temperature compensation unit, and repeat steps 3 to 7.

[0078] In the ninth step, when adjusting two adjacent temperature compensation units, first loosen the internal fiber optic sleeves 400 on the first and second fastening posts 600 and 601 of the previous temperature compensation unit, and then clamp the internal fiber optic sleeves 400 inside the third axial traction post 602 by using the clamping oblique movement assembly and move obliquely along the direction of the internal fiber optic sleeves 400 to tighten the fiber optic sleeves 400 before the third axial traction post 602.

[0079] Step 10: Loosen the internal fiber optic sleeves 400 on the eighth and ninth fastening posts 607 and 608 of the previous temperature compensation unit, and loosen the internal fiber optic sleeves 400 on the first and second fastening posts 600 and 601 of the next temperature compensation unit. At the same time, clamp the internal fiber optic sleeves 400 in the seventh axial traction post 606 of the previous temperature compensation unit and the third axial traction post 602 of the next temperature compensation unit using the clamping oblique movement assembly, and move them obliquely along the direction of the internal fiber optic sleeves 400 to tighten the fiber optic sleeves 400 between the seventh axial traction post 606 of the previous temperature compensation unit and the third axial traction post 602 of the next temperature compensation unit.

[0080] Step 11: Release the fifth longitudinal traction column 604 of the previous temperature compensation unit so that the tensile stress between the temperature compensation fiber 102 before and after the fifth longitudinal traction column 604 is not transmitted.

[0081] Step 12: Continue laying the temperature compensation fiber 102, connect it to the new temperature compensation unit, and repeat steps 10 and 11 until all temperature compensation units are connected.

[0082] Step 13: The tail ends of the temperature compensation fiber 102 and the vibration sensing fiber 100 are fused together, and the heads of the temperature compensation fiber 102 and the vibration sensing fiber 100 are fused together to the FC interface, and then connected to the optical demodulator.

[0083] For the above-mentioned construction process, the present invention utilizes this device for a distributed fiber optic sensing temperature compensation method, which specifically includes the following steps:

[0084] Test the laid optical fibers, apply step excitation load and non-uniform temperature change load to the hydraulic structure, and after confirming that the measurement results are correct, seal the reserved opening 205 of the outer sealing box 200 of each temperature compensation unit with silicone sealant, cover with outer sealing cover 201, tighten bolts 203, and complete the laying of vibration sensing section optical fiber 100 and temperature compensation section optical fiber 102.

[0085] The optical demodulator has a built-in temperature compensation algorithm to process and calculate the measured values ​​of the vibration sensing fiber and the temperature compensation fiber. The temperature compensation algorithm is as follows:

[0086] Distributed fiber optic vibration measurement of a floating structure under actual wave load was conducted. The measured value of vibration sensing fiber 100 at a certain location was ε. d The temperature sensing fiber optic cable 102 measures ε. T The temperature sensing fiber at the temperature compensation unit measures ε. V Then the vibration measurement value after temperature compensation at this location is ε = ε d -ε T +ε Δ .

[0087] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact, characterized in that, It includes a sensing optical fiber, which is connected to an optical demodulator via a communication optical fiber. The sensing optical fiber includes a vibration sensing section optical fiber and a temperature compensation section optical fiber, which are laid parallel and adjacent to each other on the surface of the hydraulic structure to be tested. It also includes a number of temperature compensation units spaced apart on the surface of the hydraulic structure to be tested. The temperature compensation unit includes a dustproof and waterproof module, a guiding component, and a sensing optical fiber prestress adjustment module. The dustproof and water-proof module includes an outer sealing box and an inner sealing box. The outer sealing box is fixed to the surface of the hydraulic structure to be tested, and an inner sealing box is provided inside it. The inner sealing box is a prefabricated sealing component. The outer sealing box and the inner sealing box are connected by a vibration isolation module, and the inner sealing box does not contact the surface of the hydraulic structure to be tested. The inner sealing box is provided with a guide component and a sensing fiber prestress adjustment module. The sensing fiber prestress adjustment module is used to adjust the prestress of the sensing fiber. The guide component is used to guide and pull the temperature compensation section fiber entering the inner sealing box to the reserved outlet position of the outer sealing box. The vibration sensing fiber passes directly through the outer sealed box. The left and right temperature compensation fiber sections are connected by a temperature compensation unit. After passing through the outer sealed box, they are guided by a guide component in the inner sealed box and connected to the sensing fiber prestress adjustment module. The prestress of the temperature compensation fiber section in the inner sealed box is adjusted by the sensing fiber prestress adjustment module. The vibration sensing fiber is fixed to the surface of the hydraulic structure under test with silicone sealant, and passes directly through the outer sealing box and is sealed with silicone sealant. The temperature compensation fiber on the outside of the temperature compensation unit is inserted into the outer fiber optic sleeve, and a silicon-based lubricating layer is provided between the temperature compensation fiber and the outer fiber optic sleeve. The outer fiber optic sleeve is fixed to the surface of the hydraulic structure with silicone sealant. The temperature compensation fiber on the inside of the temperature compensation unit is cut off from the outer fiber optic sleeve after entering the temperature compensation unit, and extends further into the inner fiber optic sleeve of the temperature compensation unit. At the cut-off point of the temperature compensation fiber optic sleeve, a thin film is used to seal it to prevent the silicon-based lubricating layer from overflowing.

2. The distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in claim 1, characterized in that, The vibration isolation module includes lower support platforms on both sides of the outer sealing box, air spring vibration isolators on both sides, and upper connecting platforms on both sides of the inner sealing box. The air spring vibration isolators on both sides are arranged between the lower support platforms and the upper connecting platforms, and the inner sealing box is connected to the outer sealing box through the vibration isolation module.

3. The distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in claim 2, characterized in that, The guiding assembly includes a first guide wheel, a second guide wheel, a third guide wheel, and a fourth guide wheel. The first and fourth guide wheels are mounted on the outside of the inner sealed box via brackets, while the second and third guide wheels are mounted on the inside of the inner sealed box via brackets. The first guide wheel guides the temperature compensation fiber optic section entering the outer sealed box obliquely upward from the surface of the hydraulic structure to the second guide wheel. The second guide wheel guides the temperature compensation fiber optic section to the third guide wheel. The third guide wheel guides the temperature compensation fiber optic section downward obliquely to the fourth guide wheel. The fourth guide wheel guides the temperature compensation fiber optic section back to the surface of the hydraulic structure. The second and third guide wheels are horizontally arranged, and the external fiber optic sleeves between the first and second guide wheels and between the third and fourth guide wheels are arranged in an "X" shape.

4. The distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in claim 3, characterized in that, The sensing fiber optic prestress adjustment module includes a first fastening post, a second fastening post, a third axial traction post, a fourth fastening post, a fifth longitudinal traction post, a sixth fastening post, a seventh axial traction post, an eighth fastening post, and a ninth fastening post; the external fiber optic sleeve between the first guide wheel and the second guide wheel sequentially passes through the first fastening post, the second fastening post, and the third axial traction post; the external fiber optic sleeve between the third guide wheel and the fourth guide wheel sequentially passes through the seventh axial traction post, the eighth fastening post, and the ninth fastening post; the external fiber optic sleeve between the second and third guide wheels sequentially passes through the fourth fastening post, the fifth longitudinal traction post, and the sixth fastening post. The first, second, fourth, sixth, eighth, and ninth fastening posts are equipped with internal fiber optic sleeve clamping assemblies for clamping the internal fiber optic sleeves located within the corresponding fastening posts. The fifth longitudinal traction post is equipped with a clamping sliding assembly for clamping and sliding the internal fiber optic sleeve within the fifth longitudinal traction post. The third and seventh axial traction posts are equipped with clamping oblique sliding assemblies for clamping and obliquely moving the internal fiber optic sleeves within the third and seventh axial traction posts, thereby tightening the fiber optic sleeves and their internal fibers before the third axial traction post and after the seventh axial traction post.

5. A distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in claim 4, characterized in that, The internal fiber optic sleeve clamping assembly includes a first threaded post. The upper end of the first threaded post is connected to a corresponding fastening post through a bearing. The upper and lower ends of the first threaded post are provided with reverse threads. The reverse thread mating point is located at the position where the internal fiber optic sleeve passes through. Clamping blocks are threadedly connected to the reverse threads at the upper and lower ends respectively. When a pair of clamping blocks clamp the internal fiber optic sleeve, the opposite surfaces of the clamping blocks match the extension direction of the internal fiber optic sleeve.

6. The distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact according to claim 4, characterized in that, The clamping and sliding assembly includes a second threaded post, the upper end of which is connected to a fifth longitudinal traction post via a bearing. A second slider is threaded onto the second threaded post, and the internal optical fiber sleeve passes through the second slider without contacting the second threaded post.

7. A distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in claim 4, characterized in that, The clamping and tilting assembly includes an electric slide rail or a telescopic cylinder that extends and retracts along the direction of the inner optical fiber sleeve, both disposed within the third axial traction column and the seventh axial traction column. A finger cylinder is provided on the actuating end of the electric slide rail or the telescopic cylinder, and the actuating end of the finger cylinder is aligned with the inner optical fiber sleeve that passes through the third axial traction column and the seventh axial traction column.

8. A distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact according to claim 4, characterized in that, Prestressed springs are also provided between the second fastening column and the third axial traction column, and between the seventh axial traction column and the eighth fastening column. One end of the prestressed spring is connected to the column body of the second fastening column or the eighth fastening column, and the other end is placed in the clamping oblique shift assembly of the third axial traction column or the seventh axial traction column, and is clamped and pulled together with the internal optical fiber sleeve.

9. An application method of a distributed fiber optic sensing temperature compensation device for the dynamic response of hydraulic structures under wave impact as described in any one of claims 4 to 8, characterized in that, Includes the following steps: Step 1: Take two single-mode bare optical fibers and place them side by side on the surface of the hydraulic structure to be tested, reserving enough length as an optical fiber communication segment to connect it to the optical demodulator. Step 2: Two single-mode bare optical fibers are used as the vibration sensing fiber and the temperature compensation fiber, respectively. The vibration sensing fiber is laid directly across the entire sensing range and fixed to the surface of the hydraulic structure to be tested using silicone sealant. The temperature compensation fiber is inserted into an outer fiber optic sleeve, and the outer fiber optic sleeve is filled with a silicon-based lubricating layer. The entrance is sealed with a thin plastic film. The outer fiber optic sleeve is fixed to the surface of the hydraulic structure to be tested using silicone sealant. At the starting point, the inner fiber is also fixed together. The temperature compensation fiber is laid and stretched to the position of the first temperature compensation unit. Step 3: Align the reserved openings on both sides of the outer sealing box of the temperature compensation unit with the vibration sensing section fiber and the temperature compensation section fiber. Use silicone sealant to fix the bottom of the outer sealing box to the surface of the hydraulic structure to be tested. Extend the temperature compensation section fiber, together with the silicon-based lubricating layer, the outer fiber sleeve, and the silicone fixing adhesive, into the outer sealing box at an appropriate distance. Cut off the silicone fixing adhesive and the outer fiber sleeve. Use a thin plastic film to seal the cut end of the outer fiber sleeve. Introduce the temperature compensation section fiber into the inner fiber sleeve of the temperature compensation unit and lead it out from the other end of the inner fiber sleeve. At this time, the inner sealing box can slide arbitrarily along the temperature compensation section fiber. Align and connect the outer sealing box and the inner sealing box through the vibration isolation module, and ensure that the temperature compensation section fiber on both sides of the first and fourth guide wheels is laid smoothly. Step 4: After the temperature compensation fiber is led out from the other side of the inner sealed box, it is re-inserted into the outer fiber optic sleeve at an appropriate distance, and the temperature compensation fiber is led out through the reserved opening in the outer sealed box. Step 5: Apply tension to the fiber optic lead-out section of the temperature compensation section inside the inner sealed box to straighten the fiber optic cable of the temperature compensation section inside the temperature compensation unit. Clamp the internal fiber optic sleeve inside the fifth longitudinal traction column by using the clamping and sliding assembly and slide it down a certain distance to fix it. Then, clamp the internal fiber optic sleeve inside the first, second, fourth, sixth, eighth and ninth fastening columns by using the internal fiber optic sleeve clamping assembly. Step 6: After passing through the temperature compensation section of the inner sealed box, the optical fiber continues to be inserted into the outer optical fiber sleeve. The reserved opening of the outer optical fiber sleeve is sealed with a thin plastic film. Silicon-based lubricating layer is injected into the temperature compensation section optical fiber and the outer optical fiber sleeve. Silicone glue is used again to fix the optical fiber sleeve to the fixed track inside the outer sealed box. After being led out, silicone glue is used to fix it until it extends to the next temperature compensation unit. Steps 3 to 5 are repeated. Step 7: When adjusting two adjacent temperature compensation units, first loosen the internal fiber optic sleeves on the first and second fastening posts of the previous temperature compensation unit, and then clamp the internal fiber optic sleeves in the third axial traction post of the previous temperature compensation unit by using the clamping oblique movement assembly and move obliquely along the direction of the internal fiber optic sleeves to tighten the internal fiber optic sleeves before the third axial traction post. Step 8: Loosen the internal fiber optic sleeves on the eighth and ninth fastening posts of the previous temperature compensation unit, loosen the internal fiber optic sleeves on the first and second fastening posts of the next temperature compensation unit, and simultaneously clamp the internal fiber optic sleeves in the seventh axial traction post of the previous temperature compensation unit and the third axial traction post of the next temperature compensation unit using the clamping oblique movement assembly, and move them obliquely along the direction of the internal fiber optic sleeves to tighten the fiber optic sleeves between the seventh axial traction post of the previous temperature compensation unit and the third axial traction post of the next temperature compensation unit. Step 9: Loosen the fifth longitudinal traction column of the previous temperature compensation unit so that the tensile stress between the optical fibers in the temperature compensation section before and after the fifth longitudinal traction column is not transmitted. Step 10: Continue laying the temperature compensation fiber, connect it to the new temperature compensation unit, and repeat steps 8 and 9 until all temperature compensation units are laid, and then seal the outer sealing box. Step 11: Splice the ends of the temperature compensation fiber and the vibration sensing fiber together, and then splice the beginnings of the temperature compensation fiber and the vibration sensing fiber together to the FC interface, and then connect them to the optical signal demodulator.

10. The application method according to claim 9, characterized in that, Includes the following steps: After the construction was completed, the test of the laid optical fiber was carried out. Step excitation load and non-uniform temperature change load were applied to the hydraulic structure to be tested. After confirming that the measurement results were correct, the silicone sealant was sealed at the reserved opening of the outer sealing box of each temperature compensation unit, and the laying of the vibration sensing section optical fiber and the temperature compensation section optical fiber was completed. The optical demodulator has a built-in temperature compensation algorithm to process and calculate the measured values ​​of the vibration sensing fiber and the temperature compensation fiber. The specific temperature compensation algorithm is as follows: Distributed fiber optic vibration measurement of a floating structure under actual wave load was conducted. The measured value of the fiber optic vibration sensing section at a certain location was ε. d The temperature sensing fiber optic measurement value is ε T The temperature sensing fiber at the temperature compensation unit measures ε. Δ Then the vibration measurement value after temperature compensation at this location is ε = ε d -ε T +ε Δ .

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