Experimental device for acquiring strain compensation coefficient and operation and coefficient acquisition method thereof

Abstract

The present application relates to the technical field of communication cable parameter measurement, and particularly relates to an experimental device for obtaining a strain compensation coefficient, an operation method of the experimental device and a coefficient obtaining method. The experimental device comprises a monitor, a first fastening member, a second fastening member, reinforcing members and a weighting assembly. The monitor is used to obtain the Brillouin frequency shift of an optical fiber. The first fastening member is provided with at least two first connecting portions arranged at intervals. The second fastening member is connected with the first connecting portions to form a fastening gap with the first fastening member for pressing the optical fiber. The reinforcing members are connected with the second fastening member one by one. Each reinforcing member is connected with the first fastening member. The reinforcing member is further provided with a second connecting portion for connecting with an armored portion. The weighting assembly is used to connect with the optical fiber between two adjacent fastening gaps to provide different weights. The present application can obtain a more accurate strain compensation coefficient to make the measurement result more reliable in the process of directly measuring the strain of the armored optical fiber.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication cable parameter measurement, in particular to an experimental device for obtaining a strain compensation coefficient and an operation method and a coefficient obtaining method thereof. BACKGROUND

[0002] Distributed optical fiber sensing technology is a monitoring technology that uses optical fibers as both sensors and transmission channels for measuring signals. Compared with point-type collection and monitoring methods, it has the advantages of being distributed, long-distance, corrosion-resistant, and anti-interference. To adapt to the extensive construction environment of a construction site and better monitor the stress and strain of a building, the monitoring optical fibers used at the construction site are mostly armored optical fibers with steel strands. In strain monitoring, the properties of the sheath and armored materials of the optical fiber determine the effectiveness of the optical fiber monitoring.

[0003] It is an important issue to protect optical fibers from damage and maintain their sensitivity to strain and temperature. There is a trade-off between strain sensitivity and fiber protection. Coating layers, sheaths, and armored optical fibers containing steel strands are widely used in distributed optical fiber sensors. Optical fibers themselves are a sensing medium that can be embedded in structures sensitive to environmental changes. The coating layer on the surface, the armored material inside, and the sheath outside are all possible protection methods. Since these protective layers were originally designed for optical fiber communication systems rather than sensing systems, these protective measures can transmit physical quantities such as temperature and stress, but they also affect the results of optical fiber monitoring and introduce additional strain errors in the measurement.

[0004] To solve the above-mentioned problems related to optical fiber strain monitoring data error compensation, some scholars have also provided some solutions. For example, patent CN201911193571.0 provides a distributed optical fiber sensor measurement point positioning error compensation method. Patent CN201811466896.7 discloses a concrete dam distributed optical fiber temperature measurement data error compensation method. The existing technologies mainly solve the problem of distributed optical fiber sensor measurement point positioning error caused by optical path changes and the DTS temperature measurement data error compensation method of optical fibers, but they do not consider the measurement errors caused by optical fiber sheaths and armored materials in engineering, and lack strain monitoring data error compensation devices and technologies for armored optical fibers in engineering applications. Therefore, how to directly monitor armored optical fibers and obtain more accurate strain monitoring results is an urgent problem to be solved. SUMMARY

[0005] The application provides an experimental device for obtaining a strain compensation coefficient and an operation method and a coefficient obtaining method.

[0006] The application is achieved by the following technical solutions:

[0007] In a first aspect, the application provides an experimental device for obtaining a strain compensation coefficient, comprising:

[0008] a monitor configured to obtain a Brillouin frequency shift of the optical fiber;

[0009] a first clamping member provided with at least two first connecting portions arranged at intervals;

[0010] a second clamping member connected with the first connecting portions to form clamping gaps with the first clamping member for pressing the stripped optical fiber portion of the armored optical fiber;

[0011] a plurality of reinforcing members respectively connected with the second clamping members one by one, each of the reinforcing members being connected with the first clamping member, and each of the reinforcing members being further provided with a second connecting portion for connecting with the stripped armored portion of the armored optical fiber;

[0012] a weighting assembly configured to connect with the optical fiber between two adjacent clamping gaps to provide different weights when the optical fiber is pressed by the second clamping member.

[0013] In some embodiments of the first aspect, the first clamping member and / or the second clamping member is provided with a circular-arc-shaped groove adapted to the optical fiber portion.

[0014] In some embodiments of the first aspect, the reinforcing member is provided with a clearance hole for the optical fiber to pass through and a plurality of fixed small holes circumferentially distributed about the clearance hole, the fixed small holes being used for threading the steel strands stripped from the armored optical fiber.

[0015] In some embodiments of the first aspect, the reinforcing member is provided with a welding portion for welding the steel strands.

[0016] In some embodiments of the first aspect, the weighting assembly comprises:

[0017] a weight;

[0018] a weight disc for placing the weight;

[0019] a cable connected to the weight disc and used to connect with the armored fiber.

[0020] In a second aspect, the present application provides an operating method of an experimental device for obtaining strain compensation coefficients, comprising the following steps:

[0021] setting up a first experimental device and a second experimental device;

[0022] stripping the armored fiber to form a plurality of stripped segments;

[0023] twisting the armored fiber into a serpentine shape and making each stripped segment correspond to a position of the first connecting part;

[0024] connecting all the second fastening parts with the first fastening parts in the first experimental device so that each stripped segment is located in the fastening gap;

[0025] connecting the stripped armored part of the armored fiber with the reinforcing part of the first experimental device and making the reinforcing part connect with the corresponding first fastening part and second fastening part;

[0026] connecting both ends of the armored fiber to the monitor of the first experimental device and connecting a plurality of weighted components to the armored fiber segment between each two fastening gaps respectively;

[0027] twisting the non-armored fiber into the same serpentine shape as the armored fiber;

[0028] connecting all the second fastening parts with the first fastening parts in the second experimental device so that the plurality of segments of the non-armored fiber are located in the fastening gap;

[0029] connecting the reinforcing part of the second experimental device with the corresponding first fastening part and second fastening part;

[0030] connecting both ends of the non-armored fiber to the monitor of the second experimental device and connecting a plurality of weighted components to the non-armored fiber segment between each two fastening gaps respectively;

[0031] changing the weight of the weighted components of the first experimental device and the weighted components of the second experimental device by a growth variable a for multiple times;

[0032] changing the growth variable a and repeating the above steps.

[0033] In some embodiments of the second aspect, an adhesive is provided on the stripped segments of the armored fiber and the segments of the non-armored fiber corresponding to the fastening gap.

[0034] In some embodiments of the second aspect, the adhesive is epoxy resin.

[0035] In some embodiments of the second aspect, after the epoxy resin is applied, it is left to stand for at least 24 hours to allow the epoxy resin to solidify before connecting the first and second fasteners.

[0036] Thirdly, the present invention provides a method for obtaining strain compensation coefficients, implemented based on the operation method of the experimental apparatus for obtaining strain compensation coefficients as described in the second aspect, comprising the following steps:

[0037] Acquire monitoring data from the monitors in the first and second experimental devices;

[0038] The difference between two adjacent monitoring values ​​of the monitor in the first experimental device is used as the independent variable, and the difference between two adjacent monitoring values ​​of the monitor in the second experimental device is used as the dependent variable. A straight line equation is fitted and the slope value is extracted.

[0039] Calculate the linear regression correlation index based on the linear equation;

[0040] Repeat the above steps with the growth variable 'a' changed;

[0041] Extract the linear regression correlation index closest to 1 and use its corresponding slope value as the strain compensation coefficient.

[0042] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0043] This invention provides an experimental apparatus for obtaining strain compensation coefficients, its operation, and a method for obtaining the coefficients. Through the arrangement of a first fastening component, a second fastening component, and a fixing component, the armored portion and the optical fiber portion of the stripped armored optical fiber can be independently and stably fixed. The armored portion and the optical fiber portion will not slide relative to each other during the experiment, ensuring the accuracy of the experimental measurement results. Furthermore, this allows for more accurate input parameters in obtaining the strain compensation coefficients, ultimately guaranteeing the accuracy and reliability of the obtained strain compensation coefficients, thus making the measurement results more reliable when directly measuring the strain of the armored optical fiber. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 A schematic diagram of the experimental apparatus for obtaining strain compensation coefficients provided in an embodiment of the present invention during an experiment;

[0046] Figure 2 This is a schematic diagram of the structure of the first fastening component provided in an embodiment of the present invention;

[0047] Figure 3 This is a schematic diagram of the connection structure between the first fastening member and the second fastening member provided in an embodiment of the present invention;

[0048] Figure 4 This is a schematic diagram of the reinforcement structure provided in an embodiment of the present invention;

[0049] Figure 5 This is a schematic diagram of the connection structure between the reinforcement component and the first and second fastening components provided in an embodiment of the present invention.

[0050] The attached diagram shows the markings and corresponding component names:

[0051] 1-Monitor, 2-Fiber optic patch cord, 3-First fastener, 31-First threaded hole, 32-Second threaded hole, 4-Second fastener, 41-Arc-shaped groove, 42-First through hole, 43-Third threaded hole, 44-First bolt, 5-Reinforcement, 51-Allowing hole, 52-Second bolt, 53-Small hole, 54-Second through hole, 6-Armored fiber optic cable, 61-Steel strand, 8-Cable body, 9-Weight pan, 10-Weight. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0053] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0054] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0055] In the description of this invention, the terms "front," "rear," "left," "right," "up," "down," "vertical," "horizontal," "high," "low," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0056] Firstly, such as Figures 1-5 As shown, this embodiment of the invention provides an experimental apparatus for obtaining the strain compensation coefficient. The apparatus includes a monitor 1, a first fastening member 3, a second fastening member 4, a reinforcement member 5, and a weighting component. The monitor 1 is used to obtain the Brillouin frequency shift of the optical fiber. The first fastening member 3 is provided with at least two spaced-apart first connecting portions. The second fastening member 4 is connected to the first connecting portions to form a fastening gap with the first fastening member 3 for pressing the stripped portion of the optical fiber on the armored optical fiber 6. A plurality of reinforcement members 5 are respectively connected to the second fastening member 4 one-to-one, and each reinforcement member 5 is connected to the first fastening member 3. The reinforcement member 5 is also provided with a second connecting portion for connecting to the stripped armored portion on the armored optical fiber 6. The weighting component is used to provide different gravity by connecting the optical fiber between two adjacent fastening gaps when the optical fiber is pressed by the second fastening member 4.

[0057] In this embodiment, the monitor 1 can use a BOTDA photonics instrument to monitor the Brillouin frequency shift of light. The first fastening member 3 can be configured as a long rectangular shape, and multiple first threaded holes 31 are provided on the first side of the first fastening member 3. Among them, every six threaded holes form a group of connecting holes as a first connecting part, and the multiple groups of connecting holes are arranged at equal intervals along the length direction of the first fastening member 3. In a group of connecting holes, every three connecting holes are arranged at equal intervals along the width direction of the first fastening member 3 to form a group of connecting sub-holes, and the two groups of connecting sub-holes are arranged at intervals along the length direction of the first fastening member 3.

[0058] The second fastening member 4 can be configured as a cuboid shape, wherein the length of the second fastening member 4 is equal to the width of the first fastening member 3 so that the two sides of the second fastening member 4 are flush with the two second sides of the first fastening member 3 adjacent to the first side. The second fastening member 4 is provided with a plurality of first through holes 42, the size, number and position of which correspond to a set of connecting holes on the first fastening member 3. The second fastening member 4 can be fixedly connected to the first fastening member 3 by a first bolt 44. The size of the fastening gap formed between the first fastening member 3 and the second fastening member 4 is adjusted by the first bolt 44.

[0059] A plurality of second threaded holes 32 may be provided on the second side of the first fastening member 3, and a plurality of third threaded holes 43 may be provided on the side of the second fastening member 4 that is flush with the first side. The reinforcement member 5 is provided with second through holes 54 whose position, number and size correspond to the second threaded holes 32 and third threaded holes 43 on the first fastening member 3 and the second fastening member 4. The reinforcement member 5 can be fixedly connected to the first fastening member 3 and the second fastening member 4 respectively by the second bolt 52. The specific shape of the reinforcement member 5 is not limited, as long as it can be connected to the modification material of the armored optical fiber 6. Preferably, the reinforcement member 5 has at least one connecting plane, which is used to abut against the second side of the first fastening member 3. That is, after the reinforcement member 5 is completely fixed by the second bolt 52, it can form a large contact area with the first fastening member 3 and the second fastening member 4 at the same time. In this way, even if the second bolt 52 on the first fastening member 3 or the second fastening member 4 becomes loose, the reinforcement member 5 can still have sufficient stability relative to the first fastening member 3 and the second fastening member 4, thereby ensuring that the armored part is relatively fixed to the first fastening member 3 or the second fastening member 4.

[0060] In some embodiments, the overall shape of the reinforcement 5 can be set as a regular hexagonal prism. When the reinforcement 5 is fixed to the first fastener 3 or the second fastener 4 by the second bolt 52, the axis of the reinforcement 5 is parallel to the normal direction of the arrangement center line of the two sets of connecting sub-holes on the first side. A clearance hole 51 is opened along the axis of the reinforcement 5, and the size of the clearance hole 51 is adapted to the optical fiber part. The armoring material of the armored optical fiber 6 is usually steel pipe, steel strand 61, steel tape, or aluminum tape. For the armoring material of the steel strand 61, a number of small holes 53 arranged in a circle can be provided on the reinforcement 5. The diameter of the small holes 53 is equivalent to the diameter of the steel strand 61 so that the steel strand 61 can pass through the small holes 53. The center of the arrangement of the small holes 53 is located on the axis of the clearance hole 51 of the reinforcement 5. After the armoring material is peeled off, the steel strand 61 can be passed through the small holes 53 respectively, and then the steel strand 61 and the reinforcement 5 are fixedly connected by bonding and / or welding. For example, in some embodiments, the end of the small hole 53 can be chamfered as a welding part to facilitate welding of the steel strand 61 to the reinforcement 5. In this embodiment, since the small holes 53 are arranged circumferentially, when the steel strand 61 passes through the small holes 53 and the light portion passes through the clearance hole 51, the relative position of the unstripped armor portion and the unstripped optical fiber portion can be fixed. Specifically, the optical fiber portion at the stripping opening is coaxial with the armor portion at the stripping opening, which can minimize the influence of the stripped armor material on the relative position of the armor portion and the optical fiber portion in the armored optical fiber 6. At the same time, by separately fixing the armor material of the armored optical fiber 6 with the reinforcement 5, the relative slippage between the armor portion and the optical fiber portion can be avoided when the armored optical fiber 6 is under force, thereby ensuring the accuracy of the monitoring results.

[0061] It should be noted that, in this embodiment, the center line of the arrangement refers to the fact that in a set of connecting holes, every three connecting holes have a specific arrangement direction, and there are two parallel arrangement directions in a set of connecting holes. The center line of the arrangement is the center line between the two arrangement directions.

[0062] The specific structure of the weighting component is not critical, as long as its own weight is variable and it can be connected to either the armored fiber optic cable 6 or the unarmored fiber optic cable. For ease of implementation, the weighting component may include a weight 10, a weight pan 9 for holding the weight 10, and a cable body 8; wherein the cable body 8 is connected to the weight pan 9 and is also connected to the armored fiber optic cable 6. In use, a hook can be provided at the end of the cable body 8 to hang the weighting component on the armored fiber optic cable 6. This is not only convenient to implement, but also allows the hook to slide on the armored fiber optic cable 6 under its own weight, so that the weighting component is located in the middle of the armored fiber optic cable 6, ensuring that the armored fiber optic cable 6 is subjected to relatively balanced forces.

[0063] In some embodiments, the first fastening member 3 and / or the second fastening member 4 are provided with an arc-shaped groove 41 adapted to the optical fiber portion. The arc-shaped groove 41 can minimize the deformation of the optical fiber portion while securing the armored optical fiber 6.

[0064] Based on the experimental apparatus for obtaining strain compensation coefficients provided in the above embodiments, a second aspect of the present invention provides an operating method for the experimental apparatus for obtaining strain compensation coefficients, the operating method comprising the following steps:

[0065] S1. Construct the first and second experimental setups.

[0066] Two experimental setups for obtaining strain compensation coefficients are prepared. The first setup is used to monitor the armored fiber 6, and the second setup is used to monitor the unarmored fiber. The installation environment of the first and second setups is exactly the same. For example, the first fastening component 3 and the second fastening component 4 of both setups are installed in the same orientation, and the BOTDA optical nanometer main unit of both setups is connected to the same power supply.

[0067] S2. Strip the armored optical fiber 6 to form several stripped segments.

[0068] Specifically, the number of stripped segments can be equal to the number of second fasteners 4, and the length of the stripped segments can be determined according to the width of the first fastener 3, that is, the stripping length of the stripped segments can be greater than or equal to the width of the first fastener 3. After the armored optical fiber 6 is stripped, the armored part does not detach from the armored optical fiber 6 to connect to the reinforcement 5.

[0069] S3. Twist the armored optical fiber 6 into a serpentine shape and make each stripped segment correspond to the position of the first connector.

[0070] That is, every two adjacent first connecting parts isolate the armored optical fiber 6 into a U-shaped segment, and the two adjacent U-shaped segments are located on both sides of the length direction of the first fastening member 3.

[0071] S4. Connect all the second fasteners 4 in the first experimental device to the first fasteners 3 so that each peeling segment is located in the fastening gap.

[0072] Specifically, the first fastening member 3 and the second fastening member 4 can be relatively fixed by the first bolt 44. The fastening gap between the first fastening member 3 and the second fastening member 4 can be adjusted by the number of rotations and direction of the first bolt 44. Generally, the fastening gap should be sufficient to clamp the peeling section between the first fastening member 3 and the second fastening member 4 while minimizing the deformation of the peeling section. If the first fastening member 3 and the second fastening member 4 have arc-shaped grooves, the peeling section can be placed in the arc-shaped grooves before tightening the first bolt 44.

[0073] In some embodiments, to further reduce the impact of the fastening gap on the deformation of the peeling section while ensuring its relative stability, an adhesive, such as epoxy resin, can be pre-placed in the arc-shaped groove before tightening the first bolt 44. After the epoxy resin has been allowed to stand for at least 24 hours to stabilize the relative postures of the first fastening member 3, the second fastening member 4, and the peeling section, the first bolt 44 is then tightened. In this way, the use of epoxy resin reduces the clamping force required by the first fastening member 3 and the second fastening member 4 on the peeling section, allowing the fastening gap to be appropriately adjusted to be wider, thereby reducing the deformation of the peeling section caused by clamping.

[0074] S5. Connect the armored portion stripped from the armored optical fiber 6 to the reinforcement 5 of the first experimental device and connect the reinforcement 5 to the corresponding first fastener 3 and second fastener 4.

[0075] Taking steel strand 61 as the armor material as an example: After the stripped section of the armored optical fiber 6 is fastened in the fastening gap, the reinforcing members 5 are respectively fitted from both ends of the armored optical fiber 6 so that the through holes on the reinforcing members 5 correspond to the threaded holes on the first fastening member 3 and the second fastening member 4. At the same time, the stripped steel strand 61 is passed through the small holes 53 on the reinforcing members 5 one by one. Then, the reinforcing members 5 are fastened to the first fastening member 3 and the second fastening member 4 by the second bolt 52. Each steel strand 61 can be welded and / or bonded to the reinforcing members 5 to fix the steel strand 61 to the reinforcing members 5. It should be ensured that the length of all steel strand 61 passing through the small holes 53 is consistent.

[0076] When using adhesive to fix the steel strand 61 and the reinforcement 5, adhesive can be pre-placed in the small hole 53; when using welding to fix the steel strand 61 and the reinforcement 5, a chamfer can be set at one end of the small hole 53 to facilitate welding. Of course, the end of the steel strand 61 can also be directly welded to the fixing part.

[0077] S6. Connect both ends of the armored optical fiber 6 to the monitor 1 of the first experimental device and connect multiple weighting components to the armored optical fiber 6 segments between every two interlocking gaps.

[0078] The cable 8 is then attached to the armored optical fiber segment 6 using hooks. The weighting components preferably consist of weights 10 and a weight pan 9 for ease of implementation. The armored optical fiber 6 and the monitor 1 can be connected via an optical fiber patch cord 2.

[0079] S7. Twist the unarmored fiber into the same serpentine shape as the armored fiber 6.

[0080] S8. Connect all the second fasteners 4 in the second experimental device to the first fasteners 3 so that multiple segments of the unarmored optical fiber are located in the fastening gap.

[0081] In practice, the physical properties of the armored fiber 6 are exactly the same as those of the unarmored fiber, and the length, position, and clamping force of the clamped section of the unarmored fiber are the same as those of the stripped section of the armored fiber 6 to ensure the reliability of the experimental results.

[0082] S9. Connect the reinforcement part 5 of the second experimental device to the corresponding first fastening part 3 and second fastening part 4.

[0083] S10. Connect both ends of the unarmored optical fiber to the monitor 1 of the second experimental device and connect multiple weighting components to the unarmored optical fiber segment between every two interlocking gaps.

[0084] S11. The weights of the weighting components of the first and second experimental devices are changed multiple times using the growth variable a.

[0085] Specifically, the initial state of the weighting components of the first and second experimental devices is their own weight. First type of weights 10 with a weight of a are added one by one to the weight pan 9 of the weighting components. Each time a weight 10 is added, the monitoring value of the monitor 1 in the first and second experimental devices is recorded.

[0086] S12. Change the growth variable a and repeat the above steps.

[0087] Once the total weight of the first type of weights 10 in the weighting assembly reaches the expected value, all the first type of weights 10 are removed. Then, the second type of weights 10 with a weight of b are added one by one to the weight pan 9 of the weighting assembly. The monitoring values ​​of monitor 1 in the first and second experimental devices are recorded after each addition of weights 10. The growth variable is then changed, and experiments are conducted for third, fourth, fifth, and so on weights of different types of weights 10, with the monitoring values ​​recorded in monitor 1 for each.

[0088] It is understandable that if the number of weights 10 added each time is controlled to be n, then for each type of weight 10, the monitoring value of monitor 1 in the first and second experimental devices will be n.

[0089] Based on the operation method of the above embodiments, a third aspect of the present invention provides a method for obtaining strain compensation coefficients, which includes the following steps:

[0090] Acquire monitoring data from the monitors in the first and second experimental setups.

[0091] In the first experimental setup, the monitoring data of monitor 1 is the Brillouin frequency shift value of the armored optical fiber 6. If the expected number of weights 10 in the weight pan 9 is n, then the initial value of the monitoring value of monitor 1 in the first experimental setup can be recorded as v(ε0), and the value after adding weights 10 can be recorded as v(ε0). i ), where i = 1, 2, 3...n.

[0092] In the second experimental setup, the monitoring data of monitor 1 is the Brillouin frequency shift value of the unarmored optical fiber. If the expected number of weights 10 in the weight pan 9 is n, then the initial value of the monitoring value of monitor 1 in the second experimental setup can be recorded as v'(ε0), and the value after adding weights 10 can be recorded as v'(ε0). i ), where i = 1, 2, 3...n.

[0093] The difference between two adjacent monitoring values ​​of monitor 1 in the first experimental device is used as the independent variable, and the difference between two adjacent monitoring values ​​of monitor 1 in the second experimental device is used as the dependent variable. A straight line equation is fitted and the slope value is extracted.

[0094] That is, the independent variables are v(ε1)-v(ε0), v(ε2)-v(ε1)…v(ε) n )-v(ε n-1 The point set consisting of v′(ε1)-v′(ε0), v′(ε2)-v′(ε1)…v′(ε0); the dependent variable is the set of points consisting of v′(ε1)-v′(ε0), v′(ε2)-v′(ε1)…v′(ε0). n )-v′(ε n-1 The set of points is formed by the independent and dependent variables. A scatter plot is drawn based on the point values ​​of the independent and dependent variables, and the equation of the straight line y = k1x + b1 is obtained by fitting a straight line using the least squares method.

[0095] The linear regression correlation index is calculated based on the linear equation.

[0096] The following methods can be used for calculation:

[0097]

[0098] In the formula: y i =ν′(ε i )-ν′(ε i-1 ),

[0099]

[0100] Where i = 1, 2, ..., n.

[0101] Repeat the above steps with the growth variable 'a' changed.

[0102] That is, based on y = k2x + b2, y = k3x + b3, ..., y = k N x+b N Calculate the linear regression correlation index. Where k... N This represents the slope value of the straight line obtained by experimental monitoring and calculation for the Nth type of weight 10.

[0103] Extract the linear regression correlation index closest to 1 and use its corresponding slope value as the strain compensation coefficient.

[0104] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An operation method of an experimental apparatus for obtaining strain compensation coefficients, based on an experimental apparatus for obtaining strain compensation coefficients, the experimental apparatus for obtaining strain compensation coefficients includes a monitor (1), a first fastening member (3), a second fastening member (4), a reinforcement member (5), and a weighting component. The monitor (1) is used to obtain the Brillouin frequency shift of the optical fiber; the first fastening member (3) is provided with at least two spaced first connecting parts; the second fastening member (4) is connected to the first connecting parts to form a fastening gap with the first fastening member (3) for pressing the stripped optical fiber portion on the armored optical fiber (6); multiple reinforcement members (5) are respectively connected to the second fastening member (4) one-to-one, each reinforcement member (5) is connected to the first fastening member (3), and the reinforcement member (5) is also provided with a second connecting part for connecting to the stripped armored portion on the armored optical fiber (6); the weighting component is used to provide different gravity by connecting the optical fiber between two adjacent fastening gaps when the optical fiber is pressed by the second fastening member (4), characterized in that, Includes the following steps: Two experimental setups for obtaining strain compensation coefficients were constructed, namely the first experimental setup and the second experimental setup. The armored optical fiber (6) is stripped to form several stripped segments; Twist the armored optical fiber (6) into a serpentine shape and make each stripped segment correspond to the position of the first connector; Connect all the second fasteners (4) in the first experimental device to the first fasteners (3) so that each peeling segment is located in the fastening gap; Connect the armored portion stripped from the armored optical fiber (6) to the reinforcement part (5) of the first experimental device and connect the reinforcement part (5) to the corresponding first fastener (3) and second fastener (4); Connect both ends of the armored optical fiber (6) to the monitor (1) of the first experimental device and connect multiple weighting components to the armored optical fiber (6) segment between every two interlocking gaps; The unarmored optical fiber is twisted into the same serpentine shape as the armored optical fiber (6); Connect all the second fasteners (4) in the second experimental device to the first fasteners (3) so that multiple segments of the unarmored optical fiber are located in the fastening gap; Connect the reinforcement part (5) of the second experimental device to the corresponding first fastener (3) and second fastener (4); Connect both ends of the unarmored optical fiber to the monitor (1) of the second experimental device and connect multiple weighting components to the unarmored optical fiber segment between each two interlocking gaps; The weights of the weighting components of the first and second experimental devices were changed multiple times using the growth variable 'a'. Change the growth variable 'a' and repeat the above steps.

2. The operating method of the experimental apparatus for obtaining strain compensation coefficients according to claim 1, characterized in that, The first fastener (3) and / or the second fastener (4) are provided with an arc-shaped groove (41) adapted to the optical fiber portion.

3. The operating method of the experimental apparatus for obtaining strain compensation coefficients according to claim 1, characterized in that, The reinforcement member (5) is provided with a clearance hole (51) for optical fiber to pass through and a number of fixing holes (53) evenly distributed around the clearance hole (51). The fixing holes (53) are used to pass through the steel strand (61) stripped from the armored optical fiber (6).

4. The operating method of the experimental apparatus for obtaining the strain compensation coefficient according to claim 3, characterized in that, The reinforcement member (5) is provided with a welding part for welding the steel strand (61).

5. The operating method of the experimental apparatus for obtaining the strain compensation coefficient according to claim 1, characterized in that, The weighting component includes: Weights (10); Weight pan (9) for placing weights (10); The cable body (8) is connected to the weight pan (9) and used to connect to the armored optical fiber (6).

6. The operating method of the experimental apparatus for obtaining strain compensation coefficients according to claim 1, characterized in that, Adhesive is applied to the stripped section of the armored optical fiber (6) and to the section of the unarmored optical fiber corresponding to the snap-fit ​​gap.

7. The operating method of the experimental apparatus for obtaining strain compensation coefficients according to claim 6, characterized in that, The adhesive is epoxy resin.

8. The operating method of the experimental apparatus for obtaining strain compensation coefficients according to claim 6, characterized in that, After the epoxy resin is applied, it should be left to stand for at least 24 hours to allow the epoxy resin to solidify before connecting the first fastener (3) and the second fastener (4).

9. A method for obtaining strain compensation coefficients, implemented based on the operation method of the experimental apparatus for obtaining strain compensation coefficients as described in claim 1, characterized in that, Includes the following steps: Acquire monitoring data from the monitor (1) in the first and second experimental devices; The difference between two consecutive monitoring values ​​of the monitor (1) in the first experimental device is taken as the independent variable, and the difference between two consecutive monitoring values ​​of the monitor (1) in the second experimental device is taken as the dependent variable. The straight line equation is fitted and the slope value is extracted. Calculate the linear regression correlation index based on the linear equation; Repeat the above steps with the growth variable 'a' changed; Extract the linear regression correlation index closest to 1 and use its corresponding slope value as the strain compensation coefficient.

Images