Atmospheric environmental corrosive monitoring fiber grating sensor and corrosive evaluation method

Abstract

The present application relates to the technical field of corrosion sensing, and specifically discloses an atmospheric environment corrosion monitoring fiber grating sensor and a corrosion evaluation method, which comprises a base, a first corrosion sensing unit, a second corrosion sensing unit, a third corrosion sensing unit, a fourth corrosion sensing unit, a temperature compensation unit, a first corrosion receptor, a second corrosion receptor, a third corrosion receptor and a fourth corrosion receptor. The first corrosion sensing unit, the second corrosion sensing unit, the third corrosion sensing unit and the fourth corrosion sensing unit are respectively embedded in the corresponding circular holes, and the temperature compensation unit is embedded in the base. The test carrier used by the corrosion receptor can accelerate the test process, shorten the time of atmospheric corrosion evaluation, and obtain more accurate test data in real time in situ by the Bragg grating. By establishing a corresponding relationship map between the wavelength change caused by the swelling of the corrosion receptor and the atmospheric corrosion grade, the corrosion severity of different regions of the atmospheric environment can be evaluated.

Description

Technical Field

[0001] This invention relates to the field of corrosion sensing technology, and in particular to a fiber optic grating sensor for monitoring atmospheric environmental corrosion and a method for assessing corrosion. Background Technology

[0002] Atmospheric corrosion is a widespread and common corrosion phenomenon. Assessing and classifying the severity of atmospheric corrosion in different regions and of different types can effectively guide the selection, design, maintenance, and upkeep of facilities and equipment in those regions.

[0003] In 1992, the International Organization for Standardization (ISO) issued the atmospheric corrosion classification standard ISO 9223. This standard is a widely used international standard for atmospheric corrosion assessment. It provides a method for classifying atmospheric corrosion based on the corrosion rate of standard metal specimens, as well as the combined wetting time and the content of corrosive media in the atmosphere. According to the corrosion rate of the standard metal in the first year, atmospheric corrosion is divided into six categories: C1 (very low), C2 (low), C3 (medium), C4 (high), C5 (very high), and CX (extreme).

[0004] However, with existing technologies, it is difficult to identify and subdivide the corrosion levels of some special areas according to the ISO 9223 atmospheric corrosivity classification method, and it is time-consuming, requiring a year or even longer to reach a conclusion. Summary of the Invention

[0005] The purpose of this invention is to provide a fiber optic grating sensor for monitoring atmospheric environmental corrosivity and a method for assessing corrosivity. This invention aims to solve the technical problems of existing technologies, such as the difficulty in identifying and subdividing the corrosivity levels of some special areas using the ISO 9223 atmospheric corrosivity classification and grading method, and the long time required to reach a conclusion, sometimes taking a year or even longer.

[0006] To achieve the above objectives, the present invention employs a fiber optic grating sensor for monitoring atmospheric environmental corrosion, comprising a base, a first corrosion sensing unit, a second corrosion sensing unit, a third corrosion sensing unit, a fourth corrosion sensing unit, a temperature compensation unit, a first corrosion acceptor, a second corrosion acceptor, a third corrosion acceptor, and a fourth corrosion acceptor. The base has four circular holes, which are evenly distributed on one side of the base. Each circular hole has multiple small circular holes at its bottom, arranged in a circumferential array. The first, second, third, and fourth corrosion sensing units are respectively embedded inside the corresponding circular holes. The first corrosion acceptor is disposed inside the first corrosion sensing unit, the second corrosion acceptor is disposed inside the second corrosion sensing unit, the third corrosion acceptor is disposed inside the third corrosion sensing unit, and the fourth corrosion acceptor is disposed inside the fourth corrosion sensing unit. The temperature compensation unit is embedded inside the base and is located at the center of the base.

[0007] The first corrosion sensing unit, the second corrosion sensing unit, the third corrosion sensing unit, and the fourth corrosion sensing unit have the same structure.

[0008] The first corrosion sensing unit includes a cylindrical shell, a filter membrane, a rigid corrosion conduit, a corrosion Bragg grating, a first piston, a spring, a second piston, a cap, and a corrosion fiber connector. The filter membrane is disposed inside the circular hole, the cylindrical shell is embedded inside the circular hole, one end of the rigid corrosion conduit penetrates the base and is located inside the base, the corrosion Bragg grating penetrates the rigid corrosion conduit and is located inside the rigid corrosion conduit, the first piston is disposed inside the cylindrical shell and is sleeved on the outer wall of the rigid corrosion conduit, the second piston is disposed at one end of the rigid corrosion conduit, the spring is sleeved on the outer wall of the rigid corrosion conduit and is located between the first piston and the second piston, the cap is disposed at one end of the cylindrical shell and the cap covers the cylindrical shell, and one end of the corrosion fiber connector penetrates the cap and communicates with the corrosion Bragg grating.

[0009] The first corrosion acceptor, the second corrosion acceptor, the third corrosion acceptor, and the fourth corrosion acceptor are respectively made of four different types of metals, metal compound particles, and mixtures thereof with non-metal particles.

[0010] The temperature compensation unit includes a temperature rigid conduit, a temperature Bragg grating, and a temperature fiber optic connector. The temperature rigid conduit is embedded inside the base, the temperature Bragg grating is disposed inside the temperature rigid conduit, and the temperature fiber optic connector is disposed at one end of the temperature rigid conduit and is connected to the temperature Bragg grating.

[0011] This invention also provides a method for assessing the corrosivity of a fiber Bragg grating sensor for monitoring atmospheric corrosion, applied to the fiber Bragg grating sensor for monitoring atmospheric corrosion as described above, comprising the following steps:

[0012] When the corrosion reaction occurs, the corrosion acceptor expands due to corrosion, squeezing the first piston to move to the right;

[0013] This, in turn, pushes the spring to transmit the expansion stress to the second piston, which in turn pulls the fiber grating, causing a change in the center wavelength;

[0014] The change in center wavelength reflects the change in volume caused by corrosion expansion; that is, the greater the change in volume caused by corrosion expansion, the greater the change in center wavelength.

[0015] Ten typical locations with an atmospheric environmental corrosivity level of C1 (very low) were selected according to ISO 9223. The same fiber optic grating sensor for atmospheric environmental corrosivity monitoring was deployed at these ten typical locations, and the changes in the center wavelength were recorded over a certain period of time. The values ​​were α1, α2, α3, α4, α5, α6, α7, α8, α9 and α10, and the maximum value was taken as the interval reference maximum value α.

[0016] The atmospheric corrosivity in the range of center wavelength variation (0, α) is defined as C1;

[0017] Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C2 (low) at the same time is taken as the reference maximum value β for this interval.

[0018] The atmospheric corrosivity in the range of center wavelength variation (α, β) is defined as C2;

[0019] Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C3 (medium) at the same time is taken as the reference maximum value γ for this interval.

[0020] The atmospheric corrosivity of the center wavelength variation range in (β, γ) is defined as C3;

[0021] Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C4 (high) at the same time is taken as the reference maximum value δ for this interval.

[0022] The atmospheric corrosivity in the range of center wavelength variation (γ, δ) is defined as C4;

[0023] Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C5 (very high) at the same time is taken as the reference maximum value ε for this interval.

[0024] The atmospheric corrosivity in the range of center wavelength variation (δ, ε) is defined as C5;

[0025] Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of CX (extreme) at the same time is taken as the reference maximum value ζ for this interval.

[0026] The atmospheric corrosivity in the range of center wavelength variation (ε, ζ) is defined as CX;

[0027] This method establishes a correlation between the changes in the center wavelength of the Bragg grating caused by the expansion of various corrosion receptors at different times and the atmospheric corrosion level, enabling the assessment of the severity of atmospheric corrosion in different regions and for different types of environments.

[0028] The beneficial effects of the fiber Bragg grating sensor for atmospheric environmental corrosion monitoring and the corrosion assessment method of the present invention are as follows: The present invention utilizes the expansion of different first, second, third, and fourth corrosion receptors due to atmospheric corrosion. This expansion compresses the first piston, causing a change in the center wavelength of the corrosion Bragg grating. The amount of wavelength change allows for the measurement of atmospheric environmental corrosion. In-situ online monitoring of the corrosion receptors is possible, enabling the acquisition of more accurate experimental data in real time. The experimental carrier used for the corrosion receptors can accelerate the experimental process and shorten the time for atmospheric corrosion assessment. By establishing a correlation graph between the wavelength change caused by the expansion of the corrosion receptors and the atmospheric corrosion level, the severity of atmospheric environmental corrosion in different regions can be assessed. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of the fiber optic grating sensor for monitoring atmospheric environmental corrosion according to the present invention.

[0031] Figure 2 This is a bottom view of the fiber optic grating sensor for monitoring atmospheric environmental corrosion according to the present invention.

[0032] Figure 3 This is the invention Figure 2 A cross-sectional view of the AA line structure.

[0033] Figure 4 This is the invention Figure 2 BB line structural cross-sectional view.

[0034] Figure 5 This is a flowchart of the steps of the corrosion assessment method for the fiber optic grating sensor for atmospheric environmental corrosion monitoring of the present invention.

[0035] 1-Base, 2-First corrosion sensing unit, 3-Second corrosion sensing unit, 4-Third corrosion sensing unit, 5-Fourth corrosion sensing unit, 6-Temperature compensation unit, 7-First corrosion acceptor, 8-Second corrosion acceptor, 9-Third corrosion acceptor, 10-Fourth corrosion acceptor, 11-Shell, 12-Filter membrane, 13-Corrosion rigid conduit, 14-Corrosion Bragg grating, 15-First piston, 16-Spring, 17-Second piston, 18-Cap, 19-Corrosion fiber optic connector, 20-Temperature rigid conduit, 21-Temperature Bragg grating, 22-Temperature fiber optic connector, 23-Circular hole, 24-Small round hole. Detailed Implementation

[0036] Please see Figures 1 to 4This invention provides a fiber optic grating sensor for monitoring atmospheric corrosion, comprising a base 1, a first corrosion sensing unit 2, a second corrosion sensing unit 3, a third corrosion sensing unit 4, a fourth corrosion sensing unit 5, a temperature compensation unit 6, a first corrosion acceptor 7, a second corrosion acceptor 8, a third corrosion acceptor 9, and a fourth corrosion acceptor 10. The base 1 has four circular holes 23, which are evenly distributed on one side of the base 1. Each circular hole 23 has multiple small circular holes 24 at its bottom, arranged in a circumferential array. The first corrosion sensing unit 2... The second corrosion sensing unit 3, the third corrosion sensing unit 4, and the fourth corrosion sensing unit 5 are respectively embedded inside the corresponding circular holes 23. The first corrosion receptor 7 is disposed inside the first corrosion sensing unit 2, the second corrosion receptor 8 is disposed inside the second corrosion sensing unit 3, the third corrosion receptor 9 is disposed inside the third corrosion sensing unit 4, the fourth corrosion receptor 10 is disposed inside the fourth corrosion sensing unit 5, and the temperature compensation unit 6 is embedded inside the base 1, and the temperature compensation unit 6 is located at the center of the base 1.

[0037] Furthermore, the first corrosion sensing unit 2, the second corrosion sensing unit 3, the third corrosion sensing unit 4, and the fourth corrosion sensing unit 5 have the same structure.

[0038] Further, the first corrosion sensing unit 2 includes a cylindrical shell 11, a filter membrane 12, a rigid corrosion conduit 13, a corrosion Bragg grating 14, a first piston 15, a spring 16, a second piston 17, a cap 18, and a corrosion fiber optic connector 19. The filter membrane 12 is disposed at the bottom of the circular hole 23, the cylindrical shell 11 is embedded inside the circular hole 23, one end of the rigid corrosion conduit 13 penetrates the base 1 and is located inside the base 1, and the corrosion Bragg grating 14 penetrates the rigid corrosion conduit 13 and is located inside the rigid corrosion conduit 13. The first piston 15 is disposed inside the cylindrical shell 11 and is sleeved on the outer wall of the corroded rigid conduit 13. The second piston 17 is disposed at one end of the corroded rigid conduit 13. The spring 16 is sleeved on the outer wall of the corroded rigid conduit 13 and is located between the first piston 15 and the second piston 17. The cap 18 is disposed at one end of the cylindrical shell 11 and covers the cylindrical shell 11. One end of the corroded optical fiber connector 19 passes through the cap 18 and communicates with the corroded Bragg grating 14.

[0039] Furthermore, the first corrosion acceptor 7, the second corrosion acceptor 8, the third corrosion acceptor 9, and the fourth corrosion acceptor 10 are respectively composed of four different types of metals, metal compound particles, and mixtures thereof with non-metal particles.

[0040] Furthermore, the temperature compensation unit 6 includes a temperature rigid conduit 20, a temperature Bragg grating 21, and a temperature fiber optic connector 22. The temperature rigid conduit 20 is embedded inside the base 1, the temperature Bragg grating 21 is disposed inside the temperature rigid conduit 20, and the temperature fiber optic connector 22 is disposed at one end of the temperature rigid conduit 20 and is connected to the temperature Bragg grating 21.

[0041] In this embodiment, the filter membrane 12 is breathable, which can prevent corrosion receptors from leaking out through the bottom of the circular hole 23. Air, water vapor and gas molecules can enter the shell 11 through the filter membrane 12 and come into contact with the corrosion receptors, and produce a corrosion reaction.

[0042] The rigid corrosion conduit 13 is sleeved on the outer wall of the rigid corrosion Bragg grating 14, and the rigid temperature conduit 20 is sleeved on the outer wall of the rigid temperature Bragg grating 21, serving as a support and protection.

[0043] The second piston 17 and the cap 18 each have a hole in the center for the optical fiber connector to penetrate and be embedded into the interior of the cylindrical shell 11 and communicate with the Bragg grating;

[0044] A spring 16 is installed between the first piston 15 and the second piston 17 to transmit stress and keep the corroded Bragg grating 14 in a stretched state.

[0045] This invention utilizes the atmospheric corrosion expansion of different corrosion receptors 7, 8, 9, and 10 to compress the first piston 15, causing a change in the center wavelength of the corrosion Bragg grating 14. The amount of wavelength change allows for the measurement of atmospheric corrosivity, enabling in-situ online monitoring of the corrosion receptors and real-time acquisition of more accurate experimental data. The experimental carrier used for the corrosion receptors accelerates the experimental process and shortens the time for atmospheric corrosivity assessment. By establishing a correlation between the wavelength change caused by the expansion of the corrosion receptors and the atmospheric corrosion level, the severity of atmospheric corrosion in different regions can be assessed.

[0046] Please see Figure 5 The present invention also provides a method for assessing the corrosivity of a fiber Bragg grating sensor for monitoring atmospheric environmental corrosivity, applicable to the fiber Bragg grating sensor for monitoring atmospheric environmental corrosivity as described above, comprising the following steps:

[0047] S1: When the corrosion reaction occurs, the corrosion acceptor expands due to corrosion, squeezing the first piston 15 to move to the right;

[0048] S2: This pushes the spring 16 to transmit the expansion stress to the second piston 17, and the second piston 17 pulls the fiber grating to cause a change in the center wavelength;

[0049] S3: The change in center wavelength reflects the volume change caused by corrosion expansion; that is, the greater the volume change caused by corrosion expansion, the greater the change in center wavelength.

[0050] S4: Based on ISO9223, select 10 typical locations with an atmospheric environmental corrosion level of C1. Deploy the same fiber optic sensor for atmospheric environmental corrosion monitoring at these 10 typical locations and record the changes in center wavelength over a certain period of time, which are α1, α2, α3, α4, α5, α6, α7, α8, α9 and α10 respectively. Take the maximum value as the interval reference maximum value α.

[0051] S5: The atmospheric corrosivity in the center wavelength variation range of (0, α) is defined as C1;

[0052] S6: Similarly, take the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C2 (low) at the same time as the reference maximum value β for this interval.

[0053] S7: The atmospheric corrosivity in the center wavelength variation range (α, β) is defined as C2;

[0054] S8: Similarly, take the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C3 (medium) at the same time as the reference maximum value γ for this interval.

[0055] S9: The atmospheric corrosivity in the center wavelength variation range (β, γ) is defined as C3;

[0056] S10: Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C4 (high) at the same time is taken as the reference maximum value δ for this interval.

[0057] S11: The atmospheric corrosivity in the center wavelength variation range (γ, δ) is defined as C4;

[0058] S12: Similarly, take the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C5 (very high) at the same time as the reference maximum value ε for this interval.

[0059] S13: The atmospheric corrosivity in the center wavelength variation range (δ, ε) is defined as C5;

[0060] S14: Similarly, take the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of CX (extreme) at the same time as the reference maximum value ζ for this interval.

[0061] S15: The atmospheric corrosivity in the center wavelength variation range (ε, ζ) is defined as CX;

[0062] S16: This method is used to establish a correlation map between the change in the center wavelength of the Bragg grating caused by the expansion of various corrosion receptors at different times and the corrosion level of the atmospheric environment, so as to assess the severity of corrosion in different types of atmospheric environments in different regions.

[0063] Application Example 1:

[0064] In this embodiment, a coastal town was selected as the deployment location for fiber optic grating sensors for atmospheric environmental corrosion monitoring. Four different types of metal particles, metal compound particles, or mixtures of metals, metal compounds, and non-metals (A, B, C, and D) were selected as corrosion acceptors. During packaging, the corrosion acceptor volumes were ensured to be uniform, and the Bragg gratings in the four corrosion sensing units were stretched in the same state. Over one year, the center wavelength of the Bragg grating in A increased by a1, the center wavelength of the Bragg grating in B increased by b1, the center wavelength of the Bragg grating in C increased by c1, and the center wavelength of the Bragg grating in D increased by d1. Based on the correlation between the change in center wavelength caused by corrosion expansion of the corrosion acceptors over one year and the atmospheric environmental corrosion level, the severity of atmospheric environmental corrosion in this region was assessed.

[0065] Application Example 2:

[0066] In this embodiment, towns A and B in the coastal area were selected as the locations for deploying fiber optic grating sensors for monitoring atmospheric environmental corrosion. Four typical metal particles or metal compound particles or mixtures of metal, metal compound, and non-metal particles A, B, C, and D were selected as corrosion receptors. During encapsulation, ensure consistent corrosion acceptor volume and consistent Bragg grating stretching in the four corrosion sensing units. Over one year, in town A, the center wavelength of the Bragg grating in A increases by a1, in town B by b1, in town C by c1, and in town D by d1; in town B, the center wavelength of the Bragg grating in A increases by a2, in town B by b2, in town C by c2, and in town D by d2. If a1>a2, then the atmospheric corrosivity of town A is greater than that of town B; if b1>b2, then the atmospheric corrosivity of town A is greater than that of town B; if c1>c2, then the atmospheric corrosivity of town A is greater than that of town B; if d1>d2, then the atmospheric corrosivity of town A is greater than that of town B. This method can be used to compare the relative strength of atmospheric corrosivity between the two regions.

Claims

1. A fiber optic grating sensor for monitoring atmospheric environmental corrosivity, characterized in that, The device includes a base, a first corrosion sensing unit, a second corrosion sensing unit, a third corrosion sensing unit, a fourth corrosion sensing unit, a temperature compensation unit, a first corrosion acceptor, a second corrosion acceptor, a third corrosion acceptor, and a fourth corrosion acceptor. The base has four circular holes, which are evenly distributed on one side of the base. Each circular hole has multiple small circular holes at its bottom, arranged in a circumferential array. The first, second, third, and fourth corrosion sensing units are respectively embedded inside their respective circular holes. The first corrosion acceptor is disposed inside the first corrosion sensing unit, the second corrosion acceptor is disposed inside the second corrosion sensing unit, the third corrosion acceptor is disposed inside the third corrosion sensing unit, and the fourth corrosion acceptor is disposed inside the fourth corrosion sensing unit. The temperature compensation unit is embedded inside the base and is located at the center of the base. The first corrosion sensing unit, the second corrosion sensing unit, the third corrosion sensing unit, and the fourth corrosion sensing unit have the same structure. The first corrosion sensing unit includes a cylindrical shell, a filter membrane, a rigid corrosion conduit, a corrosion Bragg grating, a first piston, a spring, a second piston, a cap, and a corrosion fiber connector. The filter membrane is disposed at the bottom of the circular hole. The cylindrical shell is embedded inside the circular hole. One end of the rigid corrosion conduit penetrates the base and is located inside the base. The corrosion Bragg grating penetrates the rigid corrosion conduit and is located inside the rigid corrosion conduit. The first piston is disposed inside the cylindrical shell and is sleeved on the outer wall of the rigid corrosion conduit. The second piston is disposed at one end of the rigid corrosion conduit. The spring is sleeved on the outer wall of the rigid corrosion conduit and is located between the first piston and the second piston. The cap is disposed at one end of the cylindrical shell and covers the cylindrical shell. One end of the corrosion fiber connector penetrates the cap and communicates with the corrosion Bragg grating.

2. The fiber optic grating sensor for monitoring atmospheric environmental corrosivity as described in claim 1, characterized in that, The first corrosion acceptor, the second corrosion acceptor, the third corrosion acceptor and the fourth corrosion acceptor are respectively made of four different types of metals, metal compound particles and mixtures thereof with non-metal particles.

3. The fiber optic grating sensor for monitoring atmospheric environmental corrosivity as described in claim 2, characterized in that, The temperature compensation unit includes a temperature rigid conduit, a temperature Bragg grating, and a temperature fiber optic connector. The temperature rigid conduit is embedded inside the base, the temperature Bragg grating is disposed inside the temperature rigid conduit, and the temperature fiber optic connector is disposed at one end of the temperature rigid conduit and is connected to the temperature Bragg grating.

4. A method for assessing the corrosivity of a fiber Bragg grating sensor for monitoring atmospheric environmental corrosivity, applied in the fiber Bragg grating sensor for monitoring atmospheric environmental corrosivity as described in claim 3, comprising the following steps: When the corrosion reaction occurs, the corrosion acceptor expands due to corrosion, squeezing the first piston to move to the right; This, in turn, pushes the spring to transmit the expansion stress to the second piston, which in turn pulls the fiber grating, causing a change in the center wavelength; The change in center wavelength reflects the change in volume caused by corrosion expansion; that is, the greater the change in volume caused by corrosion expansion, the greater the change in center wavelength. Ten typical locations with an atmospheric corrosion rating of C1 were selected according to ISO 9223. The same fiber optic grating sensor for atmospheric corrosion monitoring was deployed at these ten locations, and the change in center wavelength was recorded over a certain period of time. The values ​​were α1, α2, α3, α4, α5, α6, α7, α8, α9 and α10. The maximum value was taken as the interval reference maximum value α. The atmospheric corrosivity in the range of center wavelength variation (0, α) is defined as C1; Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C2 at the same time is taken as the reference maximum value β for this interval. The atmospheric corrosivity in the range of center wavelength variation (α, β) is defined as C2; Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C3 at the same time is taken as the reference maximum value γ for this interval. The atmospheric corrosivity of the center wavelength variation range in (β, γ) is defined as C3; Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C4 at the same time is taken as the reference maximum value δ for this interval. The atmospheric corrosivity in the range of center wavelength variation (γ, δ) is defined as C4; Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of C5 at the same time is taken as the reference maximum value ε for this interval. The atmospheric corrosivity in the range of center wavelength variation (δ, ε) is defined as C5; Similarly, the maximum value of the change in the center wavelength of the fiber optic grating sensor for atmospheric environmental corrosion monitoring at 10 locations with an atmospheric environmental corrosion level of CX at the same time is taken as the reference maximum value ζ for this interval. The atmospheric corrosivity in the range of center wavelength variation (ε, ζ) is defined as CX; This method establishes a correlation between the changes in the center wavelength of the Bragg grating caused by the expansion of various corrosion receptors at different times and the atmospheric corrosion level, enabling the assessment of the severity of atmospheric corrosion in different regions and for different types of environments.

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