A seamless line rail deformation online monitoring system and monitoring method

Abstract

The present invention discloses an online monitoring system and method for seamless railway rail deformation. The system includes a sensing fiber, a relay box, a fiber optic demodulator, and an industrial control computer. The sensing fiber is installed at the waist of the rail to monitor rail strain changes in real time. The relay box is installed at the bottom of the rail, connected to the sensing fiber, and marks each sensing fiber measurement section. The fiber optic demodulator is connected to the sensing fiber via a jumper to collect monitoring data from the sensing fiber. The industrial control computer is connected to the fiber optic demodulator via a data transmission line to process and analyze the monitoring data. The method includes: calibrating each sensing fiber measurement section; debugging the equipment of the seamless railway rail deformation online monitoring system; calculating the temperature change based on the acquired Brillouin frequency data, eliminating the temperature effect, calculating the actual longitudinal deformation of the rail, and identifying rail anomalies. The present invention achieves monitoring of the longitudinal deformation of the seamless railway rail by monitoring the Brillouin frequency change.

Description

Technical Field

[0001] The present invention relates to the technical field of railway track safety monitoring, and in particular to an online monitoring system and method for seamless line rail deformation. Background Art

[0002] China has become the country with the longest operating mileage and highest operating speeds of high-speed railways in the world. During the large-scale construction of high-speed railways in my country, seamless rails have been widely used on high-speed lines because they eliminate rail joints, significantly improving track structure and reducing vibration. The absence of rail joints prevents the rails from freely expanding and contracting with temperature changes, generating significant internal thermal stresses. When fastener pressure is insufficient to offset these stresses, the rails undergo longitudinal deformation, causing expansion and creep when temperatures rise, and rail breakage when temperatures drop, seriously impacting train safety. Therefore, research on online monitoring technology for seamless rail deformation can provide real-time information on longitudinal rail deformation and identify localized rail creep, which is crucial for preventing expansion and breakage and ensuring safe railway operations.

[0003] Currently, the main monitoring methods for longitudinal rail deformation in my country include manual wire-drawing methods using displacement observation piles, optical instruments, or magnetic sensors. Foreign measurement methods also largely rely on displacement observation piles and optical measurement methods. The manual wire-drawing method suffers from large measurement errors and is widely used in areas such as early conventional railways, where relatively low precision is required for longitudinal rail deformation measurement. It is unsuitable for longitudinal rail displacement monitoring on high-speed seamless railways. With the increasing maturity of fiber Bragg grating (FBG) technology, its high measurement density, fast response speed, and high accuracy have led to its widespread application in various engineering fields.

[0004] Existing fiber optic monitoring technology still faces the following shortcomings in monitoring rail deformation on high-speed railway seamless lines: the influence of temperature is not fully considered, the stress changes of rails under temperature changes are complex, and the existing methods are not accurate enough in eliminating the temperature influence; the monitoring range is limited, and the coverage of traditional fiber optic monitoring systems is small, which cannot meet the full-line monitoring needs of long-distance rails; the data analysis capabilities are insufficient, and the data processing efficiency of the existing monitoring system is low, and there is a lack of automated data analysis and anomaly identification capabilities. Summary of the Invention

[0005] The object of the present invention is to provide an online monitoring system and method for deformation of seamless line rails, which is used to solve at least one of the above-mentioned technical problems. It can monitor the longitudinal deformation of seamless rails by monitoring the change in Brillouin frequency, reduce the influence of temperature on the measurement results, and improve the monitoring accuracy.

[0006] The embodiment of the present invention is achieved as follows:

[0007] A seamless line rail deformation online monitoring system comprises a sensing optical fiber, a relay box, an optical fiber demodulator and an industrial control computer.

[0008] The sensing optical fiber is arranged at the waist of the rail and is used to monitor the strain change of the rail in real time.

[0009] The relay box is installed at the bottom of the rail, connected to the sensing optical fiber, and is used to mark each sensing optical fiber measurement section.

[0010] The optical fiber demodulator is connected to the sensing optical fiber via a jumper, and is used to transmit and receive pulse light and continuous light to the sensing optical fiber, and collect monitoring data of the sensing optical fiber.

[0011] The industrial computer is connected to the optical fiber demodulator via a data transmission line for processing and analyzing the monitoring data.

[0012] In a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring system, the sensing optical fiber includes a strain monitoring optical fiber and a temperature monitoring optical fiber.

[0013] The strain monitoring optical fiber and the temperature monitoring optical fiber are fused together at the end of a section of the sensing optical fiber measuring section.

[0014] The technical benefit is that by deploying optical fiber sensors along the rail waist, the force applied to the rail during operation can be accurately reflected. The strain and temperature monitoring fibers are fused together at the end of each measuring section, enabling simultaneous monitoring of strain and temperature.

[0015] In a preferred embodiment of the present invention, in the above-mentioned online monitoring system for deformation of seamless railway rails, the strain monitoring optical fiber is connected to the starting end of the optical fiber demodulator through the jumper.

[0016] The temperature monitoring optical fiber is connected to the end of the optical fiber demodulator through the jumper.

[0017] The technical benefit lies in fusing the strain monitoring fiber and the temperature monitoring fiber at the monitoring endpoint to form a closed optical loop, ensuring continuous transmission of the optical signal throughout the entire sensing fiber. Independently acquiring temperature data through the temperature monitoring fiber and combining it with the data from the strain monitoring fiber for comprehensive analysis effectively eliminates the impact of temperature changes on strain measurements.

[0018] In a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring system, the relay box includes a shell, an optical fiber connector, a clamp and a sealing strip.

[0019] The optical fiber connector is arranged in the housing and connected to the sensing optical fiber.

[0020] The clamp is installed on the shell and fixed at the rail bottom of the rail.

[0021] The sealing strip is arranged at the connection of the shell.

[0022] A method for online monitoring deformation of seamless railway rails, comprising:

[0023] The devices in the seamless railway rail deformation online monitoring system are connected in sequence to form a closed optical path loop. The seamless railway rail deformation online monitoring system is the system described above.

[0024] Each sensing optical fiber measurement section is calibrated, including the calibration of the starting and ending positions of the measurement area, the calibration of the measurement points within the measurement area, and the calibration of the corresponding points in the measurement area.

[0025] The equipment debugging of the seamless line rail deformation online monitoring system is carried out.

[0026] The temperature change is calculated based on the obtained Brillouin frequency data, the temperature influence is eliminated, the actual longitudinal deformation of the rail is calculated, and rail anomalies are identified.

[0027] In a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the calibration of the start and end positions of the measurement area includes:

[0028] An optical fiber demodulator is used to transmit and receive pulsed light and continuous light to the sensing optical fiber, detect the returned Brillouin scattering signal, and obtain the distribution curve of the Brillouin frequency along the length of the optical fiber under the reference state.

[0029] Temperature changes are applied to the sensing optical fibers at both end boundaries of each sensing optical fiber measuring section.

[0030] Obtain a Brillouin frequency shift curve caused by temperature change, find a peak in the shift curve, the position of the peak corresponds to the spatial position of the sensing fiber, and locate the starting point and end point of the sensing fiber measurement section.

[0031] Its technical effect is: by combining the calibration method of Brillouin frequency shift, temperature compensation technology and partition identification mechanism, the accuracy of the online monitoring system for seamless line rail deformation is improved.

[0032] In a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the calibration of the measuring points in the measuring area includes:

[0033] Continuously measure the sensing optical fiber in each sensing optical fiber measuring section to collect original data.

[0034] The raw data is filtered to remove noise and invalid data to obtain a smooth signal curve.

[0035] The smooth signal curve is analyzed to extract typical characteristic parameters.

[0036] Check whether the extracted typical characteristic parameters conform to the sine curve characteristics. If so, perform peak calculation. If not, re-collect and process the original data.

[0037] Perform peak calculation to identify the peak A in the smooth signal curve, and mark the starting position abscissa X1 and the ending position abscissa X2 of the curve, where X2>X1.

[0038] Calculate the half-peak value A / 2 of the smooth signal curve, and obtain the horizontal coordinates x1, x2, ... x of the points on the smooth signal curve where the amplitude is half-peak. i ,….

[0039] According to X1≤x i ≤X2, and filter out the effective measuring points in each sensing optical fiber measuring section.

[0040] Its technical effect is: through continuous measurement of the sensing optical fiber measurement section and collection of raw data, combined with filtering processing and curve smoothing, noise and invalid data are effectively removed, and effective measurement points are accurately extracted through the half-wave full width method, thereby improving measurement accuracy and stability.

[0041] In a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the calibration of corresponding points in the measurement area includes:

[0042] The points in the strain monitoring section and the temperature monitoring section will be matched one by one, and the geographical locations of the strain measuring points and the temperature measuring points will be the same.

[0043] A pair of measuring points within the sensing optical fiber measuring section is obtained.

[0044] Its technical effect is: by matching strain measurement points and temperature measurement points one by one, it ensures the spatial consistency of measurement data, accurately eliminates the temperature influence, and improves the monitoring accuracy, reliability and analysis efficiency of the system.

[0045] In a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the equipment debugging of the online monitoring system for deformation of seamless railway rails includes:

[0046] A longitudinal tension test simulating rail deformation is performed on the debugging optical fiber to verify the sensitivity of the debugging optical fiber in sensing strain signals and the reliability of data transmission.

[0047] Debug the stability of the light source intensity of the fiber optic interrogator.

[0048] Debug the software acquisition mode of the industrial computer.

[0049] Its technical effects are: simulating rail deformation through longitudinal tensioning tests, verifying and debugging the sensitivity of the optical fiber to strain signals, and ensuring the sensitivity and accuracy of strain signal perception; analyzing the signal transmission performance of the sensing optical fiber, ensuring that the signal can be stably transmitted to the optical fiber demodulator and industrial computer, and ensuring the stability and reliability of data transmission; ensuring the stability of the optical signal and reducing measurement errors caused by light source fluctuations by debugging the intensity of the light source; and optimizing the data acquisition process by debugging the software acquisition mode of the industrial computer, ensuring that the strain signal and temperature signal can be processed synchronously in the best way, reducing data processing delays, and improving the system's response speed and monitoring efficiency.

[0050] In a preferred embodiment of the present invention, in the above-mentioned online monitoring method for seamless railway rail deformation, the temperature change is calculated based on the acquired Brillouin frequency data, the temperature effect is eliminated, and the actual longitudinal deformation of the rail is calculated. The identification of rail abnormality includes:

[0051] Use a fiber optic interrogator to obtain Brillouin frequency data from the strain monitoring fiber and the temperature monitoring fiber.

[0052] Calculate the Brillouin frequency change Δv of the temperature monitoring optical fiber at the i-th measurement point ti =v ti -v 0i , where Δv ti is the Brillouin frequency at the measuring point, v 0i is the reference frequency of the measuring point.

[0053] Calculate the temperature change of the i-th measuring point Among them, k t is the frequency-temperature conversion coefficient of the temperature monitoring optical fiber.

[0054] Calculate the frequency change Δv caused by temperature change ∈ti =Δt i ×k ∈t , where k ∈t is the frequency-temperature conversion coefficient of the strain monitoring optical fiber.

[0055] The Brillouin frequency change v of the strain monitoring optical fiber is ∈i Eliminate the frequency change Δv caused by temperature change ∈ti As well as the reference Brillouin frequency change v0 of the rail, the Brillouin frequency change Δv caused by the actual rail deformation is calculated. ∈i =v ∈i -v0-Δv ∈ti .

[0056] Calculate the rail strain at the i-th measuring point Among them, k ∈ is the strain-frequency conversion coefficient of the strain monitoring optical fiber.

[0057] According to the relationship between strain and deformation, the actual longitudinal deformation of the rail is calculated as Δl=∈ i ×L, where L is the length of the measurement area.

[0058] The calculated actual longitudinal deformation is compared with the standard value to determine whether the actual longitudinal deformation exceeds the normal range, thereby identifying whether there is an abnormality in the rail.

[0059] The technical benefits of this approach are: by using a specialized temperature-monitoring optical fiber to obtain the temperature variation at the measuring point, and utilizing a frequency-temperature conversion coefficient to eliminate the temperature effect on the strain-monitoring optical fiber, the temperature-induced frequency variation and the reference frequency variation are removed from the Brillouin frequency variation of the strain-monitoring optical fiber, accurately obtaining the true strain frequency variation on the strain-monitoring optical fiber. This avoids misjudgments caused by ambient temperature changes and accurately calculates the Brillouin frequency variation caused by the actual rail deformation. This achieves precise separation of temperature and strain, high-precision calculation of true deformation, and rapid identification and alarm of rail anomalies.

[0060] The beneficial effects of the embodiments of the present invention are:

[0061] This invention, based on distributed fiber optic sensing and monitoring technology based on Brillouin scattering, proposes an online monitoring system and method for seamless rail deformation. When the distributed optical fiber deforms or experiences temperature changes, the Brillouin frequency of the fiber itself changes. By monitoring this change in Brillouin frequency, the longitudinal deformation of the seamless rail can be monitored. Due to the temperature-sensitive nature of optical fiber, this invention proposes a directional, real-time temperature compensation method. This allows for real-time temperature compensation at each monitoring point, thereby reducing the impact of temperature on measurement results and improving monitoring accuracy.

[0062] The present invention provides an online monitoring system and method for seamless railway rail deformation. Using seamless railway rails as the monitoring object, a rail longitudinal displacement monitoring device based on distributed fiber optic sensing technology monitors the optical fiber strain information caused by the seamless railway rail longitudinal displacement in real time. The longitudinal displacement value is then obtained through a data analysis and processing algorithm. This system can monitor the seamless railway rail deformation state, identify abnormal conditions such as localized rail creep, and locate the location of the occurrence, thereby ensuring railway line operation safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0064] Figure 1 This is a structural diagram of the online monitoring system for seamless railway rail deformation of the present invention;

[0065] Figure 2 This is a schematic diagram of the sensor optical fiber layout structure of the seamless railway rail deformation online monitoring system of the present invention;

[0066] Figure 3 This is a schematic diagram of the relay box layout structure of the seamless railway rail deformation online monitoring system of the present invention;

[0067] Figure 4 Another structural diagram of the relay box arrangement of the seamless railway rail deformation online monitoring system of the present invention;

[0068] Figure 5 This is a schematic diagram of a sensing optical fiber test in the method for online monitoring deformation of seamless railway rails of the present invention;

[0069] Figure 6 This is a schematic diagram of a calibration curve for a measurement area in the online monitoring method for seamless railway rail deformation according to the present invention;

[0070] Figure 7 Schematic diagram of the distribution of measuring points within the measuring area in the online monitoring method for seamless railway rail deformation of the present invention;

[0071] Figure 8 Schematic diagram of the curve of data acquisition change in the measurement area in the online monitoring method for seamless railway rail deformation of the present invention;

[0072] Figure 9 The figure is a schematic diagram of the calibration process of the measuring points in the measuring area in the online monitoring method for seamless railway rail deformation of the present invention.

[0073] In the figure: 1-relay box; 101-fixture; 102-fiber optic connector; 2-rail; 3-sensing fiber optic; 301-strain monitoring fiber optic; 302-temperature monitoring fiber optic; 4-fiber optic demodulator; 5-industrial computer. DETAILED DESCRIPTION

[0074] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0075] Please refer to Figures 1 to 4 The first embodiment of the present invention provides an online monitoring system for seamless railway rail deformation, which includes a sensing optical fiber, a relay box 1, a fiber optic demodulator 4 and an industrial computer 5; the sensing optical fiber is arranged at the waist of the rail 2 and is used to monitor the strain changes of the rail in real time; the relay box 1 is installed at the bottom of the rail 2 and is connected to the sensing optical fiber to mark each sensing optical fiber measurement section; the fiber optic demodulator 4 is connected to the sensing optical fiber through a jumper cable and is used to transmit and receive pulse light and continuous light to the sensing optical fiber to collect monitoring data of the sensing optical fiber; the industrial computer 5 is connected to the fiber optic demodulator 4 through a data transmission line to process and analyze the monitoring data.

[0076] like Figure 2 As shown, in a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring system, the sensing optical fiber includes a strain monitoring optical fiber 301 and a temperature monitoring optical fiber 302; the strain monitoring optical fiber 301 and the temperature monitoring optical fiber 302 are fused into one at the end of a section of the sensing optical fiber measurement section.

[0077] The technical benefit lies in the fact that by deploying optical fiber sensors along the rail waist, where stress is concentrated, the stress conditions during rail operation can be accurately reflected. The strain and temperature monitoring fibers are designed to be fused together at the end of each measuring section, enabling simultaneous monitoring of strain and temperature.

[0078] In a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring system, the strain monitoring optical fiber 301 is connected to the starting end of the optical fiber demodulator 4 through the jumper; the temperature monitoring optical fiber 302 is connected to the ending end of the optical fiber demodulator 4 through the jumper.

[0079] The structure of the sensing fiber is as follows Figure 5As shown, the solid line core is the strain monitoring optical fiber 301, and the dotted line core is the temperature monitoring optical fiber 302. In order to realize the continuous transmission of the optical signal on the strain monitoring core and the temperature monitoring core, the two optical fibers are fused at the monitoring end position. In order to conveniently obtain the correspondence between the line mileage and the optical fiber mileage, the strain monitoring part of the comprehensive monitoring optical fiber needs to be in front and the temperature monitoring part in the back. Therefore, the strain monitoring optical fiber 301 is connected to the starting end of the optical fiber demodulator 4 through an optical fiber jumper connection, and the temperature monitoring optical fiber 302 is connected to the end end of the optical fiber demodulator 4 through a jumper connection, and a closed loop of the optical path is formed between the optical fiber demodulator 4 and the sensing optical fiber. The transmission direction of the optical signal on the optical fiber is as shown in FIG. Figure 5 shown.

[0080] The technical advantage is that by fusing the strain monitoring fiber and the temperature monitoring fiber at the monitoring endpoint, a closed optical loop is formed, ensuring continuous transmission of the optical signal throughout the entire sensing fiber. Temperature data is independently acquired through the temperature monitoring fiber 302 and then combined with the data from the strain monitoring fiber 301 for comprehensive analysis, effectively eliminating the impact of temperature changes on strain measurements.

[0081] like Figures 3 and 4 As shown, in a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring system, the relay box 1 includes an outer shell, an optical fiber connector 102, a fixture 101 and a sealing strip; the optical fiber connector 102 is arranged in the outer shell and connected to the sensing optical fiber; the fixture 101 is installed on the outer shell and fixed at the bottom of the rail 2; the sealing strip is arranged at the connection of the outer shell.

[0082] Please refer to Figures 5 to 9 A second embodiment of the present invention provides a method for online monitoring deformation of a seamless railway rail, comprising: sequentially connecting devices in an online monitoring system for deformation of a seamless railway rail to form a closed optical loop, wherein the online monitoring system for deformation of a seamless railway rail is the system described above; calibrating each sensing optical fiber measurement section, including calibration of the start and end positions of the measurement section, calibration of measurement points within the measurement section, and calibration of corresponding points in the measurement section; debugging the equipment of the online monitoring system for deformation of a seamless railway rail; calculating the temperature change based on the acquired Brillouin frequency data, eliminating the temperature influence, calculating the actual longitudinal deformation of the rail, and identifying rail abnormalities.

[0083] In a preferred embodiment of the present invention, in the above-mentioned online monitoring method for deformation of seamless railway rails, the calibration of the starting and ending positions of the measurement area includes: using an optical fiber demodulator 4 to transmit and receive pulsed light and continuous light to the sensing optical fiber, detecting the returned Brillouin scattering signal, and obtaining a distribution curve of the Brillouin frequency along the length of the optical fiber under a reference state; applying a temperature change to the sensing optical fiber at the two end boundaries of each sensing optical fiber measurement section; due to the change in temperature of the optical cable, the Brillouin frequency at the temperature loading position will move, and an offset curve of the Brillouin frequency caused by the temperature change is obtained, and a peak is found in the offset curve. The position of the peak corresponds to the spatial position of the sensing optical fiber, and the starting point and end point of the sensing optical fiber measurement section are located.

[0084] like Figure 6 As shown, the first peak on the left is the strain monitoring area, and the first peak on the right is the temperature monitoring area. Figure 5 The starting position of the A1~A2 strain monitoring area and the B1~B2 temperature monitoring area.

[0085] Its technical effect is: by combining the calibration method of Brillouin frequency shift, temperature compensation technology and partition identification mechanism, the accuracy of the online monitoring system for seamless line rail deformation is improved.

[0086] like Figures 7 to 9 As shown, in a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the calibration of the measuring points in the measuring area includes: continuously measuring the sensing optical fiber in each sensing optical fiber measuring section to collect raw data; filtering the raw data to remove noise and invalid data to obtain a smooth signal curve, the smooth signal curve is as shown in FIG. Figure 8 As shown; analyze the smooth signal curve and extract typical characteristic parameters; check whether the extracted typical characteristic parameters meet the sine curve characteristics, if so, perform peak calculation, if not, re-collect and process the original data; perform peak calculation, identify the peak A in the smooth signal curve, mark the starting position horizontal coordinate X1 and the ending position horizontal coordinate X2 of the curve, where X2>X1; calculate the half-peak value A / 2 of the smooth signal curve, and obtain the horizontal coordinates x1, x2, ... x of the points on the smooth signal curve with the amplitude of half the peak value. i , ...; Use the full width at half maximum (FWHM) to obtain the valid data points in the sensing optical fiber measurement section. The full width at half maximum (FWHM) is used to describe the width of a function curve at half the peak value; according to X1≤x i ≤X2, and filter out the effective measuring points in each sensing optical fiber measuring section.

[0087] Its technical effect is: through continuous measurement of the sensing fiber measurement section and collection of raw data, combined with filtering processing and curve smoothing, noise and invalid data are effectively removed, and effective measurement points are accurately extracted through the half-wave full width (FWHM) method, thereby improving measurement accuracy and stability.

[0088] In a preferred embodiment of the present invention, in the above-mentioned method for online monitoring deformation of seamless railway rails, the calibration of the corresponding points in the measurement area includes: matching the points in the strain monitoring section and the temperature monitoring section one by one, with the geographical locations of the strain measuring points and the temperature measuring points being the same; obtaining the measuring point pairs in the sensing optical fiber measurement section, A 10 →B 10 ,…,A 1i →B 1i ,…,A2→B2.

[0089] Its technical effect is: by matching strain measurement points and temperature measurement points one by one, it ensures the spatial consistency of measurement data, accurately eliminates the temperature influence, and improves the monitoring accuracy, reliability and analysis efficiency of the system.

[0090] In a preferred embodiment of the present invention, in the above-mentioned online monitoring method for deformation of seamless railway rails, the equipment debugging of the online monitoring system for deformation of seamless railway rails includes: performing a longitudinal tension test on the debugging optical fiber to simulate the deformation of the rail, and verifying the sensitivity of the debugging optical fiber in sensing the strain signal and the reliability of data transmission by checking and analyzing the data changes of the monitoring signal; debugging the stability of the light source intensity of the optical fiber demodulator 4; and debugging the software acquisition mode of the industrial control computer 5.

[0091] Its technical effects are: simulating rail deformation through longitudinal tensioning tests, verifying and debugging the sensitivity of the optical fiber to strain signals, and ensuring the sensitivity and accuracy of strain signal perception; analyzing the signal transmission performance of the sensing optical fiber, ensuring that the signal can be stably transmitted to the optical fiber demodulator and industrial computer, and ensuring the stability and reliability of data transmission; ensuring the stability of the optical signal and reducing measurement errors caused by light source fluctuations by debugging the intensity of the light source; and optimizing the data acquisition process by debugging the software acquisition mode of the industrial computer, ensuring that the strain signal and temperature signal can be processed synchronously in the best way, reducing data processing delays, and improving the system's response speed and monitoring efficiency.

[0092] In a preferred embodiment of the present invention, in the above-mentioned seamless railway rail deformation online monitoring method, the temperature change is calculated based on the obtained Brillouin frequency data, the temperature effect is eliminated, and the actual longitudinal deformation of the rail is calculated. Identifying rail abnormalities includes: using the optical fiber demodulator 4 to obtain Brillouin frequency data from the strain monitoring optical fiber 301 and the temperature monitoring optical fiber 302; calculating the Brillouin frequency change Δv of the temperature monitoring optical fiber 302 at the i-th measuring point ti=v ti -v 0i , where Δv ti is the Brillouin frequency at the measurement point, v 0i is the reference frequency of the measuring point; the temperature change of the i-th measuring point is calculated Among them, k t is the frequency-temperature conversion coefficient of the temperature monitoring optical fiber 302; the frequency change Δv caused by the temperature change is calculated ∈ti =Δt i ×k ∈t , where k ∈t is the frequency-temperature conversion coefficient of the strain monitoring optical fiber 301; the Brillouin frequency change v of the strain monitoring optical fiber 301 ∈i Eliminate the frequency change Δv caused by temperature change ∈ti As well as the reference Brillouin frequency change v0 of the rail, the Brillouin frequency change Δv caused by the actual rail deformation is calculated. ∈i =v ∈i -v0-Δv ∈ti ; Calculate the rail strain at the i-th measuring point Among them, k ∈ is the strain frequency conversion coefficient of the strain monitoring optical fiber 301; according to the relationship between strain and deformation, the actual longitudinal deformation of the rail is calculated as Δl=∈ i ×L, where L is the length of the measurement area; the calculated actual longitudinal deformation is compared with the standard value to determine whether the actual longitudinal deformation exceeds the normal range, and to identify whether there are abnormal conditions such as creeping or breaking of the rail. If so, the system will issue an alarm to indicate that there may be abnormality in the rail.

[0093] The technical benefits of this approach are: by using a specialized temperature-monitoring optical fiber to obtain the temperature variation at the measuring point, and utilizing a frequency-temperature conversion coefficient to eliminate the temperature effect on the strain-monitoring optical fiber, the temperature-induced frequency variation and the reference frequency variation are removed from the Brillouin frequency variation of the strain-monitoring optical fiber, accurately obtaining the true strain frequency variation on the strain-monitoring optical fiber. This avoids misjudgments caused by ambient temperature changes and accurately calculates the Brillouin frequency variation caused by the actual rail deformation. This achieves precise separation of temperature and strain, high-precision calculation of true deformation, and rapid identification and alarm of rail anomalies.

[0094] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A method for online monitoring of seamless railway rail deformation, characterized in that: include: The devices in the seamless line rail deformation online monitoring system are connected in sequence to form an optical path closed loop, wherein the seamless line rail deformation online monitoring system comprises a sensing optical fiber, a relay box (1), an optical fiber demodulator (4) and an industrial control computer (5), wherein the sensing optical fiber is arranged at the rail waist of the rail (2) and is used to monitor the rail strain change in real time, the relay box (1) is installed at the rail bottom of the rail (2) and is connected to the sensing optical fiber and is used to mark each sensing optical fiber measurement section, the optical fiber demodulator (4) is connected to the sensing optical fiber via a jumper and is used to transmit and receive pulse light and continuous light to the sensing optical fiber and collect monitoring data of the sensing optical fiber, and the industrial control computer (5) is connected to the optical fiber demodulator (4) via a data transmission line and is used to process and analyze the monitoring data; Calibrate each sensing fiber measurement section, including calibration of the start and end positions of the measurement section, calibration of measurement points within the measurement section, and calibration of corresponding points in the measurement section; Debugging the online monitoring system for seamless rail deformation; Calculate the temperature change based on the acquired Brillouin frequency data, eliminate the temperature effect, calculate the actual longitudinal deformation of the rail, and identify rail anomalies; The calibration of the starting and ending positions of the measurement area includes: Using an optical fiber demodulator (4) to transmit and receive pulsed light and continuous light to the sensing optical fiber, detecting the returned Brillouin scattering signal, and obtaining a distribution curve of the Brillouin frequency along the length of the optical fiber under a reference state; Applying temperature changes to the sensing optical fibers at both end boundaries of each sensing optical fiber measuring section; Obtaining a Brillouin frequency shift curve caused by temperature change, searching for peaks in the shift curve, where the positions of the peaks correspond to the spatial positions of the sensing optical fiber, and locating the starting and ending points of the sensing optical fiber measurement section; The temperature variation is calculated based on the acquired Brillouin frequency data, the temperature effect is eliminated, and the actual longitudinal deformation of the rail is calculated. The identification of rail abnormalities includes: The sensing optical fiber includes a strain monitoring optical fiber (301) and a temperature monitoring optical fiber (302); The strain monitoring optical fiber (301) and the temperature monitoring optical fiber (302) are fused together at the end of a sensing optical fiber measuring section; Using an optical fiber demodulator (4) to obtain Brillouin frequency data from the strain monitoring optical fiber (301) and the temperature monitoring optical fiber (302); Calculate the Brillouin frequency change of the temperature monitoring optical fiber (302) at the i-th measuring point ,in, is the Brillouin frequency at the measurement point, is the reference frequency of the measuring point; Calculate the temperature change of the i-th measuring point ,in, The frequency-temperature conversion coefficient of the temperature monitoring optical fiber (302); Calculate the frequency change caused by temperature change ,in, is the frequency-temperature conversion coefficient of the strain monitoring optical fiber (301); The Brillouin frequency change of the strain monitoring optical fiber (301) Eliminate the frequency change caused by temperature change and the change in the rail's reference Brillouin frequency , calculate the Brillouin frequency change caused by the actual rail deformation ; Calculate the rail strain at the i-th measuring point ,in, is the strain-frequency conversion coefficient of the strain monitoring optical fiber (301); According to the relationship between strain and deformation, the actual longitudinal deformation of the rail is calculated , where L is the length of the measurement area; The calculated actual longitudinal deformation is compared with the standard value to determine whether the actual longitudinal deformation exceeds the normal range, thereby identifying whether there is an abnormality in the rail.

2. The online monitoring method for seamless railway rail deformation according to claim 1, characterized in that: The strain monitoring optical fiber (301) is connected to the starting end of the optical fiber demodulator (4) via the jumper; The temperature monitoring optical fiber (302) is connected to the end of the optical fiber demodulator (4) via the jumper.

3. The online monitoring method for seamless railway rail deformation according to claim 1, characterized in that: The relay box (1) comprises a housing, an optical fiber connector (102), a fixture (101) and a sealing strip; The optical fiber connector (102) is arranged in the housing and connected to the sensing optical fiber; The clamp (101) is mounted on the housing and fixed at the bottom of the rail (2); The sealing strip is arranged at the connection of the shell.

4. The method for online monitoring deformation of seamless railway rail according to claim 1, characterized in that: The calibration of the measuring points in the measuring area includes: Continuously measuring the sensing optical fiber within each sensing optical fiber measuring section to collect raw data; Filtering the raw data to remove noise and invalid data to obtain a smooth signal curve; Analyzing the smooth signal curve to extract typical characteristic parameters; Check whether the extracted typical characteristic parameters conform to the sine curve characteristics. If so, calculate the peak value. If not, re-collect and process the original data. Perform peak calculation to identify the peak A in the smooth signal curve, and mark the starting position abscissa X1 and the ending position abscissa X2 of the curve, where X2>X1; Calculate the half-peak value A / 2 of the smooth signal curve, and obtain the horizontal coordinates x1, x2, ... x of the points on the smooth signal curve where the amplitude is half-peak. i ,…; According to X1≤x i ≤X2, and filter out the effective measuring points in each sensing optical fiber measuring section.

5. The method for online monitoring deformation of seamless railway rail according to claim 4, characterized in that: The calibration of the corresponding points in the measurement area includes: The points in the strain monitoring section and the temperature monitoring section will be matched one by one, and the geographical locations of the strain measurement points and the temperature measurement points will be the same; A pair of measuring points within the sensing optical fiber measuring section is obtained.

6. The online monitoring method for seamless railway rail deformation according to claim 1, characterized in that: The equipment debugging of the seamless railway rail deformation online monitoring system includes: Conducting a longitudinal tension test on the debugging optical fiber to simulate rail deformation, verifying the sensitivity of the debugging optical fiber in sensing strain signals and the reliability of data transmission; Debugging the stability of the light source intensity of the optical fiber demodulator (4); Debug the software acquisition mode of the industrial computer (5).

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