Tunnel construction full-field deformation monitoring method based on fiber-optic string monitoring technology

Abstract

This invention discloses a method for full-field deformation monitoring during tunnel construction based on fiber-optic-vibrating wire monitoring technology. Distributed strain-sensing optical fibers, backup optical fibers, and temperature-compensating optical fibers are deployed along the longitudinal direction and circumferentially along key cross-sections of the tunnel. Vibrating wire sensors are deployed at multiple monitoring sections behind the tunnel face. A unified spatial coordinate system and time reference are established to achieve mapping and matching between the optical fiber positions and vibrating wire measuring points, and to synchronously acquire multi-source data. Temperature-compensating optical fibers are used to separate and eliminate the temperature influence in the optical fiber monitoring data, and the vibrating wire sensor data is corrected based on the reference temperature. Using the corrected vibrating wire sensor data as anchor points, the longitudinal strain-sensing optical fiber and circumferential strain-sensing optical fiber monitoring data are corrected to reconstruct the full-field strain and deformation distribution of the tunnel. This invention combines the advantages of full-field coverage by longitudinal and circumferential strain-sensing optical fibers with the high-precision monitoring of vibrating wire sensors, thereby improving the accuracy, continuity, and reliability of early warning during tunnel construction deformation monitoring.

Description

Technical Field

[0001] This invention relates to the field of tunnel and underground engineering structure monitoring technology, specifically to a method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology. Background Technology

[0002] In recent years, with the gradual depletion of shallow resources and the continuous densification of transportation networks, tunnel engineering is gradually extending into deeper strata. The geological conditions faced are also changing from relatively simple soft soil or hard rock environments to extremely complex environments characterized by high ground stress. High ground stress environments are characterized by high magnitudes of ground stress fields, high levels of tectonic stress, and the resulting high concentration of secondary stress in the surrounding rock. Under these conditions, the mechanical behavior of the rock mass changes significantly, and single monitoring technologies are no longer sufficient to meet the comprehensive requirements of monitoring range, accuracy, and reliability at construction sites.

[0003] In tunnel monitoring technology, vibrating wire sensors offer high accuracy and long-term stability, but can only monitor a limited number of points and are prone to missing critical deformation areas. While longitudinal and circumferential strain sensing fibers can provide a continuous, blind-zone-free strain field distribution along the entire tunnel length, they are susceptible to baseline drift due to factors such as temperature and fiber coupling. Therefore, a method is urgently needed that integrates the advantages of both, eliminates environmental interference, and achieves accurate, full-field monitoring and early warning. Summary of the Invention

[0004] The purpose of this invention is to provide a method for full-site deformation monitoring in tunnel construction based on fiber optic-vibrating wire monitoring technology, in order to solve the problems of limited single-point monitoring range, easy omission of key deformation parts, and drift caused by temperature and coupling state in existing tunnel construction monitoring.

[0005] To achieve the above objectives, the technical solution adopted by this invention is as follows: a method for full-site deformation monitoring in tunnel construction based on fiber optic-vibrating wire monitoring technology, comprising the following steps:

[0006] Step S1: Along the length of the tunnel, longitudinal data acquisition optical fibers are arranged on the tunnel arch and both sides;

[0007] Along the length of the tunnel, select multiple tunnel cross sections and set up circumferential closed monitoring loops on the selected tunnel cross sections;

[0008] Step S2: Behind the tunnel face, select multiple tunnel cross sections from the tunnel cross sections where the circumferential closed monitoring ring has been set up as monitoring sections, and set up vibrating wire sensors at key points of each monitoring section.

[0009] Step S3: Establish a unified coordinate system and map and match the coordinates of the measuring points of the vibrating wire sensor with the positions along the optical fiber.

[0010] Step S4: Establish a unified time reference and synchronize the data acquisition time of the longitudinal data acquisition fiber and the circumferential closed monitoring ring with that of the vibrating wire sensor. Collect the tunnel's strain data and temperature data through the longitudinal data acquisition fiber and the circumferential closed monitoring ring.

[0011] Step S5: Using the collected temperature data and tunnel strain data, correct the influence of temperature on the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring ring.

[0012] Correcting the effect of temperature on monitoring data from vibrating wire sensors;

[0013] Step S6: Using the corrected monitoring data of the vibrating wire sensor as the anchor point, the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring loop that have completed temperature correction are corrected to reconstruct the strain distribution of the entire tunnel.

[0014] Based on the strain distribution throughout the tunnel, potential abnormal sections were initially located;

[0015] Using the high-precision data of the vibrating wire sensor after the monitoring section on both sides of the abnormal section is corrected as the anchor point, the interpolation method is used to verify and confirm these abnormal sections. At the same time, the manual experience judgment method is used to eliminate false alarm data caused by poor fiber coupling and other reasons.

[0016] Preferably, in step S1, the longitudinal data acquisition fiber includes: a longitudinal strain sensing fiber, a spare longitudinal strain sensing fiber, and a longitudinal temperature compensation fiber, with the longitudinal strain sensing fiber and the spare longitudinal strain sensing fiber running through the front and back of the tunnel.

[0017] The circumferential closed monitoring loop includes: a closed circumferential strain sensing fiber, a spare circumferential strain sensing fiber, and a circumferential temperature compensation fiber. The circumferential strain sensing fiber, the spare circumferential strain sensing fiber, and the circumferential temperature compensation fiber are continuously laid around the tunnel perimeter to form a circumferential closed monitoring loop.

[0018] The longitudinal temperature compensation fiber and the circumferential temperature compensation fiber are deployed in a relaxed, free state.

[0019] The longitudinal temperature compensation fiber is arranged side by side next to the longitudinal strain sensing fiber. The longitudinal strain sensing fiber and the circumferential strain sensing fiber are arranged in a straight tensioned manner. The longitudinal strain sensing fiber, the spare longitudinal strain sensing fiber, the longitudinal temperature compensation fiber and the circumferential strain sensing fiber, the spare circumferential strain sensing fiber, the circumferential temperature compensation fiber are connected in a one-to-one correspondence with each other.

[0020] Preferably, in step S2, the key points include the arch crown, arch waist, side walls, and invert arch;

[0021] When installing a vibrating wire sensor, record the ambient temperature at the time of installation as the reference temperature for subsequent temperature correction.

[0022] Preferably, step S3 includes the following sub-steps:

[0023] Step S31: Use a total station to measure the coordinates of the following points: the three-dimensional coordinates of the vibrating wire sensor installation point, the coordinates of the circumferential closed monitoring ring at key points such as the arch crown and arch waist, and the coordinates of the center point of the monitoring section.

[0024] Step S32: Record the fiber optic mileage values ​​corresponding to each key point of the circumferential closed monitoring loop;

[0025] Step S33: Establish a direct spatial correspondence between the optical fiber path and the vibrating wire measurement point using the key point measurement method.

[0026] Preferably, in step S32, the method for determining the fiber optic mileage value corresponding to each key point of the circumferential closed monitoring loop is as follows: along the fiber optic line, select and measure the spatial coordinates of several feature points, where the feature points are the points directly above the vibrating wire sensor, and convert the fiber optic length value corresponding to the feature points to form a correspondence between length and coordinates.

[0027] Preferably, in step S4, the unified time reference is Beijing time, and the sampling time of the vibrating wire sensor is used as the reference time axis. The dense acquisition sequences of the longitudinal strain sensing fiber and the circumferential strain sensing fiber are downsampled and extracted using the nearest neighbor time matching algorithm.

[0028] Preferably, in step S5, the method for eliminating the influence of temperature on the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring loop includes:

[0029] The true strain change is separated from the total Brillouin frequency shift measured by the longitudinal and circumferential temperature-compensated fibers, respectively, using the temperature changes measured by the longitudinal and circumferential strain-sensing fibers. Specifically:

[0030] According to the Brillouin scattering principle, the change in Brillouin frequency shift... With temperature change and strain changes The relationship is:

[0031] ;

[0032] Where CνT is the temperature coefficient; Cνε is the strain coefficient;

[0033] Strain change at longitudinal or circumferential temperature-compensating fiber =0, therefore the frequency shift measured by the temperature-compensated fiber is 0. for:

[0034] ;

[0035] The temperature change was calculated. :

[0036] ;

[0037] For longitudinal strain sensing fiber or circumferential strain sensing fiber, the total frequency shift is measured. :

[0038] ;

[0039] Then the change in strain for:

[0040] .

[0041] Preferably, in step S5, the method for correcting the influence of temperature on the monitoring data of the vibrating wire sensor is as follows:

[0042] Based on the reference temperature at the time of installation of the vibrating wire sensor, the correction is made according to the following formula:

[0043] ;

[0044] in, To provide a corrected and realistic response, The strain value is directly measured by the sensor. is the coefficient of linear expansion of the structure. is the coefficient of linear expansion of the sensor housing.

[0045] Preferably, the method further includes step S7, which involves determining the safety status of the tunnel structure based on the corrected tunnel full-field monitoring data and issuing graded warnings according to preset warning levels.

[0046] The tiered early warning system includes at least blue, yellow, orange, and red alerts, each corresponding to different degrees of deformation and corresponding response measures.

[0047] Preferably, in step S7, the response measures include:

[0048] Blue Alert: A warning notification will be sent to on-site technical personnel;

[0049] Yellow alert: Send information to the project's technical manager and supervisor and organize on-site verification;

[0050] Orange alert: Information is sent to all relevant parties and the emergency management plan is activated;

[0051] Red Alert: Activate audible and visual alarms, organize personnel evacuation, and simultaneously push alarm information to relevant units and rescue agencies.

[0052] Compared with the prior art, the beneficial effects of the present invention are:

[0053] 1. Full coverage and high precision: This invention utilizes the full distribution of longitudinal strain sensing fiber and circumferential strain sensing fiber without blind spots, combined with the high-precision anchor point correction of vibrating wire sensor, to achieve accurate capture of the strain distribution across the entire tunnel. When combined with structural mechanical parameters or pressure sensor data, the stress state of the support structure or surrounding rock can be further obtained.

[0054] 2. Strong anti-interference capability and reliable early warning: This invention eliminates fiber temperature drift by using temperature-compensated fiber and cross-verifies abnormal fiber sections using vibrating wire data, effectively eliminating environmental interference and false alarms, and ensuring the reliability of early warning triggering.

[0055] 3. Advanced early warning and proactive prevention: This invention is based on the data fusion of optical fiber and vibrating wire to capture early signs of deformation, establish a hierarchical early warning mechanism, realize timely early warning of abnormal states of tunnel structures, and transform passive emergency rescue into proactive prevention.

[0056] 4. High system survivability and full-cycle applicability: The optical fiber and vibrating wire of this invention serve as backups for each other. By using backup optical fiber and multi-source sensor data for verification, the robustness of the monitoring system is improved, and it can be used throughout the tunnel construction and operation periods. Attached Figure Description

[0057] Figure 1 This is a flowchart of the tunnel construction full-site deformation monitoring method based on fiber optic-vibrating wire monitoring technology of the present invention. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0059] Please see Figure 1 The present invention discloses a method for monitoring full-site deformation during tunnel construction based on fiber optic-vibrating wire monitoring technology, comprising the following steps:

[0060] Step S1: Along the length of the tunnel, longitudinal data acquisition optical fibers are arranged on the tunnel arch and both sides. Along the length of the tunnel, multiple tunnel cross sections are selected, and circumferential closed monitoring loops are set up on the selected tunnel cross sections.

[0061] The longitudinal data acquisition fiber includes: longitudinal strain sensing fiber, backup longitudinal strain sensing fiber and longitudinal temperature compensation fiber. The longitudinal strain sensing fiber and backup longitudinal strain sensing fiber run through the front and back of the tunnel.

[0062] The circumferential closed monitoring loop includes: a closed circumferential strain sensing fiber, a spare circumferential strain sensing fiber, and a circumferential temperature compensation fiber. The circumferential strain sensing fiber, the spare circumferential strain sensing fiber, and the circumferential temperature compensation fiber are continuously laid around the tunnel perimeter to form a circumferential closed monitoring loop.

[0063] The longitudinal temperature compensation fiber and the circumferential temperature compensation fiber are deployed in a relaxed, free state.

[0064] The longitudinal temperature compensation fiber is arranged side by side next to the longitudinal strain sensing fiber. The longitudinal strain sensing fiber and the circumferential strain sensing fiber are arranged in a straight tensioned manner. The longitudinal strain sensing fiber, the spare longitudinal strain sensing fiber, the longitudinal temperature compensation fiber and the circumferential strain sensing fiber, the spare circumferential strain sensing fiber, the circumferential temperature compensation fiber are connected in a one-to-one correspondence with each other.

[0065] Temperature-compensating fiber and strain-sensing fiber are in the same temperature field but are not affected by strain, and are used to eliminate the interference of temperature on fiber monitoring data.

[0066] The signals output from the longitudinal strain sensing fiber, the backup longitudinal strain sensing fiber, and the longitudinal temperature compensation fiber are all transmitted to the data processing platform.

[0067] Step S2: Behind the tunnel face, select multiple tunnel cross sections from the tunnel cross sections where the circumferential closed monitoring ring has been installed as monitoring sections. Install vibrating wire sensors at key points of each monitoring section. The key points include the arch crown, arch waist, sidewalls and invert. Record the ambient temperature when installing the vibrating wire sensors as the reference temperature for subsequent temperature correction.

[0068] Step S3: Establish a unified spatial coordinate system and map and match the coordinates of the measuring points of the vibrating wire sensor with the positions along the optical fiber.

[0069] Step S31: Use a total station to measure the coordinates of the following points: the three-dimensional coordinates of the vibrating wire sensor installation point, the coordinates of the circumferential closed monitoring ring at key points such as the arch crown and arch waist, and the coordinates of the center point of the monitoring section.

[0070] Step S32: Record the fiber optic mileage value corresponding to each key point of the circumferential closed monitoring loop. The method for determining the fiber optic mileage value corresponding to each key point of the circumferential closed monitoring loop is as follows: Select and measure the spatial coordinates of several feature points along the fiber optic line. The feature point is the point directly above the vibrating wire sensor. Convert the fiber optic length value corresponding to the feature point to form the correspondence between length and coordinate.

[0071] Step S33: Establish the direct spatial correspondence between the optical fiber path and the vibrating wire measurement point using the key point measurement method;

[0072] Step S4: Establish a unified time reference and synchronize the data acquisition time of the longitudinal data acquisition fiber and the circumferential closed monitoring ring with that of the vibrating wire sensor. Collect the tunnel's strain data and temperature data through the longitudinal data acquisition fiber and the circumferential closed monitoring ring.

[0073] The unified time reference is Beijing time. The sampling time of the vibrating wire sensor is used as the reference time axis. The dense acquisition sequences of the longitudinal strain sensing fiber and the circumferential strain sensing fiber are downsampled and extracted using the nearest neighbor time matching algorithm.

[0074] Step S5: Using the collected temperature data and tunnel strain data, correct the influence of temperature on the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring ring.

[0075] Methods to eliminate the influence of temperature on strain data of longitudinal data acquisition fiber and circumferential closed monitoring loop include:

[0076] The true strain change is separated from the total Brillouin frequency shift measured by the longitudinal and circumferential temperature-compensated fibers, respectively, using the temperature changes measured by the longitudinal and circumferential strain-sensing fibers. Specifically:

[0077] According to the Brillouin scattering principle, the change in Brillouin frequency shift... With temperature change and strain changes The relationship is:

[0078] ;

[0079] Where CνT is the temperature coefficient; Cνε is the strain coefficient;

[0080] Strain change at longitudinal or circumferential temperature-compensating fiber Therefore, the frequency shift measured by the temperature-compensated fiber optic cable... for:

[0081] ;

[0082] The temperature change was calculated. :

[0083] ;

[0084] For longitudinal strain sensing fiber or circumferential strain sensing fiber, the total frequency shift is measured. :

[0085] ;

[0086] Then the change in strain for:

[0087] ;

[0088] The method to correct for the influence of temperature on the monitoring data of a vibrating wire sensor is as follows:

[0089] Based on the reference temperature at the time of installation of the vibrating wire sensor, the correction is made according to the following formula:

[0090] ;

[0091] in, To provide a corrected and realistic response, The strain value is directly measured by the sensor. is the coefficient of linear expansion of the structure. The coefficient of linear expansion of the sensor housing;

[0092] Step S6: Using the corrected monitoring data of the vibrating wire sensor as the anchor point, the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring loop that have completed temperature correction are corrected to reconstruct the strain distribution of the entire tunnel.

[0093] Based on the strain distribution throughout the tunnel, potential abnormal sections were initially located;

[0094] Using the high-precision data of the vibrating wire sensor after the monitoring section on both sides of the abnormal section is corrected as the anchor point, the interpolation method is used to verify and confirm these abnormal sections. At the same time, the manual experience judgment method is used to eliminate false alarm data caused by poor fiber coupling, etc.

[0095] The specific steps for correcting the monitoring data of longitudinal strain sensing fiber and circumferential strain sensing fiber using interpolation and neural network algorithms are as follows:

[0096] Using the distance between key monitoring sections as the interpolation interval, a linear interpolation method is used to obtain vibrating wire monitoring data near the monitoring sections. In the tunnel circumferential direction, with the center of the tunnel section as the origin, the rectangular coordinates of the measuring points are converted to polar coordinates. A cubic spline interpolation function is established between the polar angle of the measuring points and the radial deformation to calculate the radial strain data of vibrating wire monitoring at any angle position. Similarly, using fiber optic monitoring data, the distance between key monitoring sections is used as the interpolation interval, and an interpolation method is used to obtain vibrating wire monitoring data in the area near the section where no pipeline monitoring is installed.

[0097] For areas to be predicted that are far from the monitoring section, a neural network model is used for prediction. The input parameters of the neural network include: location, fiber optic monitoring index data, temperature-compensated fiber optic data, and distance from the vibrating wire monitoring point.

[0098] The training samples are: vibrating wire monitoring cross-section data, vibrating wire monitoring data obtained by interpolation method from nearby cross-sections, and fiber optic monitoring data. 70-80% of the data is used for model training, and the remaining 20-30% is used for validation. The fiber optic monitoring feature values ​​of the points to be predicted that are far away from the vibrating wire monitoring cross-section are input into the trained neural network model to predict the vibrating wire monitoring values ​​of the cross-sections that are far away.

[0099] For cross sections that are far from the vibrating wire sensor, the same method is used: taking the center of the tunnel cross section as the origin, converting the rectangular coordinates of the measuring point into polar coordinates, establishing a cubic spline interpolation function between the polar angle of the measuring point and the radial deformation, calculating the radial deformation at any angle position, and obtaining fiber optic monitoring data.

[0100] Based on the distance between the point to be corrected and the vibrating wire monitoring point, vibrating wire monitoring data predicted by the neural network algorithm and fiber optic monitoring data obtained by interpolation are obtained at greater distances from the monitoring section. In the vicinity of the monitoring section, radial fiber optic monitoring data and radial vibrating wire monitoring data obtained by interpolation are obtained. Different weights are assigned according to the distance from the actual monitoring section: closer to the vibrating wire monitoring point, interpolation is dominant, and vibrating wire monitoring data is given a larger weight; at greater distances, the neural network algorithm is dominant, and vibrating wire monitoring data is given a smaller weight. The weighted deformation value is calculated using the formula:

[0101] ;

[0102] in, Weighting of fiber optic monitoring data; Fiber optic monitoring of strain data, Weighting of vibrating wire monitoring data; Vibrating wire monitoring strain data;

[0103] The fused full-field data is corrected using a portion of the reserved vibrating wire sensor monitoring data. If the correction results are consistent, the next procedure is performed; otherwise, manual verification is conducted and the fusion weights are adjusted.

[0104] Step S7: Based on the corrected full-site monitoring data of the tunnel, determine the safety status of the tunnel structure and issue graded warnings according to the preset warning levels;

[0105] The tiered early warning system includes at least blue, yellow, orange, and red alerts, each corresponding to different degrees of disruption and corresponding response measures.

[0106] Blue alert (Level IV), Yellow alert (Level III), Orange alert (Level II), Red alert (Level I);

[0107] Blue Alert (Level IV): The system automatically sends an alert notification (SMS / APP / platform pop-up) to on-site technical personnel;

[0108] Yellow Alert (Level III): The system simultaneously pushes the alert information to the project's technical manager and supervision unit; organizes the technical manager and supervision unit to conduct on-site verification and professional diagnosis, and analyzes the causes and trends of deformation;

[0109] Orange Alert (Level II): The system pushes the warning information to all relevant parties, including the construction unit, the person in charge of the construction unit, the supervision unit, and the design unit; the emergency management plan is activated, and on-site personnel are prepared to evacuate at any time;

[0110] Red Alert (Level I): The sound and light alarm and loudspeaker will be activated immediately on site to sound the alarm; all personnel and vehicles in the tunnel will be directed to evacuate along the escape route immediately; the alarm information will be pushed to all relevant units and rescue agencies through the intelligent management and control platform.

[0111] The monitoring center platform automatically pops up windows and issues audible and visual alarms, pushes text messages and APP notifications to relevant responsible persons, and issues alarms directly to on-site personnel and passing vehicles at locations such as tunnel entrances and key passages through audible and visual alarms and variable message signs.

[0112] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes that can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention are all within the protection scope of the claims of the present invention.

Claims

1. A method for monitoring deformation throughout tunnel construction based on fiber optic-vibrating wire monitoring technology, characterized in that, Includes the following steps: Step S1: Along the length of the tunnel, longitudinal data acquisition optical fibers are arranged at the tunnel arch and both sides. Along the length of the tunnel, select multiple tunnel cross sections and set up circumferential closed monitoring loops on the selected tunnel cross sections; Step S2: Behind the tunnel face, select multiple tunnel cross sections from the tunnel cross sections where the circumferential closed monitoring ring has been set up as monitoring sections, and set up vibrating wire sensors at key points of each monitoring section. Step S3: Establish a unified coordinate system and map and match the coordinates of the measuring points of the vibrating wire sensor with the positions along the optical fiber. Step S4: Establish a unified time reference and synchronize the data acquisition time of the longitudinal data acquisition fiber and the circumferential closed monitoring ring with that of the vibrating wire sensor. Collect the tunnel's strain data and temperature data through the longitudinal data acquisition fiber and the circumferential closed monitoring ring. Step S5: Using the collected temperature data and tunnel strain data, correct the influence of temperature on the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring ring. Correcting the effect of temperature on monitoring data from vibrating wire sensors; Step S6: Using the corrected monitoring data of the vibrating wire sensor as the anchor point, the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring loop that have completed temperature correction are corrected to reconstruct the strain distribution of the entire tunnel. Based on the strain distribution throughout the tunnel, potential abnormal sections were initially located; Using the high-precision data of the vibrating wire sensor after the monitoring section on both sides of the abnormal section is corrected as the anchor point, the interpolation method is used to verify and confirm these abnormal sections. At the same time, the manual experience judgment method is used to eliminate false alarm data caused by poor fiber coupling and other reasons.

2. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, In step S1, the longitudinal data acquisition fiber includes: a longitudinal strain sensing fiber, a spare longitudinal strain sensing fiber, and a longitudinal temperature compensation fiber. The longitudinal strain sensing fiber and the spare longitudinal strain sensing fiber pass through the front and back of the tunnel. The circumferential closed monitoring loop includes: a closed circumferential strain sensing fiber, a spare circumferential strain sensing fiber, and a circumferential temperature compensation fiber. The circumferential strain sensing fiber, the spare circumferential strain sensing fiber, and the circumferential temperature compensation fiber are continuously laid around the tunnel perimeter to form a circumferential closed monitoring loop. The longitudinal temperature compensation fiber and the circumferential temperature compensation fiber are deployed in a relaxed, free state. The longitudinal temperature compensation fiber is arranged side by side next to the longitudinal strain sensing fiber. The longitudinal strain sensing fiber and the circumferential strain sensing fiber are arranged in a straight tensioned manner. The longitudinal strain sensing fiber, the spare longitudinal strain sensing fiber, the longitudinal temperature compensation fiber and the circumferential strain sensing fiber, the spare circumferential strain sensing fiber, the circumferential temperature compensation fiber are connected in a one-to-one correspondence with each other.

3. The method for monitoring full-site deformation during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, In step S2, the key points include the arch crown, arch waist, side walls, and invert arch; When installing a vibrating wire sensor, record the ambient temperature at the time of installation as the reference temperature for subsequent temperature correction.

4. The method for monitoring full-site deformation during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, Step S3 includes the following sub-steps: Step S31: Use a total station to measure the coordinates of the following points: the three-dimensional coordinates of the vibrating wire sensor installation point, the coordinates of the circumferential closed monitoring ring at key points such as the arch crown and arch waist, and the coordinates of the center point of the monitoring section. Step S32: Record the fiber optic mileage values ​​corresponding to each key point of the circumferential closed monitoring loop; Step S33: Establish a direct spatial correspondence between the optical fiber path and the vibrating wire measurement point using the key point measurement method.

5. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 4, characterized in that, In step S32, the method for determining the fiber optic mileage value corresponding to each key point of the circumferential closed monitoring loop is as follows: along the fiber optic line, select and measure the spatial coordinates of several feature points, where the feature points are the points directly above the vibrating wire sensor, and convert the fiber optic length value corresponding to the feature points to form a correspondence between length and coordinates.

6. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, In step S4, the unified time reference is Beijing time. The sampling time of the vibrating wire sensor is used as the reference time axis. The dense acquisition sequences of the longitudinal strain sensing fiber and the circumferential strain sensing fiber are downsampled and extracted using the nearest neighbor time matching algorithm.

7. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, In step S5, the method for eliminating the influence of temperature on the strain data of the longitudinal data acquisition fiber and the circumferential closed monitoring loop includes: The true strain change is separated from the total Brillouin frequency shift measured by the longitudinal and circumferential temperature-compensated fibers, respectively, using the temperature changes measured by the longitudinal and circumferential strain-sensing fibers. Specifically: According to the Brillouin scattering principle, the change in Brillouin frequency shift... With temperature change and strain changes The relationship is: ； Where CνT is the temperature coefficient; Cνε is the strain coefficient; Strain change at longitudinal or circumferential temperature-compensating fiber =0, therefore the frequency shift measured by the temperature-compensated fiber is 0. for: ； The temperature change was calculated. : ； For longitudinal strain sensing fiber or circumferential strain sensing fiber, the total frequency shift is measured. : ； Then the change in strain for: 。 8. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 7, characterized in that, In step S5, the method for correcting the influence of temperature on the monitoring data of the vibrating wire sensor is as follows: Based on the reference temperature at the time of installation of the vibrating wire sensor, the correction is made according to the following formula: ； in, To provide a corrected and realistic response, The strain value is directly measured by the sensor. is the coefficient of linear expansion of the structure. is the coefficient of linear expansion of the sensor housing.

9. The method for monitoring full-site deformation during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 1, characterized in that, It also includes step S7, which, based on the corrected full-field monitoring data of the tunnel, determines the safety status of the tunnel structure and issues graded warnings according to the preset warning levels; The tiered early warning system includes at least blue, yellow, orange, and red alerts, each corresponding to different degrees of deformation and corresponding response measures.

10. The method for full-site deformation monitoring during tunnel construction based on fiber optic-vibrating wire monitoring technology according to claim 9, characterized in that, In step S7, the response measures include: Blue Alert: A warning notification will be sent to on-site technical personnel; Yellow alert: Send information to the project's technical manager and supervisor and organize on-site verification; Orange alert: Information is sent to all relevant parties and the emergency management plan is activated; Red Alert: Activate audible and visual alarms, organize personnel evacuation, and simultaneously push alarm information to relevant units and rescue agencies.

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