CN-122015937-A - Data fidelity in-service distributed optical fiber sensor repairing device and method

CN122015937ACN 122015937 ACN122015937 ACN 122015937ACN-122015937-A

Abstract

The invention discloses an in-service distributed optical fiber sensor repairing device and method for data fidelity, and relates to the technical field of structural health monitoring. The device comprises a fixed support, a supporting arm, a scale with graduations and a slidable optical fiber clamping piece, wherein the fixed support is arranged on the surface of a structure to provide a stable base, and the scale is connected with the supporting arm and is used for finely adjusting the distance between the optical fiber clamping pieces and controlling the tension of the optical fiber. The method comprises the steps of locating and cleaning break points, installing a device, clamping optical fibers, welding and repairing, adjusting the distance of clamping pieces to accurately match the initial value of the optical fiber strain before repairing, and finally packaging and curing by adopting the thickness of the epoxy resin which is theoretically designed so as to ensure that the strain transfer characteristic of a repaired section is consistent with that of an original sensor. The invention solves the problem that the data quality cannot be ensured due to the fact that the traditional repairing mode only recovers the light path, realizes the continuity and accuracy of the repairing section monitoring data through the special device and the quantization process, and remarkably improves the reliability of long-term operation of the in-service distributed optical fiber sensing system.

Inventors

SUN PANXU
HU SHAOWEI
WANG QINGFA
YE YUXIAO
SHAN CHANGXI
ZHAO YAHONG

Assignees

六合郑大科学技术转化中心
郑州大学

Dates

Publication Date: 20260512
Application Date: 20260211

Claims (6)

1. The in-service distributed optical fiber sensor repairing device for data fidelity is characterized by comprising a fixed support (1) and a supporting arm (2), wherein the fixed support (1) is connected with the surface of a structure and is used for fixing the optical fiber sensor repairing device on the surface of the structure; The optical fiber sensor is characterized in that the supporting arm (2) is connected with the scale (3), a slidable optical fiber clamping piece (4) is arranged on the scale (3) and used for clamping two ends of the optical fiber sensor to be repaired, scales are arranged on the scale (3) and used for finely adjusting the distance between the adjacent optical fiber clamping pieces (4) and adjusting the tensile force of the optical fiber.
2. The method for repairing the in-service distributed optical fiber sensor of the data fidelity is characterized by comprising the following steps: S1, positioning to a breakpoint position of a distributed optical fiber according to an effective sensing distance of optical fiber sensing equipment, and removing residual stickers of the distributed optical fiber sensor at the breakpoint position; S2, fixing the fixed support (1) on the structure surface near the break point of the optical fiber, and adjusting the direction of the support arm (2) to be consistent with the wiring direction of the distributed optical fiber; S3, holding two end parts of the broken optical fiber (5) by using optical fiber clamping pieces (4), and repairing the broken optical fiber (5) by using a new optical fiber (6); s4, after the broken optical fiber (5) is repaired, the optical fiber sensing equipment is communicated again, and the strain initial value of the optical fiber sensor is consistent with that before the optical fiber is broken by adjusting the distance of the optical fiber clamping piece (4); S5, fixing the repaired distributed optical fiber sensor by using epoxy resin (7).
3. The method for repairing an in-service distributed optical fiber sensor according to claim 2, wherein the data fidelity refers to that the repaired distributed optical fiber has the consistency of inheritance of structural deformation data before repair and deformation transmission characteristics of the sensor; the distributed optical fiber has inheritance of structural deformation data before repair, in particular to a strain average value of a repair section L Mean value of strain corresponding to segment before repair In agreement, i.e ; The uniformity of the deformation transfer characteristics of the distributed optical fiber sensor, in particular to the average strain transfer rate of the optical fiber sensor of the repairing section L Before repair In agreement, i.e 。
4. The method for repairing an in-service distributed optical fiber sensor according to claim 2, wherein the consistency of the deformation transmission characteristics of the distributed optical fiber sensor is ensured, and when the model of the repairing optical fiber is consistent with that of the initial optical fiber, the change of the deformation transmission characteristics of the distributed optical fiber sensor can be ignored; When the reinforced optical fiber or the armored optical fiber is adopted for strengthening the weak link, the shearing theory is adopted to calculate the average strain transmissibility of the optical fiber sensor in the repair area, and under the condition of ensuring the consistency of the average strain transmissibility, the thickness of the epoxy resin is redesigned, and the following equation is established: Wherein, the And Is the shear coefficient of the optical fiber sensor before and after repair and is used for measuring the strain transfer characteristic of the sensor. And Is the shear modulus of the epoxy resin before and after the repair of the optical fiber sensor, And Is the elastic modulus of the epoxy resin before and after the repair of the optical fiber sensor, And Is the thickness of the epoxy resin before and after the repair of the optical fiber sensor, And Is the radius of the optical fiber before and after the repair of the optical fiber sensor.
5. The method for repairing the in-service distributed optical fiber sensor according to claim 2, wherein the consistency of deformation transmission characteristics of the distributed optical fiber sensor is ensured, in particular to reversely calculate the required thickness of the epoxy resin by adopting a shearing theory.
6. The method for repairing an in-service distributed optical fiber sensor according to claim 2, wherein the consistency of deformation transfer characteristics of the distributed optical fiber sensor is ensured, when the length of the repairing section L is greater than 100mm, an equivalent relation between shearing coefficients can be directly established, and the following equation is established: in the case of other variables being known, only One of the required quantities, namely the thickness of the epoxy resin to be configured after repair.

Description

Data fidelity in-service distributed optical fiber sensor repairing device and method Technical Field The invention belongs to the technical field of structural health monitoring, in particular to a distributed optical fiber sensor repairing technology, and relates to an in-service distributed optical fiber sensor repairing device and method for data fidelity. Background The distributed optical fiber sensor has the unique advantages of distributed measurement, electromagnetic interference resistance, good durability and the like, and is widely applied to the field of health monitoring of civil engineering structures, in particular to long-term service performance and safety monitoring of large-scale infrastructures. The method can realize continuous spatial and time synchronous multi-parameter sensing of strain, temperature and the like along the optical fiber path, and provides an irreplaceable technical means for evaluating the whole and partial states of the structure. However, in long-term, complex and demanding in-service environments, pre-buried or surface-affixed distributed fiber optic sensors are extremely susceptible to off-the-shelf damage or breakage. Such damage can lead to interruption of the monitoring data, forming a monitoring blind zone, seriously impairing the integrity and reliability of the health monitoring system. Currently, for field repair of broken distributed optical fibers, a simple manner of fusion splicing and temporary fixing of an adhesive tape is generally adopted. The method can restore physical connectivity of the optical path, but has the obvious defects that firstly, the initial strain state of the optical fiber is difficult to accurately control in the restoration process, so that the strain initial value of the restoration section sensor is inconsistent with that before fracture, the historical continuity of monitoring data is destroyed, and secondly, a temporary fixing mode cannot ensure that a stable and reliable strain transfer interface exists between the restoration section sensor and the structure, the strain transfer characteristic of the temporary fixing mode often has difference with that of the original sensor section, so that the strain value measured by the restoration section cannot truly reflect structural deformation, and data distortion is caused. Therefore, the prior art lacks a standardized repair process and device which can be implemented on the engineering site, so that the repaired distributed optical fiber sensor can recover signal transmission, inherit structural deformation data before repair, keep the deformation transmission characteristics of the sensor consistent, and realize data fidelity repair. The existence of this problem limits the full exploitation of the potential of distributed fiber optic monitoring technology in long-life periodic infrastructure health monitoring. According to the inspection, the disclosed optical fiber sensor repairing technology is not few, but the in-service distributed optical fiber sensor repairing device and method which claim to be capable of realizing data fidelity are not inspected. The relevant schemes now partially published are listed: The Chinese patent with publication number of CN121049289A discloses a monitoring and repairing integrated optical fiber sensing system and a use method thereof, and based on the data of a monitoring and repairing integrated module and the analysis of a repairing evaluation module, the closed-loop control from crack detection and repairing to effect evaluation is realized. The Chinese patent publication No. CN106998226B discloses an intelligent health monitoring self-repairing system and method for a fiber grating sensor network, which are based on fiber grating sensors living near a damaged area to perform function compensation on a failure sensor. The Chinese patent with publication number of CN116086533A discloses a concrete structure health monitoring system and method with a self-repairing function, and the damage condition of a structure part and the repairing effect in a self-repairing state are displayed more intuitively through a BIM structure model. The Chinese patent with publication number CN116683985A discloses a fault detection and repair method of an optical fiber sensor network based on a star ring topology structure, which can detect and position a sensor fault under the condition that the optical fiber sensor network has no link failure, and can realize self-repair of the network after the optical fiber link failure. However, most of the above technologies do not mention the problem of data fidelity after repairing the optical fiber sensor, nor do they suggest that the data fidelity not only relates to strain data inheritance, but also includes the consistency of strain transfer characteristics. Therefore, an in-service distributed optical fiber sensor repairing device and method for data fidelity are urgently needed at present, and full-flow standardi