Long-gauge coaxial multi-sleeve packaged fiber grating sensor for measuring tensile-compressive strain

Abstract

The invention relates to a long-gauge coaxial multi-sleeve packaged fiber grating sensor for measuring tensile-compressive strain, which comprises a bare fiber, a fiber grating, a short sleeve, fiberadhesive, a packaging long pipe, silicon rubber, a semi-hard pipe and a jumper wire, wherein the two ends of the fiber grating are connected with the bare fiber; the short sleeve sleeves the outer side of the fiber grating; the fiber adhesive is injected into the short sleeve; the two ends of the short sleeve are respectively connected with the packaging long pipe through the fiber adhesive; theend part of the packaging long pipe is sealed by the silicon rubber; and the bare fiber penetrates through the packaging long pipe and the silicon rubber and extends outside the packaging long pipe. According to the invention, the axial strain in a long gauge is obtained through the optical fiber grating, the monitoring range is large, the sensitivity is high, the electromagnetic interference resistance and the corrosion resistance are achieved, and the full-life cycle monitoring of the component strain can be achieved. The sensor has the advantages of small size, sealing and strong environmental adaptability, and can be applied not only to buildings, but also to strain monitoring of bridges.

Description

technical field [0001] Based on the optical fiber grating technology, the invention is a long-gauge-length coaxial multi-sleeve packaged optical fiber grating sensor for measuring tensile and compressive strains, and belongs to the technical field of optical fiber sensing. Background technique [0002] During the construction and operation of large buildings and bridges, the monitoring of their structural stress status is of great significance. Fiber Bragg grating (FBG) sensor is the preferred sensor for structural health monitoring. It can sense the change of strain and temperature through the change of light wavelength. It has many advantages, such as high precision, small and light weight, wide frequency band and good sensitivity. , strong anti-interference, small transmission loss, convenient distribution and quasi-distributed measurement, and low maintenance costs, suitable for long-term monitoring. However, most of the FBG sensors in actual engineering are point-type ...

AI Technical Summary

Problems solved by technology

However, most of the FBG sensors in actual engineering are point-type or short-gauge sensors, and their measurement range is small, and the measurement results cannot reflect the stress state of the entire structure.

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