Long-term reinforcing steel bar corrosion monitoring sensor based on long-period fiber bragg grating sleeve structure

Abstract

The invention, which belongs to the technical field of structural health monitoring, provides a long-term reinforcing steel bar corrosion monitoring sensor based on a long-period fiber bragg grating sleeve structure. The long-term reinforcing steel bar corrosion monitoring sensor comprises long-period fiber bragg gratings, steel sleeves, epoxy resin parts and protective hoses. Since the sensor isbased on the high sensitivity of the long-period fiber bragg gratings to the external environment refractive index and is provided with the steel sleeves with the same components as a steel bar, the changes of resonance wavelengthes lambda 0 of the long-period fiber bragg gratings wrapped by the multiple steel sleeves with different radial lengths in the sleeve structure are monitored to realize nondestructive, long-term and quantitative monitoring of changes of the corrosion thickness of the measured reinforcing steel bar along with time, so that early warning of the corrosion state of the reinforcing steel bar is realized and the safety of a major engineering structure is guaranteed. Moreover, the sensor having a simple structure is easy to make; the monitoring process does not need complex test equipment; and the applicability is high.

Description

technical field [0001] The invention relates to a long-term steel bar long-term corrosion monitoring sensor based on a long-period optical fiber grating sleeve structure for concrete structures, belonging to the technical field of structural health monitoring, in particular to a long-term steel bar long-term corrosion monitoring sensor based on a long-period optical fiber grating sleeve structure . Background technique [0002] Concrete structure has been widely used in civil engineering construction because of its two mechanical properties of high tensile strength of steel bar and high compressive strength of concrete. It is the most widely used structural form in the world today. However, corrosion of steel bars in concrete structures has become the most important hazard threatening the durability of concrete structures worldwide. A large number of facts at home and abroad show that the concrete structure has to be stopped, overhauled or demolished and rebuilt due to corr...

AI Technical Summary

Problems solved by technology

However, these traditional methods generally have many shortcomings such as difficulty in accessing the steel bars to be tested, monitoring is destructive to the overall structure, and long-term real-time monitoring is not possible.

At present, the electrochemical corrosion monitoring method is mainly used in engineering, but the electrochemical monitoring is easily disturbed by the humidity, temperature and external electric field in the environment.

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