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Title: Corrosion Localization of Steel Structures Using Fiber Bragg Grating Sensors
Steel, which has high tension and compression strength, is a widely used civil engineering material in constructing building, bridge, pipelines, and other structures. However, steel has a well-known weakness, which is suspected to corrosion. Steel corrosion would significantly impact the reliability and safety of steel structures. Accurately locating and assessing the corrosion of steel structures would contribute to timely maintenance and thus, extend the service life of the steel structures. Although advances have been made to use nondestructive evaluation (NDE) technologies to locate and assess corrosion on steel structures, due to the lack of labor and budget for frequent NDE assessment on steel structures, remote and real-time approaches to locate and assess corrosion are still in great needs. Fiber optic sensors, especially, fiber Bragg gating (FBG) sensors, with unique advantages of real-time sensing, compactness, immune to EMI and moisture, capability of quasi-distributed sensing, and long life cycle, will be a perfect candidate for long-term corrosion assessment. However, due to the fact that FBG is a localized sensor, it is very challenging to locate corrosion using FBG sensors. In this study, algorithms are developed to locate corrosion on steel structures using FBG sensors. Detail sensing principle, localization algorithm development and calibration more » are introduced in this paper together with experimental validation testing. Upon validation, the developed corrosion localization algorithm could give some guidance to locate corrosion using in-situ FBG sensors on steel structures across nation and would possibly reduce the corrosion induced tragedies. « less
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Journal Name:
Proceedings 9th International Conference on Structural Health Monitoring of Intelligent Infrastructure
Sponsoring Org:
National Science Foundation
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