Development of deflection measurement method using smart cables with distributed fiber optic sensors

Development of deflection measurement method using smart cables with distributed fiber optic sensors

Takumi Nakashima, Kotaro Fujiwara, Makito Kobayashi, Hideaki Murayama, Michio Imai, Hideki Nagatani, Junichi Kawabata

Abstract. The monitoring behavior of civil engineering structures under and after construction secures the quality and safety of structures. There is a possibility that spot measurements, which were frequently adopted in the past, fail to notice local deformation generated in non-measured points and such local deformation is sometimes generated in the ground and the concrete. Therefore, we paid attention to displacement measurement technology using fiber optic sensors capable of performing the distributed measurement. We considered measuring long civil engineering structures with a displacement accuracy of ±1 mm and conducted demonstration experiments to investigate this feasibility. In the experiment, we utilized 3DSensors (45 m and 170 m) that have the sufficient characteristic for application to civil engineering structures, such as high workability for the ground and structures and the actual achievements of field experiments, and the TW-COTDR system capable of performing measurements with high accuracy and at long distance. As a result, we demonstrated to measure the deflection of 2.5 mm with high accuracy.

Keywords
Deflection Measurement, Distributed Fiber Optic Sensor, COTDR, Structural Monitoring, Smart Cable

Published online 3/30/2023, 7 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Takumi Nakashima, Kotaro Fujiwara, Makito Kobayashi, Hideaki Murayama, Michio Imai, Hideki Nagatani, Junichi Kawabata, Development of deflection measurement method using smart cables with distributed fiber optic sensors, Materials Research Proceedings, Vol. 27, pp 236-242, 2023

DOI: https://doi.org/10.21741/9781644902455-30

The article was published as article 30 of the book Structural Health Monitoring

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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