Review of fiber optic sensors in geotechnical health monitoring

• Published in: Optical fiber technology 2020-01, Vol.54, p.102127, Article 102127
• Main Authors: Zheng, Yong, Zhu, Zheng-Wei, Xiao, Wang, Deng, Quan-Xiang
• Format: Article
• Language: English
• Subjects: Bend loss based fiber optic sensors; Displacement algorithms; Fiber Bragg grating sensors; Geotechnical structures; Structural health monitoring
• ISSN: 1068-5200; 1095-9912
• DOI: 10.1016/j.yofte.2019.102127

•The development of fiber optic sensors in geotechnical engineering is fully reviewed.•Three algorithms for displacement calculation were discussed by numerical simulation.•A comparison analysis of optical fiber sensors for geotechnical monitoring is given. Prediction of displacement or strain is an important means and factor for evaluating the safety of geotechnical structures, such as slopes, dams, tunnels and excavation engineering. In recent years, fiber optic displacement sensors have been extensively used in civil engineering due to their obvious advantages of light weight, high precision, strong durability, wide measurement range and long-distance transmission. This paper reviews the development of two common types of fiber optic sensors (fiber Bragg grating sensors and bend loss based fiber optic sensors) for geotechnical health monitoring, and the characteristics and the state of the art research were analyzed and discussed in details. Based on the measured strains, three algorithms for transforming monitored data to required displacement were investigated. Comparison analysis regarding typical advantages and disadvantages of these fiber optic sensing technologies for geotechnical health monitoring was also presented and discussed in this paper.