A Review of Distributed Optical Fiber Sensors for Civil Engineering Applications

Abstract

The application of structural health monitoring (SHM) systems to civil engineering structures has been a developing studied and practiced topic, that has allowed for a better understanding of structures’ conditions and increasingly lead to a more cost-effective management of those infrastructures. In this field, the use of fiber optic sensors has been studied, discussed and practiced with encouraging results. The possibility of understanding and monitor the distributed behavior of extensive stretches of critical structures it’s an enormous advantage that distributed fiber optic sensing provides to SHM systems. In the past decade, several R & D studies have been performed with the goal of improving the knowledge and developing new techniques associated with the application of distributed optical fiber sensors (DOFS) in order to widen the range of applications of these sensors and also to obtain more correct and reliable data. This paper presents, after a brief introduction to the theoretical background of DOFS, the latest developments related with the improvement of these products by presenting a wide range of laboratory experiments as well as an extended review of their diverse applications in civil engineering structures.

Phase-sensitive OTDR probe pulse shapes robust against modulation-instability fading

“…Distributed optical fiber sensing using Rayleigh-based phase sensitive optical time-domain reflectometry (φOTDR) is gaining a great deal of interest in areas such as structure health monitoring, aerospace or material processing [1,2]. φOTDR-based sensors are routinely employed for the monitoring of mechanical variations (e.g., vibrations, displacements, etc.)…”

Experiment and Numerical Study on Deformation Measurement of Cast-in-Place Concrete Large-Diameter Pipe Pile Using Optical Frequency Domain Reflectometer Technology

“…The strain precisions are OFDR (1 με), BOTDR (40 με), BOTDA (20 με), BOFDA (2 με), BOCDA (10 με), FBG (1 με). The OFDR is a type of DOFS technologies which has shorter measuring time, higher sensitivity, and higher spatial resolution than other frequently-used DOFS technologies like BOTDR, BOTDA, BOFDA, BOCDA, and so on [10][11][12][13][14][15][16][17][18][19][20][21][22][23].…”

Distributed Fiber Optical Technology for Damage Identification of Engineering Structure

“…The principle is to transform photon energy into electric field and current by means of semiconductor with specific structure, and its quantum efficiency is 80~90%. Barrias, A. et al [6] found that the singular area of internal temperature in buildings would not be detected inevitably because of a large layout spacing of thermistor thermometers and other reasons. Fiber optic sensing is developed with the development of optical communication and the development of IT industry.…”

“…After fitting the sensing data of 2 sliding optical fibers, we can draw a conclusion that the coefficient & 1 and & 2 are close to each other. We can get the data fitting of & 1 and & 2 in pairs using formula (6) in several groups of experiments, and get the values of multiple groups of & 1 and & 2 respectively, and then we can get the average value. By calculating these values produced thereof , we can have the correlation between light loss A and sliding distance !…”