scholarly journals Performance of Rayleigh-Based Distributed Optical Fiber Sensors Bonded to Reinforcing Bars in Bending

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 3125 ◽  
Author(s):  
Mattia Bado ◽  
Joan Casas ◽  
António Barrias
Keyword(s):  
Optical Fiber ◽  
Experimental Tests ◽  
Optical Fiber Sensors ◽  
Strain Sensing ◽  
Fiber Sensors ◽  
Rc Structures ◽  
Multiple Sensing ◽  
Load Types ◽  
Strain Threshold ◽  
Distributed Optical Fiber

Distributed Optical Fiber Sensors (DOFSs), thanks to their multiple sensing points, are ideal tools for the detection of deformations and cracking in reinforced concrete (RC) structures, crucial as a means to ensure the safety of infrastructures. Yet, beyond a certain point of most DOFS-monitored experimental tests, researchers have come across unrealistic readings of strain which prevent the extraction of further reliable data. The present paper outlines the results obtained through an experimental test aimed at inducing such anomalies to isolate and identify the physical cause of their origin. The understanding of such a phenomenon would enable DOFS to become a truly performant strain sensing technique. The test consists of gradually bending seven steel reinforcement bars with a bonded DOFS under different conditions such as different load types, bonding adhesives, bar sections and more. The results show the bonding adhesives having an influence on the DOFS performance but not on the rise of anomalies while the reasons triggering the latter are narrowed down from six to two, reaching a strain threshold and a change in structure’s deformative behavior. Further planned research will allow identification of the cause behind the rise of strain-reading anomalies.

scholarly journals A Review of Recent Distributed Optical Fiber Sensors Applications for Civil Engineering Structural Health Monitoring

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1818
Author(s):  
Mattia Francesco Bado ◽  
Joan R. Casas
Keyword(s):  
Structural Health Monitoring ◽  
Optical Fiber ◽  
Health Monitoring ◽  
Optical Fiber Sensors ◽  
Vibration Monitoring ◽  
Fiber Sensors ◽  
Structural Health ◽  
Comprehensive Collection ◽  
Monitoring Tools ◽  
Distributed Optical Fiber

The present work is a comprehensive collection of recently published research articles on Structural Health Monitoring (SHM) campaigns performed by means of Distributed Optical Fiber Sensors (DOFS). The latter are cutting-edge strain, temperature and vibration monitoring tools with a large potential pool, namely their minimal intrusiveness, accuracy, ease of deployment and more. Its most state-of-the-art feature, though, is the ability to perform measurements with very small spatial resolutions (as small as 0.63 mm). This review article intends to introduce, inform and advise the readers on various DOFS deployment methodologies for the assessment of the residual ability of a structure to continue serving its intended purpose. By collecting in a single place these recent efforts, advancements and findings, the authors intend to contribute to the goal of collective growth towards an efficient SHM. The current work is structured in a manner that allows for the single consultation of any specific DOFS application field, i.e., laboratory experimentation, the built environment (bridges, buildings, roads, etc.), geotechnical constructions, tunnels, pipelines and wind turbines. Beforehand, a brief section was constructed around the recent progress on the study of the strain transfer mechanisms occurring in the multi-layered sensing system inherent to any DOFS deployment (different kinds of fiber claddings, coatings and bonding adhesives). Finally, a section is also dedicated to ideas and concepts for those novel DOFS applications which may very well represent the future of SHM.

scholarly journals Frequency Resolution Quantification of Brillouin-Distributed Optical Fiber Sensors

2016 ◽  
Vol 28 (21) ◽  
pp. 2367-2370 ◽  
Author(s):  
Yifei Yu ◽  
Linqing Luo ◽  
Bo Li ◽  
Kenichi Soga ◽  
Jize Yan
Keyword(s):  
Optical Fiber ◽  
Optical Fiber Sensors ◽  
Frequency Resolution ◽  
Fiber Sensors ◽  
Distributed Optical Fiber

Modal Analysis of Turbine Blades by Means of Distributed Optical Fiber Sensors

2020 ◽  
Author(s):  
Paolo Pennacchi ◽  
Gabriele Cazzulani ◽  
Alejandro Silva
Keyword(s):  
Optical Fiber ◽  
Modal Analysis ◽  
Turbine Blade ◽  
Turbine Blades ◽  
Optical Fiber Sensors ◽  
Operating Conditions ◽  
Fiber Sensors ◽  
Steam Turbine Blade ◽  
3D Printed ◽  
Distributed Optical Fiber

Abstract This paper investigates the possibility of identifying and monitoring the modal shapes of a turbine blade by means of continuous optical fiber sensors based on Optical Backscatter Reflectometry (OBR). The advantage of this approach would be the possibility of embedding the sensors in future carbon fiber blades, in order to make this modal analysis approach available also for the blade operating conditions, since no modifications in the blade fluid-structure interaction occur. The paper describes the proposed method and provides some experimental results obtained on a 3D printed model of an existing steam turbine blade.

scholarly journals Truly Distributed Optical Fiber Sensors for Structural Health Monitoring: From the Telecommunication Optical Fiber Drawling Tower to Water Leakage Detection in Dikes and Concrete Structure Strain Monitoring

2010 ◽  
Vol 2010 ◽  
pp. 1-13 ◽  
Author(s):  
Jean-Marie Henault ◽  
Gautier Moreau ◽  
Sylvain Blairon ◽  
Jean Salin ◽  
Jean-Robert Courivaud ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Optical Fibers ◽  
Brillouin Scattering ◽  
Optical Fiber Sensors ◽  
Leakage Detection ◽  
Strain Sensing ◽  
Water Leakage ◽  
Fiber Sensors ◽  
Practical Applications ◽  
Water Leakage Detection

Although optical fiber sensors have been developed for 30 years, there is a gap between lab experiments and field applications. This article focuses on specific methods developed to evaluate the whole sensing chain, with an emphasis on (i) commercially-available optoelectronic instruments and (ii) sensing cable. A number of additional considerations for a successful pairing of these two must be taken into account for successful field applications. These considerations are further developed within this article and illustrated with practical applications of water leakage detection in dikes and concrete structures monitoring, making use of distributed temperature and strain sensing based on Rayleigh, Raman, and Brillouin scattering in optical fibers. They include an adequate choice of working wavelengths, dedicated localization processes, choices of connector type, and further include a useful selection of traditional reference sensors to be installed nearby the optical fiber sensors, as well as temperature compensation in case of strain sensing.

scholarly journals Distributed Dynamic Strain Sensing Based on Brillouin Scattering in Optical Fibers

Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5629
Author(s):  
Agnese Coscetta ◽  
Aldo Minardo ◽  
Luigi Zeni
Keyword(s):  
Optical Fiber ◽  
Brillouin Scattering ◽  
Traffic Monitoring ◽  
Optical Fiber Sensors ◽  
Dynamic Strain ◽  
Dynamic Measurements ◽  
Research Activity ◽  
Fiber Sensors ◽  
Railway Traffic ◽  
Distributed Optical Fiber

Over the past three decades, extensive research activity on Brillouin scattering-based distributed optical fiber sensors has led to the availability of commercial instruments capable of measuring the static temperature/strain distribution over kilometer distances and with high spatial resolution, with applications typically covering structural and environmental monitoring. At the same time, the interest in dynamic measurements has rapidly grown due to the relevant number of applications which could benefit from this technology, including structural analysis for defect identification, vibration detection, railway traffic monitoring, shock events detection, and so on. In this paper, we present an overview of the recent advances in Brillouin-based distributed optical fiber sensors for dynamic sensing. The aspects of the Brillouin scattering process relevant in distributed dynamic measurements are analyzed, and the different techniques are compared in terms of performance and hardware complexity.

Enhancing SNR by Anisotropic Diffusion for Brillouin Distributed Optical Fiber Sensors

2020 ◽  
Vol 38 (20) ◽  
pp. 5844-5852
Author(s):  
Kuo Luo ◽  
Biwei Wang ◽  
Nan Guo ◽  
Kuanglu Yu ◽  
Changyuan Yu ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Anisotropic Diffusion ◽  
Optical Fiber Sensors ◽  
Fiber Sensors ◽  
Distributed Optical Fiber
Sign in / Sign up

Export Citation Format

Share Document