Comparison of methods of monitoring structure deformations based on tests of a column-plate slab

This work includes a comparison of the methods of monitoring the deformations of a structure on the example of a flat plate slab test. Classic ESG (electrofusion strain gauges) and modern DFOS (distributed fiber optic sensors) were compared. During the research, both types of sensors were used on some of the reinforcing bars. The study aims to indicate the differences between the compared monitoring methods, both in terms of the obtained results and their utility values.

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Monitoring Strategic Hydraulic Infrastructures by Brillouin Distributed Fiber Optic Sensors

Water ◽

10.3390/w14020188 ◽

2022 ◽

Vol 14 (2) ◽

pp. 188

Author(s):

Manuel Bertulessi ◽

Daniele Fabrizio Bignami ◽

Ilaria Boschini ◽

Marco Brunero ◽

Maddalena Ferrario ◽

...

Keyword(s):

Fiber Optic ◽

Fiber Optic Sensors ◽

Strain Gauges ◽

Mountain Valley ◽

Concrete Members ◽

Strain Monitoring ◽

Hydropower Plants ◽

Complex Structural ◽

Monitoring Technologies

We present a case study of a Structural Health Monitoring (SHM) hybrid system based on Brillouin Distributed Fiber Optic Sensors (D-FOS), Vibrating Wire (VW) extensometers and temperature probes for an existing historical water penstock bridge positioned in a mountain valley in Valle d’Aosta Region, Northwestern Italy. We assessed Brillouin D-FOS performances for this kind of infrastructure, characterized by a complex structural layout and located in a harsh environment. A comparison with the more traditional strain monitoring technology offered by VW strain gauges was performed. The D-FOS strain cable has been bonded to the concrete members using a polyurethane-base adhesive, ensuring a rigid strain transfer. The raw data from all sensors are interpolated on a unique general timestamp with hourly resolution. Strain data from D-FOS and VW strain gauges are then corrected from temperature effects and compared. Considering the inherent differences between the two monitoring technologies, results show a good overall matching between strain time series collected by D-FOS and VW sensors. Brillouin D-FOS proves to be a good solution in terms of performance and economic investment for SHM systems on complex infrastructures such as hydropower plants, which involve extensive geometry combined with the need for detailed and continuous strain monitoring.

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New Fabry-Perot Fiber-Optic Sensors for Structural and Geotechnical Monitoring Applications

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1596-06 ◽

1997 ◽

Vol 1596 (1) ◽

pp. 39-44 ◽

Cited By ~ 3

Author(s):

P. Choquet ◽

R. Leroux ◽

F. Juneau

Keyword(s):

Strain Gauge ◽

Fiber Optic ◽

Fiber Optic Sensors ◽

Strain Gauges ◽

Surface Type ◽

Geotechnical Monitoring ◽

Fabry Perot ◽

Monitoring Applications ◽

New Sensors ◽

Accuracy And Repeatability

A new line of fiber-optic sensors suited for structural and geotechnical monitoring purposes is presented. A Fabry-Perot strain gauge is contained in each of the new sensors introduced here: four embedded and surface-type strain gauges and one type of temperature gauge. Described here are the working and reading principles of the basic Fabry-Perot strain gauge. One of the gauge’s features that allows for temperature-compensated or noncompensated measurements is described, and the various sensors constructed around the gauge are presented. These newly developed sensors exhibit high accuracy and repeatability, as illustrated by various calibration tests reported here.

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Human psychophysiological activity monitoring methods using fiber optic sensors

10.1117/12.864667 ◽

2010 ◽

Cited By ~ 1

Author(s):

M. Zyczkowski ◽

B. Uzieblo-Zyczkowska

Keyword(s):

Fiber Optic ◽

Fiber Optic Sensors ◽

Activity Monitoring ◽

Monitoring Methods

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Research of Data Processing Algorithms from Fiber Optic Sensors

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.a1095.1191s19 ◽

2019 ◽

Vol 9 (1S) ◽

pp. 456-461

Keyword(s):

Fiber Optic ◽

Optimal Algorithm ◽

Diagnostic System ◽

Fiber Optic Sensors ◽

Strain Gauges ◽

Diagnostic Systems ◽

Bench Experiment ◽

Splitting Problem ◽

Processing Algorithms ◽

Physical Principles

The article considers the phenomenon of splitting the spectrum of the reflected signal from fiber-optic sensors (FOS) based on fiber Bragg gratings (FBG), due to which errors in calculating the strain values in diagnostic systems of the stress-strain state occur. The physical principles of splitting and their influence on the diagnostic system as a whole are considered. Various algorithms are proposed to solve the splitting problem, followed by their comparison. The optimal algorithm for processing the digitized optical spectra of signals from FOS was estimated using a mathematical model using real strain indicators from a bench experiment. FOS deformation data were obtained during an experiment on a bench for bending metal levers and were compared with strain gauges.

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