A review of measurement calibration and interpretation for seepage monitoring by optical fiber distributed temperature sensors

Ghafoori, Yaser (author), Vidmar, Andrej (author), Říha, Jaromir (author), Kryžanowski, Andrej (author)

Seepage flow through embankment dams and their sub-base is a crucial safety concern that can initiate internal erosion of the structure. The thermometric method of seepage monitoring employs the study of heat transfer characteristics in the soils, as the temperature distribution in earth-filled structures can be influenced by the presence of seepage. Thus, continuous temperature measurements can allow detection of seepage flows. With the recent advances in optical fiber temperature sensor technology, accurate and fast temperature measurements, with relatively high spatial resolution, have been made possible using optical fiber distributed temperature sensors (DTSs). As with any sensor system, to obtain a precise temperature, the DTS measurements need to be calibrated. DTS systems automatically calibrate the measurements using an internal thermometer and reference section. Additionally, manual calibration techniques have been developed which are discussed in this paper. The temperature data do not provide any direct information about the seepage, and this requires further processing and analysis. Several methods have been developed to interpret the temperature data for the localization of the seepage and in some cases to estimate the seepage quantity. An efficient DTS application in seepage monitoring strongly depends on the following factors: installation approach, calibration technique, along with temperature data interpretation and post-processing. This paper reviews the different techniques for calibration of DTS measurements as well as the methods of interpretation of the temperature data.

• Language: English
• Keywords: hydrotechnics, optical fiber DTS, temperature, seepage, calibration, data interpretation
• Work type: Article
• Typology: 1.02 - Review Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 23 str.
• Numbering: Vol. 20, iss. 19, art. 5696
• PID: 20.500.12556/RUL-125103
• UDC: 626/627
• ISSN on article: 1424-8220
• DOI: 10.3390/s20195696
• COBISS.SI-ID: 51392771
• Publication date in RUL: 04.03.2021

Record is a part of a journal

• Title: Sensors
• Shortened title: Sensors
• Publisher: MDPI
• ISSN: 1424-8220
• COBISS.SI-ID: 10176278

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 06.10.2020

Secondary language

• Language: Slovenian
• Keywords: hidrotehnika, DTS, temperatura, precejanje, kalibracija

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0180
• Name: Vodarstvo in geotehnika: orodja in metode za analize in simulacije procesov ter razvoj tehnologij

• Funder: Other - Other funder or multiple funders
• Funding programme: Czech Republic
• Project number: FAST-S-19-5714
• Name: Probability assessment of internal instability in earth structures and in hydraulic structures