TY - CHAP A1 - Dengler, S. A1 - Schmidt, N. A1 - Luber, M. A1 - Fischer, J. A1 - Ziemann, Olaf A1 - Engelbrecht, Rainer A1 - Hangen, H. T1 - B8.3 Influence of Temperature on Distributed Strain Sensing with OTDR in Polymer Optical Fibers T2 - SMSI 2021 - Sensors and Instrumentation N2 - Strain in ground and earthworks can be measured by polymer optical fibers (POF) applied to geotextiles. We measure the increase of backscatter (IOB) in the fiber under strain using optical time domain reflectometry (OTDR). The effect of temperature on this measurement principle is investigated. The local backscatter changes by 0.003 dB/K for common ambient temperature. In addition it is shown, that temperature depended viscoelastic properties of the polymer does affect IOB. KW - optical time domain reflectometry, structural health monitoring, strain sensing, geotextiles, polymer optical fib Y1 - 2021 SN - 978-3-9819376-4-0 U6 - https://doi.org/10.5162/smsi2021/b8.3 SP - 155 EP - 156 PB - AMA Service GmbH, Von-Münchhausen-Str. 49, 31515 Wunstorf, Germany ER - TY - CHAP A1 - Engelbrecht, Rainer A1 - Dengler, S. A1 - Luber, M. A1 - Fischer, J. A1 - Hangen, H. T1 - SHM at Giant Mine Heaps by OTDR Sensing with Polymer Optical Fibers BT - Chances and Challenges from Field Campaigns T2 - Optical Fiber Sensors Conference 2020 Special Edition N2 - Results from field measurement campaigns for structural health monitoring (SHM) at giant mine heaps by optical time domain reflectometry (OTDR) in polymer optical fibers (POF) are presented. Polymer geogrids built for soil reinforcement are fitted with POF for strain sensing as part of a geosynthetic sealing system designed to protect the heap from infiltration of surface water. Strain is detected by a local increase of backscatter. Measurements on eight sensor lines have been performed over a time period of six months to monitor the system behavior and potential development of or cracks within the underlying base of a sealing system. Results show the usability of this technology for strain sensing and SHM in such a harsh environment. Challenges still exist in the quantitative evaluation of the fiber sensor data due to cross sensitivity to fiber bending and lateral pressure. Y1 - 2021 U6 - https://doi.org/10.1364/ofs.2020.th4.7 PB - Optica Publishing Group CY - Washington, D.C. ER -