TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus A1 - Krebber, Katerina T1 - Characterizing vibration response of fiber cables for distributed acoustic sensing T2 - Proceedings 27th International Conference on Optical Fiber Sensors N2 - The vibration responses of two fiber cables are characterized up to 16 kHz and compared with a standard tight-buffered 900 um fiber. The response of the cables is suppressed due to the cable protection T2 - 27th International Conference on Optical Fiber Sensors (OFS-27) CY - Alexandria, VA, USA DA - 29.08.2022 KW - Response characterization KW - Distributed fiber sensing KW - Acoustic sensing PY - 2022 SP - 1 EP - 4 PB - Optica CY - Washington D.C., USA AN - OPUS4-56096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus A1 - Weege, S. A1 - Roske, T. A1 - Krebber, Katerina T1 - Leakage detection at a borehole simulator using distributed acoustic sensing T2 - Proceedings 27th International Conference on Optical Fiber Sensors N2 - A distributed acoustic sensing system is used to detect the leakage in a borehole simulator by measuring the leakage induced vibration. The leakage location can be clearly determined by frequency spectrum analysis. T2 - 27th International Conference on Optical Fiber Sensors (OFS-27) CY - Alexandria, VA, USA DA - 29.08.2022 KW - Leakage detection KW - Structural health monitoring KW - Distributed fiber sensing KW - Distributed acoustic sensing PY - 2022 SP - 1 EP - 4 PB - Optica CY - Washington D.C., USA AN - OPUS4-56097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus A1 - Weege, S. A1 - Roske, T. A1 - Krebber, Katerina T1 - Leakage detection at a borehole simulator using distributed acoustic sensing N2 - A distributed acoustic sensing system is used to detect the leakage in a borehole simulator by measuring the leakage induced vibration. The leakage location can be clearly determined by frequency spectrum analysis. T2 - 27th International Conference on Optical Fiber Sensors (OFS-27) CY - Alexandria, VA, USA DA - 29.08.2022 KW - Structural health monitoring KW - Distributed fiber sensing KW - Distributed acoustic sensing KW - Leakage detection PY - 2022 AN - OPUS4-56098 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus A1 - Krebber, Katerina T1 - Characterizing vibration response of fiber cables for distributed acoustic sensing N2 - The vibration responses of two fiber cables are characterized up to 16 kHz and compared with a standard tight-buffered 900 um fiber. The response of the cables is suppressed due to the cable protection. T2 - 27th International Conference on Optical Fiber Sensors (OFS-27) CY - Alexandria, VA, USA DA - 29.08.2022 KW - Distributed fiber sensing KW - Acoustic sensing KW - Response characterization PY - 2022 AN - OPUS4-56099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Xin A1 - Chruscicki, Sebastian A1 - Schukar, Marcus A1 - Münzenberger, Sven A1 - Krebber, Katerina T1 - Application of Intensity-Based Coherent Optical Time Domain Reflectometry to Bridge Monitoring JF - Sensors N2 - Although distributed fiber sensing techniques have been widely used in structural health monitoring, the measurement results of bridge monitoring, particularly under destructive testing, have rarely been reported. To the best of our knowledge, this paper is the first report of distributed vibration measurement results, which we obtained during a three-day destructive test on an abolished bridge. A coherent optical time domain reflectometry (COTDR) was used to acquire the vibration information while the bridge was being sawed. The obtained signal was analyzed in time and frequency domain. Some characteristics of the sawing-induced vibration were retrieved by the short-time Fourier transform; the vibration exhibited several high frequency components within the measured range up to 20 kHz and all the components appeared in the same time slot. Some unexpected signals were also detected. Thorough analysis showed that they are quite different from the sawing-induced vibration and are believed to originate from internal damage to the bridge (probably the occurrence of cracks). KW - Destructive testing KW - Structural health monitoring KW - Distributed fiber sensing KW - Distributed acoustic sensing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547451 DO - https://doi.org/10.3390/s22093434 VL - 22 IS - 9 SP - 3434 PB - MDPI AN - OPUS4-54745 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus A1 - Großwig, S. A1 - Weber, U. A1 - Krebber, Katerina T1 - Monitoring acoustic events in boreholes using wavelengthscanning coherent optical time domain reflectometry in multimode fiber T2 - EAGE GeoTech 2021 Second EAGE Workshop on Distributed Fibre Optic Sensing N2 - A distributed acoustic sensor (DAS) based on wavelength-scanning coherent optical time domain reflectometer (WS-COTDR) is tested in an underground gas storage based on a multimode fiber for the first time to the best of our knowledge. The WS-COTDR acquires the reflection spectrum by scanning the wavelength of the laser and uses the spectra to calibrate strain. It overcomes the fading problem which is common for all DAS systems, and possesses the advantage of simple configuration and low-cost. The working principle of the system is well explained and the measurement results are presented. Various artificial and natural acoustic events have been successfully detected by the WS-COTDR. Such a sensor demonstrates several advantages over the traditional DAS systems, so it is supposed to be widely used in the oil and gas industry. T2 - EAGE GeoTech 2021 CY - Online meeting DA - 01.03.2021 KW - Borehole monitoring KW - Distributed fiber sensing KW - Acoustic sensing PY - 2021 DO - https://doi.org/10.3997/2214-4609.202131010 SP - 1 EP - 5 AN - OPUS4-52152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -