TY - CONF A1 - Hong, Shuxian A1 - Lai Wai-Lok, Wallace A1 - Helmerich, Rosemarie A1 - Milmann, Boris ED - Biondini, F. ED - Frangopol, D.M. T1 - NDT-based monitoring of accelerated steel corrosion in concrete T2 - IABMAS 2012 - 6th International conference on bridge maintenance, safety and management CY - Stresa, Lake Maggiore, Italy DA - 2012-07-08 KW - Concrete KW - Reinforcement corrosion KW - Nondestructive testing KW - Ground penetration radar KW - Ultrasonic echo PY - 2012 SN - 978-0-415-62124-3 SN - 978-0-203-10338-8 SP - 1 EP - 8(?) PB - CRC Press CY - London, UK AN - OPUS4-29581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hong, Shuxian A1 - Lai Wai-Lok, Wallace A1 - Wilsch, Gerd A1 - Helmerich, Rosemarie A1 - Helmerich, R. A1 - Günther, Tobias A1 - Wiggenhauser, Herbert T1 - Periodic mapping of reinforcement corrosion in intrusive chloride contaminated concrete with GPR N2 - This paper presents an experimental effort for developing a novel reinforcement corrosion monitoring technique based on Ground Penetrating Radar (GPR). Experiments were carried out to periodically monitor the accelerated reinforcement corrosion process with GPR. The data were processed in both time and time–frequency domains to investigate the tendencies of GPR signal attribute changes related with corrosion, moisture and chloride contamination. Data processing methods were proposed to visualize the reinforcement corrosion and chloride distribution with target specified signal attribute mapping. Half-Cell Potential (HCP) and Laser-Induced Breakdown Spectroscopy (LIBS) methods were employed to verify the GPR observations. KW - Reinforcement corrosion KW - Chloride contamination KW - Periodic monitoring KW - Ground penetrating radar PY - 2014 U6 - https://doi.org/10.1016/j.conbuildmat.2014.06.019 SN - 0950-0618 VL - 66 SP - 671 EP - 684 PB - Elsevier Science CY - Amsterdam AN - OPUS4-31397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hong, Shuxian A1 - Wiggenhauser, Herbert A1 - Helmerich, Rosemarie A1 - Peng, B.D. A1 - Xing, D. F. T1 - Long-term monitoring of reinforcement corrosion in concrete using ground penetrating radar N2 - A new method for periodically monitoring reinforcement corrosion in concrete with Ground-Penetrating Radar (GPR) is proposed and a ten-year long-term corrosion periodic monitoring experiment is reported. GPR historical data was taken in different years, under different conditions. In order to align and normalize the obtained images properly prior to effectively performing any automatic defect detection, image registration techniques based on mutual-information are employed, and a new signal processing scheme is proposed for normalizing the intensity of GPR images. Then, the processed image results can be used to compare and find out the change of GPR detection due to corrosion. KW - Steel reinforced concrete KW - Atmospheric corrosion KW - Pitting corrosion PY - 2017 U6 - https://doi.org/10.1016/j.corsci.2016.11.003 SN - 0010-938X VL - 114 SP - 123 EP - 132 PB - Elsevier Ltd. AN - OPUS4-38346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hong, Shuxian A1 - Lai, W.-L. A1 - Helmerich, Rosemarie T1 - Experimental monitoring of chloride-induced reinforcement corrosion and chloride contamination in concrete with ground-penetrating radar N2 - In this article, we present a laboratory experiment to monitor the accelerated corrosion in concrete using ground-penetrating radar (GPR). Four concrete test specimens were cast with rebars of different size and placed at different depths. The lifetime decades of reinforcement corrosion process were accelerated into 18 days by using the impress current technique. The electrochemical corrosion process was periodically monitored with GPR. Two control specimens were also prepared to investigate the influence of chloride contamination on GPR signal. The measured data were analysed both in time and frequency domains. In time domain, the peak-to-peak amplitude of a wave reflected by a rebar was calculated to investigate the relationship between an increase in signal amplitude and the degree of corrosion. In frequency domain, the time–frequency representations of the signal were computed by using S-transform. The results show that reinforce corrosion increased the amplitude of reflected signal in time domain but did not change the peak frequency in frequency domain while chloride contamination attenuates the signal to smaller amplitude and lower peak frequency. Based on the results, a novel process is finally proposed for GPR-based corrosion detection. KW - Non-destructive KW - Reinforcement corrosion KW - GPR KW - Chloride KW - Moisture KW - S-transform PY - 2015 U6 - https://doi.org/10.1080/15732479.2013.879321 SN - 1573-2479 VL - 11 IS - 1 SP - 15 EP - 26 PB - Taylor & Francis CY - London [u.a.] AN - OPUS4-33085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -