TY - CHAP A1 - Maierhofer, Christiane A1 - Kohl, Christoph A1 - Wöstmann, Jens ED - Maierhofer, C. ED - Reinhardt, H.-W. ED - Dobmann, G. T1 - Combining the results of various non-destructive evaluation techniques for reinforced concrete: data fusion KW - Non-destructive testing KW - Concrete KW - Data fusion KW - Radar KW - Ultrasonic techniques PY - 2010 SN - 978-1-84569-950-5 VL - 2 IS - Chapter 5 SP - 95 EP - 107 PB - Woodhead Publ. AN - OPUS4-22607 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Streicher, Doreen A1 - Krause, Martin A1 - Kohl, Christoph A1 - Schickert, M. A1 - Kroggel, O. A1 - Müller, W. T1 - Parameters for the Quantitative Assessment of Ulrasonic Imaging for Concrete Elements N2 - Ultrasonic investigation is an established non-destructive testing method for detection of defects and material characterisation. In the last years scanning ultrasonic echo methods were developed especially for the application in civil engineering. The different scanning ultrasonic echo methods are modified with respect to the type of the transducer applied, the number and the arrangement of transducers and the frequency used. Also different algorithms are used to analyse the measured data, for instance SAFT (Synthetic Aperture Focusing Technique) reconstruction. The results are typically presented as B- and C-scans, obtained from raw data or the SAFT reconstructed data. Since 2001 several German research institutes co-operate within the scope of the research initiative Non-destructive Evaluation of Concrete Structures Using Acoustic and Electromagnetic Echo-Methods (FOR 384) supported by the Deutsche Forschungsgemeinschaft (DFG). One of the tasks is to investigate these ultrasonic echo methods for special applications like the detection of cavities in concrete structures or faults in tendon ducts. Concrete test specimens with intentional faults have been manufactured and investigated. Parameters were defined to assess the results more objectively. Currently three parameters -signal/noise-ratio, lateral edge resolution and uniformity- are considered. For the first time results of different working groups on the same imaged objects are compared quantitatively. It should help to get more knowledge about the ultrasonic inspection of typical faults in civil engineering structures. T2 - 6th International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) CY - Berlin, Germany DA - 2003-09-16 PY - 2003 UR - http://www.ndt.net/article/ndtce03/papers/p050/p050.htm SN - 3-931381-49-8 SP - 1(?) EP - 12(?) PB - DGZfP CY - Berlin AN - OPUS4-2751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Mayer, K. A1 - Wöstmann, Jens A1 - Wiggenhauser, Herbert T1 - 3D-Visualisation of NDT-Data using Data Fusion Technique N2 - Non-destructive testing (NDT) of concrete structures is performed using pulse-echo methods. According to the type of the applied waves it can be classified as acoustic (Impact-Echo, Ultrasonics) and electromagnetic methods (Radar). The results are visualised through different imaging processes. This work is performed in the frame of a research project promoted by Deutsche Forschungsgemeinschaft (FOR384).The objective of data fusion is to use the complementary information of the different methods. Radar can detect metallic reflectors in concrete (metallic ducts and concrete reinforcement) very well. This method is not able to locate defects behind these reflectors (injecting defects, defects behind close concrete reinforcement), because the electromagnetic waves are completely reflected at metals. The acoustic methods are able to compensate this deficit i.e. acoustic waves can penetrate through metal. But acoustic waves in the ultrasonic range are completely reflected by air layers. Air layers have smaller influence on radar propagation, so that both methods complement each other.In order to be able to combine the NDT-data from several methods records at the same volume, the different data setsmodes of signals must be adapted. The ultrasonic and radar data have to be reconstructed with programs based on the Synthetic Aperture Focusing Technique (SAFT) before data fusion. Subsequently, a conversion of the data into a uniform format has to be carried out. This is a prerequisite in order to keep the data exchange between the project partners as simple as possible. After the data sets are imported and transferred into a common reference system, they can be processed with operations according to the purpose of the investigation. Results, which have been achieved in concrete test specimen with radar and ultrasonics, will be presented and will show the feasibility of the data fusion method. T2 - 6th International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) CY - Berlin, Germany DA - 2003-09-16 KW - Radar KW - Ultrasonic KW - Data Fusion PY - 2003 UR - http://www.ndt.net/article/ndtce03/papers/v023/v023.htm SN - 3-931381-49-8 SP - 1 EP - 11(?) PB - DGZfP CY - Berlin AN - OPUS4-3053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kohl, Christoph A1 - Maierhofer, Christiane A1 - Krause, Martin A1 - Streicher, Doreen A1 - Wiggenhauser, Herbert ED - Mazal, P. T1 - Data fusion of complementary NDT methods applied in civil engineering T2 - 2nd International Workshop of NDT Experts CY - Prague, Czech Republic DA - 2003-10-06 KW - Non-destructive testing in civil engineering KW - Data fusion KW - Radar KW - Ultrasonics KW - Concrete PY - 2003 SN - 80-2142475-3 SP - 1 EP - 11(?) PB - Univ. of Technology CY - Brno AN - OPUS4-3054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mayer, K. A1 - Zimmer, A. A1 - Langenberg, K. J. A1 - Kohl, Christoph A1 - Maierhofer, Christiane T1 - Non-Destructive Evaluation of Embedded Structures in Concrete - Modeling and Imaging N2 - We concentrate on appropriate algorithmic processing of microwave Ground Penetrating Radar (GPR) data obtained from concrete specimens containing tendon ducts below steel reinforcement bars either via simulations or via experiments. The goal is to understand the physical phenomena of electromagnetic wave propagation and scattering in detail in order to optimize imaging algorithms like SAFT (Synthetic Aperture Focusing Technique as the NDT version of SAR) in its 3D diffraction tomographic FT-SAFT formulation (Fourier-Transform-SAFT). Therefore we start with the simulation of a "simple" specimen and switch to a more realistic one in order to check whether simulation and experiment can give comparable results. Basically, this could be confirmed, but, nevertheless, various parametric studies will still have to be performed in the future. T2 - 6th International Symposium Non-Destructive Testing in Civil Engineering (NDT-CE) CY - Berlin, Germany DA - 2003-09-16 KW - Non-destructive testing in civil engineering KW - Radar KW - Modelling KW - SAFT KW - SAR PY - 2003 UR - http://www.ndt.net/article/ndtce03/papers/v022/v022.htm SN - 3-931381-49-8 VL - 85-CD PB - DGZfP CY - Berlin AN - OPUS4-3159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kohl, Christoph T1 - 3D-Visualisation of NDT-Data using Data Fusion Technique T2 - International Symposium Non-Destructive Testing in Civil Engineering 2003 (NDT-CE 2003) CY - Berlin, Germany DA - 2003-09-16 PY - 2003 AN - OPUS4-3255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kohl, Christoph T1 - Datenfusion komplementärer Impuls-Echo Verfahren zur zerstörungsfreien Untersuchung von Betonbauteilen T2 - DACH-Jahrestagung 2004: ZfP in Forschung, Entwicklung und Anwendung CY - Salzburg, Austria DA - 2004-05-17 PY - 2004 AN - OPUS4-4566 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Mayer, K. A1 - Wöstmann, Jens A1 - Wiggenhauser, Herbert T1 - 3D-visualisation of NDT data using a data fusion technique KW - Non-destructive testing KW - Radar KW - Ultrasonic KW - Data fusion KW - SAFT PY - 2003 SN - 0007-1137 VL - 45 IS - 12 SP - 800 EP - 808 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-4585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Wöstmann, Jens A1 - Wiggenhauser, Herbert T1 - Datenfusion komplementärer Impuls-Echo Verfahren zur zerstörungsfreien Untersuchung von Betonbauteilen T2 - Jahrestagung Zerstörungsfreie Materialprüfung 2004 CY - Salzburg, Österreich DA - 2004-05-17 KW - Zerstörungsfreie Prüfung im Bauwesen KW - Radar KW - Ultraschall KW - Impact-Echo KW - Datenfusion KW - SAFT PY - 2004 UR - http://www.ndt.net/article/dgzfp04/papers/p37/p37.htm SN - 3-931381-55-2 SP - 1 EP - 15(?) PB - DGZfP CY - Berlin AN - OPUS4-5603 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maierhofer, Christiane A1 - Kohl, Christoph A1 - Mayer, K. T1 - Radar in der DFG-Forschergruppe FOR384 T2 - DAfStb-Fachtagung 2005 "Zerstörungsfreie Prüfverfahren und Bauwerksdiagnose im Betonbau" CY - Berlin, Deutschland DA - 2005-03-10 KW - Zerstörungsfreie Prüfung im Bauwesen KW - Radar KW - Datenfusion KW - Bewehrung KW - Spannkanal KW - Hohlkastenbrücke PY - 2005 SP - A19 EP - A24 PB - BAM CY - Berlin AN - OPUS4-7208 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Gardei, André A1 - Kohl, Christoph A1 - Wiggenhauser, Herbert ED - Naus, D. J. T1 - Improvement and combination of echo methods for NDT of concrete elements T2 - 2nd International RILEM Workshop on Life Prediction and Aging Management of Concrete Structures CY - Paris, France DA - 2003-05-05 PY - 2003 SN - 2-912143-36-5 IS - 29 SP - 137 EP - 147 PB - RILEM Publications CY - Bagneux AN - OPUS4-2621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wiggenhauser, Herbert A1 - Gardei, André A1 - Kohl, Christoph A1 - Maierhofer, Christiane A1 - Krause, Martin A1 - Streicher, Doreen ED - Watanabe, E. ED - Frangopol, D. T1 - Development and Application of Echo-Methods for NDE of Post Tensioned Concrete Bridges T2 - 2nd International Conference on Bridge Maintenance, Safety and Management CY - Kyoto, Japan DA - 2004-10-19 KW - ZfPBau KW - Spannbetonbrücken KW - Ultraschall Echo KW - Impact-Echo KW - Impuls Radar PY - 2004 SN - 90-5809-680-7 PB - Balkema CY - Leiden AN - OPUS4-4739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maierhofer, Christiane A1 - Krause, Martin A1 - Mielentz, Frank A1 - Streicher, Doreen A1 - Milmann, Boris A1 - Gardei, André A1 - Kohl, Christoph A1 - Wiggenhauser, Herbert T1 - Complementary application of radar, impact-echo and ultrasonics for testing concrete structures and metallic tendon ducts T2 - 83rd Annual Meeting Transportation Research Board of the National Academies CY - Washington, D. C., USA DA - 2004-01-11 KW - Non-destructive testing KW - Tendon duct KW - Concrete bridge KW - Radar KW - Ultrasonic KW - Impact-echo PY - 2004 SP - 18 pages CY - Washington AN - OPUS4-4909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kohl, Christoph T1 - Data Fusion of Complementary NDT Methods Applied in Civil Engineering T2 - International Symposium Non-Destructive Testing in Progress II CY - Prague, Czech Republic DA - 2003-10-06 PY - 2003 AN - OPUS4-3837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohl, Christoph A1 - Streicher, Doreen T1 - Results of reconstructed and fused NDT-data measured in the laboratory and on-site at bridges N2 - Non-destructive testing (NDT) of concrete structures plays an increasing role in civil engineering. This paper presents the results of measurements carried out in the laboratory at BAM and on-site at several bridges using reconstructed and fused radar and ultrasonic echo data sets. In this context different scanning systems, developed for the on-site application of NDT-methods (e.g. reinforced concrete bridges) are introduced. The main object was the demonstration of the improved effectiveness of radar and ultrasonic pulse echo technique due to the automated measurements and the application of new software for the data processing and data visualisation. The results of these measurements show the high potential of reconstruction and data fusion for the improvement and simplification of the interpretability of large data sets measured with impulse-echo methods. KW - Non-destructive testing KW - Prestressed concrete bridges KW - Radar KW - Ultrasonic pulse echo technique KW - Data fusion KW - Scanning system PY - 2006 DO - https://doi.org/10.1016/j.cemconcomp.2006.02.005 SN - 0958-9465 SN - 1873-393X VL - 28 IS - 4 SP - 402 EP - 413 PB - Elsevier CY - Barking, Essex AN - OPUS4-12307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Streicher, Doreen A1 - Kohl, Christoph A1 - Wiggenhauser, Herbert A1 - Petz, J. T1 - Assessment of post tensioned box girder bridges applying automated non-destructive testing methods T2 - 85th TRB Annual Meeting CY - Washington D.C., USA DA - 2006-01-22 KW - Automatisierte ZfPBau-Verfahren KW - Radar KW - Ultraschallecho KW - Impact-Echo KW - Spannbetonbrücken PY - 2006 SP - 1 EP - 13(?) PB - TRB CY - Washington, D.C. AN - OPUS4-12238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Streicher, Doreen A1 - Kohl, Christoph A1 - Wiggenhauser, Herbert T1 - Assessment of post tensioned concrete bridges applying automated non-destructive testing systems T2 - 1st Munich Bridge Assessment Conference (MBAC 2005) CY - Munich, Germany DA - 2005-06-20 KW - Automatisierte ZfPBau-Verfahren KW - Radar KW - Ultraschallecho KW - Impact-Echo KW - Spannbetonbrücken KW - Scannersysteme KW - Bridge investigations KW - Ultrasonic echo KW - Data fusion KW - Scanning system PY - 2005 SP - 13 pages PB - University of the German Armed Forces CY - München AN - OPUS4-11077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohl, Christoph A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Wöstmann, Jens T1 - 2D- and 3D-visualisation of NDT-data using data fusion technique N2 - Non-destructive testing (NDT) of concrete structures is performed using pulse-echo methods. According to the type of the applied waves it can be classified as acoustic (Impact-Echo, Ultrasonics) and electromagnetic methods (Radar). The results are visualised through different imaging processes. This work is performed in the frame of a research project promoted by Deutsche Forschungsgemeinschaft (FOR384). The objective of data fusion is to use the complementary information of the different methods. Radar can detect metallic reflectors in concrete (metallic ducts and concrete reinforcement) very well. This method is not able to locate defects behind these reflectors (injecting defects, defects behind close concrete reinforcement), because the electromagnetic waves are completely reflected at metals. The acoustic methods are able to compensate this deficit i.e. Acoustic waves can penetrate through metal. But acoustic waves in the ultrasonic range are completely reflected by air layers. Air layers have smaller influence on radar propagation, so that both methods complement each other. In order to be able to combine the NDT-data from several methods records at the same volume, the different data setsmodes of signals must be adapted. The ultrasonic and radar data have to be reconstructed with programs based on the Synthetic Aperture Focusing Technique (SAFT) before data fusion. Subsequently, a conversion of the data into a uniform format has to be carried out. This is a prerequisite in order to keep the data exchange between the project partners as simple as possible. After the data sets are imported and transferred into a common reference system, they can be processed with operations according to the purpose of the investigation. Results, which have been achieved in concrete test specimen with radar and ultrasonics, will be presented and will show the feasibility of the data fusion method. KW - Non-destructive testing KW - Radar KW - Ultrasonic KW - Impact-echo KW - Data fusion KW - SAFT PY - 2005 SN - 1359-5997 SN - 1871-6873 VL - 38 IS - 283 SP - 817 EP - 826 PB - Springer CY - Dordrecht AN - OPUS4-11591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Streicher, Doreen A1 - Kohl, Christoph A1 - Wiggenhauser, Herbert A1 - Taffe, Alexander T1 - Automatisierte zerstörungsfreie Zustandsuntersuchungen von Brückenbauwerken N2 - Zerstörungsfreie Prüfverfahren im Bauwesen werden zunehmend für großflächige und detaillierte Zustandsuntersuchungen von Bauwerken angewendet. Für gezielte Untersuchungen von spanngliedführenden Bereichen mit einem Schadensverdacht in Spannbetonbauwerken eignen sich die Prüfverfahren Ultraschallecho, Impakt-Echo und Radar. Eine nennenswerte Verbesserung der Ergebnisse und deren Interpretation wurde in den letzten Jahren durch die weiterführende Datenauswertung mit Hilfe von 3D-Rekonstruktionsrechnungen und der Kombination von Meßdaten durch Datenfusion erreicht. Die Anwendung der Verfahren mit automatisierter Meßwerterfassung wird für Fahrbahnplatten und Hohlkastenstege dargestellt und diskutiert. Ergebnisse einer Meßunsicherheitsbetrachtung und deren Bedeutung werden an einer Fundamentplatte aufgezeigt. Translated Abstract Automated Non-Destructive Assessment of Bridges Non-destructive test methods in civil engineering are increasingly used for large-area investigations of structures. The test methods ultrasonic-echo, impact-echo and radar are well suited for detailed investigations of pre-stressed areas at pt-concrete structures. A significant improvement of the results and their interpretations has been achieved in recent years using advanced data analysis procedures such as 3D-reconstructions and the fusion of data. The automated application of the methods has been carried out successfully at decks and webs of pre-stressed box girder bridges. The achieved results are discussed in detail. The measurement uncertainty and its importance for the results are presented considering as example a foundation slab. KW - Zerstörungsfreie Prüfung KW - Brückenprüfung KW - Ultraschallecho KW - Radar KW - Automatisierung KW - Brückenscanner KW - Validierung KW - SAFT KW - Rekonstruktion PY - 2006 DO - https://doi.org/10.1002/best.200600479 SN - 0005-9900 SN - 1437-1006 VL - 101 IS - 5 SP - 330 EP - 342 PB - Ernst CY - Berlin AN - OPUS4-14036 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mayer, K. A1 - Langenberg, K.-J. A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Milmann, Boris A1 - Kohl, Christoph T1 - Characterization of ultrasonic and radar reflector types in concrete by phase evaluation of the signal and the reconstructed image T2 - 9th European Conference on NDT CY - Berlin, Germany DA - 2006-09-25 KW - NDT-CE KW - Ultrasonic echo KW - Radar KW - Phase evaluation KW - Modeling of wave propagation KW - Reconstruction calculation PY - 2006 SN - 3-931381-86-2 SP - 1 EP - 8(?) PB - European Federation for Non-Destructive Testing CY - Berlin AN - OPUS4-14225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -