TY - CONF A1 - Hiller, Th. A1 - Costabel, S. A1 - Müller-Petke, M. A1 - Kruschwitz, Sabine T1 - Evaluation of different laboratory NMR devices in a tripartite round robin test N2 - Nuclear magnetic resonance (NMR) is a well established laboratory / borehole method to characterize the storage and transport properties of rocks due to its direct sensitivity to the corresponding pore fluid saturation (water or oil) and pore sizes. For petrophysical applications there are several different NMR laboratory devices commercially available varying over a wide range of e.g. magnetic field strength / frequency (2 MHz to 30 MHz), applicable measurement protocols (T1, T2, T1-T2, T2-D, etc.) and sample sizes (2.5 cm to 10 cm in diameter). In this work we present NMR measurements, layed out in a round robin like manner, on a set of 20 sandstone samples. We use three different NMR devices containing two standard setups with homogenous magnetic fields (LIAG and RWTH) and one single-sided setup with gradient field (BGR) to measure T1 and T2 relaxation data. In our evaluation we especially focus on the comparison of the individually inverted relaxation time distributions to quantify the differences arising from different laboratory setups. Diverging results can be deduced on the one hand to the inherit differences between homogeneous and gradient fields but on the other hand also due to quality differences between the two homogeneous setups. Additionally, we also examine the influence of the individually chosen inversion parameters (signal processing, distribution sampling points, error weighting, regularization, etc.) to establish a general standardized best practice recommendation for future petrophysical NMR laboratory measurements. T2 - 77. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Potsdam, Germany DA - 27.03.2017 KW - Nuclear Magnetic Resonance KW - Sandstone PY - 2017 AN - OPUS4-43244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine A1 - Halisch, M. A1 - Prinz, Carsten A1 - Weller, Andreas A1 - Müller-Petke, M. A1 - Dlugosch, R. T1 - Towards a better understanding of electrical relaxation N2 - Other than commonly assumed the relaxation times observed in the electrical low-frequency range (1 mHz – 40 kHz) of natural porous media like sandstones and tuff stones cannot be directly related to the dominant (modal) pore throat sizes, measured (e.g.) with mercury intrusion porosimetry (MIP). Working with a great variety of sandstones from very different origins and featuring great variations in textural and chemical compositions as well as in geometrical pore space properties, it was observed that particularly samples with narrow pore throats were characterized by long (low-frequency) relaxations. These, however, can (following the current theories) be rather explained by long “characteristic length scales” in these media or low diffusion coefficients along the electrical double layer. However, there is no straightforward way (or single approved method) of getting reliable numbers for properties such as the lengths of pore throats, the diameter and length of the wide pores and their respective distributions. Consequently we follow a multi-methodical approach and combine the benefits of MIP, micro-computed tomography (μ-CT) and nuclear magnetic resonance (NMR) to achieve much deeper insight due to the different resolutions and sensitivities to either pore constrictions (throats) or wide pores. This helps us to understand, whether the observed electrical relaxation phenomena actually depend on geometric length scales or rather on other properties such as chemical composition, clay content, clay type or cation exchange capacity. In this paper, we showcase selected results of a systematic study of a total of 16 sandstones and three tuffs. Findings and the particular advantage of the used method combination are discussed and shown in detail for a representative sample selection. T2 - Annual Symposium of the Society of Core Analysts (SCA) CY - Vienna, Austria DA - 28.08.2017 KW - Electrical relaxation KW - Complex resistivity KW - Spectral induced polarization KW - Nuclear magnetic resonance KW - Mercury intrusion porosimetry KW - Pore size distribution KW - Sandstone PY - 2017 VL - SCA2017-080 SP - 1 EP - 9 AN - OPUS4-42599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grohmann, Maria A1 - Müller, Sabine A1 - Niederleithinger, Ernst A1 - Sieber, S. T1 - Reverse time migration: introducing a new imaging technique for ultrasonic measurements in civil engineering N2 - Ultrasonic echo testing is widely used in non-destructive testing in civil engineering to investigate concrete structures, to measure thickness, and to locate and characterise built-in components or inhomogeneities. Currently, synthetic aperture focusing techniques are mostly used for imaging. These algorithms are highly developed but have some limitations. For example, it is not possible to image the lower boundary of built-in components like tendon ducts or vertical reflectors. We adopted reverse time migration for non-destructive testing in civil engineering in order to improve the imaging of complicated structures in concrete. By using the entire wavefield, including waves reflected more than once, there are fewer limitations compared to synthetic aperture focusing technique algorithms. As a drawback, the required computation is significantly higher than that for the techniques currently used. Simulations for polyamide and concrete structures showed the potential for non-destructive testing. The simulations were followed by experiments at a polyamide specimen. Here, having acquired almost noise-free measurement data to test the algorithm, we were able to determine the shape and size of boreholes with sufficient accuracy. After these successful tests, we performed experiments at a reinforced concrete foundation slab. We obtained information from the data by reverse time migration, which was not accessible by traditional imaging. The imaging of the location and structure of the lower boundary of the concrete foundation slab was improved. Furthermore, vertical reflectors inside the slab were imaged clearly, and more flaws were found. It has been shown that reverse time migration is a step forward in ultrasonic testing in civil engineering. KW - Ultrasonic echo technique KW - Reverse time migration PY - 2017 DO - https://doi.org/10.3997/1873-0604.2017006 SN - 1569-4445 SN - 1873-0604 VL - 15 IS - 3 SP - 242 EP - 258 PB - Wiley AN - OPUS4-41921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Sabine A1 - Niederleithinger, Ernst A1 - Krause, Martin A1 - Bohlen, T. T1 - Reverse time migration: A seismic imaging technique applied to ultrasound data T2 - NDE/NDT for highways and bridges - Structural materials technology (SMT) CY - New York, USA DA - 2010-08-16 KW - Ultraschall KW - Rekonstruktion KW - Migration PY - 2010 SN - 978-1-57117-211-2 SP - 554 EP - 559 CY - Columbus, OH, USA AN - OPUS4-22543 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grohmann, Maria A1 - Müller, Sabine A1 - Niederleithinger, Ernst T1 - Reverse time migration: Introduction of a new imaging technique for ultrasonic measurements in civil engineering N2 - Ultrasonic echo testing is widely used in non-destructive testing in civil engineering to investigate concrete structures, to measure thickness, and to locate and characterise built-in components or inhomogeneities. Currently, synthetic aperture focusing techniques are mostly used for imaging. These algorithms are highly developed but have some limitations. For example, it is not possible to image the lower boundary of built-in components like tendon ducts or vertical reflectors. We adopted reverse time migration for non-destructive testing in civil engineering in order to improve the imaging of complicated structures in concrete. By using the entire wavefield, including waves reflected more than once, there are fewer limitations compared to synthetic aperture focusing technique algorithms. As a drawback, the required computation is significantly higher than that for the techniques currently used. Simulations for polyamide and concrete structures showed the potential for non-destructive testing. The simulations were followed by experiments at a polyamide specimen. Here, having acquired almost noise-free measurement data to test the algorithm, we were able to determine the shape and size of boreholes with sufficient accuracy. After these successful tests, we performed experiments at a reinforced concrete foundation slab. We obtained information from the data by reverse time migration, which was not accessible by traditional imaging. The imaging of the location and structure of the lower boundary of the concrete foundation slab was improved. Furthermore, vertical reflectors inside the slab were imaged clearly, and more flaws were found. It has been shown that reverse time migration is a step forward in ultrasonic testing in civil engineering. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 KW - Ultrasound KW - Imaging KW - Reverse time migration KW - Reflection seismics KW - Concrete PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-345406 SN - 1435-4934 SP - 1 EP - 10 PB - Technische Universität Berlin / Bundesanstalt für Materialforschung und -prüfung AN - OPUS4-34540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Sabine A1 - Niederleithinger, Ernst A1 - Krause, Martin A1 - Bohlen, T. T1 - Anwendung der Reverse-Time Migration auf Ultraschallmessungen an Beton in der zerstörungsfreien Prüfung T2 - Tagung der Deutschen Geophysikalischen Gesellschaft 2011 CY - Cologne, Germany DA - 2011-02-21 PY - 2011 AN - OPUS4-23333 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Sabine A1 - Niederleithinger, Ernst T1 - Anwendung der Reverse Time Migration auf Ultraschall-Echo-Messungen in der zerstörungsfreien Prüfung im Bauwesen T2 - Jahrestagung der Deutschen Gesellschaft für Zerstörungsfreie Prüfung e.V. (DGZfP) CY - Potsdam, Germany DA - 2014-05-26 PY - 2014 AN - OPUS4-30920 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Sabine A1 - Niederleithinger, Ernst T1 - Anwendung der Reverse Time Migration auf Ultraschall-Echo-Messungen in der zerstörungsfreien Prüfung im Bauwesen T2 - 74. Jahrestagung der Deutschen Geophysikalischen Gesellschaft (DGG) CY - Karlsruhe, Germany DA - 2014-03-10 PY - 2014 AN - OPUS4-30432 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Sabine A1 - Niederleithinger, Ernst A1 - Krause, Martin A1 - Bohlen, T. T1 - Anwendung der Reverse-Time Migration auf Ultraschall-Echo-Messungen in der zerstörungsfreien Prüfung T2 - Jahrestagung der Deutschen Geophysikalischen Gesellschaft (DGG) CY - Hamburg, Germany DA - 2012-03-05 PY - 2012 AN - OPUS4-25609 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Sabine A1 - Niederleithinger, Ernst A1 - Bohlen, T. T1 - Reverse time migration: a seismic imaging technique applied to synthetic ultrasonic data N2 - Ultrasonic echo testing is a more and more frequently used technique in civil engineering to investigate concrete building elements, to measure thickness as well as to locate and characterise built-in components or inhomogeneities. Currently the Synthetic Aperture Focusing Technique (SAFT), which is closely related to Kirchhoff migration, is used in most cases for imaging. However, this method is known to have difficulties to image steeply dipping interfaces as well as lower boundaries of tubes, voids or similar objects. We have transferred a processing technique from geophysics, the Reverse Time Migration (RTM) method, to improve the imaging of complicated geometries. By using the information from wide angle reflections as well as from multiple events there are fewer limitations compared to SAFT. As a drawback the required computing power is significantly higher compared to the techniques currently used. Synthetic experiments have been performed on polyamide and concrete specimens to show the improvements compared to SAFT. We have been able to image vertical interfaces of step-like structures as well as the lower boundaries of circular objects. It has been shown that RTM is a step forward for ultrasonic testing in civil engineering. KW - Beton KW - Ultraschall KW - Concrete KW - Imaging KW - Ultrasonics KW - Reverse time migration PY - 2012 DO - https://doi.org/10.1155/2012/128465 SN - 1687-8868 SN - 1687-885X VL - 2012 IS - Article ID 128465 SP - 1 EP - 7 PB - Hindawi Publishing Corporation CY - New York, NY, USA AN - OPUS4-26295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Horn, Wolfgang A1 - Müller, B. A1 - Jann, Oliver A1 - Kasche, J. A1 - Däumling, C. A1 - Kalus, Sabine A1 - Brödner, Doris T1 - Emission and odour measurement of construction products evaluated using a german construction product evaluation scheme T2 - Indoor Air 2005 CY - Beijing, PR China DA - 2005-09-04 KW - AgBB-Scheme KW - Construction product KW - VOC emission KW - Odour KW - Chamber test PY - 2005 SN - 7-89494-830-6 IS - 2 SP - 2129 EP - 2133 PB - Tsinghua University Press CY - Beijing AN - OPUS4-10913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -