TY - JOUR A1 - Steffens, H.-D. A1 - Müller, K.-N. A1 - Wittig, Günther T1 - Zerstörungsfreies Ermitteln der Schichtdicke thermisch gespritzter Überzüge PY - 1974 SN - 0025-5300 VL - 16 IS - 5 SP - 125 EP - 128 PB - Carl Hanser Verlag CY - München AN - OPUS4-8110 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chabrelie, A. A1 - Müller, Urs A1 - Scrivener, K.L. ED - Palomo, Á. ED - Zaragoza, A. ED - Agüí, J. C. L. T1 - Mechanisms of degradation of concrete by external sufate ions under laboratory and field conditions N2 - The durability of concrete is a major challenge for the construction, which devotes one third to one half of its annual investment to building maintenance. The lack of fieid data regarding concrete durability, especially in the case of exposure to Sulfate ions (“sulfate attack”) makes it dijficult to determine the appropriate fest methods andperformance criteria. Additionally, the increased use of sustainable blends (cement with mineral admixtures, typically slag from the iron industiy) suffers from a lack of experience regarding their long-term performance. Most results for sulfate resistance are derived from accelerated laboratoiy tests xvhere performance criteria are based only on macroscopic properties, especially expansion. To fill this gap and better widerstand the mechanisms of sulfate attack under real conditions, a parallel study of laboratoiy micro-concrete and fieid concrete samples under sulfate exposure was undertaken, focussing on microstructural changes in addition to the conventional macroscopic characterisation. Four exposure regimes were designed in the laboratoiy: full immersion (ponding), pH-control, semi-immersion and wet/diy cycles. Pure Portland blends and slag blends witli high level of slag replacement (70 wt.-%) were investigated. The exposure regime has been found to play a major role in the damage process. In ponding conditions, the damage process takes place in three stages characterised by a first period of induction, followed by surface damage thatfinally extends to the bulle of the material. Paradoxically, the w/c-ratio does not seem to have much impact on the ionic transport phenomena but might be more decisive in the microstructure mechanical strength against local stresses. The slag blends, considered as sulfate resistant in ponding exposure, revealed badperformances under wet/diy cycles. This beliaviour was attributed to poor proper physical resistance of the slag hydrates against diying. The fieid concretes selected for the comparison with the laboratoiy cases were partially buried in a sulfate-enriched soil in Argentina. A pure Portland blend and a slag blends with high level of slag replacement (80 wt.-%) were investigated. The submerged part of the samples could be compared to the laboratoiy ponding exposure, wliile the upper layer of the samples subjected to weathering could be compared to the laboratoiy wet/diy cycles exposure. The fieid obsen’ations tend to confirm the laboratoiy results and validate the fest settings. It has been underlined that a direct relationship between damage (e.g.; cracking/expansion) andphase assemblage was not evident. However, the study highlights that sulfate combination with the hydrates of the cement (e.g.; C-S-H) and with those of the slag would play a rote in the initiation of the expansion, which would be attributed to a swelling of the hydrates or to the precipitation offine ettringite after the Saturation level in sulfate of the hydrates has been reached. T2 - 13th International congress on the chemistry of cement - XIII ICCC CY - Madrid, Spain DA - 03.07.2011 KW - Sulfate attack KW - Exposure conditions KW - Concrete KW - Laboratory test KW - Field KW - Phase assemblage KW - Microstructure KW - XRD KW - SEM KW - SCM KW - Slag PY - 2011 SN - 978-84-7292-400-0 SP - 1 EP - 14 CY - Madrid AN - OPUS4-24810 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Renate A1 - Rudolphi, Reinald A1 - Liersch, K.W. T1 - Numerische Untersuchung der Wärmedämmung profilierter Dämmplatten für Wellplattendächer bei stationären Randbedingungen nach DIN 4108 PY - 1989 SN - 0341-0293 VL - 34 IS - 26 SP - 27 EP - 31 PB - Saint-Gobain Isover G+H CY - Ludwigshafen AN - OPUS4-1253 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Issever, A.S. A1 - Diederichs, G. A1 - Majumdar, S. A1 - Rogalla, P. A1 - Hamm, B.K. A1 - Lange, Axel A1 - Harwardt, Michael A1 - Hentschel, Manfred P. A1 - Müller, Bernd R. T1 - Analyser-based tomography images of cartilage N2 - Analyser-based imaging expands the performance of X-ray imaging by utilizing not only the absorption properties of X-rays but also the refraction and scatter rejection (extinction) properties. In this study, analyser-based computed tomography has been implemented on imaging an articular cartilage sample, depicting substructural variations, without overlay, at a pixel resolution of 3.6 µm. KW - Cartilage KW - Analyser-based imaging KW - Computed tomography PY - 2008 DO - https://doi.org/10.1107/S0909049508014829 SN - 0909-0495 SN - 1600-5775 VL - 15 IS - Part 5 SP - 525 EP - 527 PB - Blackwell Publishing CY - Oxford AN - OPUS4-17852 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auster, Jürgen A1 - Müller, Karsten A1 - Gründer, K.-P. T1 - Dynamic impact tests on materials & components of RAM packages - Advanced experimental and measurement methods N2 - In accident scenarios of transport packages or hypothetical crashes of containers in a storage facility or repository, the materials resistance against dynamic failure of the involved components is a deciding factor for package and container integrity during the handling, transport and storage for each type of radioactive material. For example, different dynamic impact tests on containers and components like lid sealing systems and specimens made of ductile cast iron and shock-absorbing materials are carried out by BAM. In order to perform dynamic impact tests with packages and its parts BAM operates two free-fall drop test facilities with maximum capacities of 200 t and 55 t, and a test bench for guided drop tests. This latter drop test machine enables a clearly specified component loading by a precisely positioned test object or drop weight and has been used recently for numerous investigations. The paper gives an overview of the wide range of experimental testing methods carried out within guided Impact and bending tests. Examples of methodological challenges are presented, especially such experimental analysis of dynamic impact conditions. In addition to known applied methods of dynamic, non-contact displacement measurements like high-speed 3-D surface deformation a recently patented 2-D tracking method is presented. By means of in-situ determination of fracture parameters with relevance to the materials stress intensity factor, the method has been successfully applied for a typical specimen geometry. Also shown are the possibility of detecting in-situ He-leakage rates on laterally impact loaded lid sealing systems as well as a method of acceleration sensor-temperature control under test conditions in the low temperature range. T2 - 18th International Symposium on the Packaging and Transportation of Radioactive Materials PATRAM 2019 CY - New Orleans, LA, USA DA - 04.08.2019 KW - Dynamic impact tests KW - Materials KW - RAM packages KW - Advanced experimental KW - Measurement methods PY - 2019 SP - Paper 1374, 1 EP - 10 AN - OPUS4-49067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -