TY - CONF A1 - Vlassopoulos, E. A1 - Caruso, S. A1 - Linnemann, Konrad A1 - Nasyrow, R. A1 - Gretter, R. A1 - Fongaro, L. A1 - Papaioannou, D. T1 - Mechanical integrity of spent nuclear fuel rods N2 - The properties of spent nuclear fuel (SNF) rods change significantly during their operation life in the reactor core. Further changes occur after their discharge mainly due to the heating-cooling processes and possible ageing associated with the cumulative effects of radioactive decay induce damage in the fuel. Such changes may affect the response of the SNF rods to mechanical solicitations corresponding to normal and accidental conditions. Research activities at JRC-KARLSRUHE aim at assessing the integrity of SNF rods and processes which might affect their mechanical properties during their interim storage, transport or other handling operations. JRC Hot Cell facilities have been fully adapted to fulfil the experimental goals. The number of experiments that can be performed, however, is limited and there is an acute need to model them, using this process to validate codes, to deeper understand and to extend the results gained at the JRC beyond the conditions that have been tested. For the experimental campaigns two devices for gravitational impact and 3-point bending tests were developed and installed in a hot cell. Segments of real SNF rods pressurized at their original pressures after discharge have been investigated. The setup is fully operational and new results are reported continuously. T2 - ANS Annual 2018 CY - Philadelphia, PA, USA DA - 17.06.2018 KW - Spent nuclear fuel KW - Mechanical testing KW - Hot cell testing PY - 2018 SP - 170 EP - 172 AN - OPUS4-44862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hoffmann, Dirk A1 - Niesel, Konrad A1 - Plagge, R. ED - Riederer, J. T1 - Relationship between pore structure and other physico-technical characteristics of stone T2 - 8th International Congress on Deterioration and Conservation of Stone CY - Berlin, Germany DA - 1996-09-30 KW - Stein KW - Porenstruktur KW - Eigenschaft, physikalisch-technisch PY - 1996 SN - 3-00-000779-2 VL - 1 SP - 461 EP - 472 CY - Berlin AN - OPUS4-645 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schäfer, A. A1 - Konrad, R. A1 - Kuhnigk, T. A1 - Kämpfer, P. A1 - Hertel, Horst A1 - König, H. T1 - Hemicellulose-degrading bacteria and yeasts from the termite gut PY - 1996 SN - 0021-8847 VL - 80 SP - 471 EP - 478 PB - Blackwell CY - Oxford AN - OPUS4-11826 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Rolle, Annette A1 - Wille, Frank A1 - Nasyrow, R. A1 - Papaioannou, D. A1 - Rondinella, V. A1 - Vlassopoulos, E. A1 - Pautz, A. T1 - Finite element modeling of spent fuel rod segments under bending loads N2 - Transport packages for spent nuclear fuel have to be assessed with respect to specific transport conditions which are defined in the regulations of the International Atomic Energy Agency. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of the fuel assemblies are important Inputs for the evaluation of the package capabilities under These conditions. Cracks or failures in the fuel rod cladding can cause the release of gas, volatiles or fuel particles into the cavity. The amount of substances in the cavity has to be considered in the assessment of the activity release and criticality safety. The mechanical analysis of the compound system formed by the fuel rod cladding and the spent fuel pellets is very difficult due to the limited knowledge of the material properties and the insufficient understanding of the interaction between pellets and cladding and between adjacent pellets. The variation of fuel assembly properties regarding cladding material, burn-up and the history of usage makes reliable predictions of the fuel rod behavior even harder. For a better understanding about the behavior of spent fuel rods, JRC and BAM have started a joint research project. In this context, JRC has developed a test device which allows quasi-static 3-point-bending test on fuel rod segments in the hot cell. The loads are applied with respect to the boundary conditions of the activity release assessment. This paper deals with the numerical calculation of a single fuel rod segment under bending load. The aim is to identify the governing mechanical parameters by the variation of constitutive assumptions, contact conditions, inner constraints, etc. This knowledge helps for the interpretation of the experimental results. Furthermore, the improved understanding about the behavior of the cladding-pellets system will be beneficial for the assessment of spent fuel transport conditions. T2 - SMIRT24 - 24th Conference on Structural Mechanics in Reactor Technology CY - Busan, Korea DA - 20.08.2017 KW - Finite element methods KW - Spent fuel assessment KW - Transport packages PY - 2017 SP - 1 EP - 8 AN - OPUS4-45316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Rolle, Annette A1 - Wille, Frank A1 - Nasyrow, R. A1 - Papaioannou, D. A1 - Vlassopoulos, E. A1 - Rondinella, V. T1 - Analysis of parameters affecting the bending behavior of spent fuel rods N2 - Transport packages for spent nuclear fuel have to be assessed with respect to specific transport conditions which are defined in the regulations of the International Atomic Energy Agency. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of the fuel assemblies are important inputs for the evaluation of the package capabilities under these conditions. Cracks or failures in the fuel rod cladding can cause the release of gas, volatiles or fuel particles into the cavity. The amount of substances in the cavity has to be considered in the assessment of the activity release and criticality safety. The mechanical analysis of the compound system formed by the fuel rod cladding and the spent fuel pellets is very difficult due to the limited knowledge of the material properties and the insufficient understanding of the interaction between pellets and cladding and between adjacent pellets. The variation of fuel assembly properties regarding cladding material, burn-up and the history of usage makes reliable predictions of the fuel rod behavior even harder. For a better understanding about the behavior of spent fuel rods, JRC-ITU and BAM have started a joint research project. In this context, JRC-ITU has developed a test device which allows quasi-static 3-point-bending test on fuel rod segments in the hot cell. The loads are applied with respect to the boundary conditions of the activity release assessment. This paper deals with the numerical calculation of a single fuel rod segment under bending load. The aim is to identify the governing mechanical parameters by the variation of constitutive assumptions, contact conditions, inner constraints, etc. This knowledge helps for the interpretation of the experimental results. Furthermore, the improved understanding about the behavior of the cladding-pellets system will be beneficial for the assessment of spent fuel transport conditions. T2 - PATRAM 2016 - 18th International symposium on the packaging and transportation of radioactive materials CY - Kobe, Japan DA - 18.09.2016 KW - Transport packages KW - Finite element methods KW - Spent fuel assessment PY - 2016 SP - Paper 2012, 1 AN - OPUS4-40000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nasyrow, R. A1 - Papaioannou, D. A1 - Rondinella, V. A1 - Vlassopoulos, E. A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Rolle, Annette A1 - Wille, Frank A1 - Caruso, St. T1 - Bending test device for mechanical integrity studies of spent nuclear fuel rods N2 - This paper presents data obtained from experiments performed using a bending test set-up developed at the Joint Research Centre (JRC) – Karlsruhe, for spent fuel segment testing. Adjustable sample holders, loading modes and other experimental conditions can be im- plemented in the experiments to study the effects of different deformation ranges up to cladding failure. The experimental set-up has been adapted to hot cell remote controlling and has a modular configuration, which allows manual and motor-driven loading option. The device has been calibrated on hydrogenated, unirradiated cladding tube segments filled with alumina pellets. The final application of present set-up is to test non-defueled spent fuel rod segments, pressurized to the original spent fuel rod pressure level. The range of applicability of this device, the scope of the experimental program and the first results from actual bending tests will be discussed. T2 - PATRAM 2016 - 18th International Symposium on the Packaging and Transportation of Radioactive Materials CY - Kobe, Japan DA - 18.09.2016 KW - Hot cell testing KW - Spent fuel assessment KW - Transport packages PY - 2016 SP - Paper 6023, 1 AN - OPUS4-40002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -