TY - JOUR A1 - Wille, Frank A1 - Wolff, Dietmar A1 - Droste, Bernhard A1 - Völzke, Holger A1 - Baden, M. T1 - German approach and feedback on experience of transportability of SNF packages after interim storage N2 - In Germany, the concept of dry interim storage of spent fuel in dual purpose metal casks is implemented, currently for periods of up to 40 years. The casks being used have an approved package design in accordance with the international transport regulations. The license for dry storage is granted on the German Atomic Energy Act with respect to the recently revised 'Guidelines for dry interim storage of irradiated fuel assemblies and heat-generating radioactive waste in casks' by the German Waste management Commission. For transport on public routes between or after long term interim storage periods, it has to be ensured that the transport and storage casks fulfil the specifications of the transport approval or other sufficient properties, which satisfy the proofs for the compliance of the safety objectives at that time. In recent years, the validation period of transport approval certificates for manufactured, loaded and stored packages were discussed among authorities and applicants. A case dependent system of 3, 5 and 10 years was established. There are consequences for the safety cases in the Package Design Safety Report, including evaluation of long term behaviour of components and specific operating procedures of the package. The present research and knowledge concerning the long term behaviour of transport and storage cask components have to be consulted as well as experiences from interim cask storage operations. Challenges in the safety assessment are e.g. the behaviour of aged metal and elastomeric gaskets under IAEA test conditions to ensure that the results of drop tests can be transferred to the compliance of the safety objectives at the time of transport after the interim storage period. Assessment methods for the material compatibility, the behaviour of fuel assemblies and the aging behaviour of shielding parts are issues as well. This paper describes the state of the art technology in Germany, explains recent experience on transport preparation after interim storage and points out arising prospective challenges. KW - Radioactive material storage KW - Dry storage KW - Interim storage KW - Cask design KW - Radioactive material transport KW - Regulation KW - Operating procedures KW - Package KW - Safety KW - Storage KW - Transport KW - Lagerung KW - Spent fuel PY - 2014 U6 - https://doi.org/10.1179/1746510914Y.0000000064 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 25 IS - 2 SP - 55 EP - 59 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-33834 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheidemann, Robert A1 - Kasparek, Eva Maria A1 - Qiao, Linan A1 - Müller, Karsten A1 - Droste, Bernhard A1 - Völzke, Holger T1 - Dynamic penetration tests on shock absorbing damping concrete T2 - WM2014 Conference CY - Phoenix, Arizona, USA DA - 2014-03-02 KW - Drop test KW - Dynamic KW - Penetration KW - Damping concrete PY - 2014 SN - 978-0-9836186-3-8 SP - Paper 14166, 1 EP - 9 AN - OPUS4-31948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eisenacher, Germar A1 - Scheidemann, Robert A1 - Neumann, Martin A1 - Droste, Bernhard A1 - Völzke, Holger T1 - Dynamic crushing characteristics of spruce wood under large deformations N2 - An extensive series of large deformation crushing tests with spruce wood specimens was conducted. Material orientation, lateral constraint and loading rate were varied. Regarding material orientation, a reduction in the softening effect and the general force level was observed with a higher fiber-load angle. A comparison with characteristics gained by application of Hankinson's formula showed discrepancies in compression strength and the beginning of the hardening effect. Lateral constraint of the specimens caused a multiaxial stress state in the specimens, which was quantified with the applied measuring method. Further, a higher force level compared to specimens without lateral constraint and significant hardening effect at large deformations resulted. Thus, the influence of a multiaxial stress state on the force level could be determined. An increase in the loading rate led to higher force levels at any displacement value and material orientation. KW - Crushing test KW - Dynamic crushing characteristics KW - Spruce wood KW - Lateral constraint KW - Multiaxial stress state KW - Hankinson's formula PY - 2013 U6 - https://doi.org/10.1007/s00226-012-0508-5 SN - 0043-7719 SN - 1432-5225 VL - 47 IS - 2 SP - 369 EP - 380 PB - Springer CY - Berlin AN - OPUS4-27743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erhard, Anton A1 - Völzke, Holger A1 - Droste, Bernhard A1 - Wolff, Dietmar A1 - Wille, Frank T1 - Nuclear power plant waste management strategy in Germany T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 2013-08-18 PY - 2013 SP - 1 EP - 11(?) PB - Omnipress AN - OPUS4-30135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wolff, Dietmar A1 - Völzke, Holger A1 - Wille, Frank A1 - Droste, Bernhard T1 - Extended storage after long-term storage N2 - Existing spent nuclear fuel (SF) and high active waste (HAW) management policies and practices worldwide are the result of past presumptions that sufficient reprocessing and/or disposal capacity would be available in the near term. Consequently, in the past many countries have developed specific solutions for different periods of time due to their individual national nuclear policies. In Germany the concept of dry interim storage in dual purpose metal casks before disposal is being pursued for SF and HAW management and transport and storage licenses have been issued accordingly. The current operation licenses for existing storage facilities have been granted for a storage period of up to 40 years. This concept has demonstrated its suitability for over 20 years so far. Relevant safety requirements haven been assessed for the short-term as well as for the long-term for site-specific operational and accidental storage conditions. But in the meantime significant delays in the national repository siting procedure occured which will make extended storage periods necessary in the future. This paper describes the current situation in Germany with regard to dry cask storage and focuses on current perspectives considering regulatory, technical, and scientific aspects for storage license renewal. Since there is one case of a storage license limitation to only 20 years due to administrative reasons, first experience is currently gathered in case of an expiring storage license. Subsequent license options have been pursued intensively including the extension of the initial storage license as well as shipping all casks to another storage facility considering an extended storage period at that storage facility as well. All safety relevant aspects have to be reviewed on basis of the current state-of-the-art which might be different from the initial safety demonstrations. That includes new safety assessment standards as well as improved knowledge base. Major issues are e.g. improved accident scenario analyses, assessment methods, and consideration of aging effects from previous operation periods. Inspection programs with respect, e.g. to bolts and seals to verify leak-tightness and lid screw pre-stress have been initiated to demonstrate proper cask conditions for extended storage as well as transportation to another storage facility. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Extended storage KW - Long-term storage KW - Dual purpose cask PY - 2013 SP - Paper 184, 1 EP - 12 PB - Omnipress AN - OPUS4-30242 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wille, Frank A1 - Wolff, Dietmar A1 - Droste, Bernhard A1 - Völzke, Holger A1 - Baden, M. T1 - German approach and experience feedback of transport ability of SNF packages after interim storage N2 - In Germany the concept of dry interim storage of spent fuel in dual purpose metal casks is implemented, currently for periods of up to 40 years. The casks being used have an approved package design in accordance with the international transport regulations. The license for dry storage is granted on the German Atomic Energy Act with respect to the recently revised “Guidelines for dry interim storage of irradiated fuel assemblies and heat-generating radioactive waste in casks” by the German Waste management Commission (ESK). For transport on public routes between or after long term interim storage periods, it has to be ensured that the transport and storage casks fulfil the specifications of the transport approval or other sufficient properties which satisfy the proofs for the compliance of the safety objectives at that time. In recent years the validation period of transport approval certificates for manufactured, loaded and stored packages were discussed among authorities and applicants. A case dependant system of 3, 5 and 10 years was established. There are consequences for the safety cases in the Package Design Safety Report including evaluation of long term behavior of components and specific operating procedures of the package. Present research and knowledge concerning the long term behavior of transport and storage cask components have to be consulted as well as experiences from interim cask storage operations. Challenges in the safety assessment are e.g. the behavior of aged metal and elastomeric gaskets under IAEA test conditions to ensure that the results of drop tests can be transferred to the compliance of the safety objectives at the time of transport after the interim storage period. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Storage KW - Transport KW - Lagerung KW - Verpackung KW - Radioactive material PY - 2013 SP - 1 EP - 9 PB - Omnipress AN - OPUS4-30159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheidemann, Robert A1 - Kasparek, Eva Maria A1 - Müller, Karsten A1 - Droste, Bernhard A1 - Völzke, Holger T1 - Model-sized and full-scale dynamic penetration tests on damping concrete N2 - Mechanical loading conditions of transport and storage casks for radioactive materials in accidental scenarios are highly affected by the behavior of both: the impact limiters and the footing materials. To minimize potential damages during the handling of casks, a so called damping concrete is frequently used for the footings in interim nuclear facilities. It obtains its shock absorbing properties through admixing of polymer cells. For a comprehensive mechanical evaluation of casks, advanced material models are also needed for damping concrete. In order to characterize the mechanical properties and to develop numerical material models, penetration tests were carried out at different test facilities of BAM. The tests contain static and dynamic penetration tests on cubic specimen with an edge length of 100 mm as well as mortared specimen with a size of 240 x 240 x 50 cm³. Indenters with different geometries and diameters were used for these model-sized penetration tests. Subsequently a full-scale cylindrical cast-iron indenter with a diameter of 110 cm was dropped of 5 m height on a realistic damping concrete footing. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Drop test KW - Dynamic KW - Penetration KW - Damping concrete PY - 2013 SP - 1 EP - 10 PB - Omnipress AN - OPUS4-30233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wille, Frank A1 - Wolff, Dietmar A1 - Droste, Bernhard A1 - Völzke, Holger T1 - Requirements for transport packages after interim storage N2 - In Germany the concept of dry interim storage of spent fuel and vitrified high active waste in dual purpose metal casks is implemented (currently for periods of up to 40 years). The casks being used have an approved package design in accordance with the international transport regulations. The license for dry storage is granted on the German Atomic Energy Act with respect to the guidelines of the German Reactor Safety Commission for dry interim storage of spent fuel. Currently part of the assessment process of the cask design for transport on public routes is to evaluate the suitability of the used materials with respect to their properties and their compatibility for possible transport periods. For transport on public routes during or after long term interim storage periods, it has to be ensured that the transport and storage casks fulfill the specifications of the transport approval or other sufficient properties which satisfy the proofs for the compliance of the safety objectives at that time. This paper describes the state-of-the-art technology in Germany and points out arising prospective challenges and which related questions have to be answered in future. Present research and knowledge concerning the long term behavior of transport and storage cask components (such as gaskets and shielding components) have to be consulted as well as experiences from interim cask storage operations. Challenges in the safety assessment are therefore i.e. the behavior of aged metal and elastomeric gaskets under IAEA test conditions to ensure that the results of drop tests can be transferred to the compliance of the safety objectives at the time of transport after the interim storage period (aged package). Assessment methods for the material compatibility, the behavior of fuel assemblies and the aging behavior of shielding parts (e. g. influence of radiation) are further issues as well. T2 - 52nd INMM Annual meeting CY - Palm Desert, CA, USA DA - 17.07.2011 KW - Transport package design KW - Interim storage KW - Inspections KW - Log term behavior KW - Dual purpose casks PY - 2011 SP - 1 EP - 9 AN - OPUS4-24172 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Weber, Mike A1 - Qiao, Linan A1 - Droste, Bernhard A1 - Völzke, Holger T1 - Mechanical safety analyses of cast iron containers for the KONRAD repository N2 - Within the last years BAM has carried out numerous drop tests with prototype casks made of ductile cast iron onto targets according to the requirements for final disposal of non-heat generating waste in the German KONRAD repository. The results have shown that the target specifications in the acceptance criteria have to be defined more accurately to get reproducible test results with high precision. Hence, a suitable test stand foundation was developed with much effort. The integrity of the upper concrete layer of this target must be preserved during a test. Recently the geometrical properties of a tested cubic cast iron container led to a concentration of the impact forces beneath the container walls. The target was damaged strongly with the consequence of inadmissible reduction of cask stresses. For that reason the target construction was modified. However, the basic design was not changed. A prefabricated concrete slab was still joined by a mortar layer to the IAEA target of the BAM drop test facility. In the course of the optimization of the test stand foundation the concrete slab dimensions and the reinforcement were enlarged. During the drop test repetition the target kept intact. Additionally, the mechanical behavior of the cast iron container and the target was analyzed by finite element calculations. This improved target construction is suggested as a reference target for drop tests with casks whose mass and base area are covered by the container types VI or VII respectively according to the KONRAD repository acceptance criteria. The measurements during the drop tests with cast iron casks have provided the strains on the cask surface at selected positions. This allows the verification of finite element simulations of drop tests which show the stress distribution also inside the component. In September 2008 a drop test was carried out with a cylindrical cast iron cask containing an artificial material defect which was designed under consideration of critical stress states in the cask body. This drop test could demonstrate the safety against failure by fracture of a cask made of a special cast iron with reduced fracture toughness. T2 - PATRAM 2010 - 16th International symposium on the packaging and transport of radioactive materials CY - London, UK DA - 2010-10-03 KW - Ductile iron KW - Container design KW - Safety assessment KW - Fracture mechanics KW - Dynamic loading conditions PY - 2010 SP - 1 EP - 8 (Session T28 / Paper 220) AN - OPUS4-23844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sterthaus, Jens A1 - Ballheimer, Viktor A1 - Droste, Bernhard A1 - Koch, Frank A1 - Probst, Ulrich A1 - Völzke, Holger A1 - Wille, Frank T1 - Analysis of bolted flange joints for lids of packages for radioactive materials T2 - ASME 2009 Pressure vessels and piping conference CY - Prague, Czech Republic DA - 2009-07-26 KW - Bolted flange joints KW - FEA KW - Modelling of gaskets KW - Assessment of leak tightness KW - Results from experiments PY - 2009 SP - PVP2009-77284, 1-8 PB - American Society of Mechanical Engineers CY - New York AN - OPUS4-19786 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -