TY - CONF A1 - Neumann, Martin A1 - Günther, U. A1 - Ballheimer, Viktor A1 - Linnemann, Konrad A1 - Wille, Frank A1 - Droste, Bernhard T1 - Experiences by German authority with safety case approach for welding seams as part of SNF transport package containments N2 - Federal Institute for Materials Research and Testing (BAM) is the responsible authority for the assessment of mechanical and thermal safety as well as quality issues within the licensing procedure for transport casks for radioactive materials. The assessment includes a brittle fracture analysis of all relevant cask components. For cask bodies where a steel bottom is welded to a steel shell, specimens for testing of sufficient fracture resistance can normally not be extracted directly from the welding seam area of the cask. Therefore, a methodology has to be developed to ensure compliance with the safety Analysis considerations and the approved design specification. This paper describes such a methodology including brittle fracture analysis and de-termination of required material properties as well as aspects of quality assurance during manufacturing. T2 - RAMTRANSPORT 2012 - 9th International Conference on the Radioactive Materials Transport and Storage CY - London, UK DA - 22.05.2012 PY - 2012 IS - Session 4.2 RAM 18 SP - 1 EP - 6 AN - OPUS4-26344 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad A1 - Müller, Lars A1 - Schönfelder, Thorsten A1 - Komann, Steffen A1 - Wille, Frank T1 - Authority Experience during Design Approval Procedure for Packages Loaded with Special Encapsulations for Damaged Spent Nuclear Fuel N2 - The first German package design approval certificate for a dual purpose cask intended for loading with damaged spent nuclear fuel was issued recently. BAM as part of the competent authority system in Germany carried out a comprehensive assessment procedure with respect to the mechanical and thermal design, the release of radioactive material and the quality assurance aspects of manufacturing and operation. Packages for the transport and storage of radioactive material have been assessed by BAM for many years, thus the common assessment procedure is well-known and good practice. Up to now only SNF without defects or HLW with well-defined properties were designated for long-term Interim storage and transports afterwards. Due to Germany’s nuclear phase out all other kinds of spent nuclear fuel in particular damaged spent nuclear fuel shall be packed as well. Damaged spent nuclear fuel needs a tight closure with Special encapsulations and clearly defined properties in Germany. In addition, these encapsulations shall be long-term durable, because they are not accessible after loading in a packaging within periodical inspections. The main difference to Standard package components is that encapsulations with a permanent closure achieve their specified conditions not after manufacturing but only during operation, after loading and closing. To ensure compliance with the specific conditions, special measures for quality assurance are necessary during operation of each encapsulation, e.g. drying and sealing, which were assessed by BAM. The present paper gives an overview of the conducted assessment from BAM and point out the findings concerning to the special closure lid of the approved encapsulation, which is screwed and welded. A wide verification concept is necessary to show the specific tightness under transport conditions. Together with quality assurance measures during first operation steps these encapsulations with damaged spent nuclear fuel can be handled like standard fuel assemblies in approved package designs. T2 - International Conference on the Management of Spent Fuel from Nuclear Power Reactors CY - Vienna, Austria DA - 24.06.2019 KW - Transport package KW - Design approval KW - Spent nuclear fuel KW - Special encapsulation PY - 2019 SP - 1 EP - 9 AN - OPUS4-48749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad T1 - Authority Experience during Design Approval Procedure for Packages Loaded with Special Encapsulations for Damaged Spent Nuclear Fuel N2 - The first German package design approval certificate for a dual purpose cask intended for loading with damaged spent nuclear fuel was issued recently. BAM as part of the competent authority system in Germany carried out a comprehensive assessment procedure with respect to the mechanical and thermal design, the release of radioactive material and the quality assurance aspects of manufacturing and operation. Packages for the transport and storage of radioactive material have been assessed by BAM for many years, thus the common assessment procedure is well-known and good practice. Up to now only SNF without defects or HLW with well-defined properties were designated for long-term Interim storage and transports afterwards. Due to Germany’s nuclear phase out all other kinds of spent nuclear fuel in particular damaged spent nuclear fuel shall be packed as well. Damaged spent nuclear fuel needs a tight closure with Special encapsulations and clearly defined properties in Germany. In addition, these encapsulations shall be long-term durable, because they are not accessible after loading in a packaging within periodical inspections. The main difference to Standard package components is that encapsulations with a permanent closure achieve their specified conditions not after manufacturing but only during operation, after loading and closing. To ensure compliance with the specific conditions, special measures for quality assurance are necessary during operation of each encapsulation, e.g. drying and sealing, which were assessed by BAM. The present paper gives an overview of the conducted assessment from BAM and point out the findings concerning to the special closure lid of the approved encapsulation, which is screwed and welded. A wide verification concept is necessary to show the specific tightness under transport conditions. Together with quality assurance measures during first operation steps these encapsulations with damaged spent nuclear fuel can be handled like standard fuel assemblies in approved package designs. T2 - International Conference on the Management of Spent Fuel from Nuclear Power Reactors CY - Vienna, Austria DA - 24.06.2019 KW - Transport package KW - Spent nuclear fuel KW - Design approval KW - Special encapsulation PY - 2019 AN - OPUS4-48750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad T1 - Experimentelle und numerische Untersuchungen zur Bewertung der Integrität abgebrannter Brennelemente unter Transportbedingungen N2 - Packages for the transport of spent nuclear fuel shall meet the International Atomic Energy Agency regulations to ensure safety under different transport conditions. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of fuel assemblies are important inputs for the evaluation of the package capabilities under these conditions. The mechanical behavior of spent fuel assemblies shall be analyzed with regard to the assumptions which are used in the containment and criticality safety analysis. The package as a mechanical system is characterized by a complex set of interactions, e. g. between the fuel rods within the assembly as well as between the fuel assemblies, the basket, and the cask containment. This complexity makes it difficult to assume appropriate mechanical loads for the spent fuel inside the package. Another challenge is the assumption of material properties which represent the variation of the fuel rods regarding cladding material, burn-up and the operation history sufficiently. The objective of this paper is to give an overview about the current approaches and research for the evaluation of spent fuel behavior within the package design approval procedure. In this context, analytical, numerical and experimental results are discussed. The presented work is achieved within a collaboration of BAM with national and international partners. T2 - BGZ Fachworkshop Zwischenlagerung CY - Berlin, Germany DA - 22.10.2019 KW - Transportbehälter KW - Radioaktive Stoffe KW - Brennelementverhalten KW - FE-Berechnungen PY - 2019 AN - OPUS4-51174 LA - deu 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 - Vlassopoulos, Efstathios A1 - Papaioannou, Dimitrios T1 - Numerical Simulation of Spent Fuel Segments under Transport Loads N2 - Packages for the transport of spent nuclear fuel shall meet the International Atomic Energy Agency regulations to ensure safety under different transport conditions. The physical state of spent fuel and the fuel rod cladding as well as the geometric configuration of fuel assemblies are important inputs for the evaluation of package capabilities under these conditions. Generally, the mechanical behavior of high burn-up spent fuel assemblies under transport conditions shall be analyzed with regard to the assumptions which are used in the containment and criticality safety analysis. Considering the complexity of the interactions between the fuel rods as well as between the fuel assemblies, basket, and cask containment, the exact mechanical analysis of such phenomena is nearly impossible. The gaps in Information concerning the material properties of cladding and pellet behavior, especially for the high burn-up fuel, make the analysis more complicated additionally. As a result, enveloping analytical approaches are usually used by BAM within the safety assessment of packages approved for transport of spent nuclear fuel. To justify the safety margins of such approaches additional analyses are necessary. In this paper, numerical simulations of a spent fuel assembly Segment are presented. The segment modeled represents the part of a generalized BWR fuel assembly between two spacers. Dynamic and quasi-static finite element calculations are performed to simulate the spent fuel behavior under regulatory defined accident conditions of transport. Beam elements are used for the modeling of the fuel rods representing the compound consisting of claddings and fuel pellets. The dynamic load applied is gathered from an experimental drop test with a spent fuel cask performed at BAM. A hot cell bending test performed at JRC Karlsruhe is the basis for obtaining the material behavior of the fuel rods. The material properties are determined by simulating the test setup of JRC and optimizing the results to fit the experimental load deflection curve. The simulations of the fuel assembly segment are used to get a better understanding about the loads on fuel rods under accident conditions of transport. T2 - 17th International High-Level Radioactive Waste Management Conference (IHLRWM 2019) CY - Knoxville, Tennessee, USA DA - 14.04.2019 KW - Spent Nuclear Fuel KW - Finite Element Simulation KW - Transport packages PY - 2019 SN - 978-1-51088-669-8 SP - 1 EP - 7 AN - OPUS4-52046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad T1 - Numerical simulation of spent fuel segments under transport loads N2 - Packages for the transport of spent nuclear fuel shall meet the International Atomic Energy Agency regulations to ensure safety under different Transport conditions. The physical state of spent fuel and the fuel rod cladding as well as the geometric configuration of fuel assemblies are important inputs for the evaluation of package capabilities under these conditions. Generally, the mechanical behavior of high burn-up spent fuel assemblies under Transport conditions shall be analyzed with regard to the assumptions which are used in the containment and criticality safety analysis. In view of the complexity of the interactions between the fuel rods as well as between the fuel assemblies, basket, and cask containment, the exact mechanical analysis of such phenomena is nearly impossible. The gaps in information concerning the material properties of cladding and pellet behavior, especially for the high burn-up fuel, make the analysis more complicated additionally. As a result, enveloping analytical approaches are usually used by BAM within the safety assessment of packages approved for transport of spent nuclear fuel. To justify the safety margins of such approaches additional analyses are necessary. In this paper, numerical simulations of a segment of a spent fuel assembly are presented. The segment modeled represents the part of a generalized BWR fuel assembly between two spacers. Explicit dynamic finite element calculations are performed to simulate the spent fuel behavior under regulatory defined accident conditions of transport. A beam element formulation is used for the modeling of the fuel rods representing the compound consisting of claddings and fuel pellets. The load applied is gathered from experimental drop tests with spent fuel casks performed at BAM. A hot cell bending test performed at JRC Karlsruhe is the basis for obtaining the material behavior of the fuel rods. The material properties are determined by simulating the test setup of JRC and optimizing the results to fit the experimental load deflection curve. The simulations of the fuel Assembly segment are used to get a better understanding about the loads on fuel rods under accident conditions of transport. T2 - 17th International High-Level Radioactive Waste Management Conference (IHLRWM 2019) CY - Knoxville, Tennessee, USA DA - 14.04.2019 KW - Spent Nuclear Fuel KW - Finite Element Simulation KW - Transport packages PY - 2019 AN - OPUS4-52047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad T1 - Experimental and numerical analyses of spent nuclear fuel behavior under transport conditions N2 - Packages for the transport of spent nuclear fuel shall meet the International Atomic Energy Agency regulations to ensure safety under different transport conditions. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of fuel assemblies are important inputs for the evaluation of the package capabilities under these conditions. The mechanical behavior of spent fuel assemblies shall be analyzed with regard to the assumptions which are used in the containment and criticality safety analysis. The package as a mechanical system is characterized by a complex set of interactions, e. g. between the fuel rods within the assembly as well as between the fuel assemblies, the basket, and the cask containment. This complexity makes it difficult to assume appropriate mechanical loads for the spent fuel inside the package. Another challenge is the assumption of material properties which represent the variation of the fuel rods regarding cladding material, burn-up and the operation history sufficiently. The objective of this paper is to give an overview about the current approaches and research for the evaluation of spent fuel behavior within the package design approval procedure. In this context, analytical, numerical and experimental results are discussed. The presented work is achieved within a collaboration of BAM with national and international partners. T2 - Abteilungskolloquium 3.3 CY - Berlin, BAM Fabeckstraße DA - 02.10.2019 KW - Transportbehälter KW - Radioaktive Stoffe KW - Brennelementverhalten KW - FE-Berechnungen PY - 2019 AN - OPUS4-51173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Wille, Frank T1 - Methodological aspects for finite element modelling of lid systems for type B(U) transport packages N2 - The regulatory compliance of the containment system is of essential importance for the assessment process of Type B(U) transport packages. The requirements of the International Atomic Energy Agency safety standards for transport conditions imply high loading on the containment system. The integrity of the containment system has to be ensured in mechanical and thermal tests. The containment system of German spent nuclear fuel and high level waste transport packages usually includes bolted lids with metal gaskets. The finite element (FE) method is recommended for the analysis of lid systems according to the guideline BAM-GGR 012 for the assessment of bolted lid and trunnion systems. The FE analyses provide more accurate and detailed information about loading and deformation of such kind of structures. The results allow the strength assessment of the lid and bolts as well as the evaluation of relative displacements between the lid and the cask body in the area of the gasket groove. This paper discusses aspects concerning FE simulation of lid systems for type B(U) packages for the transport of spent nuclear fuel and high level waste. The work is based on the experiences of the BAM Federal Institute for Materials Research and Testing as the German competent authority for the mechanical design assessment of such kind of packages. The issues considered include modelling strategies, analysis techniques and interpretation of results. A particular focus of this paper is on the evaluation of the results with regard to FE accuracy, influence of the FE contact formulation and FE modelling techniques to take the metallic gasket into account. KW - Transport cask KW - Closure system KW - Boiled joints KW - Numerical analysis PY - 2012 DO - https://doi.org/10.1179/1746510913Y.0000000021 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 23 IS - 3-4 SP - 211 EP - 216 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-29996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Wille, Frank T1 - Methodological aspects for finite element modeling of lid systems for type B(U) transport packages N2 - The regulatory compliance of the containment system is of essential importance for the assessment process of Type B(U) transport packages. The requirements of the IAEA safety standards for transport conditions implies high loading on the containment system. The integrity of the containment system has to be ensured in mechanical and thermal tests. The containment system of German SNF and HLW transport packages usually includes bolted lids with metal gaskets. The finite element (FE) method is recommended for the analysis of lid systems according to the guideline BAM-GGR 012 for assessment of bolted lid and trunnion systems. FE analyses provide more accurate and detailed information about loading and deformation of such kind of structures. The results allow the strength assessment of the lid and bolts as well as the evaluation of relative displacements between the lid and the cask body in the area of the gasket groove. This paper discusses aspects concerning FE simulation of lid systems for Type B(U) packages for the transport of SNF and HLW. The work is based on the experiences of BAM Federal Institute for Materials Research and Testing as the German competent authority for the mechanical design assessment of such kind of packages. The issues considered include modeling strategies, analysis techniques and the interpretation of results. A particular focus of this paper is on the evaluation of the results with regard to FE accuracy, influence of the FE contact formulation and FE modeling techniques to take the metallic gasket into account. T2 - RAMTRANSPORT 2012 - 9th International Conference on the Radioactive Materials Transport and Storage CY - London, UK DA - 22.05.2012 PY - 2012 IS - Paper 2.2 RAM 27 SP - 1 EP - 8 AN - OPUS4-26353 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -