TY - CONF A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Storm, Sven-Uwe A1 - Rudolph, Michael A1 - Schoppa, André A1 - Szczepaniak, Mariusz T1 - Mobile gas cylinders in fire: Consequences in case of failure N2 - Commercial, off-the shelf propane cylinders are subjected to high safety regulations. Furthermore, those cylinders are equipped with safety devices like pressure relief valves (PRV). Despite these regulations and safety measures, a failure of the Container is possible if exposed to an intense fire. The result of this is severe hazard for users, rescue forces and infrastructure. Within the framework of a destructive test series, 15 identical propane cylinders, without pressure relief devices, were exposed to an intensive fire in horizontal Position until failure. Each cylinder was filled with a mass of m =11 kg of liquid propane. Three different fire sources were used (wood, petrol, propane). The experiments revealed the failure of all cylinders in a time period t < 155 s. The failure lead to a fragmentation into several major parts with throwing distances of up to l =262 m. In all trials, the temperature of the cylinder wall (top, side, bottom), of the liquid phase inside and of the surrounding fire (top, side, bottom) was recorded. In addition, the inner cylinder pressure and the induced overpressure of the blast wave after the failure were recorded. Overpressures of up to p=0.27 bar were recorded close to the cylinder (l =5 m). AM tests were documented hy video from several positions (general view, close-up, high-speed 5000 fps). This test series creates the basis for further experimental studies in the field of alternative fuels for vehicles. The aim of this test series is to assess and analyse the consequences of the failure of gas vessels (for LPG, CNG, CGH2) in the aftermath of severe incidents. T2 - 12th International Symposium on Fire Safety Science CY - Lund, Sweden DA - 12.06.2017 KW - Explosion KW - Gas cylinders KW - Consequences PY - 2017 DO - https://doi.org/X0.1016/j.firesaf.2017.05.006 SN - 0379-7112 VL - 91 SP - 989 EP - 996 PB - Elsevier Ltd. AN - OPUS4-43028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Storm, Sven-Uwe A1 - Rudolph, Michael A1 - Schoppa, André A1 - Sczepaniak, Mariusz T1 - Mobile gas cylinders in fire: Consequences in case of failure N2 - Commercial, off-the shelf propane cylinders are subjected to high safety regulations. Furthermore, those cylinders are equipped with safety devices like pressure relief valves (PRV). Despite these regulations and safety measures, a failure of the container is possible if exposed to an intense fire. The result of this is severe hazard for users, rescue forces and infrastructure. Within the framework of a destructive test series, 15 identical propane cylinders, without pressure relief devices, were exposed to an intensive fire in horizontal position until failure. Each cylinder was filled with a mass of m =11 kg of liquid propane. Three different fire sources were used (wood, petrol, propane). The experiments revealed the failure of all cylinders in a time period t < 155 s. The failure lead to a fragmentation into several major parts with throwing distances of up to l =262 m. In all trials, the temperature of the cylinder wall (top, side, bottom), of the liquid phase inside and of the surrounding fire (top, side, bottom) was recorded. In addition, the inner cylinder pressure and the induced overpressure of the blast wave after the failure were recorded. Overpressures of up to p=0.27 bar were recorded close to the cylinder (l =5 m). All tests were documented by video from several positions (general view, close-up, high-speed 5000 fps). This test series creates the basis for further experimental studies in the field of alternative fuels for vehicles. The aim of this test series is to assess and analyse the consequences of the failure of gas vessels (for LPG, CNG, CGH2) in the aftermath of severe incidents. KW - Explosion KW - Gas cylinders KW - Consequences PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S037971121730098X DO - https://doi.org/10.1016/j.firesaf.2017.05.006 SN - 0379-7112 SN - 1873-7226 VL - 91 SP - 989 EP - 996 PB - Elsevier AN - OPUS4-40550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krentel, Daniel A1 - Rudolph, Michael A1 - Tschirschwitz, Rico A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Schalau, Bernd A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz A1 - Mair, Georg W. T1 - Infrared radiation measurement at failure of mobile gas vessels N2 - 15 identical off-the-shelf propane cylinders (m = 11 kg liquid propane) were underfired. The infrared Radiation of the Explosion, that occurred in the aftermath of the vessel failure, was recorded using four bolometers. These measurements are compared with an estimation of the Maximum intensity gained by an Analysis of the Video data, an Extended Version of the Stefan-Boltzmann law and a BLEVE model. T2 - 26th International Colloquium on the Dynamics of Explosions and Reactive Systems CY - Boston, USA DA - 30.07.2017 KW - Failure of gas vessels KW - Propane cylinder KW - Gas explosion KW - Consequences KW - Infrared radiation PY - 2017 SP - 1 EP - 6 PB - FM Global CY - Seattle, USA AN - OPUS4-41993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Wille, Frank A1 - Droste, Bernhard T1 - Introduction of BAM safety assessment experience feedback list N2 - BAM as competent authority regarding assessment of mechanical and thermal design, activity release and quality assurance aspects of SNF and HLW transport packages developed a thesaurus of experience feedback topics from recent approval procedures. The list is structured according to the European PDSR guide. It involves issues, which from BAM point of view, needed clarification during last package design assessment procedures. The list contains issues from operation (e.g. deactivation of handling lugs not intended for package handling), maintenance (e.g. leak tightness of impact limiting devices) to technical assessment (e.g. formation of hydrogen by radiolysis and its impact on pressure and ignitability, consideration of ageing mechanisms, thermo-mechanical assessment, impact of gaps between content and flask, spent fuel behaviour) as well as to general and specific safety analysis report requirements (e.g. report structure and required data). T2 - PATRAM 2016 CY - Kobe, Japan DA - 18.09.2016 KW - Experience feedback list KW - Radioactive material KW - Transport PY - 2016 UR - http://www.patram2016.org/ SP - Paper 4002, 1 AN - OPUS4-37850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin T1 - Experience feedback from BAM safety assessment of transport packages N2 - In order to facilitate approval procedures and reduce effort BAM has filed a list of recently encountered issues during different approval procedures. This presentation shows different examples from the list, which are structured according to the PDSR guide. T2 - RAM Tage CY - Berlin, Germany DA - 16.03.2016 KW - Experience feedback list KW - Radioactive material PY - 2016 AN - OPUS4-37848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin T1 - Introduction of BAM safety assessment experience feedback list N2 - BAM as competent authority regarding assessment of mechanical and thermal design, activity release and quality assurance aspects of SNF and HLW transport packages developed a thesaurus of experience feedback topics from recent approval procedures. The list is structured according to the European PDSR guide. It involves issues, which from BAM point of view, needed clarification during last package design assessment procedures. The list contains issues from operation (e.g. deactivation of handling lugs not intended for package handling), maintenance (e.g. leak tightness of impact limiting devices) to technical assessment (e.g. formation of hydrogen by radiolysis and its impact on pressure and ignitability, consideration of ageing mechanisms, thermo-mechanical assessment, impact of gaps between content and flask, spent fuel behaviour) as well as to general and specific safety analysis report requirements (e.g. report structure and required data). T2 - PATRAM 2016 CY - Kobe, Japan DA - 18.09.2016 KW - Experience feedback list KW - Radioactive material KW - Transport PY - 2016 AN - OPUS4-37852 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Wille, Frank A1 - Droste, Bernhard T1 - Experience feedback from BAM safety assessment of transport packages N2 - BAM as competent authority regarding assessment of mechanical and thermal design, activity release and quality assurance measures of Type-B(U) transport packages developed a thesaurus of experience feedback topics from recent assessment procedures. The list is structured according to the European PDSR guide. It involves issues, which from BAM's point of view, needed clarification during the last package design assessment procedures. The list contains issues from Operation (e.g. deactivation of handling lugs not intended for package handling), maintenance (e.g. leak tightness of impact limiting devices) to technical assessment (e.g. formation of hydrogen by radiolysis and its impact on pressure and ignitability, consideration of ageing mechanisms, thermo-mechanical assessment, impact of gaps between content and flask) as well as to general and specific safety analysis report requirements (e.g. report structure and required data). T2 - RAMTRANS 2015 - 10th International conference on radioactive materials transport and storage CY - Oxford, UK DA - 19.05.2015 KW - Transport KW - RAM KW - Radioactive material KW - Cask KW - Flask KW - Nuclear fuel PY - 2015 SP - 1 EP - 7 AN - OPUS4-33420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisenacher, Germar A1 - Wille, Frank A1 - Droste, Bernhard A1 - Neumann, Martin T1 - Modeling of wood filled impact limiters for transport packages - 14111 N2 - Packages for the transport of SNF and HLW are usually equipped with impact limiters to reduce the loads that result from the regulatory 9 m drop test. A common impact limiter design in Germany is a welded steel sheet structure filled with wood. The material wood is the main energy absorber, while the steel sheet provides the integrity of the impact limiter. The IAEA allows mechanical safety cases of transport packages to be carried out computationally, as long as the models used are reliable. In this context, a Finite Element (FE) modeling approach for wood and its application to impact limiters in the calculation of a 9 m drop test is presented. A user material model for wood was developed for the dynamic FE-Code LS-DYNA. Its features are based on a series of crush tests with spruce wood specimens. The model considers wood as a material with transversely isotropic properties, i.e. in the directions parallel and perpendicular to the fiber. The plastic material behavior depends on the state of stress. This has shown to be important to account for the lateral constraint of wood in impact limiters resulting from steel sheet encapsulation. Lateral constraint or respectively, a multiaxial stress state, increases the compression strength level of wood, limits the softening effect and increases the hardening effect. Lateral constraint also increases volumetric and reduces deviatoric deformation. The wood material model considers various hardening and softening characteristics via input flow curves. It considers effects of temperature and strain rate on strength as well. The development of a multi-surface yield criterion and a plastic potential that enables the user input of plastic Poisson's ratios were the challenges during the development of material model. A dynamic FE calculation of a horizontal drop test with an 18,000 kg test package was performed. The wood material model was used to model the wooden impact limiter inlays. The impact limiter deformation and the package deceleration were compared to the experimental drop test results to rate the performance of the wood material model. T2 - WM2014 Conference CY - Phoenix, Arizona, USA DA - 02.03.2014 KW - Transport package KW - Radioactive material KW - Spruce wood KW - Impact limiter KW - Material model KW - Finite element PY - 2014 SN - 978-0-9836186-3-8 SP - 1 EP - 10 AN - OPUS4-30653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Wille, Frank A1 - Linnemann, Konrad A1 - Schubert, Sven A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Droste, Bernhard T1 - Reflection on BAM mechanical design assessment of TN®24E spent fuel transport package N2 - TN®24 E, a new package design, was developed and applied for by Areva TN for German transport approval certificate. The certificate was issued by BfS, Federal Office for Radiation Protection, on 24th of July 2013. The package is designed as a dual purpose cask for transport and storage of up to 21 PWR spent fuel assemblies from German NPPs. BAM is the German competent authority responsible for the design assessment of RAM packages regarding mechanical and thermal safety cases, activity release analysis and all issues of quality assurance during manufacturing and operation of packages. Certain assessment experiences as well as new developments resulting from the BAM TN®24E approval procedure are presented. The mechanical safety case of the TN®24E is based mainly on finite element calculations, which were verified by the TN®81 1/3 scale drop test program performed at BAM. Thermal analyses rely upon calculations, while the activity release criterion is based upon leakage rate results of TN®81 drop tests. The BAM-GGR 012 guideline for the analysis of bolted lid and trunnion systems has been fully implemented. Due to requirements by BAM, AREVA TN developed a new assessment strategy for fracture mechanical evaluation of welding seams. The material qualification and documentation is also an important aspect of BAM assessment; the qualification of borated aluminum basket material, the determination of strength values for thermal aged hardened aluminum alloys for the basket or consideration of high burn-up fuel assemblies are remarkable issues in this context. In addition, the consideration of the material compatibility, especially taking into account a transport after 40 years of dry interim storage in German facilities, has gained significant importance in the licensing process of the TN®24E. Next to obvious mechanical issues such as the assessment of shell ovalization under 9 m drop test scenario and its impact on basket load, thermo-mechanical interactions had to be addressed in the safety case. Due to BAM requirements, AREVA TN performed a full thermo-mechanical analysis of the cask behavior under fire test conditions. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Transport KW - RAM KW - Radioactive material cask KW - Nuclear fuel PY - 2013 SP - 1 EP - 12 PB - Omnipress AN - OPUS4-30270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisenacher, Germar A1 - Scheidemann, Robert A1 - Neumann, Martin A1 - Wille, Frank A1 - Droste, Bernhard T1 - Crushing characteristics of spruce wood used in impact limiters of type B packages N2 - The material spruce wood is frequently used in impact limiters of Type B transport packages. In order to develop and parametrize an appropriate finite element material model, the crushing characteristics of spruce wood have been determined. A large number of crush tests was performed at BAM test facilities to generate a comprehensive data base. The parameter range in the crush test series results amongst others from the IAEA Regulations for the Safe Transport of Radioactive Material: e. g., the minimum temperature considered was -40 °C and the maximum strain rate applied was derived from the 9 m drop test. Cubical spruce wood specimens were tested using a servo hydraulic impact testing machine for initial strain rates of up to 30 1/s. A machine for guided drop tests was used for initial strain rates of up to 133 1/s. Drop masses of up to 1,200 kg were therefore used from drop heights of up to 9 m. The results presented in the paper include force-displacement characteristics and deformation behavior of spruce wood. Thereby the effects of strain rate, temperature, fiber-load orientation and lateral constraint are considered. Higher strain rates led to increasing crush forces, especially for loading perpendicular to the fiber. Higher temperature resulted in decreasing crush forces. The crush force level was significantly lower for load perpendicular to the fiber and the crushing characteristics differed compared to load parallel to the fiber. Without lateral constraint, the specimens expanded laterally, i. e. the plastic Poisson's ratio (if wood is considered a continuum) was not zero. Crush forces were comparably low and for load parallel to the fiber there was a significant softening effect. Lateral constraint of the specimens increased the crush force level and limited the softening effect. The results of the crush tests are used to derive modeling requirements and some assumptions for the development of a finite element material model for spruce wood. Possible future research work is pointed out. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Spruce wood KW - Crush test KW - Impact limiter PY - 2013 SP - 1 EP - 10 PB - Omnipress AN - OPUS4-30219 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 DO - 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 - Eisenacher, Germar A1 - Kuschke, Christian A1 - Schubert, Sven A1 - Neumann, Martin A1 - Sterthaus, Jens A1 - Nitz, Thilo A1 - Wille, Frank T1 - Moisture content of wood - influence on mechanical behavior of wood filled impact limiter and importance for quality surveillance during manufacturing N2 - The moisture content of wood is known to have a significant influence on the wood’s mechanical properties. Using wood as an energy absorber in impact limiter of packages for the transport of radioactive material, it is of particu-lar importance to ensure the moisture content and thus relevant mechanical properties to be in specified limits. The paper surveys the influence of wood moisture content on the mechanical properties of wood. Different measuring methods are discussed with respect to in-situ applicability, accuracy and effort. The results of an experimental ana-lysis of the accuracy of hand-held moisture meters using the electrical resistance method are discussed. Conclu-sions are drawn regarding the measurement of moisture content of wood upon delivery as well as of complete im-pact limiter assemblies. Requirements for quality surveillance during manufacturing of wood filled impact limiter are derived and it is exemplified how to meet them. Construction, manufacturing and inspection of impact limiter encapsulation with regard to leak-tightness are addressed. T2 - RAMTRANSPORT 2012 - 9th International Conference on the Radioactive Materials Transport and Storage CY - London, UK DA - 2012-05-22 KW - Mechanical behavior of wood KW - Moisture content KW - Impact limiter PY - 2012 IS - 4.4 RAM 30 SP - 1 EP - 11 AN - OPUS4-26241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eisenacher, Germar A1 - Kuschke, Christian A1 - Schubert, Sven A1 - Neumann, Martin A1 - Sterthaus, Jens A1 - Nitz, Thilo A1 - Wille, Frank T1 - Moisture content of wood: influence on mechanical behaviour of wood filled impact limiters and importance for quality surveillance during manufacturing N2 - The moisture content of wood is known to have a significant influence on the wood's mechanical properties. Using wood as an energy absorber in impact limiters of packages for the transport of radioactive material, it is of particular importance to ensure the moisture content and thus relevant mechanical properties to be in specified limits. The paper surveys the influence of wood moisture content on the mechanical properties of wood. Different measuring methods are discussed with respect to in situ applicability, accuracy and effort. The results of an experimental analysis of the accuracy of hand held moisture metres using the electrical resistance method are discussed. Conclusions are drawn regarding the measurement of moisture content of wood upon delivery as well as of complete impact limiter assemblies. Requirements for quality surveillance during manufacturing of wood filled impact limiters are derived and it is exemplified how to meet them. Construction, manufacturing and inspection of impact limiter encapsulation with regard to leak tightness are addressed. KW - Electrical resistance method KW - Impact limiter KW - Moisture content KW - Moisture metre KW - Wood PY - 2012 DO - https://doi.org/10.1179/1746510913Y.0000000023 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 23 IS - 3-4 SP - 179 EP - 185 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-29243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dreßler, Martin A1 - Nofz, Marianne A1 - Dörfel, Ilona A1 - Saliwan Neumann, Romeo T1 - Diffusion of Cr, Fe, and Ti ions from Ni-base alloy inconel-718 into a transition alumina coating N2 - Heat treating metals at high temperatures trigger diffusion processes which may lead to the formation of oxide layers. In this work the diffusion of Cr, Fe and Ti into an alumina coating applied to Inconel-718 is being investigated. Mass gain measurements, UV–vis spectroscopy and transmission electron microscopy were applied in order to study the evolution of the diffusion process. It was found that mainly Cr as well as minor amounts of Fe and Ti are being incorporated into the alumina coating upon prolonged heat treatment at 700 °C. It could be shown that alumina coatings being void of Cr have the same oxidation related mass gain as uncoated samples. However, incorporation of Cr into the alumina coating decreased their mass gain below that of uncoated substrates forming a Cr oxide scale only. KW - Diffusion KW - UV–vis spectroscopy KW - Transmission electron microscopy KW - Alumina coatings KW - Sol-gel deposition PY - 2012 DO - https://doi.org/10.1016/j.tsf.2012.02.006 SN - 0040-6090 VL - 520 IS - 13 SP - 4344 EP - 4349 PB - Elsevier CY - Amsterdam AN - OPUS4-25830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 - Neumann, Martin A1 - Ballheimer, Viktor A1 - Sterthaus, Jens A1 - Schubert, Sven A1 - Eisenacher, Germar A1 - Wille, Frank T1 - Material characterization and modeling within safety analysis of packages for transport of radioactive material N2 - In mechanical design safety assessment ofpackages for the transport of radioactive material the International Atomic Energy Agency (IAEA) regulations [1,2] require the use of one of four methods of demonstration of compliance with regulations: tests with prototypes, reference to previous satisfactory demonstrations, tests with scaled models as well as calculation or reasoned argument. In all cases characterization of material behavior is necessary. The need for material characterization can be split into three groups: characterization for material modeling in the design and verification process, determination of assessment criteria and inspections during manufacturing. The paper deals primarily with material characterization for the material modeling in the design phase and authorities approval process. Main package components are discussed: cask body and lids, screws, trunnions, impact limiter and basket(structure holding the content in specified position). Depending on the material used for these components this paper Shows exemplary a possible set of material investigations in order to allow modeling in design and assessment during the approval process. T2 - ASME 2012 Pressure vessels & piping division conference CY - Toronto, Ontario, Canada DA - 15.07.2012 PY - 2012 SP - PVP2012-78297, 1-6 PB - American Society of Mechanical Engineers CY - New York AN - OPUS4-26271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisenacher, Germar A1 - Scheidemann, Robert A1 - Neumann, Martin A1 - Wille, Frank A1 - Droste, Bernhard T1 - Approach for a finite element material model for wood for application in mechanical safety cases of transport packages N2 - BAM Federal Institute for Materials Research and Testing is the competent authority for mechanical safety assessment of transport packages for radioactive material in Germany. The further development of state-of-the-art technology concerning assessment methods is essential for a qualified work of involved designers and authority experts. The paper gives an example of current development done to improve understanding and modeling capabilities of wood filled impact limiter. In order to reduce the loads applied to the package containment, which result from regulatory drop tests, most packages are protected by energy dissipating impact limiter. Wood, encapsulated by steel sheets, is one of the materials typically used for energy dissipation in these impact limiter. Very often, mechanical safety cases regarding the 9 m drop test are performed computationally, where it is essential to use reliable and verified computational methods and models. In this context, the paper presents an approach for a finite element material model for wood. Thereby, the mechanical behavior of wood under compression loading is the focus of the development work. Additionally, material orientation as well as strain rate, temperature and lateral constraint may vary. A large number of experiments, particularly compression tests, was designed and performed to establish an adequate experimental database for modeling verification. The experimental results enabled the derivation of necessary requirements: The material model has to take into account strain rate and temperature dependencies as well as the anisotropic characteristics of the material, a proper yield criterion, flow rule and hardening law. Such a material model is currently not available in established commercial dynamic finite element codes. Thus it is necessary to create a user-defined material model considering the mentioned requirements. A first step was done by determining a yield surface as well as detecting flow and hardening mechanisms from experimental force-deflection curves. In a next step the LS-DYNA material model MAT_75 was altered according to conclusions of former BAM development work, regarding the modeling of post-peak softening as a function of lateral constraint. Future research will contain the further development, implementation and verification of a material model for wood. T2 - 52nd INMM Annual meeting CY - Palm Desert, CA, USA DA - 17.07.2011 KW - Impact limiter KW - Material model wood KW - Transport package PY - 2011 SP - 1 EP - 8 AN - OPUS4-24236 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Komann, Steffen A1 - Neumann, Martin A1 - Ballheimer, Viktor A1 - Wille, Frank A1 - Weber, Mike A1 - Qiao, Linan A1 - Droste, Bernhard T1 - Mechanical assessment within type B packages approval: application of static and dynamic calculation approaches N2 - This paper demonstrates exemplarily how numerical and experimental approaches can be combined reasonably in mechanical assessment of package integrity according to the IAEA regulations. The paper also concentrates on the question about how static mechanical approaches can be applied, and what their problems are in relation to dynamic calculation approaches. Under defined impact tests, which represent accident transport conditions, the package has to withstand impact loading, e.g. resulting from a 9 m free drop onto an unyielding target in sequence with a 1 m puncture drop test. Owing to the local character of the interaction between the puncture bar and the cask body, it is possible to develop a dynamic numerical model for the 1 m puncture drop which allows an appropriate simulation of the interaction area. Results from existing experimental drop tests with prototype or small scale cask models can be used for verification and validation of applied analysis codes and models. The link between analysis and experimental drop testing is described exemplarily by considering a regulatory 1 m puncture bar drop test onto the cask body of a recently approved German high level waste transport package. For the 9 m drop test of the package, it is difficult to develop a dynamic numerical model of the package due to the complexity of the interaction between cask body, impact limiters and unyielding target. Dynamic calculations require an extensive verification with experimental results. The simulation of a 9 m drop of a package with impact limiters is thereby often more complex than the simulation of a 1 m puncture drop onto the cask body. A different approximation method can be applied for the consideration of dynamic effects on the impact loading of the package. In a first step, maximum impact force and rigid body deceleration of the cask body during the impact process can be calculated with simplified numerical tools. This rigid body deceleration can subsequently be applied on a verified static numerical model. Dynamic effects, which cannot be covered by the static numerical analysis, have therefore to be considered by using an additional dynamic factor. The paper describes this approach exemplarily for a 9 m horizontal drop of a typical spent fuel cask design. KW - Package assessment KW - Package KW - Packaging KW - Structural analysis PY - 2011 DO - https://doi.org/10.1179/1746510911Y.0000000012 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 22 IS - 4 SP - 179 EP - 183 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-26448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Martin A1 - Herter, Jürgen A1 - Droste, Bernhard A1 - Hartwig, S. T1 - Compressive behaviour of axially loaded spruce wood under large deformations at different strain rates N2 - Impact limiting components of packages for the transport of radioactivematerials are often designed as wood filled steel constructions. Wood absorbs major part of the impact energy in order to minimise the impact load acting upon the containment. Dynamic impact experiments with wood filled impact limiters showed different crushing mechanisms for axially loaded wood depending on their lateral constraint. Tests on spruce wood samples (Picea abies) were performed in order to clarify the influence of strain rate from static to 30 s-1 on a) compression strength, b) stress at a global strain level of 50%, and c) energy absorption capacity at 50% deformation, including statistical evaluation of the results. Results were as follows: strain rate increase led to significantly higher compression strength, stress and strain energy at a strain level of 50%. Lateral strain restriction had no effect on compression strength; it had a significant effect on stress and strain energy at strain level of 50%. Therefore, the definition of a general yield curve for wood under large deformations is not possible, the yield curve has to be chosen taking into account lateral constraints. KW - Compression KW - Wood KW - Spruce KW - Picea abies KW - Impact PY - 2011 DO - https://doi.org/10.1007/s00107-010-0442-x SN - 0018-3768 VL - 69 IS - 3 SP - 345 EP - 357 PB - Springer CY - Berlin ; Heidelberg AN - OPUS4-22980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dreßler, Martin A1 - Dombrowski, Felix A1 - Simon, Ulla A1 - Börnstein, Julian A1 - Hodoroaba, Vasile-Dan A1 - Feigl, Michael A1 - Grunow, Sabrina A1 - Gildenhaar, Renate A1 - Neumann, Martin T1 - Influence of gelatine coatings on compressive strength of porous hydroxyapatite ceramics N2 - Porous ceramics prepared by the foam replication technique have a high porosity and low mechanical stability. It has been reported that coating such porous ceramics with gelatin allows for an improved compressive strength. Little details regarding the influence of important gelatin parameters such as concentration, temperature and drying conditions as well as bloom number which is a measure of the gel rigidity, on this toughening effect are available. This paper investigates the influence of these parameters on compressive strength of gelatin coated porous hydroxyapatite ceramics. It was found that concentration in the gelatin sols has a marked impact whereas sol temperature, bloom number and differing conditions during subsequent drying have only little influence on the compressive strength of the coated ceramics. KW - Films KW - Composites KW - Strength KW - Apatite KW - Biomedical application PY - 2011 DO - https://doi.org/10.1016/j.jeurceramsoc.2010.11.004 SN - 0955-2219 SN - 1873-619X VL - 31 IS - 4 SP - 523 EP - 529 PB - Elsevier Ltd. CY - Oxford AN - OPUS4-23216 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -