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 - Neumann, Martin T1 - Reflection on BAM design assessment of TN24E spent fuel transport package T2 - PATRAM 2013 CY - San Francisco, CA, USA DA - 2013-08-18 PY - 2013 AN - OPUS4-29764 LA - deu 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 -