It becomes important to manage adequately spent nuclear fuels (SNFs) for storage away from reactor and/or final disposal as the plant onsite capacity nearly reaches to saturation state. Although the Korean government has enacted relevant regulations and safety measures including several kinds of test for transport cask, a matter of interest should be extended to protect radioactive contents against accidents in conjunction with their future retrievability as well as transportability if necessary. The objective of this study is to demonstrate integrity of typical SNF rods in a developing dual purpose cask under six postulated 9 m free drop scenarios. At first, a series of finite element (FE) analyses of simplified spent fuel assembly (SFA) with external volume and equivalent mass were performed to find out the most severely damaged ones taking into account heavy computational cost. Subsequently, paired FE analyses were also carried out after detailed modeling of the selected SFA with fuel rods arrangement and practical material properties. Finally, structural integrity of the critical SNF rods was evaluated according to the vertical or oblique drop scenarios. The calculated maximum plastic strains at Zircaloy cladding were compared with specific failure criteria dependent on burn-up levels, of which engineering meaning and incorporated conservatism were discussed.

随着工厂现场容量几乎达到饱和状态，管理充分耗尽的核燃料 (SNF) 以远离反应堆储存和/或最终处置变得很重要。尽管韩国政府已经制定了相关法规和安全措施，包括对运输容器进行多种测试，但在必要时，应将关注的问题扩展到保护放射性内容物免受事故的影响，以及它们未来的可回收性和可运输性。本研究的目的是在六个假设的 9 m 自由跌落场景下证明典型 SNF 棒在开发的双用途桶中的完整性。首先，考虑到大量的计算成本，对具有外部体积和等效质量的简化乏燃料组件 (SFA) 进行了一系列有限元 (FE) 分析，以找出损坏最严重的组件。随后，在对具有燃料棒排列和实际材料特性的选定 SFA 进行详细建模后，还进行了配对有限元分析。最后，根据垂直或倾斜跌落场景评估了关键 SNF 棒的结构完整性。将 Zircaloy 覆层计算的最大塑性应变与取决于燃耗水平的特定失效标准进行比较，讨论了其工程意义和合并的保守性。在对具有燃料棒排列和实际材料特性的选定 SFA 进行详细建模后，还进行了配对有限元分析。最后，根据垂直或倾斜跌落场景评估了关键 SNF 棒的结构完整性。将 Zircaloy 覆层计算的最大塑性应变与取决于燃耗水平的特定失效标准进行比较，讨论了其工程意义和合并的保守性。在对具有燃料棒排列和实际材料特性的选定 SFA 进行详细建模后，还进行了配对有限元分析。最后，根据垂直或倾斜跌落场景评估了关键 SNF 棒的结构完整性。将 Zircaloy 覆层计算的最大塑性应变与取决于燃耗水平的特定失效标准进行比较，讨论了其工程意义和合并的保守性。