Modeled Structural Transmissibility of a Used Nuclear Fuel Conveyance Applied to Over the Road Test Data and Finite Element Modeling

The Used Fuel Disposition Campaign (UFDC) has been established by the U.S. Department of Energy Office of Nuclear Energy (DOE-NE), to conduct research and development activities related to storage, transportation, and disposal of used nuclear fuel (UNF). The Storage and Transportation staff within the UFDC are responsible for addressing issues regarding the long-term or extended storage (ES) of UNF and its subsequent transportation. Current information is insufficient to determine the ability of UNF, including high-burnup fuel, to withstand shock and vibration loads that could occur when UNF is shipped by rail from nuclear power plant sites to a storage or disposal facility after extended storage. In order to make this determination, the magnitude of the transportation loads transmitted to the UNF must be quantified. Previous preliminary modeling work has shown how the structural transmissibility of the transport system can affect the magnitude of these loads and the importance of modeling all aspects of the transport system (i.e. rail car, transport cradle, cask, canister, and fuel). The work presented herein proposes a methodology for determining the structural transmissibility of a hypothetical transport system, this is then used to scale existing OTR data. The utility of this, is that the resultant scaled data can then be used to compare the as tested configuration to an untested hypothetical configuration. This work will be relevant in creating models of UNF during transport. As such, this paper also presents finite element modeling of the response of a fuel assembly for the existing OTR data and the scaled OTR data. The finite element modeling indicates that the strains in both cases are low, and that no rod to rod interaction is likely to occur.