Structural integrity evaluation approach for PWR spent nuclear fuel

PWR fuel assembly (FA) experiences many changes from the time it is manufactured, loaded in the reactor and removed from the reactor for reprocessing or storage etc. Any of these alterations which impact spent nuclear fuel (SNF) integrity should be considered to design a cask/canister. Regarding the cask/canister design, there could be a freedom to design a system that mitigates the forces transmitted to SNF and fuel rods. If the cask/canister design prevents or mitigates forces transmitted to its contents such that structural integrity is not significantly compromised, the detailed SNF properties are necessary to make a decision of the elaborated design parameters. An approach to those work formations is to analyze mechanical characteristics of structural components. Those informations are also used to evaluate hypothetical accident, to select limiting FA for cask/canister to accommodate various kinds of SNFs and to design transportation/storage system for SNFs. Especially, FA structural properties are a sort of essential data. Thus, in this paper, some approaches to evaluate SNF mechanical characteristics are suggested through the existing technical information review, some test data and the analysis methodology, and also closely study the mechanical characteristics of a representative SNF for its general comprehension. (author)