Probabilistic risk assessment on maritime spent nuclear fuel transportation-Part I: Transport cask damage probability

This paper proposes a methodology to assess and reduce risks on Spent Nuclear Fuel (SNF) packages from ship collisions with a probabilistic approach. A method to estimate the impact energy upon a collision was elaborated in consideration that whether ships slide or stuck to each other during collision. Structural crash-worthiness of the SNF ship was obtained through a non-linear finite element analysis. Cask damage probability was calculated based on frontal and side cask impact scenarios. This cask damage probability was investigated over various transport parameters which include the number of transport casks carried per shipment, cask stowage configuration, cask loading direction, and ship's cruise velocity. Collision case studies are presented by using reference models of the SNF package, the struck and striking ship. Most and least vulnerable stowage locations on the SNF ship were discovered. The number of casks in a shipment and their stowage method which suppressed cask damage probabilities were identified. The proposed methodology was successful in assisting decision making processes to minimize risks in maritime spent nuclear fuel transportation.