Abstract
In nuclear power stations, the storage of a lot of spent fuels is becoming a serious problem because of the shortage of the residual space of the spent fuel pool. It is planned to construct an another plant where the spent fuels are temporarily stored. In that plant, the spent fuels will be installed in a container called canister. The canister, in turn, will be stored in an outer cylindrical container called cask, which will be a free-standing structure. Thus, the cask-canister system is seen as a two-degree-of-freedom coupled system. Therefore, it is very important to evaluate the sliding motion of the cask-canister system subjected to seismic excitations. In an analytical model, the canister and the cask are treated as rigid bodies that are connected by a spring and a dashpot, and liquid is encapsulated in an annular region between the cask and the canister. The equations of motion are derived for the sliding motion when the floor is subjected to a horizontal base excitation. The sliding displacement of the cask and the relative displacement of the canister against the cask are evaluated by numerical simulations. The effects of the liquid in the annular region is effective in reducing the sliding motion of the cask.
