Aseismic structure evaluation tests on storage pit

To evaluate the aseismic structural property of a storage pit for vitrified radioactive waste canisters, a full-scale model of the storage pit and canisters filled with dummy vitrified waste were subjected to seismic tests on the shaking table owned by the National Research Center for Disaster Prevention. Three storage pits were tested, all measuring 558.8 mm in diameterx6765 mm in height, of Sch. 40 structural steel plate but with longitudinal internal ribs of different sizes to leave different clearances between the pit and the canister. The dummy canisters, each measuring 430 mm in diameterx1345 mm in height and weighting 480 kg, were piled five high in the pit. The table was shaken in horizontal direction, applying as exciting wave (a) wave pulse, (b) sinusoidal waves in frequency sweep, (c) continuous single-frequency wave and (d) reproduced actual seismic waves. (author)