Seismic Response for a One-Third Scale-Down Vertical Cylindrical Cask Specimen Using Shaking Table Testing

Abstract

This study is aimed to investigate the seismic behavior of the freestanding dry storage cask for spent fuel, several shaking table tests were conducted using a scaled cask model for a real assessment of the characteristics of the seismic response of the cask. First, the harmonic excitation test on the pedestal of the cask was performed to estimate the friction coefficient at the interface between the cask and the pad according to the sliding acceleration response of the pedestal. Then, tests for the seismic response of the cask were conducted for two different setups, the vertical cylindrical concrete cask (VCC) and the concrete cask with an add-on shield which has a square pedestal (VCC+AOS), respectively, using the artificial earthquakes compatible to the design spectrum. In order to verify the often-used analysis method for the seismic response of the cask in engineering practice, the explicit finite element software LS-DYNA was adopted to generate the finite element model of the scale cask with the cask/pad interface modeled by Coulomb’s law of friction and to simulate the shaking table tests. Results indicate that the utilized method gave reasonable cask responses if the variation of the friction coefficient at the cask/pad interface was small during the sliding process.