Seismic analysis of heavy-liquid-metal-cooled reactor vessels

The linear-elastic seismic analysis for the vessel of a heavy-liquid-metal reactor was undertaken based on the Design Response Spectrum (DRS) approach and for a 0.5 g earthquake. Four support types for the vessel were analyzed and it was found that the roll support exhibits the best overall performance. The variation of the normal-mode frequency and total peak stress intensity with the vessel diameter and thickness was also studied. It was found that the frequency of the first normal mode increases with increasing vessel diameter and thickness, while the total peak stress intensity decreases with increasing vessel thickness and is roughly independent of the vessel diameter. Two new dimensionless groups are introduced that enable correlation of the frequency and stress-intensity data with adequate accuracy. It is proposed that these correlations be used for quick estimate of the seismic response of a vessel of arbitrary size, material and contained (heavy) fluid, subject to an earthquake of arbitrary magnitude.