A Study on the improvement of accuracy of three-dimensional seismic evaluation analysis method for nuclear buildings using a large-scale observation system

Nishida, Akemi  ; Kawata, Manabu; Choi, B.  ; Iigaki, Kazuhiko ; Li, Y. 

We have conducted research and development with the aim of improving the accuracy of three-dimensional seismic evaluation analysis method for nuclear buildings that contributes to probabilistic risk assessment caused by earthquakes (seismic PRA). In 2019, we started our research on improving the accuracy and validating the three-dimensional seismic analysis method used for nuclear buildings using actual seismic observation records in collaboration with the Nuclear Regulation Authority. In this research, we constructed a large-scale observation system that enabled simultaneous observation at multiple positions during natural earthquakes or artificial waves by installing accelerometers not only on/in the soil and on the floors of the building but also on the walls of the building, targeting the High Temperature engineering Test Reactor, which is one of nuclear facilities of JAEA. In this paper, we report the outline of the large-scale observation system and the knowledge obtained from the analysis results of the seismic observation records acquired using this system.