This paper presents the isolation performance of a three-dimensional base isolated Sodium-cooled Fast Reactor building. The three-dimensional isolation system consists of rubber bearing with the horizontal oil damper for the horizontal isolation system and disc spring units with vertical oil dampers for the vertical one, where the vertical one is set under the horizontal one to be arranged in series.
These elements excepting the horizontal oil damper have been developed for the three-dimensional isolation system through the static or the dynamic loading tests using a full scale or a half scale model. Regarding the horizontal oil damper which is necessary for the three-dimensional isolation system as well as the horizontal isolation system, the details would be described in Part 6.
The authors also have been tackled to create the analytical modeling for each element such as the disc spring units, vertical oil damper and rubber bearing. The previous studies from part 1 to part 4 clarified that the newly analytical model, each of which is defined by the differential equations, could accurately express relationships between the force and displacement of each element.
To demonstrate the reduction effect (performance) of the seismic responses for the three-dimensional isolation system, the seismic response analyses using newly analytical modeling were performed for the Sodium-cooled Fast Reactor building that is modeled into the multi-degree-of-freedom-system. The isolation performance of the three-dimensional isolation system is verified through the floor response spectra evaluated at the position where the primary components are placed, in comparison with those by the conventional 2D horizontally isolation system using the rubber bearing without the vertical elements.