Earthquake-Simulator Experiments of a Model of a Seismically-Isolated, Fluoride-Salt Cooled High-Temperature Reactor

Keywords: Molten salt, pebble-bed reactors; graphite reflector; annular tanks; seismic behavior; fluid-structure interaction; base isolation; design recommendations.

Abstract: This report describes earthquake-simulator experiments of a scaled model of a prototype fluoride-salt cooled high-temperature nuclear reactor. The components of the prototype reactor addressed in the experiments include an outer vessel, a concentric core barrel, positively buoyant reflector blocks that act as a moderator, positively-buoyant spherical fuel pebbles, and a molten-salt coolant. A detailed scaling analysis was carried out to support the design of the test specimen. Multi-component seismic inputs were used for testing. Two types of friction pendulum seismic isolation bearings were utilized for the experiments: Single concave Friction Pendulum (SFP) and Triple Friction Pendulum (TFP). The earthquake response of such a reactor model involves multiple non-linear interactions, and the physical test results described in this report provided valuable insights into these behaviors and enabled formulation of analysis and modelling recommendations.