Core Seismic Experiment and Analysis of Hexagonal Bundle Model for Fast Reactor

Abstract

To design fast reactor (FR) core components, seismic response must be evaluated in order to ensure structural integrity. Therefore, advanced analysis method must be developed to calculate seismic response of a fast reactor core. The fast reactor core is generally made of several hundred core elements which are hexagonal flexible beams embedded at the lower support plate in hexagonal arrangement. When a big earthquake occurs, large horizontal displacement, vertical displacement (rising) and impact force of each core element may cause a trouble for control rod insertability and core element intensity. Therefore, a seismic analysis method of a fast reactor core considering three-dimensional nonlinear behavior, such as impact, fluid-structure interaction, was developed. 1/1.5 scale 37 core element mock-ups hexagonal-matrix experiment was performed to validate the core elements vibration analysis code in three dimensions (REVIAN-3D). Vertical behavior (rising displacement) and horizontal behavior (impact force) were good agreement with experiments by the validation of REVIAN-3D.