[1C13-17] Next Generation Reactor Safety

[1C17] Development of failure mitigation technologies for improving resilience of nuclear structures

(14)PRA Analysis Method for Visualizing the Effect of Resilience Improvement Considering Time Effect and Dynamic Change of Events

*Yuto Kuwabara¹, Kazuyuki Demachi¹, Shi Chen¹, Naoto Kasahara¹, Hiroyuki Nishino², Yuichi Onoda², Kennichi Kurisaka² (1. UTokyo, 2. JAEA)

Keywords:Resilience index, Fracture control, Continuous Markov chain Monte Carlo

A visualization method of resilience is indispensable to quantify the effect of improving resilience by introducing fracture control technology to plant systems to prevent the expansion of damage in the event of a non-design basis event. The resilience index developed at the University of Tokyo is a method to visualize the recovery of safety functions by accident management (AM), taking into account the failure probability of components and structures and the time lapse. The time margin brought about by the suppression of fracture expansion is expected to contribute to the recovery of safety performance by enabling the implementation of AM measures that have been excluded in the past, thereby improving resilience. In this study, we have developed a continuous Markov chain Monte Carlo (CMMC) simulation method for plant conditions that introduces the effect of fracture control as a method to visualize this effect.