[3J01-05] SeismicPRA

[3J05] Industry's activities to refine direct core damage scenarios in Seismic PRA

*Takahiro Watanabe¹, Shudai Fujimoto², Shuhei Matsunaka³, Bumpei Fujioka⁴, Ryusuke Haraguchi⁵, Takashi KATO⁶, Kensuke Toyoshima⁷ (1. TEPCO HD, 2. KEPCO, 3. TEPSYS, 4. HGNE, 5. MHI, 6. TOSHIBA ESS, 7. NEL)

Keywords:seismic PRA, accident scenario, expert judgment, direct core damage

In the current seismic PRA, it is generally assumed that the initiating events (damage to R/B, CV, RPV, etc.) that are difficult to develop in detail the scenario leading to the core damage are directly lead to the core damage. It gives conservative results. Such a situation needs to be improved from the viewpoint of utilizing risk information such as identifying the vulnerability of the plant. Regarding the issue of this "direct core damage scenario", the industry focused on methodology for "utilization of expert judgement" at home and abroad, and is constructing a process to apply expert judgment to refine the scenario.