[2N06-09] Seismic PRA 2

[2N07] Industry's efforts to refine scenarios directly lead to the core damage in Seismic PRA (Pilot study)

*Takahiro WATANABE¹, Kazumasa SUZUE², Ryusuke HARAGUCHI³, Takashi KATO⁴, Shuhei MATSUNAKA⁵, Bumpei FUJIOKA⁶, Kensuke TOYOSHIMA⁷ (1. TEPCO HD, 2. KEPCO, 3. MHI, 4. TOSHIBA ESS, 5. TEPSYS, 6. HGNE, 7. NEL)

Keywords:seismic PRA, expert assessment, directly lead to core damage, RIDM

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 "scenario directly lead to core damage", the industry focused on methodology for "utilization of expert assessment" at home and abroad, and constructed a process to apply expert assessment to refine the scenario. As the next step, a pilot study is carried out to confirm the applicability to an actual plant.