[2E01-07] Advanced Technologies of Design, Management & Evaluation for Nuclear Plants

[2E03] Development of failure mitigation technologies for improving resilience of nuclear structures

(3)Study on Buckling Strength and Post Buckling Behaviors of Reactor Vessel Lower Heads

*Masato Murohara¹, Takuya Sato¹, Naoto Kasahara¹, Akira Yamazaki¹ (1. UTokyo)

Keywords:buckling strength, post buckling behavior, large deformation elastic and plastic analysis, contact boundary, nuclear reactor vessel

As the lessons learned from the Fukushima Daiichi Nuclear Power Plant accident, the importance of controlling the behavior after a failure and mitigating consequences of a failure was recognized. Therefore, the research goal is to improve resilience to safety by mitigating the effects of Beyond Design Basis Events. In this study, in order to clarify post buckling behaviors in nuclear reactor vessels and to propose plans for improving resilience and specific measures, buckling experiments and finite element analysis were subjected on the partial spherical shell in contact with the rigid floor, and the spherical shell with a nozzle. In conclusion, buckling strengths and post buckling behaviors of the partial spherical shell and the spherical shell with a nozzle were revealed.