Validation of nonlinear FEA models of a thin-walled elbow under extreme loading conditions for sodium-cooled fast reactors

Watakabe, Tomoyoshi; Jin, C.*; Usui, Yoshiya*; Sakai, Shinkichi*; Wakai, Takashi ; Oshika, Junji*; Tsukimori, Kazuyuki

For the purpose of confirming failure modes and safety margin, some studies on the ultimate strength of thin-walled piping components for Sodium-cooled Fast Reactors (SFRs) under extreme loading conditions such as large earthquakes have been reported these several years. Nonlinear finite element analysis has been applied in these studies to simulate buckling and yielding with large deformation, whose accuracy is dependent on the element type, the mesh size, the elasto-plastic model and so on. It is important to check the validation of a finite element model for nonlinear analysis especially under extreme loading conditions. This paper presents static and dynamic analyses of a thin-walled elbow with large deformation under large seismic loading, and discusses the validation of the FEA models comparing with experimental results.