[2L01-06] New PRA

[2L01] Effect of Failure Modes and Evaluation Methods on Fragility Results in Seismic Fragility Evaluation of Piping Systems

*Yohei Ono¹, Michiya Sakai¹, Ryuya Shimazu¹, Shinichi Matsuura¹ (1. Central Research Institute of Electric Power Industry)

Keywords:Seismic fragility evaluation, Elbow piping, Failure mode, Guillotine break, Fatigue

In most cases, the failure mode of piping in seismic fragility assessment is assumed as guillotine break. But some reports indicate that the failure mode is fatigue. In this study, whether the guillotine break is caused at elbows subjected to in-plane bending was investigated by static tests. Open displacement and close displacement were applied to the elbows respectively. But guillotine break was not observed. The fragility results in which fatigue was assumed as failure mode were improved compared to the results in which guillotine break was assumed as failure mode. In the case of guillotine break, the fragility results evaluated by Detail method were improved compared to the results evaluated by Separation of Variable Method.