Session: SE-06-01 The T.H. Liu Memorial Symposium on the Seismic Analysis and Design of Piping Systems-1

Paper Number: 122090

122090 - Fundamental Study on Passive Safety Characteristics of Piping System Against Excessive Earthquake 

As a lesson learned from the Fukushima Daiichi Nuclear Power Plant accident caused by the Great East Japan Earthquake, it has become important not only to prevent failure occurrence, but also to mitigate failure consequence to catastrophic failure after an accident. In this study, the behavior of bent round rods and support columns simulating a piping system subjected to vibration loading was tested and analyzed to demonstrate that the piping system has passive safety characteristics against excessive earthquake.

Vibration tests and vibration analyses show that the natural frequency of the tested system decreases as the collapse of the support columns, and when its natural frequency becomes lower than the input frequency, failure of the tested system hardly progress. From these results, it can be concluded that the tested system become passively safe with respect to vibration loads when its natural frequency decreases below the input frequency. In order to increase the resilience of piping system in nuclear power plants against excessive earthquake, it is effective to have a flexible structure that can easily transition to a passive safety structure immediately when the natural frequency of the piping system falls below the dominant frequency of seismic waves due to failure of the support structure.

 

Presenting Author: Riku Horinouchi the University of Tokyo

Presenting Author Biography: Riku Horinouchi is a first-year master's student in Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo.

Authors:

Riku Horinouchi the University of Tokyo
Yotaro Yamamoto the University of Tokyo
Naoto Kasahara the University of Tokyo