[1M12-14] Reactor and Plant Design

[1M13] Numerical examination on passive safety concept for piping system under seismic loads

*Izumi Nakamura¹, Naoto Kasahara² (1. NIED, 2. UTokyo)

Keywords:Excessive seismic load, Piping system, Support structure, Elastic-plastic response behavior, Passive safety structure

For the countermeasure to mitigate the impact of accidents under excessive seismic events beyond the design assumption, a concept of passive-safety structure has been proposed. Taking the piping systems as an example, the passive-safety concept can be realized by causing support failure prior to piping system’s boundary failure. Based on this concept, an analytical case study was conducted on a simplified piping system model with several supports. In the analysis, inelastic characteristics of pipe body and the strength characteristics of pipe supports are considered, and the seismic response and resultant strains are evaluated. In this paper, the feasibility of passive-safety concept on piping systems under seismic events is discussed based on the analysis results.