Seismic-initiated event risk mitigation in lead-cooled reactors : main results of the siler project

This paper gives a general overview of SILER, a Collaborative Project funded within the 7 EC Framework Programme, aimed at studying the risks associated with seismic initiated events in Generation IV Heavy Liquid Metal reactors and developing adequate protection measures. In SILER, the attention is focused on the evaluation of the effects of earthquakes, with particular regard to unexpected (beyond design) events, and to the identification of mitigation strategies like seismic isolation. Specific sections of the paper are addressed to the design, development and testing of the isolators (High Damping Rubber Bearings and Lead Rubber Bearings) and the most critical interface devices like flexible joints for pipelines and joint-cover of the seismic gap. These devices showed excellent behaviour during severe qualification tests in real dynamic conditions and confirmed the reliability of the seismic isolation technique.