PERFORMANCE-GOAL BASED (RISK INFORMED) APPROACH FOR ESTABLISHING THE SSE SITE SPECIFIC RESPONSE SPECTRUM FOR FUTURE NUCLEAR POWER PLANTS

摘要

The Safe Shutdown Earthquake (SSE) Site-Specific Response Spectrum (SSRS) for future nuclear power plants can be established following the Performance-Goal Based (Risk Informed) Approach defined in the ASCE (2005) Standard 43-05. The standard is a professional consensus committee developed standard. This standard is formally constructed to produce designs aimed at achieving a target acceptable seismic risk goal, defined as the annual probability of seismic induced unacceptable performance. The first step in this process is to develop a risk-consistent or Uniform Risk Response Spectrum (URRS) which will be used as the SSRS. When these URRSs are used as the SSRSs, plants at different sites (all designed to the same design criteria, such as NUREG 0800, for their particular SSRSs) should have consistent seismic risks. In contrast, this risk-consistency goal is not achieved when a Uniform Hazard Response Spectrum (UHRS) is used; the UHRS fails to reflect the fact that the seismic hazard curves at different sites have substantially different slopes, and consideration of these slopes is critical to obtaining risk-consistent seismic designs. As described below, the URRS does depend on both the UHRS and these slopes.