Document: NUREG-0800
Document ID: 1121c8ce-ab70-416c-9784-421014a1b25b
Document Type: srp
Title: SEISMIC DESIGN PARAMETERS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1419/ML14198A460.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.1
CFR Part: 
CFR Title: 

Content:
deterministic soil profiles developed using the PBSRS to meet the performance goal will establish the design basis for the site-specific SSI analysis; this design basis is developed using the guidance reviewed under SRP Section 2.5.2. For sites with soil layers near the surface that will be completely excavated (defined as excavations to distances sufficiently far from the structures to be considered infinitely far from the facility over the frequency range of interest) and replaced with compacted backfill, the FIRS and PBSRS are determined using the site profiles including the replacement backfill. The competent material is generally considered to be in-situ material having a minimum shear wave velocity of 1,000 fps. Any remaining soft soil or backfill material should be considered in the SSI. According to Appendix S to 10 CFR Part 50, the minimum PGA for the horizontal component of the SSE at the foundation level in the free-field should be 0.1g or higher. The response spectrum associated with this minimum PGA should be a 3.7.1-9 Revision 4 – December 2014 smooth broadband response spectrum (e.g., RG 1.60, or other appropriate shaped spectra, if justified) and is defined as outcrop response spectra at the free-field foundation level. This response spectrum anchored to 0.1g is referred to in this SRP section as the minimum required response spectrum. i. Non-standard Plant Design. For a non-standard plant design (e.g., COL application referencing only an ESP, or a COL application not referencing a DC and ESP), the design response spectra are developed from the site- specific GMRS or from a broadband shaped spectra similar to RG 1.60 which also envelops the site-specific GMRS. Foundation level response spectra (FIRS) consistent with the design response spectra are determined for each seismic Category I structure. These foundation level spectra are compared to the minimum required spectrum to ensure they meet the 0.1g PGA requirement in accordance with Appendix S to