Document: NUREG-0800
Document ID: 45f5d841-54ef-4876-be3e-86eafc6ca90a
Document Type: srp
Title: Each calculated spectrum of the artificial time history is considered to envelop
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1235/ML12352A305.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.0
CFR Part: 
CFR Title: 

Content:
, GDC 2, 10 CFR Part 100, Subpart A and Subpart B, and 10 CFR Part 50, Appendix S. This conclusion is based on the following. The applicant has met the relevant requirements of GDC 2, 10 CFR Part 100, Subpart A and Subpart B, and 10 CFR Part 50, Appendix S by appropriate consideration for the most severe earthquake recorded for the site with an appropriate margin and considerations for two levels of earthquakes - the SSE and OBE. The applicant has met these requirements by the use of the 3.7.1-20 Draft Revision 4 - December 2012 methods and procedures indicated below. The seismic design response spectra (OBE and SSE) applied in the design of seismic Category I SSCs meet or exceed the free-field response spectra provided in SRP Section 2.5.2. For the plant subject to Appendix S of 10 CFR Part 50, the horizontal component of the SSE ground motion in the free-field at the foundation level of the structures is based on an appropriate response spectrum with a peak ground acceleration of at least 0.1g. The percentage of critical damping values used in the seismic analysis of Category I SSCs is in conformance with RG 1.61, "Damping Values for Seismic Design of Nuclear Power Plants." The artificial time history used for seismic design of Category I plant SSCs is adjusted in amplitude and frequency content to obtain response spectra that envelop the design response spectra specified for the site and also exhibits sufficient energy in the frequency range of interest. Conformance with the recommendations of Section 2.5.2 and RG 1.61 ensures that the seismic inputs to the analysis of Category I SSCs are adequately defined so as to form a conservative basis for the design of such SSCs to withstand seismic loadings. The CSDRS used in the certified design of seismic Category I SSCs meet the requirements of 10 CFR 100.23 and Appendix S to 10 CFR Part 50 by either: (1) demonstrating that the CSDRS meet or exceed the site-specific GMRS reviewed and approved in the SRP Section 2.5.2