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:
alysis of nuclear power plants SSCs. In addition, RG 1.61 is referenced for guidance of acceptable damping values to be used in performing dynamic analyses of SSCs. Meeting these requirements provides assurance that seismic Category I SSCs will be adequately designed to withstand the effects of earthquakes, and thus, will be able to perform their intended safety function. 2. 10 CFR Part 50, Appendix S is applicable to applications for a design certification or combined license to 10 CFR Part 52 or a construction permit or operating license pursuant to 10 CFR Part 50 on or after January 10, 1997. For SSE ground motions, 10 CFR Part 50, Appendix S requires that SSCs will remain functional and within applicable stress, strain, and deformation limits. The required safety functions of SSCs must be assured during and after the vibratory ground motion through design, testing, or qualification methods. The evaluation must take into account SSI effects and the expected duration of the vibratory motion. If the OBE is set at one-third or less of the SSE, an explicit analysis or design is not required. If the OBE is set at a value greater than one-third of the SSE, an analysis and design must be performed to demonstrate that the applicable stress, strain, and deformation limits are satisfied. Appendix S also requires that the horizontal component of the SSE ground motion in the free-field at the foundation level of the structures must be an appropriate response spectrum with a peak ground acceleration of at least 0.1g. 3.7.1-18 Draft Revision 4 - December 2012 SRP Section 3.7.1 describes acceptance criteria for developing the required earthquake loadings consisting of the SSE and OBE (if applicable) and other seismic design parameters needed to perform an SSI analysis. This SRP section indicates that an explicit analysis for the OBE, in addition to the SSE, should be performed unless the magnitude of the OBE is set at one-third or less of the SSE. Criteria for the required