Document: NUREG-0800
Document ID: 2d2b9404-d124-483c-971a-a8f564048299
Document Type: srp
Title: SEISMIC DESIGN PARAMETERS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0706/ML070640306.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.1
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CFR Title: 

Content:
tests, and analyses are performed and the acceptance criteria met, the facility has been constructed and will operate in conformity with the combined license, the provisions of the Atomic Energy Act, and the NRC's regulations.. SRP Acceptance Criteria Specific SRP acceptance criteria acceptable to meet the relevant requirements of the NRC’s regulations identified above are as follows for the review described in this SRP section. The SRP is not a substitute for the NRC’s regulations, and compliance with it is not required. However, an applicant is required to identify differences between the design features, analytical techniques, and procedural measures proposed for its facility and the SRP acceptance criteria and evaluate how the proposed alternatives to the SRP acceptance criteria provide acceptable methods of compliance with the NRC regulations. 1. Design Ground Motion A. Design Response Spectra. The site-specific GMRS reviewed under SRP Section 2.5.2 are determined in the free-field on the ground surface. For sites with soil layers near the surface that will be completely excavated to expose competent material, the GMRS is specified on an outcrop or a hypothetical outcrop that will exist after excavation. Motions at this hypothetical outcrop should be developed as a free surface motion, not as an in-column motion. Although the definition of competent material is not mandated by regulation, a number of reactor designs have specified a shear wave velocity of 1000 fps as the definition of competent material, which is considered acceptable. If non- competent material is present, any excavation and/or backfilling should not alter the development or location of the site-specific GMRS. However, the soft soil or backfill material needs to be considered in the SSI or other analyses. 3.7.1-8 Revision 3 - March 2007 According to Appendix S to 10 CFR Part 50, the minimum peak ground acceleration (PGA) for the horizontal component of the SSE at the foundation level in