Document: NUREG-0800
Document ID: b5a87a6e-5e73-493f-b8d9-5de2b5feba56
Document Type: srp
Title: SEISMIC DESIGN PARAMETERS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070317.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.1
CFR Part: 
CFR Title: 

Content:
e 22 earthquakes that have been historically reported for the site and surrounding area with sufficient margin for the limited accuracy, quantity, and period of time in which historical data have been accumulated. 2B. For Appendix A to 10 CFR Part 100 - Two earthquake levels, the safe shutdown 23 24 earthquake (SSE) and the operating basis earthquake (OBE) , shall be considered in the 25 26 design of the safety-related structures, components, and systems.27 3.7.1-5 DRAFT Rev. 3 - April 1996 Specific criteria necessary to meet the relevant requirements of GDC 2 and Appendix A to 10 CFR Part 100are described below. The acceptance criteria for the areas of review described in subsection I above are as follows.:28 1. Design Ground Motion a. Design Response Spectra The proposed OBE and SSE design response spectra for use in analyses and design of structures, systems, and components SSCs should, generally, meet or 29 exceed amplitudes of the site-specific spectra at all frequencies. The use of generic spectra, such as Regulatory Guide 1.60 (Ref. 5) spectra, as design 30 spectra is also acceptable provided that their use is consistent with the information reviewed in SRP Section 2.5.2. To be acceptable, the design response spectra should be specified for three mutually orthogonal directions - two horizontal and one vertical. Current practice is to assume that the maximum ground accelerations in the two horizontal directions are equal. b. Design Time History The SSE and OBE design time histories to be used in the free field of the soil media shall be consistent with those developed or specified in Section 2.5.2. For both horizontal and vertical input motions, either a single time history or multiple time histories can be used. For linear structural analyses, using site-independent response spectra (e.g., Regulatory Guide 1.60), the total duration of the artificial accelerogram should be long enough such that adequate representation of the Fourier components at low frequency