Document: NUREG-0800
Document ID: 40e10196-ca2f-4e1c-804d-a8ccd1b7e332
Document Type: srp
Title: Safe Shutdown Earthauake Ground Motion. In this subsection, the
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0529/ML052910327.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.2.6
CFR Part: 
CFR Title: 

Content:
ign. 4. Spectra developed by theoretical-empirical modeling of ground motion may be used to supplement site-specific spectra if the input parameters and the appropriateness of the model are thoroughly documented (e.g., Refs. 13, 28, and 29). Modeling is particularly useful for sites near seismic sources that may experience ground motion that is different in terms of frequency content and wave type from ground motion caused by more distant earthquakes. The SSE response spectra proposed by the applicant are considered acceptable if they meet Regulatory Position 4 and Appendix F of Reference 9. If the independent staff estimates of ground motion are significantly different from those proposed by the applicant, the staff will review the reasons for differences and resolve them as appropriate. The time duration and number of cycles of strong ground motion are required for analysis and design of many plant components. The adequacy of the time history for structural analysis is reviewed under SRP Section 3.7.1. The time history is reviewed in this SRP section to confirm that it is compatible with the seismological and geological conditions in the site vicinity and with the accepted SSE model. At present, models for computing the time history of strong ground motion from a given source-site configuration are limited. Total duration of the motion is acceptable when it is as conservative as values determined using current studies such as References 30 - 33. For evaluation of the liquefaction potential at the site, the time duration and number of cycles of strong ground motion are critical parameters and require additional consideration. If the controlling earthquakes for the site have magnitudes of less than 6, the time history selected for the evaluation of liquefaction potential must have duration and number of strong motion cycles corresponding to at least an event of magnitude 6. III. REVIEW PROCEDURES Upon receiving the applicant's SAR or ESR, an acceptance review is