Document: NUREG-0800
Document ID: 0a8ea59e-ab3a-4182-b590-5dd06be705bb
Document Type: srp
Title: Seismic Wave Transmission Characteristics of the Site.  To meet the
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1230/ML12301A010.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.2.5
CFR Part: 
CFR Title: 

Content:
files are generated for amplification analysis. To develop the randomized subsurface profiles, correlation models appropriate for the site geotechnical information need to be selected. The correlation models used should correspond to the range of correlation from fully correlated to fully uncorrelated, unless otherwise justified. As described in RG 1.208, the mean site amplification curves are then calculated using the different correlation models for each input earthquake scenario to determine the response motion at the free surface. Site amplification analysis is performed and the response motion at the free surface is obtained as the mean response motion at the two levels of the input motion corresponding to mean annual probabilities of exceedance of 10-4 and 10-5. RG 1.208 describes the development of performance-based motion in detail. NUREG/CR-6728, “Technical Basis for Revision of Regulatory Guidance on Design Ground Motions: Hazard- and Risk-Consistent Ground Motion Spectra Guidelines,” describes methods of site response calculation based on one-dimensional subsurface structure approximation, or a flat layer structure. For sites where subsurface structure does not approximate one- 2.5.2-12 Draft Revision 5 – 2013 dimensional or flat layering, two- or three-dimensional analysis might be necessary. During COL reviews, comparison and verification of compliance with appropriate DCD parameters regarding subsurface homogeneity is necessary as well, as it may inform which type of site response analysis is needed. Site amplification studies are performed in a distinct separate step as a part of the determination of the GMRS. In this section, the applicant's site amplification studies are reviewed in conjunction with the geotechnical and structural engineering reviews. Particular emphasis is placed on how the uncertainties inherent in this process are evaluated. To meet the requirements of 10 CFR 100.23, this subsection is acceptable when adequate information