Document: NUREG-0800
Document ID: f86c14d8-f992-49ef-b080-7021bc748b58
Document Type: srp
Title: Design Criteria and Analyses.  In meeting the requirements of 10 CFR Parts 50 and 100,
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1230/ML12302A005.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.5.2
CFR Part: 
CFR Title: 

Content:
analysis and that sufficient conservatism exists in the stability analysis for the horizontal ground motion. Actual test data are needed for both the in situ soils as well as for any materials used in the construction of dams or embankments. As discussed above, the various parameters, such as geometry, soil strength, modeling method (location and number of elements (mesh) if a finite-element analysis is used), and hydrodynamic and pore pressure forces, should be varied to show that there is an adequate margin of safety. Where liquefaction is possible, major dam foundation slopes and embankments should be analyzed by state-of-the-art finite-element or finite difference methods of analysis. Where there are liquefiable soils, changes in pore pressure due to cyclic loading must be considered in the analysis to assess not only the potential for liquefaction but also the effect of pore pressure increase on the stress-strain characteristic of the soil and the post-earthquake stability of the slopes. For the certified design portion of the plant, the site-independent certified seismic design response spectra (CSDRS) are specified as the design basis of the plant and they must be maintained as the design basis. The use of any alternative ground motion would require an exemption or amendment. However, in the case of slope stability and liquefaction analyses, the DCD should specify that the COL applicant will utilize the site-specific GMRS in both the horizontal and vertical directions with appropriate consideration for the elevation of the slope and different subsurface materials. In addition, the GMRS must meet the requirements of Appendix S of, 10 CFR Part 50 with respect to the peak ground acceleration and appropriate shape. Descriptions of the CSDRS and GMRS are provided in SRP Subsections 2.5.2 and 3.7.1. The criteria, design techniques, and analyses are evaluated by the staff to ascertain that: 1 Appropriate state-of-the-art methods have been employed. 2 Conservative