Document: NUREG-0800
Document ID: f58a3e4a-be8a-4b75-8b11-b41b7a54a500
Document Type: srp
Title: SEISMIC DESIGN PARAMETERS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340564.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.1
CFR Part: 
CFR Title: 

Content:
sis. In practical seismic analysis, which usually employs linear methods of analysis, damping is also used to account for many nonlinear effects such as changes in boundary conditions, joint slippage, concrete cracking, gaps, and other effects that tend to alter response amplitude. In real structures, it is often impossible to separate "true" material damping from system damping, which is the measure of the energy dissipation, from the nonlinear effects. Overall structural damping used in design is normally determined by observing experimentally the total response of the structure. Only the overall damping used for Category I structures, systems, and components is reviewed. When applicable, the basis for any damping values that differ from those given in Regulatory Guide 1.61 (Ref. 3) is reviewed. 3. Supporting Media for Category I Structures The description of the supporting media for each Category I structure is reviewed, including foundation embedment depth, depth of soil over bedrock, 3.7.1-3 Rev. 2 - August 1989 soil layering characteristics, design groundwater elevation, dimensions of the structural foundation, total structural height, and soil properties to permit evaluation of the applicability of finite-element or lumped-spring approaches for soil-structure interaction analysis. 4. Interface of Review Review of geological and seismological information to establish the free- field ground motion is performed as described in SRP Sections 2.5.1 through 2.5.3. The geotechnical parameters and methods employed in the analysis of free-field soil media and soil properties are reviewed as described in SRP Section 2.5.4. The results of the reviews for the operating basis earthquake (OBE) and the safe shutdown earthquake (SSE) site-dependent free-field ground motion, soil properties, etc., are used as an integral part of the seismic analysis review of Category I structures. For those areas of review identified above as being part of other SRP sections, the acceptance