Document: NUREG-0800
Document ID: 0f8ca394-8a6b-47e6-8736-3a69b15c9480
Document Type: srp
Title: -
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1319/ML13198A223.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.2
CFR Part: 
CFR Title: 

Content:
Revision 4 – September 2013 Technical Rationale The technical rationale for application of these acceptance criteria to the areas of review addressed by this SRP section is discussed in the following paragraphs: 1. 10 CFR Part 50, GDC 2 requires, in the relevant parts, that SSCs important to safety be designed to withstand the effects of natural phenomena such as earthquakes, without loss of capability to perform their intended safety functions. GDC 2 further requires that the design bases reflect appropriate consideration for the most severe natural phenomena 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 the historical data have been accumulated in the past. These data shall be used to specify the design requirements of NPP components to be evaluated as part of CP, OL, COL, early site permit (ESP) reviews, or for site parameter envelopes in the case of DCs, thereby ensuring that components important to safety will function in a manner that will maintain the plant in a safe condition. SRP Section 3.7.2 describes acceptable methods for the seismic analysis and modeling of seismic Category I structures and major plant systems to assure that they accurately and/or conservatively represent the behavior of SSCs during postulated seismic events. These criteria include acceptable methods/procedures for performing a suitable dynamic analysis, including the effects of SSI. For additional guidance reference is made to RGs 1.92, and 1.122. RG 1.92 provides various procedures acceptable to the staff for combining the three dimensional modal responses for both the response spectrum analysis approach and the time history analysis approach of NPP structures. Additionally, RG 1.122 describes methods acceptable to the NRC staff, as augmented in this SRP section, to be used in developing two horizontal and one vertical in-structure design response spectra at various