Document: NUREG-0800
Document ID: e40387bd-a6d6-49ae-a11b-6d22124df03a
Document Type: srp
Title: Each calculated spectrum of the artificial time history is considered to envelop the
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070317.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.0
CFR Part: 
CFR Title: 

Content:
ort. The staff concludes that the seismic design parameters used in the plant structure design are acceptable and meet the requirements of General Design Criterion 2 and Appendix A to 10 CFR Part 100. This conclusion is based on the following. 3.7.1-11 DRAFT Rev. 3 - April 1996 The applicant has met the relevant requirements of GDC 2 and Appendix A to 10 CFR Part 100 by appropriate consideration for the most severe earthquake recorded for the site with an appropriate margin and considerations for two levels of earthquakes - the safe shutdown earthquake (SSE) and operating basis earthquake (OBE). The applicant has met these requirements by the use of the methods and procedures indicated below. The seismic design response spectra (OBE and SSE) applied in the design of seismic Category I structures, systems, and components (SSCs) meets or exceeds the free-field 52 53 response spectra provided in SRP Section 2.5.2. The percentage of critical damping 54 values used in the seismic analysis of Category I structures, systems, and components SSCs are in conformance with Regulatory Guide 1.61, "Damping Values for Seismic 55 Analysis of Nuclear Power Plants." The artificial time history used for seismic design of Category I plant structures, systems, and components SSCs is adjusted in amplitude and 56 frequency content to obtain response spectra that envelop the design response spectra specified for the site and also exhibits sufficient energy in the frequency range of interest. Conformance with the recommendations of Section 2.5.2 and Regulatory Guide 1.61 ensures that the seismic inputs to Category I structures, systems, and components SSCs57 are adequately defined so as to form a conservative basis for the design of such structures, systems, and components SSCs to withstand seismic loadings. 58 For design certification reviews, the findings will also summarize, to the extent that the review is not discussed in other safety evaluation report sections, the staff’s