Document: NUREG-0800
Document ID: 215ec1da-bdbb-48d3-b871-6010c1f4bc55
Document Type: srp
Title: SEISMIC SUBSYSTEM ANALYSIS REVIEW RESPONSIBILITIES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1319/ML13198A239.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.3
CFR Part: 
CFR Title: 

Content:
e criteria provides assurance that seismic Category I subsystems will be adequately designed to withstand the effects of earthquakes, and thus, will be able to perform their intended safety functions. 3.7.3-10 Revision 4 – September 2013 2. 10 CFR Part 50, Appendix S is applicable to applications for a DC or COL to 10 CFR Part 52 or a CP or OL pursuant to 10 CFR Part 50 on or after January 10, 1997. For SSE ground motions, 10 CFR Part 50, Appendix S requires that certain SSCs will remain functional and within applicable stress, strain, and deformation limits. The required safety functions of these SSCs must be assured during and after the vibratory ground motion through design, testing, or qualification methods. The evaluation must take into account SSI effects and the expected duration of the vibratory motion. If the OBE is set at one-third or less of the SSE, an explicit analysis or design is not required. If the OBE is set at a value greater than one-third of the SSE, an analysis and design must be performed to demonstrate that when subjected to the effects of the OBE in combination with normal operating loads, all SSCs of the nuclear power plant necessary for continued operation without undue risk to the health and safety of the public must remain functional and within the applicable stress, strain, and deformation limits. SRP Section 3.7.3 describes acceptable analytical methods that are used to determine the seismic response of subsystems in terms of stresses, strains, and deformations. These responses are combined with the structural responses from other loads in accordance with the criteria in SRP Section 3.8. The criteria in SRP Section 3.7.3 ensure that the effects of SSI and expected duration of the earthquake are appropriately included in the evaluation. In addition, criteria are provided to indicate when the effects of the OBE are required to be considered explicitly in the seismic design of the subsystems. Meeting these acceptance criteria provides