Document: NUREG-0800
Document ID: 6d95bc89-e14a-4d87-bf91-1d1760c2aff8
Document Type: srp
Title: FOUNDATIONS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1235/ML12353A388.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.8.5
CFR Part: 
CFR Title: 

Content:
f SSCs important to safety withstand the effects of expected natural phenomena, such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches, without losing the capability to perform their safety functions. The design bases for these SSCs shall reflect appropriate combinations of the effects of normal and accident conditions with the effects of the natural phenomena. To ensure that the design of structures other than containment of a nuclear power plant will withstand natural phenomena, it is necessary to consider the most severe natural phenomena that have been historically reported, allowing sufficient margin for the limited accuracy, quantity, and period of time in which the historical data have been accumulated. These data should be used to specify the design requirements of nuclear power plant components to be evaluated as part of CP, OL, COL, and 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 3.8.5, which also refers to SRP Section 3.8.4, provides detailed acceptance criteria and cites appropriate regulatory guidance for design methodology, materials testing, and construction techniques that are acceptable to the staff. GDC 2 requires that the design of structures other than containment be able to withstand the effects of natural phenomena combined with the effects of normal and accident conditions without losing the capability to perform their safety functions. The primary function of a foundation is to transmit the loads imposed by the superstructure to the foundation material, bedrock, and/or soil supporting the structure. Foundations must be designed to interact with the structures they support. Consequently, it is necessary to specify the most severe natural phenomena (e.g., earthquakes) likely to occur as a function of their frequency of occurrence. The load