Document: NUREG-0800
Document ID: 129133a3-2833-4da5-a564-052efbadbeb2
Document Type: srp
Title: but as applied to Category I subsystems.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070319.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.2
CFR Part: 
CFR Title: 

Content:
plate. The latter method of resisting M must be shown to be conservative. o f. The seismically induced hydrodynamic pressures on the tank shell at any level can be determined by the modal and spatial combination methods in SRP Section 3.7.2. The maximum hoop forces in the tank wall must be evaluated with due regard for the contribution of the vertical component of ground shaking. The beneficial effects of soil-structure interaction may be considered in this evaluation, see ASCE Std 4-86, Haroun and Tayel (Reference 14), Veletsos and Tang (Reference 15), and Veletsos and Tang (Refs.erence 4, 11, 12, and 136). 24 The hydrodynamic pressure at any level must be added to the hydrostatic pressure at that level to determine the hoop tension in the tank shell. g. Either the tank top head must be located at elevation higher than the slosh height above the top of the fluid or else must be designed for pressures resulting from fluid sloshing against this head. h. At the point of attachment, the tank shell must be designed to withstand the seismic forces imposed by the attached piping. An appropriate analysis must be performed to verify this design. i. The tank foundation (see also SRP Section 3.8.5) must be designed to accommodate the seismic forces imposed on it. These forces include the hydrodynamic fluid pressures imposed on the base of the tank as well as the tank shell longitudinal compressive and tensile forces resulting from M . o j. In addition to the above, a consideration must be given to prevent buckling of tank walls and roof, failure of connecting piping, and sliding of the tank. Technical Rationale:25 The technical rationale for application of the above acceptance criteria to the seismic subsystem analysis is discussed in the following paragraphs. 1. General Design Criterion 2 requires, in relevant part, that SSCs important to safety be designed to withstand the effects of natural phenomena such as earthquakes, without loss of capability to perform their