Document: NUREG-0800
Document ID: 3e1b34e6-0e9d-4d8f-9338-98860adfc499
Document Type: srp
Title: CONCRETE CONTAINMENT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070570009.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.8.1
CFR Part: 
CFR Title: 

Content:
e induced by wind, tornadoes, earthquakes, and pipe rupture, the analysis should consider the nonaxisymmetric effect of these loads. C. Transient and Localized Loads. During normal operation, a linear temperature gradient across the containment wall thickness may develop. After a LOCA, however, the sudden increase in temperature in the steel liner and the adjacent concrete may produce a nonlinear transient temperature gradient across the containment wall thickness. The analysis should consider the effects of such transient loads. In a PWR ice condenser containment, nonaxisymmetric and transient pressure loads resulting from compartmentalization inside the containment will develop after a LOCA. For a BWR pressure-suppression containment, the analysis should consider nonaxisymmetric and transient pressure loads resulting from earthquakes, LOCA, and/or SRV actuation (including fluid-structure interaction). For the effects of such localized and transient loads, the overall behavior of the containment structure should first be determined. A portion of the containment shell, within which the localized or transient load is located, should then be analyzed, using the results obtained from the analysis of the overall vessel behavior as boundary conditions. D. Creep, Shrinkage, and Cracking of Concrete. Creep and shrinkage values for concrete should be established by tests performed on the concrete to be used in the containment structure or from data obtained on completed containments constructed of the same kind of concrete. In establishing these values, the analysis should consider the differences in the environment between the test samples and the actual concrete in the structure. For some containments, cracking of concrete is expected to occur based on the structural integrity test performed in accordance with Article CC-6000 of the ASME Code. Also, based on load combinations that include the design pressure load with earthquake loads, additional concrete cracking would