Natural Vibration of Reactor Internals

Earthquakes and Nuclear Power Plant Design.

“…When subjected to earthquake vibrations, many reactor core elements act as beams on end supports. 86 Those in-core portions of any control system that would not necessarily fail to a safe condition under earthquake loadings must be designed with special care, and it is an overriding objective to provide substantial seismic safety margins for the core elements. One conside:r.Rtion in design is that the support conditions, and therefore the stress distributions, may be quite different in testing, shutdown, accident, and operating modes.…”