HTGR Knowledge Base

Conference Article: Experimental and theoretical evaluation of core alignment structures against a seismic load

Ide, A.; Miki, T. (Fuji Electric Co. Ltd., Tokyo (Japan)); Matsumura, M.; Mogi, H.; Ishihara, M.; Koike, H

Abstract

The core of the multi-purpose experimental very high temperature reactor (E-VHTR) consists of the columns arranged so as to form a honeycomb structure, and each column is composed of stacked up hexagonal graphite blocks. Since the channels for coolant or control rods are provided for the graphite blocks, an upper and a lower blocks must be so positioned that the channels are aligned. For this alignment, dowel and socket joints are used. Also flange type aligning devices were developed recently particularly for limiting coolant leak. When a seismic load acts on the core, each column oscillates as a beam, colliding with adjacent columns. Therefore, the dowel or the flange area and the sides of each block are subjected to a large shearing stress and a compressive stress, respectively. The shearing stress is important in view of the material properties of graphite. Three types of the graphite fuel blocks designed for the E-VHTR were put to the breaking test by the static loading simulating seismic load. In this paper, the results of the verification of the block strength by the test and analysis are reported. The design requirement for the core components, the strength of dowel type and flange type fuel elements and so on are described. The dowel and socket strength satisfied that required by the design.

view the full text of this article (9 pages, format: PDF, size= 552kB)

key words: dynamic loads; earthquakes; fuel elements; graphite; htgr type reactors; jackets; mechanical properties; mechanical tests; planning; reactor cores; reactor materials; sleeves; stress analysis; stresses; carbon; gas cooled reactors; graphite moderated reactors; materials testing; reactor components
Reference:
Specialists' meeting on graphite component structural design, JAERI Tokai (Japan), September 8-11, 1986
International Atomic Energy Agency, Vienna (Austria). International Working Group on Gas-Cooled Reactors
IWGGCR--11, pp:99-107