Structural response of large LMFBR head closures to hypothetical core disruptive accidents

A preliminary study of the dynamic response of a large (1200 MWe) pool-type deck structure to an energetic core disassembly accident was performed. The analysis proceeded as two independent, decoupled calculations: containment calculations and deck response calculations. The containment calculations were performed mainly to derive a loading pressure history for the deck structure. In part of the study, the deck was considered rigid so the derived loading pressures were conservative. In the second part of the study a set of independent deck response calculations were performed using the derived loading pressure history as input. A finite-element model that incorporated the main structural components of the deck was constructed. A preliminary study of the dynamic response of the deck was performed using this model. Also, the effect that different types of boundary conditions have on the dynamic response of the deck was studied. Based on the above preliminary studies, it is concluded that the deck structure can maintain its structural integrity under the given energy release