Dynamic analysis of three 1000 MW WWER reactors in Eastern Europe

As part of several studies to assess the seismic safety of nuclear power plants in Eastern Europe, seismic analyses have been performed for several plants, using methods currently accepted by regulatory bodies in Western countries. This paper presents the seismic analyses performed for the reactor buildings at two nuclear power plants in Bulgaria and one in the Czech Republic. The three reactor buildings are practically identical and correspond to the standard Russian design for 1000-MW WWER reactors. The plants studied were Belene (Units 1 and 2) Kozloduy (Unit 5 and 6) in Bulgaria, and Temelin (Units 1 and 2) in the Czech Republic. For the analysis of these three plants, individual seismic input was developed from the site-specific seismic hazard for each plant. Since these reactor buildings are founded on different soil conditions and the site seismicity was different, it was expected that the structural seismic demands would be different at each plant. The structural seismic demands calculated for each of the plants were compared to assess the effects that the soil and the site-specific seismic input have on them. The in -structure acceleration response spectra at different structural components and the base forces were the structural responses selected for the seismic demand comparison in this paper. (author). 4 refs., 9 figs., 2 tabs