Floor Response Spectra of Loviisa NPP Reactor Buildings

For the updated seismic probabilistic risk assessment of the Loviisa nuclear power plant in Finland, knowledge of reactor building floor response spectra were needed. For this purpose a large finite element (FE) model of the reactor building was constructed. The model included all the major primary circuit components. The FE -model was parameterized and the Latin hypercube method was utilized to construct sixty samples of reactor building. Parameters used were material properties for concrete and steel, modal damping and the ground motion. The ground motions were derived from the seismic studies conducted for the Loviisa site. Following results were achieved in this analysis: The probabilistic spectra were determined for different elevations in the reactor building as well as for the representative locations in the main mechanical components that were explicitly modeled.