Reanalysis of the floor response spectra of the Ignalina Nuclear Power Plant Reactor Building

The seismic input is evaluated on basis of the seismotectonic data and seismic properties of soil of the Ignalina NPP site. The dynamic finite element analysis of the reactor building was conducted in two stages. The soil-structure interaction analysis was carried out in order to assess the effects of the soil on the input spectra by applying two quasi two-dimensional coupled soil-structure finite element models. A detailed three-dimensional model of the building structure was developed for the fixed base dynamic analysis. The floor response spectra were obtained at the specified levels and specified points of the building. The influence of 3D effects and specific properties of the building structure are comprehensively discussed.