Optimization of seismic protective system for the Kalinin NPP primary circuit

Technique and results of calculation of seismic protection for the Kalinin NPP first unit are given. The calculations were performed according to Kupol and Kolos programs with provision for interaction of structure and ground base for different amplitudes of vibration acceleration. Structure reactions (pressurizer, condensation pool, primary circuit pipes, main recirculation pumps and ECCS) to seismic effects were calculated. The calculations performed made it possible to reduce the number of hydraulic shock-absorbers as compared with the initial project