SEISMIC PROBABILISTIC SAFETY ANALYSIS OF UNIT-1 OF THE LOVIISA NUCLEAR-POWER-PLANT

The seismic probabilistic safety assessment consists of five phases. I n the seismic hazard analysis the seismicity of the plant site is quan tified. In the second phase, the structural response of plant building s is evaluated. On the basis of structural response, the seismic fragi lities of selected plant components are developed. In the following ph ase, the plant logic in the form of fault trees and event trees is est ablished. In the last step, quantification of the core damage risk on the basis of the above information is carried out. For the median valu e of the annual core damage frequency, a value of 4.4 x 10(-7) was det ermined.