Dynamic parameters of seismic waves and the seismic threat to a nuclear power plant site

The hypothetical maximum effects of the so-called operating basis earthquake and of the safe shutdown earthquake should be defined for expressing the seismic threat to dimensionally and structurally complex structures which include nuclear power plants. Next to the said variables it will be necessary to take into account accelerograms corresponding to the said two types of earthquake. The objective selection of analogous accelerograms for the two types of earthquake necessitates the comprehensive knowledge of seismic wave parameters in the vicinity of the earthquake and their dependence on the earthquake magnitude and the distance from the epicentre. Relations are given of these parameters and macroseismic intensity and briefly described are other parameters obtained by statistical processing of digitalized seismic wave records. (Z.M.)