For the new nuclear power plants, the hazard of liquefaction due to earthquakes should
be excluded by appropriate site selection or eliminated by engineering measures. An
important question is how to define a quantitative criterion for negligibility of
the liquefaction hazard. In the case of operating plants, liquefaction can be revealed
as a beyond-design-basis event. It is important to learn whether the liquefaction
hazard has a safety relevance and whether there is a sufficient margin to the onset
of liquefaction. The use of pseudoprobabilistic method would be practicable for the
definition of probability of liquefaction, but it could result in overconservative
results. In this paper, the applicability of the pseudoprobabilistic procedure is
demonstrated for the sites in diffuse seismicity environment and for low hazard levels
that are typical for nuclear safety considerations. Use of the procedure is demonstrated
in a case study with realistic site-plant parameters.
