Probabilistic analysis for liquefaction

A comprehensive review of liquefaction case histories was made and an expanded data set was prepared. The newly compiled field data are presented together with a criterion for liquefaction based on the field observations of liquefaction and nonliquefaction. A simple model for calculating the probability of liquefaction conditional to the occurrence of a particular seismic event is given. Applications of the proposed criterion and the probability model are discussed and comparisons are made between the results of this research and those previously published. Specific applications of the proposed method include an evaluation of overall liquefaction risk at a site and estimation of earthquake-generated excess pore pressures. It is concluded that liquefaction analysis procedures, which are invariably based on field observations, include significant uncertainties because of the imperfect nature of the data used. Use of the probability model presented herein permits proper evaluations of these uncertainties.