Simplified Approximation Procedure for Performance-Based Evaluation of Liquefaction Potential

Abstract

Performance-based procedures for evaluation of liquefaction potential have been shown to provide more consistent and accurate indications of the actual likelihood of liquefaction in areas of different seismicity than conventional procedures. The process of performing a complete site-specific performance-based evaluation of liquefaction potential, however, requires numerous calculations involving quantities that many geotechnical engineers are not familiar with. This paper shows how the results of complete performance-based analyses can be expressed in terms of a scalar parameter corresponding to a particular element of soil in a reference soil profile, and presents procedures for adjustment of that parameter to account for site-specific conditions that differ from those of the reference profile. The procedures are shown to closely approximate the results of complete site-specific performance-based evaluations. Engineers can then use mapped values of the scalar parameter, along with the recommended adjustment procedure, to realize the benefits of a performance-based evaluation without having to actually perform the performance-based calculations.