Guide for Shear-Wave-Based Liquefaction Potential Evaluation

Abstract

Small-strain shear-wave velocity measurements provide a promising approach to liquefaction potential evaluation. In some cases, where only seismic measurements are possible, it may be the only alternative to the penetration-based approach. Various investigators have developed relationships between shear wave velocity and liquefaction resistance. Successful application of any liquefaction evaluation method requires that procedures used in their development also be used in their application. This paper presents detailed guidelines for applying the procedure described in Andrus and Stokoe that was developed using suggestions from two workshops and following the general format of the Seed-Idriss simplified procedure. Correction factors to velocity and liquefaction resistance for soil aging are suggested. Based on the work by Juang et. al., factors of safety of 1.0, 1.2, and 1.5 correspond to probabilities of liquefaction of about 0.26, 0.16, and 0.08, respectively. Additional field performance data are needed from all soil types, particularly denser and older soil deposits shaken by stronger ground motions, to further validate the recommended procedure.