Comparing CPT and Vs Liquefaction Triggering Methods

Significant developments have taken place over the past 20 years to evaluate the liquefaction potential of soils using in situ tests. The cone penetration test (CPT) is now commonly used to evaluate liquefaction potential in soils. There have also been significant developments to evaluate liquefaction potential based on in situ shear wave velocity (Vs) measurements. Liquefaction methods base on shear wave velocity have the advantage that they are essentially independent of soil characteristics, such as fines content, but often lack the stratigraphic detail obtained using the CPT. Liquefaction methods based on the CPT have the advantage of continuous, repeatable measurements but require corrections based on soil characteristics that can be significant in soils with high fines content. Comparing the most recent Vs-based method with a CPT-based method provides an independent evaluation of the associated corrections applied to the CPT-based method. This paper compares the current Vs-based method with a specific CPT-based method from the literature to evaluate the associated CPT-based corrections. The paper also examines the advantage of using both CPT and Vs measurements (e.g., using the seismic CPT) to evaluate liquefaction potential.