Assessment of Cone Penetration Resistance for Liquefaction Potential Evaluation

Saturated soils lose a significant amount of their strength and stiffness when subjected to cyclic loadings generated by earthquakes, and often behave like liquids during shaking. Liquefied soils have proven to be damaging to foundations of buildings, dams, bridges, and roads. Recent investigations have indicated that cleaner sands, which are sands with little to no fines, have a resistance to liquefaction that is different than sands with fines. These observations are contrary to the results in the present form of liquefied potential evaluations used by engineers. The purpose of this study is to experimentally verify the cone penetration test (CPT) based liquefaction evaluation curves currently used in practice as well as determining the effects of fines on a soil’s resistance to liquefaction. CPTs were performed on laboratory samples of sand with varying fines content to examine the effects of fines on the CPT resistance. These results were combined with previously conducted cyclic tests on the same soils for evaluating the liquefaction evaluation curves. Although criteria for examining potential for liquefaction of soils already exist, there should always be new ways to improve the accuracy in currently practiced methods. The smaller scale soil samples, although are an idealistic representation of field conditions;  allow evaluation of the accuracy of the current liquefaction assessment curves by eliminating variability from field observations on which the curves are based on. The increased accuracy in liquefaction assessment will help improve seismic analysis in the designs of infrastructure, even though earthquakes are unpredictable phenomena.