Effects of Non-Plastic Fines Content on Cyclic Resistance and Post Liquefaction of Sand-Silt Mixtures Based on Shear Wave Velocity

The cyclic resistance, shear wave velocity and post-liquefaction behavior of saturated Firoozkooh sand with different percentages of non-plastic silt are evaluated. Cyclic triaxial and resonant column tests performed on reconstituted samples prepared in laboratory utilizing undercompaction method. The data obtained from this study along with other existing data were transferred to the field and compared with the field performance curves based on shear wave velocity proposed by Andrus and Stokoe-۲۰۰۰. Then, to observe post-liquefaction behavior of the mixtures, volume change and pore pressure dissipation were measured. Tests results exhibit a clear trend among cyclic resistance, shear wave velocity and post-liquefaction behavior of specimens. In addition, the laboratory results indicated that using the existing field-based correlations may overestimate the cyclic resistance of the Firoozkooh sand-silt mixtures when silt content is ۶۰%. For clean sand and the specimens with up to ۳۰% fines, results of this study are fairly consistent with Andrus and Stokoe correlations. Increasing fines content would increase the final post-liquefaction volumetric strain.