Effect of Non-Plastic Fines on Liquefaction Susceptibility of Fine Sands-Paper

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The study investigates how non-plastic silt fines affect the liquefaction susceptibility of fine sand. Researchers prepared sand–silt mixtures containing 0%, 10%, 20%, 30%, and 40% fines and tested them using undrained, stress-controlled cyclic triaxial loading. Specimens were medium-dense (relative density 50%), saturated, and consolidated under an effective confining pressure of 100 kPa. Tests were conducted at a cyclic stress ratio of 0.178.<br /><br />As fines content increased, excess pore-water pressure built up more rapidly and axial strains grew sooner. The number of cycles to initial liquefaction fell from 28 for clean sand to 20, 10, 8, and 4 cycles for mixtures with 10%, 20%, 30%, and 40% fines, respectively. These results indicate decreasing liquefaction resistance with increasing silt content over the range tested.<br /><br />The authors caution that the findings are limited to one cyclic stress ratio and one confining pressure. Further testing at different conditions and at fines contents above 40% is needed to confirm the trend and identify any critical fines content.

Keywords

liquefaction susceptibility

fine sand

non-plastic silt fines

sand-silt mixtures

cyclic triaxial loading

excess pore-water pressure

axial strain

cyclic stress ratio

saturated specimens

relative density