The influence of silt content on liquefaction strength of sands

Several series of undrained monotonic triaxial tests are per-formed on reconstituted saturated samples of Ardebil sand with variations in the fine contents, in order to clarify the effect of fine contents on the behavior of sand during liquefaction. The samples are made up of sand and silt with silt content ranging from 0% to 100%. The specimens are prepared into the loosest state using undercompaction method of preparation. This study shows, as the silt content increases up to 35%, the contractiveness is increased and the peak and residual strengths are decreased and the steady-state lines move downwards. With the further increase in silt content, the peak and residual strengths are increased and the steady-state lines move upwards. However, the steady - state lines of silty sand and pure silt are well under the lines of clean sand.