EFFECT OF NON-PLASTIC FINES ON UNDRAINED RESPONSE OF FINE SAND

Abstract

Silty soils are widespread in many countries, particularly in the United States, China, and India;
hence it is essential to get an idea of the response of such soils under different forms of loading. In this paper, the
results based on undrained triaxial tests, under static as well as cyclic loading, which were carried out on the silty
sands (fine sand mixed with non-plastic fines at different percentages) are presented. The samples were prepared
at the required unit weight (Dr = 50%), saturated by using back pressure and cell pressure increments and
consolidated isotropically. Each consolidated sample is then subjected to static/cyclic loading. The results of the
static triaxial testing showed that the non-plastic fines have a significant influence on the behaviour of fine sand.
The dilation tendency decreases with the addition of fines. In the case of cyclic triaxial testing, as the fines
content increases, the rate of generation of excess pore water pressure and axial strain on cycles of loading was
found to increase and hence the liquefaction susceptibility.