Application of a geotechnical centrifuge for estimation of unsaturated soil hydraulic conductivity

Contamination of the groundwater regime and subsurface soils is one of the major problems that has arisen due to rapid industrialization. Spread of co ntaminants in the unsaturated soil strata, mainly close to the ground surfa ce and lying above the water table, depends on the hydraulic conductivity o f the soil. As such, estimation of unsaturated soil hydraulic conductivity becomes very important. However, it is quite difficult to estimate the same in a reasonable amount of time, due to the very low hydraulic conductivity of unsaturated soil. The potential of a geotechnical centrifuge for modeli ng various geoenvironmental engineering problems being very well establishe d, an effort has been made to obtain the unsaturated state of a silty soil, starting from its saturated state, by centrifugation. The soil water chara cteristic curves obtained have been used for determining the unsaturated so il hydraulic conductivity.