Effect of Salt Solution on Plasticity and Permeability of Vietnam's Soil Liners

In Vietnam, there are a lot of landfills to block pollutants and one of materials used for impermeable liners is soil liners (soil – bentonite mixture). In order to use as impermeable liners, the properties of soil liners such as plasticity and permeability were affected by many salt solutions which are leaching from decomposition of waste materials in the landfills. Those salt solutions can reduce the stable of impermeable liners. So, this paper presents a series of experimental studies in the laboratory to investigate the effect of some salt solutions on the properties of compaction, consolidation and plasticity of soil liners. The experimental results indicated that the salt concentration effected complex on the Atterberg limits and the vertical coefficient of permeability. It also found that increase in the salt concentration from 0N to 0.05N cause increase in plasticity index, liquid limit and decrease in the vertical coefficient of permeability. After that, the increasing of the salt concentration up to 1N resulted in decrease in the liquid limit and plasticity index and increase in the vertical coefficient of permeability increases.