In this study, ion seepage tests were conducted by using fine-grained soil with permeability coefficients (
k) ranging from 1.0*10
-6 to 1.0*10
-10 m/s. In the tests, density flow and molecular diffusion were induced by giving the concentration gradient but not the hydraulic gradient to investigate the parameters affecting the movement of fine-grained soil in an inverse problem approach. Numerical analyses were also performed to evaluate the barrier performance of the fine-grained soil. The study revealed that (1) the permeability coefficient
k of a bentonite-soil mixture and the effective diffusion coefficient
Dd* are dependent on effective porosity
ne, (2) it may be possible to estimate the effective porosity
ne of a bentonite-soil mixture and the effective diffusion coefficient
Dd* with relative ease from the consistency limit and (3) there is a considerable diff erence in barrier performance betwee n a 5.0-meter-thick soil layer (barrier layer) with a pe rmeability coefficient
k of 1.0*10
-7 m/s and a 0.5-meter-thick barrier wall with a permeability coefficient
k of 1.0*10
-8 m/s.
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