Geotechnical centrifuge modeling of chloride diffusion through soils

Abstract

Geotechnical centrifuge modeling provides a means of accelerating the transport of contaminants through a soil matrix. Contaminant transport mechanisms occurring in the geotechnical centrifuge model can be used to verify various mathematical and analytical models. This technical note presents modeling of chloride (Cl) diffusion through soils in a geotechnical centrifuge. Acceleration level, N, of 100 g was used for centrifuge modeling of Cl migration through 7.5-m-deep soil strata for a period of 150 and 600 days. From the centrifuge test results, the Reynolds number, R, and Péclet number, P, were found to be several orders less than unity. This indicates that the dominant Cl transport mechanism in the soil is diffusion. Finite-element modeling was performed, using SEEP/W and CTRAN/W, to validate the experimental results, and excellent matching has been obtained. The study also highlights that geotechnical centrifuge modeling can be used as a viable alternative to field scale experimentation.