Estimation of the viscosity of clay suspensions

Slurry walls are often used in geo-environmental applications for lowering the ground water table, barriers for contaminant migration, etc. Estimation of the viscosity of clay suspensions is important for the installation of slurry walls. Further, the knowledge of the viscosity of dense clay suspensions aids the devising of suitable visco-elastic and visco-plastic models for the response of such systems to changes in stress. Several equations are available in literature for estimating the viscosity of suspensions of solid bodies. The equations fall into two categories: those which neglect the presence of an electrical surface charge on the suspended bodies and also ignore the actual size of the individual bodies, and those equations which provide for these features and also for the conductance of the fluid to play a role. This study identifies the equation that is best suited for slurry walls and for devising models for clays.