Influence of freezing temperature on hydraulic conductivity of silty clay

Hydraulic conductivity of thawed consolidated slurries of a silty clay from Lashute, Quebec, Canada, subjected to closed-system freezing at different temperatures ranging from -2 to -12 degrees C were determined from constant -head permeability tests. The permeability index defined as the slope of th e relation between log k and void ratio was found to increase with decreasi ng temperature. It was also established that the ultimate permeability inde x was related to the temperature at which no further change in unfrozen wat er content occurs. For the silty clay studied, the permeability index incre ased from 1.4 for the unfrozen soil prior to freezing to a maximum value of 8 at a temperature of -12 degrees C.