Viscometric assessment of remoulded sensitive clays

Abstract

Remoulded samples of sensitive clay, from Gloucester and St. Jean Vianney (SJV), have been assessed by viscometric techniques. The results complement geotechnical and mineralogical data and they permit the differences in sensitivity to be discussed in terms of the remoulded clay properties. The SJV clay (St > 200) exhibits dilatant flow properties and the Gloucester clay(St ~ 20) has Bingham plastic characteristics. The properties of the latter are a function of clay mineralogy and pore-water chemistry; they contribute to the remoulded strength and thereby restrict sensitivity. The response of the clays to a changing chemical environment is monitored; increasing the cation concentration of the pore water transforms the SJV clay to a Bingham plastic; a maximum yield stress for the Gloucester clay is attained at pH ~ 6.5. The correlation between viscometric data and related field investigations suggests that this analytical approach may provide a suitable basis for the fundamental study of soil behaviour, soil characterization, and the design of electrochemical ground treatments.