The electrical resistivity characteristics of compacted clays

This technical note describes work carried out on the electrical resistivity characteristics of a clay-water electrolyte system. The samples were tested over a range of consistency indices and at varying degrees of compaction. Resistivity/fractional volume of water relationships have been established for two different clays, a Cheshire clay and a London clay, over a practical range of moisture contents. A unique relationship exists between these parameters for each clay. The resistivity of a clay is a function of moisture content and degree of saturation. At a particular moisure content, an increase in the degree of saturation (or a decrease in the air-void ratio) will mean a decrease in resistivity. (TRRL)