On the use of a fractal equivalent circuit model to predict the geotechnical properties of soils
Frequency dependent electrical measurements of soils contains useful information about their texture and structure that can be linked to their geotechnical and transport properties. We perform frequency dependent electrical measurements on twenty-nine natural soils with wide variability in physical and textural properties in a laboratory environment at a constant stress level in the frequency range 0.01Hz -10 kHz. The engineering and hydraulic properties of these soils, that is, the hydraulic conductivity, void ratio, fines content, intergranular void ratio and the dry density are also measured. The electrical behavior of the soils were modeled with an equivalent circuit model described by six circuit parameters. Relationships between the circuit parameters and the soil properties (geotechnical engineering and hydraulic) are investigated. Crossplots of frequency exponent (ç) and resistivity (ñ0 ) and that of ç and är clusters soils with high and low permeability, whiles crossplots of relaxation time (ô) and ñ0 clusters soils with high and low intergranular void ratio. The parameters ç and är are used in regresions equation to reasonably predict permeability.
