Electrical Resistivity-Based Characterization of Geotechnical Properties of Mine Tailing

Abstract

Electrical resistivity technique is gaining a lot of significance in the geotechnical engineering field due to the advantages it offers such as non-destructiveness, cost-effectiveness, and rapid investigation of subsurface soil properties. The electrical resistivity is an intrinsic soil property and is considered to be representative of various geotechnical properties such as mineralogical composition, pore fluid conductivity, surface conductivity, particle size, fine content. The present study includes the measurements of electrical resistivity of the mine tailing using the laboratory-based four-electrode method. This paper explores the effect of various geotechnical characteristics of partially saturated and saturated tailing samples and aims at developing the correlations between resistivity and geotechnical properties. Controlled laboratory experiments were conducted to study the variation of resistivity with moisture content, compaction density, porosity, degree of saturation, temperature, and type of pore fluid. The electrical resistivity was found to be influenced by changes in the water content, degree of saturation, dry density, and other listed properties for sample prepared under partially saturated condition. Also, the rigid wall variable head permeameter was equipped with electrodes to enable measurements of electrical resistivity while simultaneously measuring the permeability of saturated tailing samples. The resistivity of tailing samples was found to be related to saturated permeability. The electrical resistivity values of tailing sample under the loosest and densest conditions lie within range of 70 Ω m–5 Ω m. The resistivity of mine tailings was also compared with the fine sand and found to be lower than sand due to traces of particles of metallic origin. The present work may be useful for robust estimation of in situ characteristics of tailing and soils, in general, by means of electrical resistivity surveys and may thus help in preventing the failure conditions by monitoring the changes in geotechnical properties under prevailing conditions.KeywordsElectrical resistivityMine tailingPermeabilityFour-electrode method