Experimental Analysis of Resistivity Changes and Wetting Deformation of Soil−Rock Mixture

Abstract

A nondestructive technique is lacking for the quick and accurate detection of wetting deformation in field measurements. In this study, we investigated the feasibility of using resistivity to assess wetting deformation. A modified triaxial apparatus was used to conduct wetting tests on a soil−rock mixture (SRM), with simultaneous measurement of resistivity and deformation. The results indicate that resistivity gradually decreases during consolidation and that the magnitude of resistivity changes is affected by the rock content and confining pressure. The resistivity values exhibited a gradual decrease during shearing, with the magnitude of this decrease showing a negative correlation with the rock content. In addition, there was a positive correlation between the rate of deformation and the rate of change of the resistivity. The resistivity in the wetting tests was divided into three distinct stages: prewetting, during wetting, and postwetting. Throughout these stages, a consistent decrease in resistivity was observed. The inflection points observed in the resistivity–axial strain curve can be used to determine the beginning and end of wetting. A mathematical model based on the exponential function is proposed for assessing wetting deformation via resistivity measurements. The experimental results verify the feasibility of real-time monitoring and evaluation of wetting deformation using resistivity.