Application of Resistivity Measurement to Stability Evaluation for Loess Slopes

The aim of this study was to convert a resistivity field into a local factor of safety (LFS) field in order to capture the characteristics of the water infiltration and slope failure processes in loess landslides. The generalized earth pressure coefficient and the LFS were introduced, and a method based on the monitoring of the resistivity field was proposed. An improved electrical resistivity tomography (ERT) method was then adopted. The water infiltration and the distribution of water inside the slope were analyzed using the slope sequence resistivity field for two rainfall scenarios. The validity and the physical justification of the proposed method were then verified. The results were as follows: (i) the proposed method could effectively capture the failure location and the instability process of the slope. (ii) Although the proposed method ignored the heterogeneity of the slope body, when the migration process and the distribution characteristics of the water within the slope under two rainfall scenarios were clearly presented, the conversion from the slope resistivity field to the soil moisture content (SMC) field was theoretically feasible. (iii) The uniform infiltration pattern induced the shallow landslides or mudflows with long-term light rainfall. Middle and deep loess landslides were easily induced by the significant preferential infiltration phenomenon with short-term heavy rainfall. The proposed method is very important for the early identification and risk mitigation of water-inducing landslides in loess areas, and it is helpful for developing a deeper understanding of the preferential flow within soil.