Slope Monitoring Study using Soil Mechanics Properties and 4-D Electrical Resistivity Tomography Methods

摘要

In past applications of electrical resistivity survey, users commonly focussed on theudEarth's subsurface to locate water table, bedrock, etc. Nowadays, this electrical resistivityudmethod is used by engineers for shallow subsurface investigations. This paper presentsudthe integration of soil mechanics properties with electrical resistivity tomography methodsudand recommends the proper selection of resistivity array (survey planning) and appropriateudinversion constraint parameters (data processing) that are able to deliver optimumudresistivity tomography model results. This study identifies the empirical correlations ofudthe soil's properties such as shear strength parameters, moisture content, void ratio,udporosity, saturation degree, and Atterberg's limits with the electrical resistivity valuesud(resistivity tomography models). A total of 11 undisturbed clayey sand soil samples wasudcollected at different distances, depths, and times and were tested under both infield andudlaboratory conditions during the slope monitoring period. The soil mechanics propertiesudof the soil samples were obtained right after the electrical resistivity survey was made. Itudis shown that the electrical resistivity values are greatly influenced by the soil mechanicsudproperties. Thus, the electrical resistivity (4-D) survey using the optimized Wenner-udSchlumberger array (high data density) is capable of reliably enhancing the conventionaludoutcome of the Earth's subsurface investigation