A Non-Destructive Method for Investigating Soil Layers of an Individual Vulnerable Slope

Abstract

Soil stability analysis becomes main concern in the preliminary design of new construction project. In a critical soil slope, the stability can be affected by the additional load and water infiltration significantly. This is due to additional overturning moment and decreasing of shear strength of the slope material. In such scenario, the non-destructive soil investigation method is needed to analyze the stability. This paper examines the use of Electrical Resistivity Tomography (ERT) to investigate soil layers in a critical slope and to measure parameters of soil shear strength indirectly. Two ERT methods used in this research were dipole-dipole array and square array resistivity (SAR). The results of ERT were verified using geotechnical testing (Bore-hole and Standard Penetration Test) results by investigating the presence of high porosity and water content with soil resistivity. The results of Dipole-dipole array and SAR at selected locations are consistent and suggest a possible crack at the location was reflected by the low soil resistivity value. Furthermore, the results of the SAR confirmed the existence of the deep crack as a continuance of visible cracks on the surface. The results of ERT can be used to detect deep cracks in the subsoil if ERT is conducted in the wet seasons, due to the existence of infiltrated rainwater. Due to the limitations of this technique, the ERT result should be interpreted cautiously. The study demonstrated the benefits of the use of electrical resistivity for the detection of soil layers in residual soil slope.

Geophysical Investigation of Groundwater Resources Using Electrical Resistivity and Induced Polarization Method

“…Geophysical surveys are one of the most reliable ways to find a groundwater supply. The common approach for the geophysical survey is resistivity method which can identify sources of groundwater potential [1]. This method is based on the composition and layering of the subsurface, interpretation of the soil's physical characteristics, and underground structures, cavities, and bodies from various geological environments [2].…”

Factors Controlling Rainfall-Induced Slope Instability of Natural Slopes in North Maleny, Queensland

“…Numerous parametric studies have been conducted on slope geometry to evaluate the effect of slope angle and height on the vulnerability of slope failures [8][9][10]. Many studies have concluded that the higher the slope angle lower both the initial and minimum factors of safety [5,11,12]. In contrast, the reduction of the factor of safety in gentle slopes is higher than that of steeper slopes at heavy rainfall [13][14][15].…”

Shear Strength of Unsaturated Expansive Soils From Queensland Natural Slopes

“…Geotechnical site investigation is of prime importance in ensuring the safety of civil engineering structures related to embankments, pavements and landfills [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Therefore the understanding of the soil interface shear strength is vital in designing and analysing the stability of geotechnical structures [15][16][17][18][19][20].…”