Slope failures evaluation and landslides investigation using 2-D resistivity method

Abstract

Slope failure is a complex phenomenon that may caused to landslides. Buildings and infrastructure such as transportation facilities and pipelines located within the boundaries of a landslide can be damaged or destroyed. Slope failure classification and various factors contributing to the instability using 2-D resistivity survey conducted in Selangor, Malaysia are described. Six 2-D resistivity survey lines with 5 m minimum electrode spacing using Pole-dipole array were performed. The data were processed using Res2Dinv and surfer10 software to evaluate the subsurface characteristics. The 2-D resistivity results show that the subsurface consist of two main zones. The first zone was alluvium or highly weathered with resistivity value of 100-1000 O m and depth of >30 m. This zone consists of saturated area with resistivity value of 1-100 O m and boulders with resistivity value of 1200-7000 O m. The second zone with resistivity value of >7000 O m was interpreted as granitic bedrock. The study area was characterized by saturated zones, highly weathered zone, highly contain of sand and boulders that will trigger slope failure in the survey area. This will cause to low strength of soil, debris flow and movement of earth. On the basis of the case examples described, 2-D resistivity method is categorized into desirable and useful method in determination of slope failure and future assessments.

Analysis of Geotechnical-Assisted 2-D Electrical Resistivity Tomography Monitoring of Slope Instability in Residual Soil of Weathered Granitic Basement

“…There is also presence of high resistivity >4,000 Ωm located beneath the surface interpreted as boulder indicated with dashed blue line in Figure 9. Saturated zones were located beneath and beside some of these boulders ( Figures 9C-F), which may induce movement during heavy and prolong rainfall (Nordiana et al, 2018a). The continuous infiltrated of water from the prolong rainfall will lead to oversaturation of the cohesive soils within the saturated zones, and it can cause a reduction in the cohesive forces of the soils resulting in the soil particles to be separated from each other by a small infinitesimal distance delta x, and when this happened, their shear strength will not be fully contributed by cohesive force but by internal friction.…”

“…In Peninsular Malaysia, shallow landslides are common occurrence that have been studied using 2-D ERT as reported by several researchers (Abidin et al, 2017;Ismail and Yaacob, 2018;Nordiana et al, 2018a;Nordiana et al, 2018b). However, a reliable method to include density in geotechnical calibration of ERT model resistivity values distribution is still rare.…”

Mathematical Modeling of the Water Saturation Algorithm of the Mountain Slope on the Example of the Catastrophic Landslide of the Northern Tien Shan Ak Kain

“…Malaysian researchers, Nordiana et al [12], using the 2D resistivity method, were able to determine the structure of the slope layer in the Selangor of Malaysia. It turns out that the soils of this slope are formed of sand with boulders.…”

“…Elastic properties of soils and their layers' thicknesses on the path of the foothill territory of the city Almaty[10] PhMP and strength properties of anisotropic structure soils[12] …”

Soil Shear Strength Parameter Analysis Based on Behavior Analysis of Landslide Case

“…Slope failure is a complex phenomenon that causes landslides and results in severe infrastructural, social, and economic damage. The prevalence of slope failure is caused by a combination of several factors, namely topography, climate, geology, and land use [1]. When a slope slides, there is a lot of useful information about the conditions of the Slope at the time of collapse as well as the opportunity to validate the existing stability analysis methods [2].…”