Effects of Soil Properties and Slope Angle on Deformation and Stability of Cut Slopes

Abstract

The impact of soil parameters and slope angle on the deformation and stability of cut slopes is critical for defining road project safety measurement. This study investigates the effect of soil properties and slope angle on the deformation and stability of cut slopes in general and the specific Arba Minch-Chencha upgrading road project. Forty-eight (48) analyses were carried out both in Slope/W and Plaxis 2D software for six cut slopes and analyzed for four different slope angles. Twenty-four (24) dataset samples were collected from six different cut-slope sites. These dataset samples were categorized in two situations, i.e., before and after water saturation for each cut slope. The limit equilibrium method (LEM) comparison clearly showed that the Spencer, Bishop, and Morgenstern-Price methods produced similar FOS. The Ordinary and Janbu approaches, on the other hand, underestimate the FOS. Most LEMs except Ordinary and Janbu methods that estimated higher FOS than finite element method (FEM) analysis. It is observed that the main reasons for the cut-slope instability were the provision of steep cut-slope angles, the existence of a high proportion of fine soil, and moisture content, which was observed in both Plaxis 2D (FEM) and Slope/W (LEM). It was concluded that the slope is more stable for the soil having few fine-grained fractions. Moreover, flattening the slope stabilizes the cut slopes based on the results obtained from both Plaxis 2D and Slope/W.

Factors affecting the oedometric modulus of till soil

“…Soil is less deformable when it contains less fine fraction (Habtemariam et al 2022). Grain size and its distribution in soil are the determining factors of sandy soils' deformation.…”

“…The understanding of the existing correlation between these soil properties is essential for working out practical application solutions. As highlighted by numerous researchers, an increase in water content leads to a decrease in soil strength, deformation modulus value, coefficient of consolidation (C v ), and the angle of internal friction (φ) (Malizia, Shakoor 2018;Habtemariam et al 2022;Hov, Gaharia 2023). Some research indicates that compressive strength of soil increases with clay plasticity (Malizia, Shakoor 2018).…”

Exploration and research on ammonium free green leaching agent for ionic rare earth ore and influencing factors of soil slope stability

“…Through the continuous exploration and practice of many scholars and engineers, three generations of mining technologies have been developed for ionic rare earth ores: pool, in-situ smelting, and sediment leaching. Ammonium-free green leach leaching without mining the deposit, with low environmental impact and low production cost, has become a widely recommended mining method for ionic rare earth mines at present (Habtemariam et al, 2022). However, some problems have emerged during the 20 years of development of ammonia-free green leaching, among which the prominent ones are geological disasters such as landslides caused by the improper injection, as shown in Fig.…”