Evaluation of Limit Equilibrium and Finite Element Methods in Slope Stability Analysis - Case Study of Zaremroud Landslide, Iran

Document Type : Original Article


1 Assistant professor; Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Ph.D. Student; Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran


The events that result from slope instability that causes a mass of soil to move downward from an earth slope (landslides) are studied in this research. The most important factors of slope instability are the force of gravity and the presence of water, which cause soil erosion at the surface and increase pore pressure at greater depths, thereby reducing soil strength. Iran, with mainly mountainous topography, tectonic activities, high seismicity, and diverse geological and climatic conditions, has the susceptible to landslides. Therefore, the analysis of slope stability and its safety evaluation is crucial in this region. Choosing the right method for sustainability analysis, which is one of the engineers' challenges in estimating the sustainability of a slope, depends on the project conditions and the inherent limitations of each method. This paper presents a case study of the stability analysis of a soil slope using limit equilibrium and finite element methods in Zararmood region in Mazandaran Province of Iran. The results show that the safety factor calculated by the finite element method is about 3% lower than the limit equilibrium method which is negligible due to the simplicity of calculations in the limit equilibrium method.


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