Document Type : Original Research Paper

Authors

1 Department of Mining Engineering, si.c, Islamic Azad University, Sirjan, Iran

2 Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran

10.22044/jme.2025.15867.3055

Abstract

The slope geometry, rock mass quality, groundwater level, and geological features of the mine mainly influence the slope stability of an open-pit mine. In this study, the stability analysis of the open pit slope under the influence of various factors was studied. The analysis was conducted based on data collected from the Golgohar iron ore mine in Sirjan. To build the numerical model, first, the geomechanical and hydrogeological parameters of the mine were determined using laboratory and field tests. Then, numerical models of slope stability were built based on the finite difference method using hydromechanical coupling analysis. The real characteristics in these models include lithology types, variations in geomechanical properties, groundwater level, and real slope geometry. Numerical models were built based on three different conditions, including a model in dry conditions, a model considering the groundwater level, and a model after the drainage process. The results show that the whole slope angle of the mine that has the highest safety factor is 36 degrees. In addition, the groundwater level reduces the safety factor of slope stability compared to dry conditions, and the drainage process can increase the safety factor of the mine wall. In all three conditions, the whole slope angle of 36 degrees has the highest safety factor. Therefore, it is suggested that the whole slope angle be considered to increase the safety factor and reduce the stripping ratio to increase the profitability of the open pit mine.

Keywords

Main Subjects

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