Dynamic stability analysis of rock-slopes of the Sungun mine using equilibrium and numerical methods

In this paper, stability analysis of the slopes on Sungun mine was investigated. Sungun mine located in East Azerbaijan province, 45 km north of Varzaghan city. In order to investigate the stability coefficient and the rate of displacement on the slopes, three sections were selected and analyzed by numerical and equilibrium methods using SLIDE and UDEC models. The results showed that the coefficient of slope stability against failure in static conditions is more than 1.4 and in dynamic conditions with cosidering of the design based acceleration (DBA) of 0.35 g, it will be in the range of 0.92 to 1.2. In the case of applying acceleration of 0.42 g, the safety coefficient decreased to 0.8 and 1.05 and in most of the mine area, especially by Janbu method, it will be less than 1 and occurance of instability in wide range of the studied mine area is possible. However, in the extraction benches even with the application acceleration of 0.35 g, a limited chance of failure is possible. Based on the numerical analysis results, the displacements in the western part of the mine (downstream of the mine slopes) are generally higher than the eastern part of the mine. The maximum dynamic displacement in DBA of 0.42 g will be happen at section 2 (middle part of the mine) with the amount of more than 40 cm. In the entire of the mine area, the occurrence of toppling failure is dominant.