Evaluation of Stability of Cutslopes in Open Cast Metal Mines Using Numerical Modelling and Field Monitoring

Evaluation of Stability of Cutslopes in Open Cast Metal Mines Using Numerical Modelling and Field Monitoring

S. Jayanthu Guntha Karthik

Mining Engg Dept., NIT Rourkela, Odisha, India

Corresponding Author Email: 
4 March 2018
18 April 2018
31 March 2018
| Citation



Slope failure is one of the biggest concerns in the opencast mines in the mining industry. Monitoring information about the slopes is used for various aspects such as current mining plan evaluation, designing of future slopes and its safety control. Proper designing of slopes is crucial for its stability but in spite of how well it’s designed is, it’s susceptible to slope failure because of unidentified geological structures, unexpected weather conditions, or seismic activities, etc. So continuous monitoring of slopes is needed to ensure stability. In this paper Slope, stability monitoring was performed in Mine-A. The entire mine has several cut slopes made to have the passage for the conveyor belts. The field study was done in Nine locations of Mine-A. The monitoring was done with the total station and the data was compared for the two consecutive studies to find any movement. In displacement analysis, it was found that the change in displacement varies from 0-5cm from May 2015 to Feb 2016 for most of the area in the mine except the deep cut areas which have the variation of up to 9 cm in some places. The slopes are stable, but slopes in the deep cut area are moving very slowly. So, periodic monitoring is necessary for the area. The numerical modeling in this study was done with Fast Lagrangian Analysis of Continua (FLAC) Slope and Oasys softwares to find the Factor of Safety (FOS). With FLAC Slope, the value of FOS was in the range of 1.3-1.51 while Oasys slope gave the value of FOS in the range of 1.39 -1.71. The result of the graphical analysis, as well as the numerical modeling, indicates that the slopes are stable since FOS values are well above one.


slope stability, factor of safety, displacement, FLAC, oasys

1. Introduction
2. Description of Study Area
3. Displacement Analysis
4. Laboratory Analysis
5. Numerical Modelling of Slopes
6. Conclusion

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