SLOPE DESIGN OF AN OPEN-PIT COPPER MINE

The stability of a copper open pit slope was investigated by the limit equilibrium method. Further analysis was done by numerical modelling technique. The results from both methods were found to be in agreement. In the course of the study, geotechnical mapping was undertaken to determine the critical orientation of geological discontinuities. Geomechanical properties were determined in the laboratory. Sensitivity analysis was conducted to determine the parameter which will influence the slope performance the most. It was also used in determining the most suitable remedial measure for the critical slope. Presplit blasting was experimented successfully for creating a stable final pit slope. The analysis by the limit equilibrium method and numerical modelling of the open pit slopes indicate that the 148 m deep open pit is stable with a 60-degrees overall slope angle. Slope monitoring did not reveal any movement in and around the pit.