The four faults that controlled the slope failure are shown. Geological sketch map of slope failure area. A geological map of the area was available, as shown on Figure 2.įigure 2. Geological mapping of the pit face showed that the rock mass involved with the failure was bounded by four faults. We show by our study of this open pit mine failure that there can be a significant difference between factors of safety calculated using 3D and 2D analyses. Stability analyses can also be carried out in 2D, using arbitrary sections drawn across the 3D model. The failure surface can be any shape, such as formed by interconnecting fault surfaces as in this open pit mine failure. TSLOPE is able to carry out 3D limit equilibrium analysis of columns overlying a shear failure surface. We have taken the relevant data, and developed a three dimensional slope model using TSLOPE, an innovative software package for slope stability analysis. Photograph of pit area involved with slope failure. The failure as shown in Figure 1, involved three benches at an intermediate slope that was being pushed back towards the final high wall location.įigure 1. In 1996 a slope failure occurred at the Round Hill open pit mine, operated by Macraes Mining Company Ltd.
