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Dips Stereographic Projections <br /> ' The Dips software was used to develop stereographic projections and perform planar sliding, <br /> wedge sliding, and flexural bending analyses. The stereonets produced for this evaluation are <br /> ' shown in Figures 3, 4, and 5 included at the end of this report and show a large distribution of <br /> discontinuities, which was anticipated due to the large dataset. The analyses are performed by <br /> evaluating whether the poles of the discontinuities fall within the critical area on the stereonets, <br /> which are defined by the orientation of the discontinuities(dip and dip direction)and their friction <br /> t angle. The poles that plot within the critical areas are considered kinematically admissible for <br /> failure, and the output of the analyses gives an indication of the percentage of surfaces that are <br /> susceptible to failure based on the geometry of the excavation. Results of the stereographic <br /> ' projections are summarized in Table 3. <br /> Kinematic Analysis Pole vector concentration <br /> ' Planar Sliding 7.3% <br /> Wedge Sliding 21.4% <br /> Flexural Toppling 15.7% <br /> These results indicate that the roadcut has a high probability of encountering kinematically <br /> unstable blocks. In relative terms, the wedge sliding failure is the most likely to occur. <br /> ' SWedge Failure Analysis <br /> ' Wedge failures occur when discontinuities intersect in an orientation that creates an unstable block <br /> or "wedge" capable of sliding into the excavation. The Swedge software from RocScience <br /> computes possible combinations of discontinuity intersections which can form a wedge, and <br /> ' develops a minimum factor of safety for each wedge.The analysis assumes translational slip based <br /> on discontinuity orientations, slope height, rock unit weight, and joint strength. No external <br /> pressures (water pressure and seismic)were applied for this evaluation. <br /> ' Result of the wedge failure analysis showed more than 35,536 possible wedges could form based <br /> on the dataset. A factor of safety is assigned to each wedge, and the results show that 76%of these <br /> wedges having failure potential with a factor of safety less than 1.0. Results of the wedge failure <br /> ' analysis are show in histograms and as a scatter plot in Figure 6 and 7. <br /> RocTopple Analysis <br /> Toppling failure occurs when the discontinuities within the mine highway are near to parallel with <br /> the slope of the face, creating a parallel series of slabs that can topple into the excavation. Using <br /> ' an excavation trend and discontinuity characteristics, RocTopple can compute all discontinuities <br /> which can form a parallel series of slabs and develop a minimum factor of safety for each series <br /> of slabs. The RocTopple model analyzes when slabs will slide as a mass and which slabs will <br /> topple.The model can also identify if any of the slabs will be in tension during a toppling failure. <br /> The main input for RocTopple is the geometry of the slope and structural discontinuities, as well <br /> as the strength of the joints. The software is best used with site-specific information such as joint <br />