Sensitivity analysis of nickel haul road embankment slopes using the coefficient of variation approach

Purpose. The behavior of slope instability is influenced by many factors, both internal, such as the physical-mechanical properties of materials, and external, such as rain and seismic activity. Sensitivity analysis is used to determine the parameters that have the greatest impact on the level of slope stability. Methods. Sensitivity analysis of embankment slopes uses the coefficient of variation (CV) approach with input parameters namely cohesion and internal friction angle. Findings. The results of the study confirm that the internal friction angle is the most influential parameter on the embankment slope stability. The evidence is that at the highest percentage of CV, there is the highest probability of avalanches, based on these parameters. Originality. In this research, the coefficient of variation method is used to determine which parameters have heterogeneous data distribution and the greatest probability of failure, as well as to test mechanical sensitivity with the concept of changing the percentage of parameters to a safety factor value to validate calculations using the coefficient of variation approach. Practical implications. The sensitivity analysis results are not only limited to values, since the more important is finding out the cause of the influence of these parameters according to field conditions. The reason why the internal friction angle is the most sensitive parameter is the grain size approach, when the limestone mixture in the field has coarse and large grain sizes. Therefore, the surface tends to form rough waves and causes the relatively large grained rocks to have large internal friction angles.