Quantifying the Risk of Construction in Landslide Prone Areas

Cut and fill earthwork activity associated with construction of highways and buildings in steeply sloping terrain through landslide deposits is difficult and involves enhanced levels of risk. Quantifying the risk of failure using conventional deterministic slope stability analyses may not adequately address the inherent uncertainties that are often encountered in these areas, which typically include significant spatial variability of the subsurface geomaterials, and geologic anomalies that may be difficult to identify in traditional subsurface geotechnical investigations. A practical reliability-based approach is described and applied to a slope failure that occurred during construction of a roadway and development near the town of Big Sky, Montana.