Risk analyses of three Norwegian rockfill dams

The application of risk analysis to dam safety is illustrated by assessments performed for three moraine-core rockfill dams that together are representative of many such structures in Norway. Hydrologic, seismic, and normal loading conditions are addressed, with emphasis on internal erosion aspects. It is shown how risk analysis performed an important diagnostic function by identifying significant risk contributors while also confirming the safety of these dams as a class. Specific factors that enhance reliability are identified and their contributions quantified probabilistically.