Reliability Analysis of Embankment Dams

The reliability analyses of one rockfill embankment dam in Norway are presented. The event tree analysis and the Bayesian network approaches, the latter combined with Monte Carlo simulations, were used to obtain the annual probability of dam breach. The analyses were run partly in a workshop format, as a process to reach consensus among several experts on the parameters to consider in the calculation of probabilities. The analyses illustrate that the reliability analyses enabled the identification of an unexpected mode of failure and later quantified the effect of rehabilitation measures on the estimated probability of dam breach.