ABSTRACT
The application of reliability theory for slip circle analysis of earth and rockfill dams is described using the First-Order Second-Moment method and stresses calculated from non-linear finite element analyses. The limit state function was formulated from the definition of a finite element safety factor based on shear stress. Representative statistical data for the fill materials were obtained from analyses of experimental and field data of the material properties in three existing dams. A reliability analysis was carried out for the upstream slope for the “end-of-construction” stage of an earth and rockfill dam. Six slip circles were used in the analysis, and comparison of their probability of failure and safety factor showed that the order of criticalness of the slip circles predicted by the latter can be misleading. In addition, the overall system probability of failure is close to that of the most critical circle. Sensitivity studies were carried out on the six slip circles to investigate the effects of progressive introduction of correlation between the properties.
