Stability of earth-rockfill dams: Influence of geometry on the three-dimensional effect

A series of parametric studies were performed to investigate the three-dimensional (3D) effect on the stability of an earth-rockfill dam, with respect to some major factors, such as geometrical characteristics of the dam and topography of the canyon. The length-height ratio of the earth-rockfill dam clearly influences the 3D safety factor. A power function suitably expresses the relationship between the increment ratio for the safety factor and the length-height ratio. The canyon shape, gradient of dam slope and height of the dam significantly influence the 3D effect. The results may be used as a blueprint by combining the two-dimensional (2D) safety factor in common use, and the relationship between 2D and 3D safety factors established in this study.