Influence of Vertical Ground Motion on the Seismic Performance of an Earth Dam

Earthquake-induced permanent displacements and distortions, as well soil mass movements and cracks, may significantly affect the post-seismic service- ability of earth dams. To minimize these effects the seismic design or retrofitting procedures should aim to improve the resilience in terms of ability to recover and adapt to the severe earthquakes. In this vein, through 2D numerical analyses, the paper investigates the role of the vertical component of the ground motion on the seismic performance of an earth dam. The results of the analyses are described in terms of main features of the seismic-induced plastic mechanisms and magnitude of the corresponding crest settlements showing that in some cases the effect of the vertical acceleration component is not negligible. Finally, an empirical correlation between some seismic parameters and the permanent crest settlements of the dam has been proposed.