Buckling strength of thin-shell concrete arch dams: Fid-Bau Portal

Buckling strength of thin-shell concrete arch dams

Zingoni, A. / Mudenda, K. / French, V. / Mokhothu, B.

Abstract An investigation has been undertaken on the buckling strength of concrete arch dams in the form of thin shells of single and double curvature. When subjected to the hydrostatic pressure exerted by the retained water, the shell experiences predominantly compressive internal actions, which can result in buckling failure of the thin shell. There are many factors influencing the buckling strength of the arch dam. These include the shape of the valley, the geometry of the arch surface, the degree of bulging of the arch, shell-thickness variation and support conditions. The present study makes use of FEM modelling to determine the influence of key parameters on the critical buckling pressure of cylindrical and elliptic-paraboloidal arch dams. For cylindrical arch dams, design curves giving information on factors of safety against buckling are presented. By comparing the results for the elliptic paraboloid with those for the parabolic cylindrical arch, the benefits of double curvature are evaluated.

Highlights ► Presents a strategy for the systematic study of the mechanics of concrete arch dams. ► Presents a framework for the systematic compilation of design guidelines for arch dams. ► Derives parametric design curves for factors of safety against buckling for cylindrical-profile arch dams. ► Quantifies the beneficial effect of double curvature in enhancing buckling resistance of curved thin-shell concrete arch dams.