Analysis of arch dams

A theory for arch dams based on extended shell theory is given and compared with finite-element-shell and three-dimensional (3D) analyses. The dam equations given are solved by successive overrelaxation. In a flexible valley, stress boundary conditions are used. Various loading cases and the pore-water-pressure effect are discussed. Valley-flexibility effects are realized effectively by means of Vogt's equations and a normal shear valley-deformation analysis given by the writer. On basic theory it is found that in spite of some intrinsic differences there is good agreement between the results of this classical theory and those of the finite-element analyses, which are very similar. It is concluded that for any arch dam a rigorous shell analysis is as good as a sound 3D analysis: and that the second approximation is as good as the full theory. Also, it is found that the boundary extension artifice depresses transverse displacements.