Abstract
The discussion, in this paper, is confined to the natural vibration of the fill dam which can be described by the truncated wedge of inhomogeneous rigidity: G=Gm·(z/h)n where G: modulus of rigidity, z: distance from the top of dam, h: dam height, n: rigidity index, and with rectangular canyon shape. Equilibrium of the bending moment and the shearing force in the vertical direction, together with the shearing force and twisting moment in the transverse direction, leads to the fundamental dynamic equations of the prescribed model of dam.
Finite difference method is used to determine the natural frequencies and natural modes of the dam. The frequencies and the modes are computed for the various rigidity index n, the canyon width and the bottom width, the results are put in order in graphical or tabular forms.
