NEHRP Clearinghouse

Title
Dynamic Response of Embankment, Concrete-Gravity and Arch Dams Including Hydrodynamic Interaction.
File
PB81152324.pdf
Author(s)
Hall, J. F.; Chopra, A. K.
Source
National Science Foundation, Washington, DC., October 1980, 242 p.
Identifying Number(s)
UCB/EERC-80/39
Abstract
An analysis procedure in the frequency domain is developed for determining the earthquake response of a dam including hydrodynamic interaction and water compressibility effects. Linear responses of idealized, two-dimensional gravity dams and three-dimensional dams, including arch dams, can be obtained. The dam and fluid domain are treated as substructures and modeled with finite elements. The only geometric restriction is that an infinite fluid domain must maintain a uniform cross-section beyond some point in the upstream direction. For such an infinite uniform region, a finite element discretization within the cross-section combined with a continuum representation in the infinite direction provides for a proper transmission of pressure waves. The fluid domain model approximately accounts for fluid-foundation interaction through a damping boundary condition applied along the reservoir floor and sides. The dam foundation is assumed rigid. Hydrodynamic effects are shown to be equivalent to an added mass and added load in the frequency domain equations of motion of the dam. Hydrodynamic effects on the dam response are investigated for acceleration responses to harmonic ground motions. Complex frequency response functions for acceleration at the dam crest are presented for two-dimensional concrete gravity and earth dams and for a three-dimensional arch dam. Several reservoir shapes are included for the concrete gravity dams. Water compressibility and fluid-foundation interaction significantly influence the response of concrete gravity dams and are even more important for the arch dam. One effect is a greatly increased importance for the vertical component of ground motion. Hydrodynamic effects on the responses of earth dams are shown to be minor.
Keywords
Mathematical models; Arch dams; Gravity dams; Dynamic response; Earthquake engineering; Finite element analysis; Foundations; Hydrodynamics; Concrete dams; Earthquakes; Boundary value problems