Earthquake Hydrodynamic Pressure on Dams

Abstract

Hydrodynamic pressures on the vertical upstream face of straight dams during horizontal earthquakes were studied by Westergaad in 1933, and an analytical solution was obtained. Assuming that water is incompressible, an approximation can be made to reduce Westergaad’s mathematical formulation to the Laplace equation. The computer program SEEP2D, from the U.S. Army Corps of Engineers (COE), is available for the study of seepage flow in porous media; this flow can be expressed mathematically in a form of the Laplace equation. Therefore, we can use this computer program to study the hydrodynamic pressure on dams during a horizontal earthquake in the upstream/downstream direction. In practice, the proposed procedure is not limited to SEEP2D but can also be applied to any computer model capable of solving Laplace equations in bounded domains. Two examples are presented to show the application of the COE’s computer program, and the accuracy of the proposed method is discussed.