Numerical Earthquake Response Analysis of the Earth Dams

Numerical investigations are carried out to consider the seismic behavior of earth dams. A fully nonlinear dynamic finite difference analysis incorporating an elastic perfectly plastic constitutive model is taken into account to describe the stress-strain response of the soil during earthquakes. In addition, Rayleigh damping is used to increase the level of hysteretic damping in numerical analyses. The Masing rules are implemented into the constitutive relations to precisely explain the nonlinear response of soil under general cyclic loading. As a result, the soil shear stiffness and hysteretic damping can change with loading history. The constructed numerical model is comprehensive calibrated via the centrifuge test data as well as the field measurements of a real case history both in the time and frequency domains. Good agreements are shown between the computed and measured quantities. It is confirmed that the proposed numerical model can predict the essential fundamental aspects of nonlinear behavior of earth dams during earthquakes. Then, a parametric study is conducted to identify the effects of dam height and input motion characteristics on the seismic response of earth dams. To this end, three real earthquake records with different intensities and PGAs are used as the input motions.