Numerical analysis of earthquake response of an ultra-high earth-rockfill dam

Abstract. Failure of high earth dams under earthquake may cause disastrous economic damage and loss of lives. It is necessary to conduct seismic safety assessment, and numerical analysis is an effective way. Solid-fluid interaction has a significant influence on the dynamic responses of geotechnical materials, which should be considered in the seismic analysis of earth dams. The initial stress field needed for dynamic computation is often obtained from postulation, without considering the effects of early construction and reservoir impounding. In this study, coupled static analyses are conducted to simulate the construction and impounding of an ultra-high earth rockfill dam in China. Then based on the initial static stress field, dynamic response of the dam is studied with fully coupled nonlinear method. Results show that excess pore water pressure accumulates gradually with earthquake and the maximum value occurs at the bottom of core. Acceleration amplification reaches the maximum at the crest as a result of whiplash effect. Horizontal and vertical permanent displacements both reach the maximum values at the dam crest.