Nonlinear Finite Element Seismic Analysis of The Shuiniujia Rock fill Dam

摘要

The Shuiniujia dam locates at the Huoxi River in Sichuan province in China. It is a rockfill dam with an earth core, the maximum height of which is 108m and the thickness of overburden layer is 28.05m. The basic seismic intensity at the location is eight degrees. It is a zone with high seismic intensity, so the safety of dam during earthquakes is of great importance. Three dimensional dynamic finite element analysis is employed to study the dynamic behaviour of the dam during earthquakes. The initial stress fields of the soil elements are computed by static calculation, in which the nonlinear elastic Duncan-Chang constitutive model has been adopted to simulate soil behavior. In dynamic calculation, the soil is considered to be viscoelastic material and the equivalent linearization dynamic constitutive model is also applied for simulation. The viscous-elastic boundary is set along the model boundaries. The peak absolute acceleration responses are analyzed. The dynamic shear stress and permanent deformation are computed. In addition the safety factor of stability of the dam slope is studied. Finally the sensibility of the material dynamic parameter of rockfill and earth core is analyzed. According to the analyses abovementioned, the safety of dam during earthquakes is evaluated.