a special boundary condition should be used in the dynamic analysis of rockfill dam with the finite element method. A series of dynamic analyses are performed in time domain by using viscous and rigid boundary respectively and compared with dynamic analysis results in frequency domain. The results show that
with the increase of the height of rockfill dam
the influence of viscous boundary become increasingly obvious. The acceleration of dam top calculated with viscous boundary is lower 10% ~20% than that with rigid boundary for homogeneous dam. For the Shuangjiangkou Clay Core Rockfill Dam
the acceleration of dam top calculated with viscous boundary is lower 30 % than that with rigid boundary.