在研究各种动力人工边界的基础上根据地震波的不同传播特性 ,针对土石坝地基系统 ,提出 :对地基的底边界和侧边界分别施加粘性边界和叠加边界 ,以消除或减小常规刚性边界上波的反射对动力分析成果的影响 ,使土石坝动力分析成果更为可靠合理 .在应用叠加边界时 ,通过引入常速度初值的更新而将波的传播限制在较小的边界区域内 ,使得结构系统的主区域仍能应用非线性有限元方法 .这样的处理使得叠加边界方法能够应用于非线性问题的边界区域 ,又大大减小了计算工作量 . Based on the study of different dynamic artificial boundaries and according to the different propagation characteristics of seismic waves, this paper proposes a method of applying viscous boundary and superposition boundary respectively to the bottom boundary and side boundary of foundation to eliminate or reduce the conventional rigid boundary The influence of wave reflection on the dynamic analysis results makes the dynamic analysis of earth-rock dam more reliable and reasonable.When the superimposed boundary is applied, the wave propagation is limited to a smaller boundary area by introducing the update of the initial value of the constant velocity, The main area of ​​the structural system can still use the nonlinear finite element method, which makes the superposition boundary method can be applied to the boundary area of ​​nonlinear problems and greatly reduces the computational workload.