以西安市某均质土坝为例，在上下游地层竖向边界不设置边界条件、加透水边界、加无限边界和无限边界加透水边界等条件下，计算了大坝和坝基渗流场，并进而采用Seep和Slope耦合，研究了边界条件的选取对渗流及边坡稳定的影响，得出如下结论：竖向边界简单取为无限边界时计算结果与实际不符；加透水边界时计算的渗流量和下游坡脚处的水力坡降符合实测资料，安全系数大小也比较可信。该结论可为边界条件的选取提供参考。

The coupled seepage and safety factors are calculated in some homogeneous dam in Xi ' an City under the following four boundary conditions, i.e. not setting vertical boundaries, setting a permeable boundary, adding an infinite boundary and instituting both infinite and permeable condition. The slope stability is analyzed with slope calculation considering seepage. The calculated result shows that it is not coincident with the measured data under the infinite boundary condition, while that it is in accordance with the measured data under permeable boundary condition. The conclusion could provide a reference in setting the boundary condition.