在土质边坡稳定性分析中，滑裂面的确定至关重要，而当前普遍采用的圆弧滑动面法会产生较大误差。采用滑移线场理论确定滑裂面，并结合动力有限单元法，提出了一种地震作用下土质边坡稳定性的分析方法。首先求出地震作用下土坡的应力场，运用滑移线场法搜索得到不同时刻土坡的临界滑移线，然后再根据临界滑移线上的应力分布求出对应于该滑移线的安全系数，以最小平均安全系数作为评价指标，实现地震作用下土质边坡的稳定性分析，最后结合工程实例，求得不同时刻的土坡临界滑移线及其对应的安全系数，并对该土坡的动力抗震稳定性进行了评价。分析表明：安全系数小于1.2的滑移线共同构成了地震作用下土坡的剪切带，与土坡的塑性区吻合，验证了文中分析方法的合理性。

It is important to locate the slip surface in stability analysis of soil slope. The current method, circular slip surface method, results in a major error in the simulation analysis. In this paper, a method for seismic stability analysis of soil slope is proposed based on the theory of slip line field and dynamic finite element. Firstly, the stress field of soil slope is determined under seismic loading. Then, the method of slip line field is used to search the critical slip line under different conditions, and safety factor for every slip line is achieved. Finally, the seismic stability analysis of soil slope is quantified by the minimum mean safety factor. The proposed procedure is used to determine the critical slip lines and safety factors of an example slope at different moments. Seismic stability of the soil slope is evaluated by using the minimum mean safety factor. The study indicates that the shear band is composed of the slip lines with safety factors below 1.2. The shear band is consistent with the plastic zone of soil slope.