The deformed rock mass at the right abutment of the Heihe Reservoir of Xian City was formed by rotation.Thus, the analysis of its stability must be performed by three-dimension method.

• 西安市黑河水库右坝肩变形体是在旋转变形条件下形成的,这样,对它的稳定性评价必须按空间问题来考虑,要用三维分析方法来计算它的稳定性。