The results show that distinct " bench " distribution rule takes on for the subsidence and distortion of bench - shape slope surface ; the movement range of bench - shape slope surface is smaller but its distortion is larger than those of flat surface and concentrated distortion occurs at every bench plan ; the surface horizontal distortion of bench - shape slope is still pressed in gob centre and tensioned in both sides of gob ; space - time effect should be taken into account for the stability of bench - shape slope influenced by underground mining 结果表明:露天煤矿台阶状边坡体的采动沉陷规律表现出很明显的“台阶”分布特点;台阶状边坡地表的移动范围比平地地表要小,但变形却更剧烈,且在各台阶平面处形成变形集中;台阶状边坡地表的水平变形仍然呈现出采空区中间受压,两端受拉的特点;台阶状边坡在地下开采扰动下的稳定性应考虑采空区的时空效应。