三峡库区平缓层状软硬相间斜坡变形模式变化分析

三峡库区发育大量软硬相间斜坡岩体，其变形机制复杂多变。以涪陵岩上危岩体为例，分析塑流-拉裂型斜坡的变形控制因素为厚层软基；以云阳云江路高边坡为例，分析压致-拉裂型斜坡的变形控制因素为薄夹层。采用应力分析的方法，对两种类型的岩体破坏进行了分析。塑流-拉裂型斜坡岩体以岩石的拉张破坏为主；滑移-压致拉裂型斜坡岩体以岩石的压张破坏为主。两种模式在结构上的差别为软岩厚度的差别。以巫山望霞危岩体为例说明，当软岩厚度处于相间位置时，其变形模式为复合模式。因此斜坡内部的岩体结构类型与斜坡变形破坏地质力学模式有着密切关系，斜坡结构变化则变形模式相应变化，其模式可能为过渡的复合式。这一认识对判断单个平缓软硬相间斜坡的变形问题具有积极的指导意义。

ANALYSISING ON DEFORMING MODE TRANSFORMING OF GENTLE SOFT-ARD INTERBED SLOPES IN THREE GORGES RESERVOIR

There is many soft--hard interbed slopes in Three Gorge Reservoir and their deformation is complex. The factor causing the plastic flowing--cracking slope deforming is thicker soft rock basis, such as Fuling Yanshang Dangerous rockmass. The factor causing creeping compressing--cracking slope deforming is weak seam, such as Yunyang Yunjiang cutting slope for example. By stress analysising, these tow type modes of rockmass failure were analysed, the former is rock extense cracking, the later is compressing crack. The difference between the two modes is soft rock thickness in structure. When the soft seam is thick in some value between two threshold, the mode is compositing mode, and the slope deformation mechanism is closely re lated to rockmass structure. The structure varied, and the deforming mode varied so that the mode may be a transitional compositing mode. These results could help understanding of the single gentle bedding soft--hard interbed slope deforming.