湖北省巴东新城白土坡斜坡岩体稳定性分析

Analysis of rockmass' stability at Baitupo slope in Badong new town,Hubei Province

巴东组第三段是三峡库区滑坡发育的主要地层之一,巴东新城深部变形监测钻孔岩芯分析表明在巴东组第三段地层中发育有多层软弱夹层,以泥质灰岩、钙质泥岩为主,大部分破碎带具有顺层、连续等特点。白土坡斜坡岩体中主要贯通性夹层有13层,中上部夹层分布较密,西壤坡斜坡岩体中主要贯通性夹层有3层,与白土坡巴东组第三段下部夹层对应,巴东组第三段中的软弱夹层是斜坡深层岩体的主要结构面。白土坡深层岩体稳定性分析结果表明随着库水位的上升斜坡稳定性有下降趋势,但其整体稳定性较好,白土坡前缘断层为斜坡深层变形提供了边界条件。

The 3rd section of Badong Formation is one of the major strata where landslides developed in Three Gorges reservoir,the rock of T2b3 is mainly consisted of limestone and the weak intercalated layers in T2b3 composed of argillaceous limestone and calcareous mudstone.The cores of monitoring drills were compared,the result showed several fractured weak zones developed in T2b3 and these zones is consequent and continuous.the major thirteen penetrative weak intercalated layers of the 3rd section of Badong Formation at Baitupo slope developed,and most were located at middle and top part,the three penetrative weak intercalated layers corresponding to the lower part of T2b3at Baitupo slope developed at Xirangpo slope.It was concluded that the weak intercalated layers are the major structural planes of deep-seated rock mass at slopes.The analysis of stability of Baitupo deep rock show that the stability decreased gradually with the increase of reservoir’s water level,but Baitupo slope was still in integral stable status,the F3 fault on the leading edge of Baitupo provided the boundary condition for slope’s deep deformation.