摘要
廖家坪危岩体位于三峡库区长江左岸,危岩体内部发育有7层软弱岩层和2组裂隙,其变形机制为次生倾倒。采用UDEC离散元模型,对该危岩体倾倒机制进行了数值模拟。模拟结果表明,廖家坪坡体内因次生倾倒形成的拉裂破坏向坡内呈递减趋势;坡体内的倾倒块体受软弱层控制,一般不穿越软弱层,因此不会发生整体性倾倒破坏。各次级悬崖上的危岩体岩柱形成后,出现了向前倾倒翻转破坏和向后仰剧冲或蠕滑两种破坏方式。倾倒的方向与下伏软弱层破坏的关系密切,危岩体跟趾部破坏强烈则向前倾倒翻转破坏,趾部破坏强烈则向后仰剧冲或蠕滑。
Liaojiaping dangerous rockmass is located on the left bank of the Changjiang River, with fractures developed, it threats the local residents and Changjiang sea-route badly. There are seven soft layers and two groups of fractures in the roekmass, the deformation mechanism is the ＂secondary toppling＂ mode. Using UDEC model, the paper make numerical analysis on the toppling mechanism of the roekmass. The simulation results show that the crack failure by secondary toppling is reduced from the face to the back. Toppling block is controlled by the soft layer, as a whole, the block doesn＇t cross the soft layers, so it is impossible to topple as ane-piece. When dangerous roekmass or rock piles are formed in secondary cliffs, there are two failure type toppling to the front and toppling to the back. The toppling direction is related with belowed soft layer＇s failure seriously, when the toes of soft layer failure seriously the roekmass topples to the front, or the heel of soft layer failure seriously the roekmass topples to the back. The results of numerical analysis offer scientific idea for controlling of deforming rockmass, also it has important instruction to other dangerous roekrnasses study in the Three Gorges Reservoir Region.
出处
《水文地质工程地质》
CAS
CSCD
北大核心
2008年第5期24-27,32,共5页
Hydrogeology & Engineering Geology
基金
中国地质调查局灾害预警项目(1212010640601)
关键词
廖家坪危岩体
UDEC模型
次生倾倒
倾倒方向
Liaojiaping dangerous rockmass
UDEC model
secondary toppling mode
toppling direction
