库岸复杂滑坡体形成机制的数值分析

Numerical analysis of formation mechanism of complex landslide on reservoir bank

三峡库区黄土坡滑坡已历经了几十年的勘察,但对其复杂滑体结构的成因机制仍有待研究。论文从分析黄土坡滑坡体I号崩滑体的原岩结构特征及岩体风化泥化过程入手,通过数值模拟研究了斜坡发育过程中滑坡的演化机制。模拟结果表明,斜坡表层拉应力的分布及深部夹层剪应力的集中有利于岩体的风化泥化。数值分析结果较好地解析了黄土坡滑坡复杂滑体结构的形成机制,指出前缘断层发育与斜坡岩体深部夹层泥化是其形成演化的关键因数。数值分析也表明三峡水库蓄水对滑坡整体稳定性的影响较大,模拟结果还表明,潜在滑带由深部泥化夹层控制。

Huangtupo landslide in Three Gorges Reservoir Area has been explored for several decades,but the formation mechanism of the complex landslide's structure has yet to be studied. Starting with the analysis of original rock structure and rock weathering process within Huangtupo landslide 1 # slumping mass,the landslide evolution mechanism was studied by numerical simulation in this paper. The simulation results show that the tensile stress distribution on slope surface and the shear stress concentration in deep interlayers are beneficial to rock mass' weathering and mudding. The formation mechanism of Huangtupo landslide's complex structures are explained by the numerical simulation results,the key evolution factors are the leading edge fault and the deep mudded weak interlayer within slope. Numerical analysis also shows the impoundment of the Three Gorges Reservoir has great influence on the stability of the landslide,the results also show the potential sliding zone is controlled by deep mudded interlayer.