Study On Stability Analysis And Prevention Engineering Of Loufangshan Landslide

Landslide is a kind of geologic disaster, which is extensively existed in our country. The Wudu-Guanzigou section of Lanzhou-Haikou Expressway is under complex geological conditions*which has great influence on the normal operation of the expressway. So it is very important to study stability analysis and prevention engineering of landslides in order to ensure the long-time stability of them.Based on Loufangshan landslide, the shear strength parameters of slip surface are back-analysised; the three-dimensional numerical model of Loufangshan landslide is established by FLAC3D; and its pre-reinforcements are simulated. The primary contents are as follows:1. The research achievements and related theory of landslides at home and abroad are summarized. Stratum lithology, topography and geomorphology, geological structure and hydrogeology conditions of landslide area are analyzed systematically and the mechanism of deformation and failure of landslide is discussed.2. Firstly, the shear strength parameters of slip surface are back-analysised, then quantitive evaluation of landslide is carried out, and the residual sliding force under different conditions are calculated, and abnormal operation mode two is selected as control condition.3. Numerical analysis principle of FLAC3D is described, and the three-dimensional numerical model is established. By analyzing distribution of displacement field, stress field, plastic zone, and combining with stress and strain status of the typical profile, the stability of landslide under natural condition is evaluated.4. According to the abnormal conditions two, high-pressure grouting and steel micro-piles groups are given. For a comparative analysis with steel micro-piles, common anti-slide piles with different sites, section size, anchoring depth and separation are simulated, and the optimum reinforcement of common anti-slide piles is given. Finally the results are compared between high-pressure grouting and steel micro-piles groups and common anti-slide piles. It is shown that the displacement of landslide is about the same, but the quantities of high-pressure grouting and steel micro-piles groups are small and economic.5. At last, the work and main achievements of full text are summarized, and recommendations for further research.