Research On Application Of The Inclined Drainage Hole To Landslide Treatment And Analysis Of The Influence Factors

Along with the development of China’s socialist construction, in a variety of projects, such as highway engineering, railway engineering, mining engineering and hydropower station projects often need to dangerous landslide treatment, the landslide treatment’s degree is usually determines the progress and economic costs of a project. Therefore, through systematic deep research of causes of landslides,formation mechanism,seepage field and landslide stability in the conditions of drainage,grasp the main factors,the formation laws,such works will provide a very good experience in the future construction of projects.This article’s main research contents and conclusions are as follows:①Based on some understanding of the multi factor sensitivity analysis theory and methods that based on the orthogonal analysis method.In the light of the main factors of landslide, this article lists the main five factors: soil severe, cohesion, internal friction angle, pore pressure ratio, water level. Using the multi factor orthogonal test method for sensitivity analysis to find out that the change of landslide stability on the internal friction angle is the most sensitive;followed by the cohesion, head height, pore pressure ratio; the density of the soil is most sensitive to changes.② Analysised the mechanism of landslide stability influence of groundwater, expounds the basic theory of saturated unsaturated seepage. Established the calculation model of seepage and stability analysis of landslide, selected the characteristic parameters of landslide soil, seepage calculation parameters and boundary conditions.Systematically analyzed the seepage field and stability changes in different length, aperture and elevation of the inclined drainage holes. Coming to conclusion: layout of drainage holes to drainage effect on landslide, enhance the overall stability of the landslide; the longer the inclined drainage hole is,the better the effect are and the region are more extensive,but also combined with the required of the landslide treatment water level and the actual geological condition; the drainage effect of inclined drainage hole of elevation less sensitive,it needs according to the actual position of the free surface to determine, the recommended value of elevation angle at 6° to 10° in more reasonable range; the drainage effect of inclined drainage hole’s aperture is most sensitive to changes, recommended aperture D is about 0.1m more appropriate.③ Overview of domestic and foreign about the inclined drainage hole of the development process and the status quo. Mainly introduces the foreign regulations about the inclined drainage hole related construction machinery and construction technology, and put forward some effective suggestions for optimization.Such as the front part of inclined drainage holes are arranged into 50% upper permeable, impermeable bottom 50%; arranged the PVC or PE infiltration pipe that is slightly smaller than the drainage hole in the inclined drainage hole; orifice grouting and sunscreen treatment, near the outlet 60 cm within the length of the gap between the plug drilling and drainage pipe with clay or sealing material, the slope under the orifice of inclined drainage hole should do strengthening treatment, to prevent erosion of slope; on a regular basis to clean up the drainage hole, to prevent the blockage of drainage holes and so on.