Study On Development Characteristcis And Perniciouness Of Gaoqiao Gully Debris Flow In Hanqing Section Of Mianmao Highway From Sichuan

Gaoqiao gully is located in Tianchi village,northwestern Mianzhu city,Sichuan Province, which obliquely crosses Mian Yuan River at its endpoint. This area suffers masses of loose solid material brought by the "5.12" earthquake and also heavy rainfall in the rainy season of2010and2011. In this situation, two large-scale debris flows occurred in Gaoqiao gully. Its happening severely threatenes the human life and property which located in Gaoqiao gully or along the line of HanQing section. To avoid the perniciousness to HanQing section of MianMao highway, factories and mines around and post-disaster reconstruction which future debris flow in Gaoqiao gully may cause, The study of debris flow in Gaoqiao gully and its prevention have become extremely urgent.In view of engineering geology, this article has researched on geographic and geomorphic conditions, stratum and lithologic character, geologic structure, weather and hydrogeological conditions, human engineering activities around Gaoqiao gully, and anylsed conditions of topography, loose solid material and water on what may lead to debris flows in Gaoqiao gully. After all this research, this article summarized its development characteristics, genetic mechanism and activity characteristics. According to its development characteristics, this article summarises the debris flow in Gaoqiao gully as a kind of viscous, high-frequency, rainstorm, gully, toppling and gully bed eroded, hydraulic, large scale type debris flow. Based on characteristics of debris flow itself, this article choose the newest research results to calculate the dynamic characteristic and motion features of debris flow in Gaoqiao gully. On this basis this article makes predictions of the development trend and analyze perniciousness of debris flow in Gaoqiao gully, then makes following suggestions for its prevetion engineering. Stress should be put on the shelter for prevetion engineering of it. Gaoqiao gully itself is better to be made to a huge channel to stop sludge. Use controlling for material supply by prevention project to achieve the goal of reducing fluid weight, sediment correction coefficient and the channel blockage coefficient. Through this change, discharge of debris flow can be reduced significantly to the extent that it has no ability to cause mass hazards. Evently, blocking or accretion of Mian Yuan River can be avoided which means achive the target of protecting nearby factories and guarantee safty for reconstruction.