Land Use Reseach Of Gully Type Landslide In The Loess Plateau

China is the world's most widely distributed areas of loess, and Loess Plateau is the main part of the loess. As the Loess Plateau is located in the second step of topography in China, and the loose loess structure, lead to serious soil erosion, broken terrain and ravines aspect. Valley incision,lateral erosion and human engineering activities trigger further landslides in loess, and generate the formation of a typical valley landslide, that type of loess landslide valley. The occurrence of valley-type loess landslide, on the one hand it may destroy the personnel, property and the living environment, and form geological hazards;on the other hand it will make the original topographic slope slow down, provide more suitable living environment for human,form the geological features of resources. As a geological disaster, domestic and international research is very extensive and in-depth, However, as geological features of resources, less research in this area, especially the type of research literature for loess landslide valley land-use is very few.This paper presents the Loess Plateau gully type based on the Landslide, and analyze of the development of valley landslide features and formation mechanism, and while looking back the conventional landslide measures and the results of previous land use of landslide, summarizes the key technical issues of valley type of land use aspects of loess landslide of the Loess Plateau. We think the classic technical methods such as "cutting head, waist, presser foot" are not suitable to the remediation of the valley-type loess landslide. It is not only ineffective governance, and economic costs are also too high. Against the unstable failure of valley-type loess landslide once more due to the continuously eroding of the flow to the landslide, which is the feature of the free face produced by the landslide front, Propose the measures based on the "side of the block+drainage",to prevent the flow from continuously eroding the landslide, thus to renovate the landslide, and to reach the technical ways of land use. The measure of"side of the block" is to establish a retaining wall in the valley downstream direction along the landslide sidewall.There are two purposes:The first is to raise datum plane of erosion, avoiding the flow coming from the upper valley continuously eroding the landslide, and the design height of the retaining wall depends on the safety factor of the landslide, that is to ensure the minimum free face height of the landslide front of the safety factor; the second is to make the landslide sideslip down along the valley direction, and the design width of the retaining wall depends on the size of the landslide sideslip force, and that is to support the landslide not to sideslip down along the valley direction. "Drainage" measures, including surface drainage system and underground drainage system. Surface water drainage system adopts open channel guide, and the design section size and slope depends on the upper valley water, that is, to make the valley upstream inflow pass through the body from a landslide along the open channel, not to erode the landslide. Underground drainage system uses filter pipe, gravel filter material, geotextiles, blind channel material to drainage the groundwater in the landslide body,Its ability to design drainage water depends on runoff of the underwater in the landslide body, which can effectively discharge the groundwater in the landslide body in order to prevent the water table rising and causing the landslide.Using this technical methods to design Yanjiagou landslide in the Zichang County of Yan'an City,it can realize the lower Cost of Gully type landslide in the effective and comprehendsive utilization of land.