Gis-Based Stability Analyses Of Loess Slopes

The landforms of China's loess area are very unique with special geotechnical properties.Landslide in this loess area is characterized by high frequency and huge damage.Consequently,landsliding has resulted in severe economic loss and casualties,and caused tremendous inconveniences to production activity and people's life.Taking the loess slope of south Jingyang platform in Shanxi province as an example for this paper,field survey were conducted,and the 3D geological model of south Jingyang platform was built using relevant data on contour maps and boreholes.At the same time,development of GIS was realized using C# in Visual Studio 2010 to create the stability analysis system for loess slope.With adopting the Sweden slice method to calculate the safety factor of slope,introducing the scanning algorithm of landslide profile line into the stability analysis system for loess slope,a set of safety factors are utilized to represent the stability status between the whole slope and its parts.This paper focuses on the following four aspects:1.Field survey and data collection: the field survey presents me a better and deeper knowledge and understanding of the distribution of landslide in the study area.Meanwhile,drilling samples in typical landslide area and relevant data collection are conducted so as to provide basic data for the construction of landslide model and the stability analysis.2.Building 3D geological model of loess slope.Topographical maps were adopted to build the digital elevation model(DEM)of loess slope in GIS.Borehole data and DEM were then combined to develop 3D geological model of the loess slopes.3.Conducting the 3D stability analyses of loess slopes.Plug-in development was realized on the basis of GIS component.According to the algorithm of profile line,the circular slip plane was created on the profile line.And the calculation of safety coefficient was conducted with the DEM data on the targeted area and the Sweden slice method;4.Using the scanning algorithm of slope profile.The possible area of landslide was scanned using parallel profile line based on the DEM data so as to achieve the calculation of the factor of safety of multiple 2D profiles.