METHOD OF ZONING OF REGIONAL SLOPE STABILITY BASED ON TYPICAL PROFILES ANALYSIS

The zoning of regional slope stability has very important significance for the landslide disaster prevention. In order to study regional slope stability, this study provides a regional slop stability zoning method in loess areas based on typical profiles. At first, the whole study area is divided into slope units using hydrology tool in ArcGIS.The raster data of the slope unit distribution and the DEM are imported into MATLAB.Secondly, the slope profiles in each unit are extracted along the average aspect calculated using least squares method. One profile represents one slope unit. Thirdly, MATLAB is used to formulate the command line files of FLAC^2D, including all the information of each profile, material parameters of soil, initial saturation, pore pressure conditions, constraint boundary and so on. Then all the command line files of FLAC^2D are executed automatically. The strength reduction method is induced to calculate the stability of each typical profile. Finally, the distribution of safety factor is mapped on the study area. In order to evaluate regional stability intuitively, we make the regional slope stability partitions for further assessment. We select Yaoxian as the study area and divide 946 typical profiles to calculate the stability of every slop unit. The study area is divided to three zones:unstable region, fundamental stable region and stable region. The zoning result is consistent with the actual survey. We can apply a single slope quantitative calculation to the whole region and combine the GIS analysis with external program calculation. This method improves the computation efficiency and accuracy effectively and can find potential sliding surface of the landslide. It is a new thought for prediction of regional slop stability in loess area.