Numerical Simulation Of Loess Landslide Deformation Process In Heifangtai Area

Lots of loss landslides have developed in Heifangtai of Gansu Province, which have seriously affected local people’s normal production, life and local socio-economy for the characteristics of high frequency and destructive, it has very important practical significance to research on the deformation process and its evolution regularity of the loess landslides, and making scientific prediction to the development of landslides in order to put forward corresponding measures according to actual situation in the area.According to the landslides disasters around the Heifangtai platform as the research object, based on the analysis of geological environment, through the actual investigation and mensuration of field and the statistical analysis, calculating and analyzing the acaul failure process of loess landslide in Heifangtai area by FLAC3D. Through the research and calculation, the main conclusions are as follows:Firstly, loess landslides and loess-bedrock landslides developde around the platform, which account for60%and40%respectively.Secondly, the Landslide edge cracks are characteristic of the landslides disasters in Heifangtai area, whether loess landslides or loess-bedrock landslides, and the overall statistical regularity of cracks also has a certain similarity contact with the distribution regularity of landslides in the area, fracture characteristic of the crack:the distance of the crack from edge*the extension length of crack, the width of crack, the depth of crack, and the overall distribution of crack, have a parabolic potential regularities of distribution generally. The "line styled cracks" which are parallel to the edge of landslides are dominated in loess-bedrock landslides, it has wide distribution range, often up to50meters away from the edge, while the edge cracks of Loess landslides are mainly concentrated in within30meters of the edge, and have criss-crossing distribution with the style of "Z" and "W", the regularity of development of edge cracks has a very close relationship with the concrete forms and conditions of landslides.Thirdly, though the modeling analysis of loess landslide by FLAG3D, researching its deformation and failure process, obtaining the curve of stress-strain, the shear strain deformation characteristics of failure region, the curves of speed, the displacement curve of the soil in the failure progess of landslide and so on. The result of the modeling analysis of loess landslide is largely in line with the actual situation. We have a conclusion that the loess landslides in the area of jiaojia are understabled combined with the development situation of the edge cracks of loess landslides.Finally, we put forward the corresponding prevention measures according to the development characteristics and inducing factors of loess landslides in Hefangtai area.