Slope Stability Analysis And Support Design Application Besed On Point Safety Factor Method

The safety analysis of slope engineering is a hot researching spot of the geotechnical engineering field at home and abroad. In this paper, point safety factor method based on displacement iso-surface is the theoretical basis. By means of three-dimensional finite difference software FLAC3d and Tecplot data visualization software to analyze slope stability, to calculate point safety factor and the overall safety of slope different displacement iso-surface. Overall safety factor for the benchmark, displacement iso-surface corresponding minimum safety factor for the overall slope is potential sliding surface, and analyzes sliding mechanism of the Slope. To identify the relationship between point safety and sliding mechanism on the potential sliding surface.In this paper, this theory will apply to the highway landslide project which is at Danba 500kV substation and near Huang Tukan. We select typical profiles to analyze slope stability, and set up three-dimensional analysis model. Through on-site investigation and laboratory experiments, we determine the calculation parameters of the model, and analyze three-dimensional model of the slope typical profile stability.The main results obtained are as follow:(1) Strong deformation zoneⅠarea: overall safety factor is minimum on the 39mm displacement iso-surface, it is 1.0866. This displacement iso-surface is potential sliding surface of the slope. Strong deformation zone Ⅰ area is promote sliding mechanism.(2) Weak deformation zone Ⅱ-1 area:overall safety factor is minimum on the 39mm displacement iso-surface, it is 1.1269. This displacement iso-surface is potential sliding surface of the slope. Weak deformation zone Ⅱ-1 area is promote sliding mechanism.(3) Weak deformation zone Ⅱ-2 area: overall safety factor is minimum on the 15mm displacement iso-surface, it is 1.1081. This displacement iso-surface is potential sliding surface of the slope. Weak deformation zone Ⅱ-2 area is promote sliding mechanism.Simplified Bishop method of limiting equilibrium theory is used to analyze typical profiles of slope stability, calculate its safety factor. The results were 1.022,1.055,1.076。According to the calculation results of point safety factor method and limiting equilibrium method, the author analyzes the slope stability. On the basis of slope stability and each deformation zone’s sliding mechanism, we determine the initial position of anti-slide pile. According to the geological prospecting data and terrain conditions, we determine the final position of anti-slide pile and check anti-slide pile design.