GIS deterministic model-based 3D large-scale artificial slope stability analysis along a highway using a new slope unit division method

The high frequency of landslide hazards has caused great human casualties and economic losses in recent years around the world. Among the current available approaches to assess landslide hazard, deterministic approach provides the best quantitative information on landslide hazard which can be used directly in the design of engineering works. However, the approach is difficult to be applied to estimate the slope stability in large scale due to two problems: (1) detailed datasets about the spatial variation of input parameters of the hydrological and slope stability models cannot be acquired easily; (2) an efficient method to divide large-scale area into small mapping units that can be used as study objects for deterministic approach is required. To solve these two problems, all the spatial data involving the physical properties of a slope are modelled in 2D planar or 3D perspective, utilizing the strong spatial data modelling and interpolation capabilities of geographic information system. In addition, a new slope unit division method is also proposed to divide an artificial slope into many small slope units as the study objects for deterministic model. The objective of this study was to propose a set of procedure to evaluate the artificial slope stability along a highway. A 3D limit equilibrium model is used to calculate stability of each slope unit in the form of safety factor. After the safety factors of all slope units are calculated, the stability of the whole area can be assessed.