Identifying the Main Control Factors for Different Deformation Stages of Landslide

Water level fluctuations and rainfall, as external factors, are typically the two dominant causal factors of landslide deformation in the Three Gorges Reservoir Area. A quantitative model capable of evaluating landslide deformation processes is critical for early warning of landslide. The primary purpose of this paper is to take the Zhujiadian landslide as an example to determine the main control factors for different deformation stages of landslide. Original field date collected from the Zhujiadian landslide was examined using the grey relational grade analysis (GRGA). The approach consists of three steps: determination of landslide type, data processing, and identifying the main control factors of landslide deformation. The results obtained suggest that the Zhujiadian landslide is typical retrogressive landslide, and its deformation occurred first at the front part of the landslide and progressed upslope due to drawdown of reservoir water level and heavy rainfall. In the whole deformation process, the main control factors of different parts of landslide changed with the landslide development. Thus, the findings of the study are useful for rapidly predicting landslide deformation relating to water level fluctuations and rainfall, and the GRGA is useful for interpreting the main control factors of landslide deformation from a quantitative point of view.