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Vegetation is natural and environment-friendly material for slope reinforcement. To simple and effective analysis of vegetated slopes, a new method is proposed to consider the tensile strength cutting criterion (C-F criterion) of unsaturated root-soil composites. The proposed method incorporates the hydrological and mechanical effects of vegetation roots. A 1D stability model is developed to calculate the safety factors of vegetated slopes under steady transpiration state. Parametric studies are performed to investigate the effects of shrub root depth, slope angle, rainfall intensity, transpiration rate, and tensile strength on pore-water pressure (uw) and slope safety factors (Fs). uw and Fs are calculated using both the C-F criterion and the Fredlund strength criterion. The results demonstrate that Fs and uw decreases with increasing slope angle and rainfall intensity. Slope angle and rainfall intensity of vegetated slopes has a negative impacts on the slope stability. Moreover, Fs increases with increasing tensile strength. Furthermore, the transpiration rate and root depth increases, Fs and uw increases. Root depth, tensile strength, and transpiration rate are adverse for slope stability. Increasing slope angle and rainfall have detrimental effects on slope stability. Shallow slopes are more sensitive to rainfall than deep slopes. Fs for vegetated slopes with tensile strength cut-off are reduced compared to those based on the Fredlund strength equation. The C-F criterion is best suited for evaluating the shallow slope stability. Overall, the proposed method is a simple and practical approach to assess the vegetated slopes stability.

来源平台：ENVIRONMENTAL EARTH SCIENCES