Influence of plant root reinforcement on 3D geosynthetic slopes

Abstract

Plant roots serve as a natural reinforcement method with the potential to significantly enhance slope stability. In engineering practice, roots can function synergistically with geosynthetics, reducing the reliance on artificial materials. Based on a three-dimensional (3D) rotational failure mechanism, this study proposes a novel framework to evaluate the influence of plant roots on the stability of geosynthetic-reinforced slopes. By integrating the hydrological effects of transpiration and the mechanical composite action of root – soil interaction, the reinforcing capacity of uniform root systems is comprehensively assessed. The required dimensionless reinforcement strength at the limit failure state is derived using the functional balance equation. The validity of the proposed method is confirmed through comparisons with existing two-dimensional (2D) solutions for vegetated slopes and 3D solutions for non-vegetated reinforced slopes. Furthermore, various parameter plots are provided to facilitate design analysis. The results indicate that accounting for 3D spatial effects and plant root reinforcement significantly reduces the required reinforcement strength, thereby lowering construction costs and enhancing overall slope safety.

Keywords

slope stability / plant roots / geosynthetics / 3D reinforced slopes / limit analysis

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Central South University