On the Application of Mechanical Reinforcement of Tree Roots to Slope Stabilization

Abstract

The root strengthening effects on soil behind retaining walls may be quantified by a simplified equation ΔS = 1.2TR(AR/A) where ΔS, TR and AR/A are the shear strength increase, tensile strength of root and root area ratio respectively. However, this effect is ignored during stability analysis due to the possible significant variability of the potential beneficial effect and extreme difficulty in fully characterizing the tree roots and quantifying their effects. In this paper, advancements in the last few decades in biotechnical slope stability are reviewed. Representative models to quantify the mechanical effects of tree roots are studied. If other potential beneficial effects due to existence of roots and suction effect due to transpiration of tree are ignored, the term 1.2, root tensile strength and root area ratio may still be the three key parameters to the root strengthening effect in slope stability.