Permeability and strength characteristic of surface soil containing roots

This paper describes permeability and shear strength characteristics of a surface soil containing tree roots. In this study, Tsukushihagi and Twine were used as tree roots and its alternatives, respectively. Tensile strength of tree roots was measured using a newly developed tension test apparatus. Also, falling head permeability and direct box shear tests were performed on specimen prepared with soil samples mixed with the tree roots or the alternatives. Main conclusions are as follows. 1) The tensile strength increased with an increase in diameter of tree roots. 2) The coefficient of permeability seems to be not changed by mass content of tree roots. 3) Whereas the internal fiction angle of soil containing tree roots is almost constant, the apparent cohesion increased with increasing the mass content of tree roots.

tree roots

box shear test

vegetation

permeability

tensile strength