Limit Load of Soil-Root Composites

This paper studies the influence of root reinforcement on shallow soil protection by using Finite Element (FE) method. Taking the root-soil composite as a periodic material, the homogenization method is used to construct a Representative Volume Element (RVE) that consists of roots and soil. This RVE is discretized by a two-dimensional (2-D) FE mesh, while special formulation is established so that this model is capable of describing three-dimensional (3-D) deformations when the strain is invariant along the fiber axis. The important effect of debonding on the interface between the fiber and the matrix is also considered by using a special interface element. To verify the validity of the proposed computational model, tri-axial tests were conducted, where the root-soil composite was subjected to axial and lateral pressures. Good agreement of limit loads has been achieved between the numerical and the experimental results.