Figure 4

Results of root penetration numerical analysis using the contact finite element method. (a) Root displacement, soil principal stress and soil displacement of the simulations for two β-values by changing soil strength E (kPa). The units of color codes are cm (left), MPa (middle), and cm (right). From the initial displacement (left), the resulting stress and displacement after deformation were calculated (right). (b) Schematic illustrations of root displacement and soil principal stress. (c) Schematic illustrations of soil displacement for low β and for high β.