Figure 1.
Changes in peak strength with variable initial void ratio according to critical state soil mechanics, after Atkinson [19]. Top plot: effective stress versus shear stress, bottom plot: effective stress versus void ratio
Figure 2.
Geometry, finite element discretization and boundary conditions of the modelled vegetated slope
Table 1.
List of soil parameters
| Parameter | Symbol | Value | Unit |
|---|---|---|---|
| Dry unit weight | γd | 12.95 | kN/m3 |
| Poisson's ratio | ν | 0.3 | - |
| Plastic compressibility | λ | 0.145 | - |
| Elastic compressibility | κ | 0.0097 | - |
| Slope of the critical state line | M | 1.0 | - |
| Saturated permeability | ks | 5.00E-06 | m/s |
| Initial void ratio | eo | 0.8 | - |
| Van Genuchten’ sparamters: | |||
| a | 0.7 | kPa | |
| n | 2.16 |
Table 2.
Values of the factor of safety for different combinations of root parameters
| Rp | FOS | |
|---|---|---|
| 1.0 | 0.5 | 1.474 |
| 2.0 | 0.5 | 1.477 |
| 3.0 | 0.5 | 1.481 |
| 3.0 | 1.0 | 1.481 |
| 3.0 | 1.5 | 1.487 |
| 4.0 | 1.5 | 1.494 |
Figure 3.
Values of the factor of safety calculated for different durations of the rainfall application. Results obtained for the bare reference slope and the vegetated slope
Figure 4.
Contour of the square root of the second invariant of the deviator strain at the end of the strength reduction step for the rainfall duration of 45000 s (12.5 h) for the reference slope, presented on a deformed mesh
Figure 5.
Contour of the square root of the second invariant of the deviator strain at the end of the strength reduction step for the rainfall duration of 45000 s (12.5 h) for the reference vegetated slope, presented on a deformed mesh