| Quantity | Value |
| unit weight of backfill soil (γ) | 16 kN/m3 |
| saturated unit weight of soil (γsat) | 19 kN/m3 |
| internal soil friction angle (f) | 30˚ |
| cohesion constant (c) | 0 |
| angle of wall friction (δ) | 0.67f |
| suction stress parameter (χ) | 0.5 |
| suction stresses (ua − uw) | 10 - 50 kPa |