Bishop effective stress
In unsaturated soil the effective stress depends on how much of the pore space is filled with water. This tab selects how that dependence is evaluated.
The tab applies to three-phase materials only, and for them a method must be chosen.
| Method | Requires |
|---|---|
| Effective-Saturation | — |
| Saturation | — |
| Crude-Switch | — |
| Lu-Likos | κ and S^wr |
| Power-Saturation | κ |
The two parameter fields are always visible, but only become editable for the methods that use them.
Validation
For a three-phase material a method must be selected, and the parameters of the chosen method must be filled. Pressing Apply & Save with something missing shows a warning naming the problem, and the material stays open so it can be corrected.
The methods are described under Bishop effective stress in the numgeo reference manual.