With respect to rebound for a non-linear material, when unloading occurs, strain is calculated using Cr instead of Cc. Cr is generally less than Cc so you will get less displacement during unloading than you would for loading. The same is true for the secondary consolidation. When unloading, Car is used instead of Ca.
Poisson's ratio is only applicable if you are using mean 3D stress, multiple layer or Westergaard stress computation, or rigid loading.
The response below applies only to groundwater modeled with the piezo lines or groundwater grids. If the groundwater is modeled using the pore water pressure function option, all changes in pwp must be explicitly modeled.
When an excavation is added that extends below the water table, the water table is locally dropped to the bottom of the excavation. This is to ensure that the excavation is dry and not full of water. Query points inside the excavation will see a drop in pore water pressure. Query points outside of the excavation are unaffected by the drop in the water table.
This approach tends to overestimate the settlement (it gives a conservative answer), compared with what would be observed for a true three-dimensional groundwater analysis, since this approach does not account for horizontal water flow from areas of higher pressure (outside of the excavation) to areas of lower pressure (under the excavation).
A Time Point Query only computes the time based on the current load state, at the time point stage. If the load changes after the time point stage (i.e. if loads are added or removed) the time point is not aware of the change in load state after the time point stage. Therefore if you have staged loading, you must add the time point at the final loading stage that you wish to consider.