|Date modified||24 October 2016|
|Known issue ID||21810|
|Applications||PLAXIS 2D 2012.00, PLAXIS 2D 2012.01, PLAXIS 2D AE.00, PLAXIS 2D AE.01, PLAXIS 2D AE.02, PLAXIS 2D Classic|
When performing an updated mesh calculation including updated water pressures for a model with deactivated soil elements that have different water pressures compared to the adjacent active soil clusters, the results incorrectly include external water loads on the cluster borders based on the pore pressures from these adjacent active cluster borders.
A practical case in which this goes wrong is for example an excavation model where the excavation pit is set to dry, while the surrounding soil still has a high water table. The preview of the phase correctly shows a dry excavation pit, but the results incorrectly show a high water level inside the excavation level equal to the phreatic level of the surrounding soil:
Figure 1. Example of incorrect external water loads in an excavation problem
This issue is now solved since PLAXIS 2D 2015.00.
For PLAXIS 2D AE and earlier no work around is available for this problem when using updated water pressures. Users are advised to switch off updated water pressures for the above mentioned cases.