The following known issues exist in relation to (external) waterloads on plates coming from inactive clusters. For each known issue also a typical example is given.
In the situation of a plate that is adjacent to an inactive cluster with a cluster defined phreatic level, the external waterloads in this inactive cluster are still determined by the general phreatic water level. This means that the actual external waterloads acting on the plate element coming from this deactivated cluster are not according to the expectations. Note that Output displays the correct (actually used) external waterload on the plate for this situation.
For the situation where on both sides of a plate element clusters are inactive and one of the inactive clusters is set to “dry” in the water conditions mode, the external water loads in the other inactive cluster may also be set to zero. Note that Output does not display the correct (actually used) external water load for this situation!
A possible work around for the above mentioned situations is to create a separate distributed load representing the external waterloads. This load should be activated in those phases where you want the external waterloads to act on your structure.
Users who are uncertain of model results or have additional questions or remarks are requested to contact the Plaxis support department: https://apps.bentley.com/srmanager/ProductSupport
This has been fixed since PLAXIS 2D 2011.00