In the above mentioned versions, the predefined unsaturated Van Genuchten parameters of the Hypres Topsoil Medium fine dataset for gl and gn are not correctly set internally.
This is only an issue for this predefined data set:
For this case, the parameters gl and gn are incorrectly set to 0.5884 and 1.235 respectively. The correct values should be gl = -0.5884 and gn = 1.2539, as written in the section about the Groundwater tab sheet in the PLAXIS Reference Manual.
This issue is now resolved in PLAXIS 3D 2016.00, PLAXIS 3D Classic and PLAXIS 2D 2017.00: the values for the internal Van Genuchten parameters gl and gn are now correctly defined.
For older versions, to solve this issue: when using the dataset for Hypres (Van Genuchten) Topsoil Medium fine, user are advised to switch to: