Problem description

When inspecting a Deformed mesh plot which includes connections of plates and/or geogrid elements in combination with interfaces in PLAXIS 2D AE you may get the feeling that something is wrong, as it seems the plates and/or geogrids are not correctly connected. See for example Figure 1 below.

Figure 1: Large interface scale factor (PLAXIS 2D AE)

Figure 2: Small interface scale factor

However please note that this is only a graphical issue in PLAXIS 2D AE. The calculation kernel uses the correct connections. The confusion comes from the fact that Output is wrongly taking the “offset of interface nodes” to plot the deformed plates and/or geogrids. Interfaces consist of so called node pairs (also see the related article on Soil-Structure interaction) and in Output we use by default a relatively large scale factor on these node pairs, such that there graphically is a distance between the nodes of the node pairs although in reality there is not.

Solution

This issue is now solved since PLAXIS 2D 2015.00

To correctly show the deformed mesh in PLAXIS 2D AE we can adjust the "interface scale factor". We can do this by:

1. first switching to the Connectivity plot via the menu: Mesh > Connectivity plot (Ctrl+0).
2. Now select from the toolbar: Scale factor > Manual scale and enter a very small value (or just zero)
3. and then switch back via the menu to the deformed mesh plot: Deformations > Deformed mesh (Ctrl+1).