[Solved] Tunnel designer loses material assignments after loading project in 3D 2018

02 April 2019
Date modified 19 August 2019
Solved since PLAXIS 3D CONNECT Edition V20
Known issue ID SW-37888
Applications PLAXIS 3D 2018.00, PLAXIS 3D 2018.01

Problem description

With the Tunnel designer, among other features, it is possible to define the material of a volume, e.g. when simulating the installation of the shotcrete or the final lining. This is performed in Sequencing mode, in which the tunnel phase steps are defined.

When a project that contains such a definition is being opened in Input program in PLAXIS 3D 2018 any material assignments set in Sequencing mode are lost:

3D 2018 Tunnel designer loses material assignements problem demo

This means that if a new phase is added in Staged construction mode when using the Advance to next tunnel step, it will result in having no material assigned as defined in tunnel designer:

3D 2018 Tunnel designer loses material assignements SC problem demo

Note that no material assigned means that the default soil material will be kept for the specific slice.


This issue is now solved in PLAXIS 3D CONNECT Edition V20

The suggested workaround for the issue with the Tunnel designer in PLAXIS 3D 2018 is only applicable if the project is not reloaded during the process since this is when the issue occurs.

  1. Switch to Structures mode
  2. Select the relevant tunnel and use the right mouse button to Edit it
  3. In the Tunnel designer switch to Sequencing mode
  4. Select the tunnel phase step in which the assignment of a material in a volume is shown as: <not assigned>
  5. Edit the material to the desired data set
  6. Select to Close the Tunnel designer
    Note that there is no need to Generate the tunnel or Generate tunnel phases unless changes in other modes are included.
  7. Switch to Staged construction mode and define any new phases
    Note that any existing phases will be automatically regenerated according to the material selected in step 5.

Be aware that the above steps are required every time you reload the project when it is needed to add new phases in Staged construction or edit the current tunnel definitions.

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