Application	PLAXIS 3D
Version	PLAXIS 3D CONNECT Edition V20
Date created	13 October 2020
Date modified	13 October 2020

In PLAXIS 3D, a custom connection can be created in Staged construction mode between two plates or between a beam and a plate.

However, it may happen that, due to different reasons mentioned below, the created custom connection is considered invalid and requires to be removed from the project before performing the calculation.

Handling of invalid connections with a Python script

In PLAXIS Input, a connection is considered invalid when:

• The reference and the custom parts are not sharing any nodes (i.e. they have no common sides)
• No interface is assigned to the surface with a plate representing the Reference part in the connection

In case of an invalid connection an error message will appear when the Calculate button  is clicked:

Figure1. Error feedback for an invalid custom connection

When using the PLAXIS Remote scripting API with the Python wrapper, it is possible to automate the process of removing any invalid custom connections present in a project.

The suggested Python script can perform the following actions on any invalid custom connection(s):

• Identify them using the checkcalculationconditions command
• Select them, in case changes need to be applied to the connection parts
• Delete them using easygui Python module

Usage instructions for Python script

• Download the file (use Save As...).
• Copy the connections_check.py file to this folder:
  <PLAXIS 3D installation folder>\pytools\input
• By default, the installation folder for PLAXIS 3D is:
  C:\Program Files\Bentley\Geotechnical\PLAXIS 3D CONNECT Edition V20\
• Open a PLAXIS 3D project that contains custom connections.
• In the Expert menu, go to Python > Run Python tool. Here you should see the name of Python file.
• When selecting it, the script will be executed, the invalid connections will be identified, will be selected in GUI and it will be possible to delete them.
• When you do not have access rights to add the script in this folder, alternatively, you can choose to use Expert menu > Run Python script > Open... to manually open and run the file.

Version

The script is tested with PLAXIS 3D CONNECT Edition V20.04 with Python 3.7.4