This Plug-In allows to sum the reaction forces of many nodes in postprocessing for every increment of each (active) general step. Afterwards xy-plots can be created from the generated curves, so you can see the evolution of the overall reaction force at a boundary condition, e.g.

This Plug-In isn’t needed that often. Some time ago Abaqus/CAE was enhanced to include a “Sum” operator when you extract the xy-data from the Field Output. This built-in operation needs some more mouse clicks, but does the job more efficiently when the number of nodes is small (app. <10k). Beyond that my Plug-In is typically faster. I’m accessing the bulkDataBlocks of RF for the affected instances and use Numpy and Pythons izip-function (from itertools) to transform them into a dictionary. This is then quite fast to access. Still it might need some seconds when you use it with a large number of nodes and many result frames.

Additionally my Plug-In provides a fast and easy option to output the sum of reaction forces for the current frame only and it also provides two different methods for the magnitude calculation.

Other built-in alternatives to the Plug-In are the usage of a coupling, in case you know the need already in preprocessing and a coupling is not affecting the behavior of the model. Also Report-> Field Output can sum data into the generated ASCII file.

The short video shows my Plug-In with an example and also the built-in option for generating xy-data from Field Output. In Abaqus/CAE go to Plug-ins -> About Plug-ins… to get more information. The files are attached.
 

Additional remarks:
This Plug-In is not an official Dassault Systemes/Simulia product. I’ve created it on my own and initially only for me. The UI is built with the RSG Plug-in. This brings some limitations regarding catching user errors and displaying messages.

You can find more Plug-Ins for Abaqus/CAE in the wiki of this community (Link) and in the DS Knowledge Base (Link1, Link2).

Edit: You can find an updated version that also works with Python 3 in Abaqus 2024 in my Github account (Link).

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