> For the complete documentation index, see [llms.txt](https://docs.enercalc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enercalc.com/efr-user-manual/calculation-types/working-with-beam-calculations/beam-supports13/support-fixity.md).

# Support Fixity

How beam end support fixity is set as fixed, pinned, or free using Revit connection parameters during calculation launch.

In conventional steel beam calculations, ENERCALC SEL provides several options for users to set fixity at beam end supports:

* Fixed: translation and rotation restraint, resulting in both force and moment reactions
* Pinned: translation restraint only, resulting in force reactions
* Free: No restraint, resulting in no reactions

All interior supports are restricted to pinned only.

![](https://4249100372-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgHVzpA9PT0VcuNGp6j39%2Fuploads%2Fgit-blob-29fcf3800f73f6c0efcb439d251e7f3eceb8c7c5%2Fclip0110.png?alt=media)

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ENERCALC for Revit provides the ability to use these same fixity options when launching a beam calculation from the Revit model. The following rules are used to determine fixity during a beam calculation launch:

* All interior supports are set as pinned
* Free ends are inferred when a Revit beam element end location is found without a support
* Supported ends are set as pinned or fixed by reading the native Revit “Start Connection” and “End Connection” parameters.
  * “None” = pinned
  * “Moment Frame” = fixed
  * “Cantilever Moment” = fixed

![](https://4249100372-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgHVzpA9PT0VcuNGp6j39%2Fuploads%2Fgit-blob-3c7180d72fde78c58bbc87877c0dc99bfff80470%2Fclip0112.png?alt=media)

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