> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/templates/spliced-i-girder-bridge-workflow/construction-spig/superstructure-deconstruction-spig/girder-deconstruction-spig.md).

# Girder Deconstruction \[SPIG]

## Girder Deconstruction

For rehabilitation projects, after constructing the existing structure, users can remove some parts of the girder. The OpenBrIM FEA engine automatically calculates load distribution to the bearings based on stiffness and the unbalanced load vector after deconstruction.

**Stage:** In this stage, the girder’s analytical model will be deconstructed, and the unbalanced load vector will be computed and redistributed throughout the structure.

**Girders:** Choose the girders for the deconstruction.

**Girder Start Station:** Station along the PGL at which the deconstructed portion of the girder begins.

**Girder End Station:** Station along the PGL at which the deconstructed portion ends. The FE engine removes the girder segment between Girder Start Station and Girder End Station and redistributes the unbalanced load.


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