> 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/concrete-u-girder-bridge-workflow/loading-cug/loads-cug/earth-pressure-cug.md).

# Earth Pressure \[CUG]

Earth-pressure loads in OpenBrIM model the horizontal pressure exerted by retained soil or a live-load surcharge on abutment back walls and the footings they rest on. The Abutment Earth Pressure library object converts an active earth-pressure coefficient and backfill unit weight into a triangular (earth pressure) or uniform (live-load surcharge) surface load that is applied to the selected abutment at a chosen construction stage.

For a detailed explanation of each library object, refer to the relevant section of the documentation.


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