> 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/openbrimfea/loads-fea/staged-construction-fea/prestressing-fea.md).

# Prestressing \[FEA]

Prestressing entries define the application of tendon stressing operations at specific construction stages. This allows the analysis to account for the correct sequence of tendon stressing during staged construction, including time-dependent losses.

**Stage:** The construction stage at which the tendon stressing operation occurs. The prestress forces are applied during the analysis of this stage.

**Tendon:** The tendon object to be stressed at this stage. Select from the tendons defined in the project. The tendon's geometry, material, and friction properties are used to compute the effective prestress force.

**Stressing at Start:** Indicates whether the tendon is stressed (jacked) from the start end at this stage. Select Yes to apply the jacking force at the start anchorage.

**Stressing at End:** Indicates whether the tendon is stressed (jacked) from the end at this stage. Select Yes to apply the jacking force at the far anchorage. Stressing from both ends is common for long tendons to minimize friction losses.

**Instantaneous Elastic Shortening Loss:** Controls whether the elastic shortening loss is included in the prestress force calculation at this stage. Elastic shortening occurs when the concrete member shortens under the applied prestress, reducing the effective force in previously stressed tendons.


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