> 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/static-loads-fea/prestressing-loads-fea.md).

# Prestressing Loads \[FEA]

Prestressing loads define the application of prestress forces from tendons to the structural model for static analysis. These loads are used in non-staged analysis to apply the effective tendon forces after all losses.

**Load Case:** The analysis case (load case) to which this prestressing load belongs. Typically a load case with the PS (Prestress) load type.

**Tendon:** The tendon object from which the prestress forces are derived. The tendon's geometry, material, and jacking parameters define the force profile along its length. Right-click any field in this spreadsheet for the action *View Tendon Short Term Losses* which displays the tendon force diagram with the jacking parameters adjusted for the current stress level.

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

**Stressing at End:** Indicates whether the tendon is stressed (jacked) from the end. Select Yes to apply the jacking force at the far anchorage. When both ends are stressed, the effective force is the envelope of forces from both jacking operations.

**Instantaneous Elastic Shortening Loss:** Controls whether the elastic shortening loss is included in the prestress force calculation. Elastic shortening occurs when the prestressed member shortens under the applied prestress, reducing the effective force in tendons that were stressed earlier. Select Yes to include this loss.


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