> 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/custom-girder-bridge-workflow/superstructure-cg/cip-pre-post-tensioned-girders-cg/girder-basic-variation-cg.md).

# Girder (Basic Variation) \[CG]

A cast-in-place pre/post-tensioned girder whose cross-section is defined by a start and an end section, with the section varying linearly between them. Use **Girder (Advanced Variation)** when the section must follow a more complex variation.

## Girder Parameters

**Girder Layout:** The girder layout line this girder is placed along.

**Girder Start-End Section:** Table defining the girder's section at its start and end. Each row gives the support line, station offset, the assigned section, and the variation flag applied between the control points.

**Material:** Concrete material assigned to the girder.

## FEA

**Supports:** Support lines or objects the girder is supported at in the analytical model.

**Long. Mesh Size:** Maximum finite-element size along the girder (default: 120).

**Expansion joint end releases:** Table of end releases applied at expansion joints along the girder.

**Rigid Section:** Section used for the rigid links that connect the girder to the substructure at support locations.

**Mesh at section edges\[NO=0/YES=1]:** When YES, mesh lines are forced onto the edges of the girder cross-section, so element boundaries line up with section changes (default: NO=0).

**# of Result Extraction St.:** Number of stations along the girder at which composite analysis results are extracted (default: 60).

## Referencing Objects

**Structure States:** Construction stage objects that stage this girder. (Read-only)

**Temporary Supports:** Temporary Support objects that reference this girder. (Read-only)

**Decks:** Deck objects carried by this girder. (Read-only)

**Tendons:** Tendon objects running along this girder. (Read-only)

**Strands:** Strand objects running along this girder. (Read-only)

**Bracings:** Bracing objects connected to this girder. (Read-only)


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