> 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/precast-i-girder-bridge-workflow/substructure-pig/pier-pig/steel-i-girder-bent-cap-pig/diaphragm-pig.md).

# Diaphragm \[PIG]

The Diaphragm object serves as a connection element between I-Girders . Both the FEM and 3D models are generated based on the parameter definitions listed below.

## Diaphragm

**Girders:** Specify the girders for which the diaphragms will be generated.

**Station on Girders (from Right End):** Assume the right-hand side as the starting point for station definition when viewed up-station from the alignment.

**Thickness:** This parameter is used to specify the thickness of the diaphragm in the bridge’s transverse direction.

**Material:** Assign a material to the diaphragm. Materials can be selected from previously defined options or imported as needed.

**Top Offset (from Bottom of Top Flange):** For a visual representation, refer to the figure below.

**Bottom Offset (from Top of Bottom Flange):** For a visual representation, refer to the figure below.

![image-20240913-125522.png](https://openbrim.atlassian.net/wiki/download/attachments/2575138834/image-20240913-125522.png?api=v2)

## Quantities

**Rebar Density(per cubic yard):** Estimated rebar weight per unit concrete volume for the diaphragm, used by downstream quantity takeoff reports to compute total rebar weight from the diaphragm's concrete volume.


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