> 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/examples/concrete-bridge-examples/example-prestressed-i-girder-concrete-bridge-ex1-pig/bridge-geometry-ex1-pig/girder-layout-ex1-pig.md).

# Girder Layout

This section defines the girder layout by connecting insertion points to form girder lines, and specifying cantilever lengths at girder ends.

{% hint style="info" %}
**Navigation:** Bridge Geometry > Girder Layout

For detailed parameter explanations, see the [Girder Layout Reference](https://docs.openbrim.org/templates/precast-i-girder-bridge-workflow/bridge-geometry-pig/girder-layout-pig).
{% endhint %}

## Steps

### Step 1: Navigate to Girder Layout

Navigate to **Bridge Geometry > Girder Layout** in the tree view.

![Navigation](https://openbrim.atlassian.net/wiki/download/attachments/2235400349/image-20230711-152333.png?api=v2)

![Girder Layout Panel](https://openbrim.atlassian.net/wiki/download/attachments/2235400349/image-20230711-153202.png?api=v2)

### Step 2: Define First Girder Line

Click the **three-dots icon** on the first cell under **Supports** and select insertion points **IP1** and **IP6** to define the first girder line.

### Step 3: Create Remaining Girder Lines

Repeat the process to create girder lines for all girders by selecting the appropriate insertion point pairs.

### Step 4: Set Cantilever Lengths

Enter the **Initial Cantilever Length** and **End Cantilever Length** as **6.5 ft** for each girder.

{% hint style="info" %}
The cantilever length represents the distance between the bearing and girder end. This distance is included in the self-weight computation of the girder.
{% endhint %}

![Cantilever Length](https://openbrim.atlassian.net/wiki/download/attachments/2235400349/image-20230711-154653.png?api=v2)

## Verification

{% hint style="success" %}
After completing these steps, your girder layout should match the view shown below.
{% endhint %}

![Completed Girder Layout](https://openbrim.atlassian.net/wiki/download/attachments/2235400349/image-20230711-154920.png?api=v2)

### Video Walkthrough

This video demonstrates the process of creating the girder layout by selecting insertion points.

![Girder Layout Setup](https://openbrim.atlassian.net/wiki/download/attachments/2235400349/Girderlayout2.gif?api=v2)


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