> 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/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/substructure-ex1-stg/foundation-ex1-stg/custom-ex1-stg.md).

# Custom

This section defines custom-shaped footing geometry for special pier configurations.

{% hint style="info" %}
**Navigation:** Substructure > Foundation > Custom

For detailed parameter explanations, see the [Custom Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/substructure-stg/foundation-stg/custom-stg).
{% endhint %}

## Steps

### Step 1: Navigate to Custom Foundation

Navigate to **Foundation > Custom** in the tree view.

![Custom foundation navigation](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-110631.png?api=v2)

### Step 2: Assign Substructure

Click the **three-dot icon** on the **Substructure** cell and select **Column3**.

### Step 3: Define Footing Points

Click the **three-dot icon** on the **Footing Points** cell and select **Edit**.

Enter the footing point coordinates for **F1** (Column3) as shown in the spreadsheet.

![Footing points edit](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-111130.png?api=v2)

![Footing points data](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-111620.png?api=v2)

### Step 4: Configure Dimensions and Offsets

Enter the following parameters:

| Parameter                 | Description                       |
| ------------------------- | --------------------------------- |
| Thickness \[ft]           | Footing thickness                 |
| Longitudinal Offset \[ft] | Offset along alignment            |
| Transverse Offset \[ft]   | Offset perpendicular to alignment |

![Footing parameters](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-112131.png?api=v2)

### Step 5: Assign Material

Click the **three-dot icon** on the **Material** cell and select **Fc\_5ksi** concrete material for the custom footing.

![Material assignment](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-112203.png?api=v2)

### Step 6: Configure FEM Settings

Navigate to the **FEM** tab and select **RigidSection** for the Rigid Section column.

![FEM settings](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-112348.png?api=v2)

## Verification

{% hint style="success" %}
The completed custom footing is shown below.
{% endhint %}

![Custom footing 3D view](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-113049.png?api=v2)

![Custom footing plan view](https://openbrim.atlassian.net/wiki/download/attachments/2169176092/image-20230222-113119.png?api=v2)


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