> 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/rectangular-ex1-stg.md).
# Rectangular
This section defines rectangular footing geometry for standard pier columns.
{% hint style="info" %}
**Navigation:** Substructure > Foundation > Rectangular
For detailed parameter explanations, see the [Rectangular Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/substructure-stg/foundation-stg/rectangular-stg).
{% endhint %}
## Steps
### Step 1: Navigate to Rectangular Foundation
Navigate to **Foundation > Rectangular** in the tree view.
### Step 2: Assign Substructure
Click the **three-dot icon** on the **Substructure** cell and select **Column1** and **Column2**.
### Step 3: Define Footing Dimensions
Enter the footing dimensions as shown in the table:
| Parameter | Description |
| ------------------------- | --------------------------------- |
| Footing Width \[ft] | Width of the rectangular footing |
| Footing Length \[ft] | Length of the rectangular footing |
| Longitudinal Offset \[ft] | Offset along alignment |
### Step 4: Assign Material
Click the **three-dot icon** on the **Material** cell and select **Fc\_5ksi** concrete material for the rectangular footings.
### Step 5: Configure FEM Settings
Navigate to the **FEM** tab and select **RigidSection** for the Rigid Section column.
Quick Tip: Foundation Offsets
**Longitudinal Offset:** Offsets the foundation along the alignment.
**Transverse Offset:** Offsets the foundation on the y-axis perpendicular to the alignment.
**Rotation:** Rotates the XY plane.
## Verification
{% hint style="success" %}
The completed rectangular footings are shown below.
{% endhint %}
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