> 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/superstructure-ex1-stg/deck-ex1-stg/cross-section-ex1-stg.md).
# Cross Section
This section defines deck cross-section geometry at key stations along the bridge.
{% hint style="info" %}
**Navigation:** Superstructure > Deck > Cross Section
For detailed parameter explanations, see the [Cross Section Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/superstructure-stg/deck-stg/cross-section-stg).
{% endhint %}
## Steps
### Step 1: Navigate to Cross Section
Navigate to **Deck > Cross Section** in the tree view.
### Step 2: Define Cross-Section Locations
At minimum, define 2 deck cross-sections along the bridge length.
Click the **three-dot icon** on **Support Line** cell and set **Abut1** and **Abut4** with no longitudinal offsets.
### Step 3: Configure Deck Cross Section
Navigate to the **Deck Cross Section** tab.
### Step 4: Assign Girders for Haunches
Pick the **Girders for haunch locations** (G1 and G2).
### Step 5: Enter Cross-Section Dimensions
Enter the following for each deck cross-section:
* **Total Width:** 502 in
Quick Tip: Transverse Offset Direction
Offset values use the PGL (Profile Grade Line) as the reference point.
## Verification
{% hint style="success" %}
The completed cross-sections are shown below.
{% endhint %}
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