> 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/bridge-geometry-ex1-stg/roadway-alignment-ex1-stg.md).
# Roadway Alignment
This section defines the horizontal, vertical, and transverse alignment for the Steel Tub Girder Bridge.
{% hint style="info" %}
**Navigation:** Bridge Geometry > Roadway Alignment
For detailed parameter explanations, see the [Roadway Alignment Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/bridge-geometry-stg/roadway-alignment-stg).
{% endhint %}
## Steps
### Step 1: Navigate to Roadway Alignment
Navigate to **Bridge Geometry > Roadway Alignment** in the tree view.
### Step 2: Set Start Station
Enter **Start Station** as **0**.
### Step 3: Open Alignment Editor
Click the **three-dot icon** on the cell and select **Editor**.
### Step 4: Add Horizontal Curve
Click the **+** icon next to **Horizontal** to add a circular segment.
### Step 5: Enter Curve Parameters
Enter the following parameters:
* **Length:** 520 feet
* **Radius:** 700 feet
* **Direction:** Towards Right
Quick Tip: Vertical Alignment
Modify vertical data (grades and elevations) in the **Vertical** tab. In this example, vertical data is set to 0.
### Step 6: Define Start Cross-Section
Click the **+** icon next to **Transverse** to add a cross-section at Station 0.
### Step 7: Enter Station 0 Parameters
Enter the following:
* **Station:** 0 ft
* **Left Edge to PGL:** 20 ft
### Step 8: Add Section Component
Click the **+** icon next to **At Sta+0** to add a section component with:
* **Width:** 40 ft
* **Slope:** -5%
### Step 9: Define End Cross-Section
Add another transverse section at Station 520:
* **Station:** 520 ft
* **Left Edge to PGL:** 20 ft
* **Width:** 40 ft
* **Slope:** -5%
### Step 10: Accept Changes
Click **Accept** to save the alignment.
Quick Tip: Viewing Roadway Surface
If the 3D alignment doesn't appear, click **Zoom Extents** or enable **Show Roadway Surface** in Settings.
## Verification
{% hint style="success" %}
The completed bridge alignment is shown below.
{% endhint %}
---
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