> 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/support-lines-ex1-stg.md).
# Support Lines
This section defines the locations of abutments and piers along the bridge alignment.
{% hint style="info" %}
**Navigation:** Bridge Geometry > Support Lines
For detailed parameter explanations, see the [Support Lines Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/bridge-geometry-stg/support-lines-stg).
{% endhint %}
## Steps
### Step 1: Navigate to Support Lines
Navigate to **Bridge Geometry > Support Lines** in the tree view.
### Step 2: Create First Support Line
Click the **three-dot icon** on the first **Bridge** cell and set it to **BRG1**.
### Step 3: Define All Support Lines
Create support lines at the following stations:
| Support Line | Station (ft) |
| ------------ | ------------ |
| Abut1 | 0 |
| Pier2 | 160 |
| Pier3 | 360 |
| Abut4 | 520 |
Quick Tip: Transverse Offset Direction
Offset values use the PGL (Profile Grade Line) as the reference point.
## Verification
{% hint style="success" %}
The completed support lines are shown below.
{% endhint %}
---
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