> 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/concrete-bridge-examples/example-concrete-u-girder-bridge/superstructure-attachments-ex1-cug/f-shape-barrier-ex1-cug.md).
# F Shape Barrier
This section defines F-shape concrete barriers on both sides of the bridge deck.
{% hint style="info" %}
**Navigation:** Superstructure Attachments > F Shape Barrier
For detailed parameter explanations, see the [F Shape Barrier Reference](https://docs.openbrim.org/templates/concrete-u-girder-bridge-workflow/superstructure-attachments-cug/barrier-cug).
{% endhint %}
## Steps
### Step 1: Navigate to F Shape Barrier
Navigate to **Superstructure Attachments > F Shape Barrier** in the tree view.
### Step 2: Assign Deck Reference
Define barriers on both left and right sides of the deck:
1. Click the **three-dots icon** on **Deck** cell
2. Set **Deck1** for both barrier entries
### Step 3: Select Orientation
Select the **Orientation** for each barrier (Left or Right side).
### Step 4: Assign Material
Set the concrete **Material** to **Fc\_4ksi** for both barriers.
### Step 5: Define Transverse Offsets
Enter the **Start Transverse Offset** and **End Transverse Offset** values.
Quick Tip: Transverse Offset Direction
Offset values use the PGL (Profile Grade Line) as the reference point.
### Step 6: Configure Dimensions
Navigate to the **Dimension** tab and enter the F Shape Barrier dimension parameters.
Quick Tip: Barrier Function in Analysis
Barriers are included in the FE model to distribute wind forces across the structure.
## Verification
{% hint style="success" %}
The completed F Shape Barriers are shown below.
{% endhint %}
---
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