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# Plate Girder
This section defines the steel plate girder geometry with station-dependent plate dimensions for flanges and webs.
{% hint style="info" %}
**Navigation:** Superstructure > Steel Girders > Plate Girder
For detailed parameter explanations, see the [Plate Girder Reference](https://docs.openbrim.org/templates/steel-i-girder-bridge-workflow/superstructure-sig/steel-girders-sig/plate-girder-sig).
{% endhint %}
## Steps
### Step 1: Assign Girder Layout
Click the **three-dots icon** on the **Girder Layout** cell and select a layout.
### Step 2: Open Top Flange Width Editor
Click the **three-dots icon** on the **Top Flange Width** cell and select **Edit (Spreadsheet)**.
### Step 3: Set Start Station
Enter the **Start Station** as **0**.
### Step 4: Understanding Station Parameters
When entering station-dependent dimensions:
* If you enter **Length**, the **End Station** and **Station Difference** are calculated automatically
* If you enter **End Station**, the **Length** and **Station Difference** are calculated automatically
### Step 5: Enter Top Flange Width Data
Enter the following station-dependent values for **Top Flange Width**:
| Length (ft) | Top Flange Width (in) |
| ----------- | --------------------- |
| 113.3 | 15 |
| 22.9 | 21 |
| 20.0 | 21 |
| 20.0 | 21 |
| 21.1 | 21 |
| 123.0 | 15 |
| 21.1 | 21 |
| 20.0 | 21 |
| 20.0 | 21 |
| 22.9 | 21 |
| 113.3 | 15 |
### Step 6: Define Other Plate Dimensions
Using the same spreadsheet method, define station-dependent values for:
* **Top Flange Thickness**
* **Web Depth**
* **Web Thickness**
* **Bottom Flange Width**
* **Bottom Flange Thickness**
* **Haunch Thickness**
* **Additional Haunch Width**
### Step 7: Assign Materials
Click the **three-dots icon** on material cells and select **A709\_50** for:
* **Top Flange Material**
* **Web Material**
* **Bottom Flange Material**
Quick Tip: Importing Materials
If no material is available to select:
1. Click the **three-dots icon** and select **Import Material**
2. Select the material from the library and click **Import**
### Step 8: Configure FEA Settings
Navigate to the **FEA Settings** tab. Keep default parameters or adjust mesh settings as needed.
## Verification
{% hint style="success" %}
The completed plate girder model is shown below.
{% endhint %}
Quick Tip: Show Model View
1. Click the arrow button above the **Analysis** button in the upper-left corner
2. Click **Model** to display the 3D model
Quick Tip: Show FEA View
1. Click the arrow button above the **Analysis** button in the upper-left corner
2. Click **FEA** to display the finite element mesh
{% hint style="success" %}
To view the entire procedure explained on this page, please watch the recorded video below.
{% endhint %}
{% embed url="" %}
SIG EX1 Plate Girder
{% endembed %}
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