> 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-i-girder-bridge-ex1-sig/properties-ex1-sig/sections-ex1-sig.md).

# Sections

This section defines cross-sectional shapes for pier caps, columns, piles, cross-frames, and barriers.

{% hint style="info" %}
**Navigation:** Properties > Sections

For detailed parameter explanations, see the [Sections Reference](https://docs.openbrim.org/templates/steel-i-girder-bridge-workflow/properties-sig/sections-sig).
{% endhint %}

## Steps

### Step 1: Navigate to Sections

Navigate to **Properties > Sections** in the tree view.

![Navigate to Sections](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20221008-104738.png?api=v2)

### Step 2: Import Pier Cap Mid Section

Click the **three-dots icon** on the first cell under **Name** and select **Import Section**.

Select **OpenBrIM Bridge Objects > Basic Sections > Basic Shapes > Rectangle**.

Enter the following dimensions:

* Width: **96 in**
* Depth: **96 in**

Click **Import** and rename as **PierCapRec\_Mid**. Assign material as **Fc\_4ksi**.

### Step 3: Import Pier Cap Taper Section

Repeat the import process for another rectangle:

* Width: **96 in**
* Depth: **48 in**

Rename as **PierCapRec\_Taper**. Assign material as **Fc\_4ksi**.

### Step 4: Import Pier Column Section

Import another rectangle:

* Width: **80 in**
* Depth: **80 in**

Rename as **PierColumnRec**. Assign material as **Fc\_4ksi**.

### Step 5: Import Circular Pier Column Section

Import a circular section:

* Radius: **21 in**

Rename as **PierColumnCircle**. Assign material as **Fc\_4ksi**.

![Circular Section](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20221008-133928.png?api=v2)

### Step 6: Import Pile Section

Import another circular section:

* Radius: **20 in**

Rename as **PileCircle**. Assign material as **Fc\_4ksi**.

### Step 7: Import Cross-Frame Section

Import from **OpenBrIM Bridge Objects > AISC Steel Shape Database > L Type > AISCL8X8X3/4**.

Assign material as **A709\_50**.

![L Section](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/tempsnip4.png?api=v2)

### Step 8: Create Rigid Section

Add a new row and create **RigidSection** for rigid connections.

Assign material as **RigidMaterial**.

![Rigid Section](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20240927-132339.png?api=v2)

### Step 9: Import Barrier Section

Import from **OpenBrIM Bridge Objects > Barrier Sections > F Shape Barrier > F Shape**.

Assign material as **FcCube\_NoStiffness**.

![Barrier Section](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20250113-144547.png?api=v2)

## Verification

{% hint style="success" %}
After completing these steps, the section definitions should match the view shown below.
{% endhint %}

![Completed Sections](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20240928-141058.png?api=v2)

{% hint style="success" %}
To view the entire procedure explained on this page, please watch the recorded video below.
{% endhint %}

{% embed url="<https://openbrim.atlassian.net/wiki/download/attachments/2101805143/Properties%20Section.mp4?api=v2>" %}
Properties Section
{% endembed %}

***

## Section Rebar Detailing

For substructure design, rebar detailing can be defined within each section using the Section Editor.

### PierCapRec\_Mid Rebar Detailing

1. Click the **three-dots icon** on **PierCapRec\_Mid** and select **Section Editor**
2. Click the **+** icon and select **Rebar**
3. Add top rebar row: **14 rebars**, Profile: **ASTMA615No9**, Material: **A615\_60**
4. Add bottom rebar row: **9 rebars**, Profile: **ASTMA615No8**, Material: **A615\_60**
5. Use **Points Spreadsheet** to set exact rebar coordinates

![Section Editor](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/tempsnip5.png?api=v2)

![Add Rebar](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20250113-150523.png?api=v2)

![Rebar Properties](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20250113-152502.png?api=v2)

{% embed url="<https://openbrim.atlassian.net/wiki/download/attachments/2101805143/Section-Rebar%20definition.mp4?api=v2>" %}
Section-Rebar definition
{% endembed %}

### PierCapRec\_Taper Rebar Detailing

1. Open Section Editor for **PierCapRec\_Taper**
2. Add **7 rows of 2 rebars** at the top (Profile: **ASTMA615No9**)
3. Add **1 row of 9 rebars** at the bottom (Profile: **ASTMA615No8**)

![Taper Section Editor](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20221115-164319.png?api=v2)

![Taper Rebars](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20250113-154429.png?api=v2)

### PierColumnRec Rebar Detailing

1. Open Section Editor for **PierColumnRec**
2. Add top and bottom rows: **10 rebars each** (Profile: **ASTMA615No9**)
3. Add side rows: **7 rebars each** (Profile: **ASTMA615No9**)

![Column Rebars](https://openbrim.atlassian.net/wiki/download/attachments/2101805143/image-20250113-154647.png?api=v2)

<details>

<summary><strong>Quick Tip:</strong> Section Properties</summary>

OpenBrIM automatically calculates section properties when **Compute Properties from Shape Parameters** is set to **Yes**:

* Area, Shear Area Y/Z
* Inertia Y/Z
* Torsion Constant

Use the **lock icon** to view computed properties used in FEA.

![Properties Lock](https://openbrim.atlassian.net/wiki/download/attachments/2124677142/image-20230306-211625.png?api=v2)

</details>

<details>

<summary><strong>Quick Tip:</strong> Section Editor Features</summary>

The Section Editor supports:

* **Polygon**: Draw custom shapes by clicking coordinates
* **Template**: Import standard shapes (rectangle, circle, I-beam, etc.)
* **Rebar**: Add reinforcement layouts (line or circular)
* **Tendon**: Add prestressing tendons

Use **Points Spreadsheet** to precisely define coordinates for any element.

</details>


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