> 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/properties-ex1-stg/sections-ex1-stg.md).
# Sections
This section defines cross-sectional shapes and reinforcement for substructure components.
{% hint style="info" %}
**Navigation:** Properties > Sections
For detailed parameter explanations, see the [Sections Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/properties-stg/sections-stg).
{% endhint %}
## Steps
### Step 1: Navigate to Sections
Navigate to **Properties > Sections** in the tree view.
### Step 2: Import Rectangle Section
Click the **three-dot icon** and select **Import Section**. Select **OpenBrIM Bridge Objects > Basic Sections > Basic Shapes > Rectangle**.
### Step 3: Create Substructure Sections
Create the following rectangular sections:
| Section Name | Width (in) | Depth (in) | Material |
| ------------------ | ---------- | ---------- | -------- |
| HammerHeadSec | 60 | 84 | Fc\_4ksi |
| HalfHammerHeadSec1 | 66 | 54 | Fc\_4ksi |
| HalfHammerHeadSec2 | 66 | 125 | Fc\_4ksi |
| ColSec\_P2 | 72 | 72 | Fc\_5ksi |
| ColSec\_P3 | 204 | 78 | Fc\_5ksi |
| PileSec | 24 | 24 | Fc\_5ksi |
### Step 4: Import Steel Sections
Import AISC steel sections:
| Section | Library Path | Material |
| ------------ | ------------------------------------------------------------- | --------- |
| AISCWT6X29 | OpenBrIM Bridge Objects > AISC Steel Shape Database > WT Type | A709\_50W |
| AISCL6X6X7/8 | OpenBrIM Bridge Objects > AISC Steel Shape Database > L Type | A709\_50W |
### Step 5: Create Rigid Section
Create a section named **RigidSection** and assign **RigidMaterial**.
### Step 6: Add Reinforcement to Sections
For each concrete section, open the Section Editor and add reinforcement:
1. Click the **three-dots icon** on the section row
2. Click the **+** icon and select **Rebar**
3. Configure rebar parameters (Profile, Material, Reference Edge, Spacing, etc.)
4. Click **Add**
Quick Tip: HammerHeadSec Reinforcement
For HammerHeadSec, add reinforcement on all four edges:
* **Top:** ASTMA615No10, A615\_60, 7 bars @ 8" spacing, 2 rows
* **Bottom:** ASTMA615No10, A615\_60, 7 bars @ 8" spacing, multiple rows at different depths
* **Left/Right:** ASTMA615No10/No8, A615\_60, 9 bars @ 6" spacing
Quick Tip: Column Section Reinforcement
For column sections (ColSec\_P2, ColSec\_P3), add reinforcement on all four edges using ASTMA615No11 bars with A615\_60 material.
## Verification
{% hint style="success" %}
The completed section definitions are shown below.
{% endhint %}
---
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