# Materials

This section defines material properties for structural steel, reinforcing steel, and concrete used in the Steel I Girder Bridge model.

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**Navigation:** Properties > Materials

For detailed parameter explanations, see the [Materials Reference](https://docs.openbrim.org/templates/steel-i-girder-bridge-workflow/properties-sig/materials-sig).
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## Steps

### Step 1: Navigate to Materials

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

### Step 2: Import Structural Steel Materials

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

Import the following steel materials from the OpenBrIM Library:

| Material Path                                                                | Material Name |
| ---------------------------------------------------------------------------- | ------------- |
| OpenBrIM Bridge Objects > Steel Material Database (US) > Structural Steel    | A709\_50      |
| OpenBrIM Bridge Objects > Steel Material Database (US) > Structural Steel    | A709\_50W     |
| OpenBrIM Bridge Objects > Steel Material Database (US) > Reinforcement Steel | A615\_60      |

![Import Material](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20231003-115132.png?api=v2)

![Material Selection](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20221008-135440.png?api=v2)

### Step 3: Import Concrete Materials

Import the following concrete materials:

| Material Path                                                         | Material Name                            |
| --------------------------------------------------------------------- | ---------------------------------------- |
| OpenBrIM Bridge Objects > Concrete Material Database (US) > US AASHTO | Fc\_4ksi                                 |
| OpenBrIM Bridge Objects > Concrete Material Database (US) > US AASHTO | Fc\_4ksi (rename to **Fc\_4ksiforDeck**) |

### Step 4: Assign Stress-Strain Models for Concrete

Click the **three-dots icon** on **Fc\_4ksi** and select **Edit**.

Set **Stress/Strain Model** to **Mander Concrete**.

![Edit Material](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20240927-120556.png?api=v2)

![Mander Concrete](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20221115-153742.png?api=v2)

Repeat for **Fc\_4ksiforDeck**.

### Step 5: Assign Stress-Strain Model for Reinforcement

For **A615\_60**, set **Stress/Strain Model** to **Bilinear Steel**.

![Bilinear Steel](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/trainingss.drawio%20-%202022-10-10T112156.014-20221010-082156.png?api=v2)

### Step 6: Create Rigid Material

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

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Set the **unit weight** of rigid materials to **0** to avoid adding artificial mass to the model.
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![Rigid Material](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20240927-121241.png?api=v2)

### Step 7: Create FcCube\_NoStiffness Material

Add another material named **FcCube\_NoStiffness** for components where stiffness should be excluded.

![FcCube NoStiffness](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20240927-121643.png?api=v2)

<details>

<summary><strong>Quick Tip:</strong> Stress-Strain Curves</summary>

Each material includes a default stress-strain curve for section capacity calculations. To view or modify:

1. Click the **three-dots icon** on a material and select **Edit**
2. Select the **Stress/Strain Model** from the dropdown
3. The corresponding curve updates automatically

</details>

## Verification

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After completing these steps, the material definitions should match the view shown below.
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![Completed Materials](https://openbrim.atlassian.net/wiki/download/attachments/2101706924/image-20240927-121919.png?api=v2)

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To view the entire procedure explained on this page, please watch the recorded video below.
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{% embed url="<https://openbrim.atlassian.net/wiki/download/attachments/2101706924/Properties-Material%20SIGEX1.mp4?api=v2>" %}
Properties-Material SIGEX1
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