> 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/substructure-ex1-cug/pier-ex1-cug/pier-cap-ex1-cug.md).

# Pier Cap

This section defines the pier cap geometry, sections, and FEA settings for intermediate supports.

{% hint style="info" %}
**Navigation:** Substructure > Pier > Pier Cap

For detailed parameter explanations, see the [Pier Cap Reference](https://docs.openbrim.org/templates/concrete-u-girder-bridge-workflow/substructure-cug/pier-cug/pier-cap-cug).
{% endhint %}

## Steps

### Step 1: Navigate to Pier Cap

Navigate to **Pier > Pier Cap** in the tree view.

![Pier Cap navigation](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-122639.png?api=v2)

### Step 2: Assign Locations

Click the **three-dots icon** on the **Location** cell and select the support lines:

| Pier Cap | Location |
| -------- | -------- |
| PierCap1 | SL2      |
| PierCap2 | SL3      |

{% hint style="info" %}
Since PierCap1 and PierCap2 are identical, enter the same parameter values for both.
{% endhint %}

![Location Assignment](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-123329.png?api=v2)

![Pier Cap Parameters 1](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-123623.png?api=v2)

![Pier Cap Parameters 2](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-123657.png?api=v2)

### Step 3: Define Section Geometry

Click the **three-dots icon** on **Straight - Tapered Section / Length** and select **Edit**.

Configure the section parameters:

| Parameter      | Value                        |
| -------------- | ---------------------------- |
| Start Section  | PCSec                        |
| End Section    | PCSec                        |
| Section Length | 45 ft (along Y-Y from right) |

### Step 4: Set Slope Option

Navigate to the **General** tab and set **Slope Option** to **Alignment**.

![Slope Option](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-124532.png?api=v2)

### Step 5: Set Elevation Offset

Enter the **Top Elevation Offset from Alignment** value as **-9.00 ft**.

<details>

<summary><strong>Quick Tip:</strong> Transverse Offset Direction</summary>

Offset values use PGL (Profile Grade Line) as the reference point.

![Offset Reference](https://openbrim.atlassian.net/wiki/download/attachments/2104689432/image-20230216-130246.png?api=v2)

</details>

### Step 6: Configure FEA Settings

Navigate to the **FEM** tab and assign **RigidSection** to the Rigid Section parameter.

![FEM Tab](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-124755.png?api=v2)

{% hint style="info" %}
OpenBrIM automatically uses the **RigidSection** defined in Properties for rigid connections.
{% endhint %}

## Verification

{% hint style="success" %}
The completed pier caps are shown below.
{% endhint %}

![Completed Pier Cap Plan](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-130242.png?api=v2)

![Completed Pier Cap 3D](https://openbrim.atlassian.net/wiki/download/attachments/2258665498/image-20230831-130308.png?api=v2)


---

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