> 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.md).

# Pier

This section defines pier structures including pier caps and columns.

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

Pier structures include:

* **Pier Cap:** Horizontal beam supporting girders
* **Pier Column:** Vertical columns supporting pier caps

## Sections

| Section                                                                                                                                     | Description                             |
| ------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------- |
| [Pier Cap](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/substructure-ex1-cug/pier-ex1-cug/pier-cap-ex1-cug.md)       | Define pier cap geometry and properties |
| [Pier Column](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/substructure-ex1-cug/pier-ex1-cug/pier-column-ex1-cug.md) | Configure column sections and locations |

{% hint style="success" %}
Complete pier cap definitions before configuring pier columns, as columns reference pier caps.
{% endhint %}


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