> 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/bridge-geometry-ex1-cug.md).

# Bridge Geometry

This section defines the geometric layout of the Concrete U Girder Bridge, including alignments, support locations, and girder configurations.

{% hint style="info" %}
**Navigation:** Bridge Geometry
{% endhint %}

## Overview

Bridge Geometry establishes the foundational layout for the entire bridge model. This includes:

* **Roadway Alignment:** Horizontal and vertical alignment with cross-sections
* **Bridge Alignment:** Assignment of alignments to bridge structures
* **Support Lines:** Locations of abutments, piers, and temporary supports
* **Insertion Points:** Positioning of U-girders along support lines
* **Girder Layout:** Connection of insertion points to form girder lines

## Sections

| Section                                                                                                                                       | Description                                                               |
| --------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------- |
| [Roadway Alignment](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/bridge-geometry-ex1-cug/roadway-alignment-ex1-cug.md) | Define horizontal, vertical, and transverse alignment                     |
| [Bridge Alignment](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/bridge-geometry-ex1-cug/bridge-alignment-ex1-cug.md)   | Assign roadway alignment to bridges                                       |
| [Support Lines](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/bridge-geometry-ex1-cug/support-lines-ex1-cug.md)         | Define support line stations for abutments, piers, and temporary supports |
| [Insertion Point](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/bridge-geometry-ex1-cug/insertion-point-ex1-cug.md)     | Position U-girders along support lines                                    |
| [Girder Layout](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/bridge-geometry-ex1-cug/girder-layout-ex1-cug.md)         | Connect insertion points to create girder lines                           |

{% hint style="success" %}
Complete each section in order to establish the bridge geometry before proceeding to Properties.
{% endhint %}


---

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