> 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/superstructure-ex1-cug/diaphragm-ex1-cug.md).

# Diaphragm

This section defines diaphragm elements that provide lateral stability and load distribution for the U-girders.

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**Navigation:** Superstructure > Diaphragm
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## Overview

Two types of diaphragms are used in this bridge:

* **Internal Diaphragm:** Located within each U-girder at bearing locations
* **External Diaphragm:** Located between U-girders to ensure composite action

## Sections

| Section                                                                                                                                                          | Description                              |
| ---------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------- |
| [Internal Diaphragm](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/superstructure-ex1-cug/diaphragm-ex1-cug/internal-diaphragm-ex1-cug.md) | Diaphragms within U-girder sections      |
| [External Diaphragm](/examples/concrete-bridge-examples/example-concrete-u-girder-bridge/superstructure-ex1-cug/diaphragm-ex1-cug/external-diaphragm-ex1-cug.md) | Diaphragms connecting adjacent U-girders |

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Complete both diaphragm types to ensure proper structural behavior of the superstructure.
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