> 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/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg.md).

# Superstructure

This section defines all superstructure components for the Steel Tub Girder Bridge including girders, deck, bracing, and connections.

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**Navigation:** Superstructure
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## Overview

The superstructure consists of:

* **Steel Girders:** Tub (box) girders with variable plate thicknesses
* **Deck:** Composite concrete deck with cross-sections
* **Bracing:** Internal and external cross-frames, lateral bracing, diaphragms
* **Connections:** Bolted field splices, shear studs, bolt properties
* **Boundary Conditions:** Bearing fixity at support locations

## Sections

| Section                                                                                                                                              | Description                                        |
| ---------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------- |
| [Steel Girders](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg/steel-girders-ex1-stg.md)             | Define tub girder geometry and materials           |
| [Deck](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg/deck-ex1-stg.md)                               | Configure deck cross-sections and concrete deck    |
| [Bracing](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg/bracing-ex1-stg.md)                         | Internal/external cross-frames and lateral bracing |
| [Connections](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg/connections-ex1-stg.md)                 | Field splices, shear studs, and bolt properties    |
| [Boundary Conditions](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg/boundary-conditions-ex1-stg.md) | Bearing fixity at supports                         |

{% hint style="success" %}
Complete Superstructure definition before configuring Construction staging.
{% endhint %}


---

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