> 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/combinations-ex1-stg.md).

# Combinations

This section defines load combinations and result extraction for the Steel Tub Girder Bridge analysis.

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**Navigation:** Combinations
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## Overview

Load combinations are used to determine critical design scenarios by combining various loads with appropriate load factors according to AASHTO specifications.

## Sections

| Section                                                                                                                                                      | Description                                        |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------------------------------------------- |
| [Result Extraction Cases](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/combinations-ex1-stg/result-extraction-cases-ex1-stg.md)   | Define result extraction for analysis output       |
| [Design Load Combinations](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/combinations-ex1-stg/design-load-combinations-ex1-stg.md) | Configure limit states and load combination tables |

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Complete Combinations before performing code checks.
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