> 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.md).

# Curved Steel Tub Girder Bridge

This example demonstrates how to model, analyze, and design a Steel Tub Girder Bridge using OpenBrIM.App.

{% hint style="success" %}
**Ready to start?** Access the completed example in **New Project > Example Projects**, or follow this step-by-step guide to build from scratch.
{% endhint %}

![Steel Tub Girder Bridge Model](https://openbrim.atlassian.net/wiki/download/attachments/2101903444/ws-guide-steeltubgirder-20230703-121430.png?api=v2)

## Workflow Steps

| Step | Section                                                                                                                                     | Description                                    |
| ---- | ------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------- |
| 1    | [Modeling on OpenBrIM.App](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/modeling-on-openbrimapp-ex1-stg.md)      | Create new project                             |
| 2    | [Bridge Geometry](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/bridge-geometry-ex1-stg.md)                       | Define alignment, supports, girder layout      |
| 3    | [Properties](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/properties-ex1-stg.md)                                 | Configure materials, rebars, sections          |
| 4    | [Superstructure](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-ex1-stg.md)                         | Define tub girders, deck, bracing, connections |
| 5    | [Substructure](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/substructure-ex1-stg.md)                             | Configure piers and foundations                |
| 6    | [Construction](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/construction-ex1-stg.md)                             | Set up staged construction sequence            |
| 7    | [Loading](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/loading-ex1-stg.md)                                       | Apply live, wind, temperature loads            |
| 8    | [Superstructure Attachments](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-attachments-ex1-stg.md) | Add barriers and roadway                       |
| 9    | [Combinations](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/combinations-ex1-stg.md)                             | Configure load combinations                    |
| 10   | [Templates for Code Check](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/templates-for-code-check-ex1-stg.md)     | Set up design verification templates           |
| 11   | [Superstructure Code Checks](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/superstructure-code-checks-ex1-stg.md) | Verify girder and bracing design               |
| 12   | [Substructure Code Checks](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/substructure-code-checks-ex1-stg.md)     | Verify pier and foundation design              |
| 13   | [Reports](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/reports-ex1-stg.md)                                       | Generate camber diagrams and quantities        |
| 14   | [Analyze and Design](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/analyze-and-design-ex1-stg.md)                 | Run analysis and design checks                 |

## Key Capabilities

**3D Modeling & Export**

* Generate parametric 3D models with substructure and superstructure
* Export to DGN/DXF/IFC formats

**Finite Element Analysis**

* Time-dependent staged construction analysis
* Influence surface-based live load analysis
* Composite/non-composite girder states

**Loads**

* Wind loads on structure and live load per AASHTO
* HL-93, legal trucks, permit trucks
* Temperature and surface loads

**Design & Load Rating**

* AASHTO 9th Edition code checks
* Steel tub girder, splices, cross frames, shear studs
* Pier caps, columns, footings, piles
* Load rating per Manual for Bridge Evaluation

**Reports**

* Camber diagrams
* Quantity takeoffs
* Seat and slab elevation tables

![Example project access](https://openbrim.atlassian.net/wiki/download/attachments/2101903444/image-20230710-161532.png?api=v2)

![Project selection](https://openbrim.atlassian.net/wiki/download/attachments/2101903444/image-20230710-161550.png?api=v2)


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