> 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/properties-ex1-stg.md).

# Properties

This section defines materials, rebars, and sections used throughout the Steel Tub Girder Bridge model.

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**Navigation:** Properties
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## Overview

Properties establish the material and geometric characteristics for all bridge components:

* **Materials:** Concrete, structural steel, and reinforcing steel properties
* **Rebars:** ASTM rebar profiles for reinforcement
* **Sections:** Cross-sectional shapes for substructure components

## Sections

| Section                                                                                                                      | Description                                     |
| ---------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------- |
| [Materials](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/properties-ex1-stg/materials-ex1-stg.md) | Import and configure material properties        |
| [Rebars](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/properties-ex1-stg/rebars-ex1-stg.md)       | Import ASTM rebar profiles                      |
| [Sections](/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/properties-ex1-stg/sections-ex1-stg.md)   | Define substructure sections with reinforcement |

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Complete Properties before defining Superstructure and Substructure components.
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---

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