# Generative Objects ## Open the Steel I-Girder Workflow 1. Log in to your account and locate **Project** in the top-right corner. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20230703-094719.png?api=v2) 2. Click **Project**, then click **NEW** in the top-left corner. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20230703-094913.png?api=v2) 3. Under **Steel Bridge Workflows**, find **Steel I-Girder Bridge Workflow** and click **New Project**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-160229.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-142439.png?api=v2) 4. Provide a name for your project and open the example. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20230711-113559.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20230705-110649.png?api=v2) {% hint style="warning" %} The initial download of the library components **takes approximately 2 minutes 30 seconds**. Subsequent openings of the same project are noticeably faster because OpenBrIM library objects are cached in your browser; loading then **takes less than 2–3 seconds**. {% endhint %} ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-160337.png?api=v2) ## Create the Superstructure with a Generative Library Object 1. Click an empty area in the graphics window, then click the magic icon. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-160751.png?api=v2) 2. Choose **Generative: Modeling**, then **Steel I Girder Bridge Layout**. A warning appears because superstructure generation requires at least one alignment. Switch back to the spreadsheet to create one. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-160853.png?api=v2) 3. Click **DATA** in the bottom-middle of the screen to open the spreadsheet. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161156.png?api=v2) 4. Set **Start Station** to **0**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231002-114147.png?api=v2) 5. Click the three-dot menu in the **Start Station** cell, then click **Editor** to define alignment properties. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20230824-113528.png?api=v2) 6. Click the **+** icon next to **Horizontal** and add a circular segment. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20221004-004318.png?api=v2) 7. Set **Length** = **530 ft**, **Radius** = **700 ft**, **Direction** = **Towards Right**, then click **Accept**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20221004-004324.png?api=v2) 8. Click **Accept**, then click **Zoom Extent** to view the alignment in the graphics window. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20221111-142319.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161610.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161625.png?api=v2) 9. Click an empty area in the graphics window, click the magic icon, choose **Generative: Modeling**, then **Steel I Girder Bridge Layout** again. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161840.png?api=v2) 10. Set **Bridge Start Station** = **0 ft** and **Bridge Length** = **530 ft**, then click **Generate**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-162308.png?api=v2) 11. Open the **Support Lines** spreadsheet and set the support stations to **0, 160, 370, 530**. After generation, you can keep customizing — for example, open the **Plate Girder** spreadsheet to enter plate dimensions. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-162701.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-162728.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-162903.png?api=v2) ## Create the Substructure with Generative Library Objects 1. Click an empty area in the graphics window, click the magic icon, choose **Generative: Modeling**, then **Hammerhead Pier**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-163442.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-163411.png?api=v2) 2. Open the **Pier Cap** section in the workflow tree and adjust the rebar data. See the screenshots for step-by-step guidance. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-163657.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-163710.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-163720.png?api=v2) 3. Click an empty area in the graphics window, click the magic icon, choose **Generative: Modeling > Straddle Bent**, then set **Support Line** to **SL2**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-164018.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-164034.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-164210.png?api=v2) 4. Return to **Boundary Conditions** and set the bearing fixities and **Transfer Forces to Substructure** parameter. Because both Support Line 1 and Support Line 2 now have substructures, **Transfer Forces to Substructure** should be **Yes** for both locations. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-164417.png?api=v2) ## Create Stages with Generative Library Objects 1. Click an empty area in the graphics window, click the magic icon, choose **Generative: FEA**, then **Steel I Girder Staged Construction and Loading**. Adjust the loads as needed and click **Generate**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-164633.png?api=v2) 2. Review the FEA stages and loads that have been generated. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/Screenshare%20-%202023-10-26%2012_59_37%20PM.mp4?api=v2) ## Add Code-Check Objects for the Superstructure and Substructure 1. Click an empty area in the graphics window, click the magic icon, choose **Generative: Design > Steel I Girder Code Check**. Select the girder and click **Generate** — 10 code-check stations are created per span along the girder. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-171938.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-172252.png?api=v2) 2. Click an empty area in the graphics window, click the magic icon, choose **Generative: Design > Steel I Girder Substructure Code Check**. This creates a code-check object for the pier at the top and bottom of the pier column. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-161714.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-172144.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-172333.png?api=v2) {% hint style="warning" %} Analysis for this project typically **takes around 2.5 minutes**, and the design run **takes around 10 minutes**. {% endhint %} 3. Run **Analysis** and **Design**. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-172619.png?api=v2) ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-172912.png?api=v2) {% hint style="success" %} Generation is complete. You can now view the design reports. {% endhint %} ## AI-Powered Generative Modeling (Roadmap) OpenBrIM is being trained with machine-learning algorithms to optimize input parameters for generative bridge components automatically, taking project-specific site constraints into account. This capability is in active development. ![](https://openbrim.atlassian.net/wiki/download/attachments/2294284294/image-20231026-173707.png?api=v2) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.openbrim.org/quick-guides/generative-objects.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. 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