Parametric Bridge Engineering

Access an Example Steel Bridge Model

Please follow the instructions below to access the 'Steel I-Girder Training Example' model provided as an example:

Instructions	Screenshot
Log in to your account and locate the 'Project' option in the top right corner.
Click on 'Project' and then select 'NEW' from the top left corner of the screen.
Under the 'Example Project' section, click on 'New Project' specifically located within the 'Steel I-Girder Training Example'.
Provide a name for your project and proceed to open the example project.

Please note that the initial download process for the library components takes approximately 2 minutes and 30 seconds to complete. The reopening of the same project will experience a notable increase in speed, primarily due to the caching of OpenBrIM library objects within your browser. The loading of library objects during this process generally takes less than 2-3 seconds.

---

OpenBrIM Parametric Modeling

This section will showcase the practical application of the OpenBrIM Platform's cloud-based parametric approaches, emphasizing their ability to enhance the user's modeling experience.

In the following instructions, we will modify the web depth parameter through the spreadsheet, and both the 3D model and FEA model will be updated accordingly. Please refer to the following instructions for guidance.

Instructions	Screenshot
Click on the 'DATA' button located in the bottom-middle section of the screen. This will open a spreadsheet.

• To adjust the height of the spreadsheet, click and hold the 'DATA' button with the left mouse button, then drag it to the desired position.

• To close the spreadsheet, simply click once on the 'DATA' button.

Instructions	Screenshot
Click on 'Plate Girder' under the 'Superstructure' section in the workflow tree. This action will display all the project girders and their corresponding parameters in the spreadsheet.
Let's take a look at how the Finite Element model looks with the current web depth before changing it. Click on the icon in the top left corner to open the sliding menu. In the menu, you will see MODEL, FEA, CAD, DOCS, SUPPORT, and USER SETTINGS. To activate the Finite Element model, click on FEA.

You can zoom in and out by using the scroll wheel of your mouse. To move around, press and hold the scroll wheel while moving your mouse. If the bridge is out of view, you can realign the bridge by clicking on the ":align_1:" button located in the top right corner of the screen. Once you click on an object, pressing ":align_1:" will allow you to rotate around that object. To rotate an object, hold down the left mouse button and drag it.

Instructions	Screenshot
The Finite Element model appears as shown on the side with the current web depth (84 inches). To modify the web depth parameter of the 'G4' girder, click on the corresponding 'Web Depth' cell of the girder in the spreadsheet. Next, enter the value of 55 inches as the web depth in the cell.

Updating the dimensional change in the 3D model and Finite Element model will take approximately 10 seconds. When a user makes changes to a parameter in the spreadsheet, the 3D Model/FEA Model, CAD drawings, and dynamic reports such as quantity reports are automatically updated to reflect the impact of the new parameter. OpenBrIM triggers a compilation process using your inputs to generate these updated outputs.

Instructions	Screenshot
The new Finite Element model appears as shown on the side with the updated web depth.
Open the sliding menu again by clicking on the icon in the top left corner, and then click on 'MODEL' to switch to the 3D view.
You can see the changes in both the 3D view and the Finite Element model in the visual on the side.

For a detailed explanation of how to input girder plate dimensions for your project, please refer to the following page: Plate Girder [SIG]

Alternatively, you can view the process in action by referring to our training example page: Plate Girder [EX1-SIG]

---

OpenBrIM Spreadsheets: Excel-Like Functionality with Parametric Dependencies

This section will showcase the practical application of the OpenBrIM Platform's cloud-based parametric excel-like functionality, highlighting its ability to enhance the user's modeling experience.

Cross-frame skew, roadway skew, and support line skew all utilize the same inputs, but users are required to input these values at three distinct locations. We will enable OpenBrIM's spreadsheet to function similarly to Excel, allowing cells to reference one another, and you can follow the instructions below to implement this on your end.

Instructions	Screenshot
Click on 'Support Line' under 'Bridge Geometry' in the workflow to access the skew angle parameter.
To change the skew angle of 'Abut1', click on the corresponding cell (marked in red).
When the skew angle value of 'Abut1' is set to zero, it will appear as shown on the right-hand side.
When the skew angle of 'Abut1' is set to '-15' degrees, it will appear as shown on the right-hand side.

As observed, the cross-frames are not aligned with the support line.

To parametrically align the skew angle of the cross-frame with the skew angle of the support line, you can follow these steps:

1. Copy the skew angle value of the support line using the "Copy Parameter" function.

2. Paste this parametric expression into the skew angle value of the cross-frame.

3. By doing so, the skew angle of the cross-frame will be dynamically linked to the skew angle of the support line.

Instructions	Screenshot
Click on the skew angle cell of 'Abut1'. When you click on the cell, you will see three-dots appear to the right of the cell. Then, click on the three-dots that appear on the right side of the cell. From the options provided, select 'Copy Parameter'. Now, the skew angle parameter (not the value) has been copied.

The parameter copied: =Abut1.s_skew

Instructions	Screenshot
Expand the 'Cross Frames' section under 'Superstructure' in the workflow. Then, click on 'Cross-frame K Top' to access its parameters.
After clicking on the skew angle cell of 'CFTK1', you will see three dots appear to the right of the cell. Click on the three dots to access additional options and select 'Paste' from the menu.

After clicking on the cell, you can also paste the copied parameter by using the keyboard shortcut CTRL+V.

Instructions	Screenshot
Perform the paste operation for 'CFKT28' and 'CFKT29' in the same manner as before. As observed, the skew angles of the cross-frames have now been aligned with the support line.
You no longer need to manually adjust the skew angles of the cross-frames whenever the skew angle of the support line changes. The skew angle values of the cross-frames are now parametrically linked to the skew angle value of the support line.

Cross-frame skew now provides a reference similar to how one cell in Excel refers to another cell, using the support line's skew value. Our environment accommodates operations, functions, and logical operators, enabling you to input more complex equations into these cells. For further details, please consult our ParamML documentation: Mathematical Functions

---

Aligning Roadway with Skew Angle

Additionally, to align the roadway with the skew angle, please follow the instructions below:

Instructions	Screenshot
To align the roadway with the skew angle of the support line, expand the 'Superstructure Attachments' section in the workflow and click on 'Roadway' to access the parameters related to the roadway alignment. Then, click on 'Edit' from the three-dot menu on the right side of the 'Roadway Dimensions' cell. Paste the skew angle copied from 'Abut1' into the 'Skew' parameter at zero station.