Tub Girder

This section defines the steel tub girder geometry with station-dependent plate dimensions.

Navigation: Superstructure > Steel Girders > Tub Girder

For detailed parameter explanations, see the Tub Girder Reference.

Steps

Step 1: Navigate to Tub Girder

Navigate to Steel Girders > Tub Girder in the tree view.

Tub Girder navigation

Step 2: Assign Girder Layouts

Click the three-dot icon on the Girder Layout cell and set GL1 and GL2.

Step 3: Define Top Flange Width

Click the three-dot icon on the top flange width cell, select Edit, and enter 22 for both GL1 and GL2.

Top flange width

Step 4: Define Station-Dependent Thicknesses

Click the three-dot icon on the top flange thickness cell and select Edit (Spreadsheet) to enter station-dependent values.

Edit spreadsheet

Thickness data

Step 5: Set Web Depth

Enter 78 for Web Depth Projected to CL of box.

Web depth

Step 6: Define All Plate Dimensions

Use Edit or Edit (Spreadsheet) to define:

• Top flange thickness
• Web depth and thickness
• Bottom flange width and thickness
• Haunch thickness and additional haunch width

Plate dimensions

Step 7: Assign Materials

Click the three-dot icon on material cells and select A709_50W for:

• Top Flange Material
• Web Material
• Bottom Flange Material

Material assignment

Step 8: Configure FEA Settings

Navigate to FEA Setting tab and assign RigidSection to the Rigid Section column.

FEA settings

Rigid section

Quick Tip: Haunch Thickness Definition

Haunch Thickness = Distance from the bottom of the deck to the bottom of the top flange.

Haunch definition

Quick Tip: FE Model Generation

OpenBrIM automatically generates the FE model based on parametric relationships. Flanges use FeLine elements and webs use FeSurface elements.

Verification

The completed tub girder model is shown below.

Completed girder 3D

Completed girder cross-section