Superstructure Components

Under this section, we’ll model girders, cross-frames, deck, connection components, barriers, and roadway in 3D. Since the parametric relationship between 3D objects and the FE representation of each object is already defined, the finite element model will be automatically generated by OpenBrIM.

Girder Support Conditions

	Follow the below steps to set boundary conditions for each bearing location (insertion point) that you have defined while creating the bridge layout.
1	Go to Bearing Fixity on the tree view next to data spreadsheet.
2	Set Tx/Ty/Tz/Rx/Ry/Rz.
3	Set Transfer Force to Substructure as Yes for interior pier locations.
4	Set Transfer Force to Substructure as No for start and end support locations.
5	Quick Tip FE behavior of Transfer Force to Substructure

Girders

Follow the below steps to create girders.

1

Go to Plate Girder on the tree view next to data spreadsheet.

2

Click three-dots icon on Girder Layout cell and set a layout.

Edit the plate girder dimensions. To enter a station-dependent dimension;

	Follow the below steps to edit the plate girder dimensions.
1	Click three-dots icon on the cell and Edit (spreadsheet).
2	Define the station-dimension relationship on the spreadsheet.
3	Top Flange thickness, web depth and thickness, bottom flange width and thickness, haunch thickness, and additional haunch width parameters can be defined similarly to top flange width.
4	Click three-dots icon on top flange & web & bottom flange material cells and import a Material.
5	You can edit the FE mesh settings of girders from FEA Settings tab.
6	The girder FE model will be automatically generated by the OpenBrIM based on the parametric relation between the 3D and FEM in the library component. The girder section is represented using FeLine elements for flanges and FeSurface elements for the web.
7	Quick Tips 3D view of girders: FEM view of girders:

Cross-Frames

Add K Top type cross frames to start and end support locations and add X type cross frames based on the spacing data.

	Follow the below steps to create cross frames.
1	Pick 2 Girders that the cross frame will be placed between.
2	Enter the Station of the cross frame.
3	Go to Sections tab.
4	Import AISCL8X8X3/4 and assign it to Top & Bottom & Diagonal Chord Sections.
5	Go to Gusset Plate tab and edit the gusset plate offset values for top, bottom and diagonal plates.
6	Go to Stiffener tab
7	Edit the vertical stiffener thickness as 0.75 and vertical stiffener width as 7 in.
8	Go to Geometry tab.
9	Edit the offset values for top chord, diagonals, and bottom chord.
10	Perform the same steps for X type cross-frames.
11	Quick Tip The 3D plan view after entering the cross-frames: The FE plan view after entering the cross-frames:

Deck

You need to define at least 2 deck cross-sections along the deck.

	Follow the below steps to edit the plate girder dimensions.
1	Click three-dots icon on the cell and Edit (spreadsheet).
2	Define the station-dimension relationship on the spreadsheet.
3	Top Flange thickness, web depth and thickness, bottom flange width and thickness, haunch thickness, and additional haunch width parameters can be defined similarly to top flange width.
4	Click three-dots icon on top flange & web & bottom flange material cells and import a Material.
5	You can edit the FE mesh settings of girders from FEA Settings tab.
6	The girder FE model will be automatically generated by the OpenBrIM based on the parametric relation between the 3D and FEM in the library component. The girder section is represented using FeLine elements for flanges and FeSurface elements for the web.
7	Quick Tips 3D view of girders: FEM view of girders: