place Steel Cross Frames for Concrete Girder Bridges

To place cross frames on a concrete girder superstructure, use the following procedure. You must have concrete superstructure with a beam group already placed. You must use an existing cross frame template and an existing Connector Angle template. Only one cross frame group can be added to a beam layout.

Note: When working with cross frames and stiffeners, it is helpful to turn off the display of the deck. You can quickly do this by clearing the selection on the Decks entry for the current bridge unit on the Bridge Model tab of the Project Explorer.

Either:

On the Home ribbon tab, select the Place Cross Frames tool in the Superstructure group.

or

Key in: BMGEOM CROSSFRAME PLACECROSSFRAMES
Select the beam group:
1. Data point on the beam group to select it.
2. Data point again elsewhere to confirm the selection.
The Cross-Frame Placement dialog opens.

(Optional) To place a series of cross frames between two beams:

Select the names of two adjacent beams in the left-hand list. "Bays" in OpenBridge Modeler are referred to by the names of the beams along each side.
Click Wizard. The Cross-Frame Location Wizard dialog opens.

Specify the number of cross-frames by either:

Option

Description

Number of Locations

Select this option and type the number of cross frame locations along the selected beams.

Spacing

Either

enter a nominal spacing between cross frames along selected beams

Enter Number@spacing (can be multiple sets such as 2@L1 3@L2)

Use option to appl y cross frames only in Current Bay or apply to All Bays
Type the Start Station Offset to the first cross frame and End Station Offset to the last cross frame
Select Position Lock option.
- None
  - left and right locations are specified individually.
- Normal to Left Beam
  - the cross frame is placed normal to the left beam. The location on the right beam is calculated by the program.
- Normal to Right Beam
  - the cross frame is placed normal to the right beam. The location on the left beam is calculated by the program.
- Link Left-Right
  - the same value is used for both beams, regardless of curvature or skew.
Select the Orientation to align the cross frames upstation or downstation of the supporting connectors. It is important to coordinate this selection with the member alignment in the selected stiffener template.
Select the Connector from the drop down list from library.
Input the left, right heights and offsets as shown in the figure below to describe how the cross frames fits between the concrete girders.
Selecting the Level option will allow the cross frame to be placed horizontally/level, and will grey out options for right height and right offset.
Select the Cross-Frame template to use.
Click Generate. The cross frames are added to the beam. The dialog remains open to allow you to quickly generate additional stiffeners on the same beam bay.
Click Close when finished.

(Optional) To copy cross frames to another beam bay:
1. Select the beam bay and cross frames on that beam that you want to copy to another beam bay.
2. Click Copy. The Bay Copy dialog opens.
3. Select the supportline groups or beam bays to which you want to copy cross frames.
4. Click Copy By Ratio.
The cross frames are copied to the selected beam bays.
(Optional) To add an individual cross frame: This method allows you to add a cross-frame in reference to one of several points along the beam, including existing cross-frames.
1. Select the names of two adjacent beams in the left-hand list. "Bays" in OpenBridge Modeler are referred to by the names of the beams along each side.
2. Click Wizard. The Cross-Frame Location Wizard dialog opens.
3. Select the Ony-By-One tab.
4. Select the reference type in the From drop-down list and then type a Distance with respect to this location.
5. Select Position Lock option.
  - None
    - left and right locations are specified individually.
  - Normal to Left Beam
    - the cross frame is placed normal to the left beam. The location on the right beam is calculated by the program.
  - Normal to Right Beam
    - the cross frame is placed normal to the right beam. The location on the left beam is calculated by the program.
  - Link Left-Right
    - the same value is used for both beams, regardless of curvature or skew.
6. Select the Orientation to align the cross frames upstation or downstation of the supporting stiffeners. It is important to coordinate this selection with the member alignment in the selected stiffener template.
7. Select the Connector templates.
8. Select the Cross-Frame template to use.
9. Click Generate. The cross frames are added to the beam. The dialog remains open to allow you to quickly generate additional stiffeners on the same beam bay.
10. Click Close when finished.
(Optional) To add an individual Cross Frame (alternate method): This method allows you to quickly add a cross-frame at a set distance from the start of the beam group.
1. Select the beam bay name in the left-hand list.
2. Click Add. A new row is added at the end of the list of cross frames.
3. Select the Position Lock and then type the Left Location and Right Location distances per the selection.
4. Select the Cross-Frame template to use.
5. Select the Orientation to align the cross frames upstation or downstation of the supporting stiffeners.
6. Select the Left Stiffener and Right Stiffener templates.
Click Validate. You are notified of any detected layout errors.
Click Close. The model is updated with the cross frames.
You can add cross frame placement, cross frame, angle connector definitions, and connection plate definitions to the Input echo report.

Cross frame quantity estimates are automatically added to the Quantities report. You can also set the Detailed Cross-Frames option to include line item quantities for cross-frame components.

Connector Angle definitions