Question: What exactly are the cross-frame library's vertical and horizontal left and right offsets?

Answer: The cross-frame library's vertical and horizontal left and right offsets indicate the eccentricity distance from the reference axis in the structural element Top, Bottom, or diagonal Left or Right.

In OpenBridge Modeler, at the Utilities main top menu, at the Library tab, in the Cross Frames button, for each cross-frame configuration saved, there is the possibility of specifying the plate parameters used for each member or connection plate on the Connection Plates tab. The parameters include: 

• Template name.
• Members / Connection Plates:
  • Template
  • (Optional) Horizontal and Vertical Offsets, Axial Offsets, and Left and Right Offsets, as needed.

These optional offsets are defined as the eccentricity distance from the reference line to the element start and end in the Top Structure, Left and Right diagonal, and bottom Structure.

• Horizontal Offset: Horizontal Offset from the element (dashed) centerline reference
• Vertical Offset: Vertical Offset from the element (dashed) centerline reference
• Left Offset: Left Offset from the element (dashed) centerline reference
• Right Offset: Right Offset from the element (dashed) centerline reference
• Axial Offset: Horizontal Offset from the element (dashed) centerline reference

Note that the Centerline Reference, the element dashed line, can be measured from:

• Top
• Middle
• Bottom
• Center of Gravity

Tips: 

• The plate types are arranged in a general formation of how they are arranged in a physical cross-frame.
• For X Frames, you can choose to orient the Center Connection Plate along the left or right diagonal member. 
• To change the cross-frame bay dimensions in the display window, Click display options, Type height and width to use the cross-frame bay