Portal Brace / Wind Bent in PEB building

Question

Hi All, 
 I have a requirement to avoid cross bracing and introduce Portal Brace / Wind Bent (Red Colour) in PEB building. The Red columns flanges are stitch bolted/welded to the webs of the rigid frame columns (tapered) and extend down to 150 mm above F.F.L. Please advise the best way to model this in Staad and any other points to consider. A sample model for reference would be highly appreciated.

Sye · Answer

You may create the columns of the portal brace using the existing nodes for the frame columns and use member offsets to locate those portal frame columns at an offset. A sample model is attached 
 0677.Structure1.STD

Sye · Answer

In that case the bottom of the portal would be a separate node at a distance of 2' from the one that is at the base of the frame column. The portal column would be modeled as a single member as opposed to being split, as in the previous case. The top node of the portal column would be a node in the frame column at the same level. So initially when you define the portal column it would be inclined. Then you would apply an offset of 2 ft laterally at the top of the portal column which would make it straight.