tension members only design

[abla1984]

Hi all
I designed concrete building,then I removed column,so I added x steel bracing (rolled section) as tension members only in sap2000 to redistribute the forces,the problem that the sap2000 designed it but i don't have handy way to design it ,I hope if any one had a way how to design these tension members only and what is there strength and diameter , I'll be thankful
I've attached a snapshot of frame from building where i add x bracing so that you can see what I mean

 

[ishvaaag]

You resource to frame analysis to get forces that are not derivable isostatically. For the right set of X crosses you can't usually derive proper design strengths without accounting for the corresponding deformations to the hypotheses. You can do something, however for your top left X bracing set, in that you can derive just from geometry and loading a worst hypothesis with which to design the brace that comes in tension, then upon the connections and selected design of the tension brace see how to deal with the brace that would take compression if not avoided.