Leaderboard

That is the intention

yes, in this case most of lateral load carrying by shear wall, so your beam column have lesser lateral forces, thats why the reinforcement has decreased in these members

Additional suggestions which may resolve negative-stiffness errors include: Remove auto line constraints. Select all deck/shell objects in the model, then select Assign > Shell Elements > Auto Line Constraint and uncheck the Apply to Full Structure option. This will remove auto line constraints and possibly resolve instabilities. Dear Umar, The above suggestion works! thank you. However, I would love to understand the engineering behind it. How line constraint is affecting the stability of the floors in P-Delta analysis when the slab stiffness modifier is reduced from 1.0 to 0.5 for instance? Do you have some sort of technical explanation to that? Best regards, Wael

In this connection, you might like to have a look on this link that contains a very useful discussion on use of cracked sections in the stiffness analysis of reinforced concrete members. Regards.