Hello All,
This has been brought up many times in my mind. When we are analyzing multi story buildings (15,20,30 etc.) in E-tabs, we are supposed to check Modal Mass Participation factor in order to see if Torsion governs first two modes or not. Do we have to check this while keeping P-Delta "ON" or "Off"? In my opinion this check of Modal Mass Participation is Serviceability check, whereas P-delta is simply a design consideration.
Additionally, does the code say anywhere, what sort of P-Delta analysis has to be carried out? In E-tabs there are two options, Non - Iterative or Iterative. If we do Iterative analysis, where does the code specify factors for each defined load case (DL,LL,EQ)?
This has been brought up many times in my mind. When we are analyzing multi story buildings (15,20,30 etc.) in E-tabs, we are supposed to check Modal Mass Participation factor in order to see if Torsion governs first two modes or not. Do we have to check this while keeping P-Delta "ON" or "Off"? In my opinion this check of Modal Mass Participation is Serviceability check, whereas P-delta is simply a design consideration.
Additionally, does the code say anywhere, what sort of P-Delta analysis has to be carried out? In E-tabs there are two options, Non - Iterative or Iterative. If we do Iterative analysis, where does the code specify factors for each defined load case (DL,LL,EQ)?