Considerations about the determination of γz coefficient

In this work, the γz coefficient, used to evaluate final second order effects in reinforced concrete structures, is studied. At the start, the influence of the structural model in determination of γz coefficient is evaluated. Next, a comparative analysis of γz and B2 coefficient, usually employed to evaluate second order effects in steel structures, is performed. In order to develop the study, several reinforced concrete buildings of medium height are analysed using ANSYS-9.0 [1] software. The results show that simplified analysis provide more conservative values of γz. It means that, for structures analysed by simplified models, large values of γz don't imply, necessarily, in significant second order effects. Furthermore, it was checked that γz can be determinated from B2 coefficients of each storey of the structures and that, for all the analysed buildings, the average values of the B2 coefficients are similar to γz.