Análise não linear geométrica e física global/local de pilares de edifícios em concreto armado

Abstract

In this thesis, aspects inherent to the nonlinear physical and geometric analysis of columns of bracing structures for buildings in reinforced concrete will be addressed. The paper focused on the structural analysis of the columns through the use of a computational tool capable of performing rigorous non-linear analysis, studying conventional models using the finite element method. The inertia reductions in the columns are evaluated, as well as the effects of nonlinearities in global and local analysis in an integrated way in a single model. The models were previous designed to present reinforcement rates lower than the maximum allowed by ABNT NBR 6118:2014. Models with three different relationships between columns sides and three concrete strength classes were analyzed. The results showed that the stiffness of beams and columns for global modeling is close to those proposed by ABNT NBR 6118:2014 for concrete C25 and indicates that they are lower for higher concrete classes, in addition to indicating that the relative stiffness beam/column is lower than 0.5 as given by the aforementioned standard. Local second-order effects were very small, even for the most displaceable models.