Estudo sobre parâmetros para cálculo da estabilidade global de estruturas de edificações

Abstract

Modernity and technological advances have brought with them the need for increasingly slender buildings. In this way, studies around structural stability become increasingly more important, contributing directly to the improvement of structural projects, and consequently to the civil construction market and its needs. The Brazilian standards ABNT NBR 6118 and ABNT NBR 8800, respectively applied to projects of concrete and steel structures, indicate some methods for non-linear analysis for structures, such as the application of parameters such as the coefficients α and γz, or the Effort Amplification Method. The non-linear structural analysis allows a closer approximation with reality when dealing with the structural behavior of buildings. It is known that, for a set of horizontal and vertical loads applied to a building structure, different values can be found for internal efforts and displacements depending on the methodology adopted for the consideration of non-linear effects, which can be approximated or obtained by more rigorous calculation methods. In this work, a study was conducted in typical models of structures with multiple floors, where the geometric non-linear behavior of buildings was evaluated in relation to stability and the variations of stability parameters in face of the increase in the number of floors and the variation in the amount of structure spans. With these parameters, structures are classified into mobile or fixed nodes, thus defining whether non-linear effects should be considered in the structural design. In general, it is observed that the consideration of such effects can result in more economical and safer structures from a structural point of view.