Estudo comparativo : dimensionamento de barras comprimidas em perfis H soldados utilizando a ABNT NBR 8800:2008 e a proposta de revisão

Abstract

Currently, the Brazilian code for the design of steel and composite structures for buildings, ABNT NBR 8800:2008, is under revision. Therefore, this paper begins with a historical account of steel in civil construction and a summary of the review documents of the Brazilian standard. Then, ABNT NBR 8800:2008 and PR NBR 8800:2022 are compared in order to identify the changes that influence the design of steel structural elements. It is clear that significant modifications occur for members subjected to an axial compressive load, and the new equations are applicable, without distinction, for doubly symmetric wide-flange sections that are rolled or welded. The main changes proposed by PR NBR 8800:2022 are identified and the information is highlighted following the order of the contents of the review document. From these data, spreadsheets are created to calculate the design compressive strength of doubly symmetric welded sections. After this step, cross sections are tested in both spreadsheets in order to verify the effect of variations between the equations of the current standard and the review document. Next, comparative graphs are plotted with the results obtained. Finally, it is noted that the review document affects the design of compressed elements because the calculation procedure has changed, especially in checking local buckling. In addition, this research can be used by professionals who wish to examine how the review document affects the design of steel structures.