Estudo da influência da modelagem numérica da seção de perfis formados a frio na determinação da carga última pelo Método da Resistência Direta

Abstract

This work aims to investigate the phenomenon of buckling in cold-formed metal profiles of simple U-type (U) and hardened U-type (Ue) used in general under compression, through comparisons between experimental results of collapse load available in the literature and the prediction of the Direct Resistance Method (MRD), which uses as input the critical buckling load obtained numerically in software such as CUFSM. So trying to find correlations between how to model optimally and obtaining the values ​​of critical loads. In addition to comparing experimental results from the literature and theoretical predictions, the work aims to evaluate the influence of modeling the profile section. Thus, the work aims to analyze how the modeling of profile bends with straight corners or curves in the bends interferes in the results of theoretical buckling loads in their different modes. The buckling of a compressed thin-walled profile occurs when it is very slender as a column or when the plates that compose it are slender. This makes the profiles sensitive to instability phenomena such as: local buckling, global buckling and distortional buckling. Through the elaboration of three theoretical models with different characteristics in the profile bends, the behavior between the theoretical models will be analyzed. It will also be discussed which results the variations in the profile folds generate for the different support conditions of the tests extracted from the literature. Due to the wide use in the steel profiles industry, a precise dimensioning must be taken into account for the selection of the most economical sections, keeping the strength and safety requirements without wasting resources.