Análise comparativa do dimensionamento de uma viga ao esforço cortante segundo a ABNT NBR 6118:2014 e o FIB MODEL CODE 2010

Abstract

Due to the great need for economy and efficiency in engineering, technical standards are necessary to guarantee the best performance and safety in practical applications, resulting in the need to seek constant updates. The present study aims to analyze the design of transverse reinforcement in a reinforced concrete beam through two standards, namely NBR 6118:2014 and FIB MODEL CODE 2010. Comparisons will be made through a complete review of the calculations applied in the two norms studied, evaluating the sizing differences present in each and comparing the results in order to define the most satisfactory and applicable method in practice. The calculated methods present differences in their methodologies, the Brazilian standard adopts the Ritter-Mörsch lattice theory as a basis, while the FIB MODEL CODE 2010 uses the Modified Compression Model (MCFT), the calculation variables present distinctions from longitudinal deformations to considerations of complementary mechanisms, due to this the results between each method are presented with great difference in the percentage of necessary reinforcement. Methods that consider concrete as a complementary mechanism and adopt smaller compression angles are less conservative and more applicable in practice. Thus, it is noted that the most economical method is the third level of approximation of the FIB, however, due to maximum spacing restrictions, the calculation model II of the NBR is equal to it, presenting the same economy.