Design of SFRC beams without stirrups according to the Brazilian standard NBR 6118 with abacuses

In this study, design abacuses were proposed to evaluate the possibility of replacing the minimum shear reinforcement of reinforced concrete beams with steel fibers. For this purpose, computations were made to evaluate the shear strength of 240 experimental tests of concrete beams reinforced with steel fibers (SFRC) using code formulations, literature, and international standards to define which model is in better agreement with the experimental data. Thus, once this expression was identified, SFRC beam design abacuses were developed to determine the amount of steel fibers needed to replace the minimum shear reinforcement according to the Brazilian Standard. Through statistical analysis, the model that best correlated with the experimental test results was selected. In the last section, the selected model is applied to the SFRC beam with rectangular sections, and the design abacuses are shown. Finally, it is concluded that the developed abacuses facilitate decision-making in the design of SFRC beams and, may become an essential tool for the design of these structural elements.