Análise do comportamento mecânico do concreto com adição de macrofibras de polipropileno

Abstract

The present study aims to evaluate the mechanical behavior of concrete with and without the addition of polypropylene macrofibers, focusing on post-cracking behavior and the strength gain resulting from the inclusion of different fiber contents. For this research, three different concrete mixes were produced: concrete without macrofibers, concrete with 2 kg/m³ of macrofibers, and concrete with 4 kg/m³ of macrofibers. After molding and curing, the specimens were tested under different types of loading: double punching (ABNT NBR 16939:2021), splitting tensile strength (ABNT NBR 7222:2011), and axial compression (ABNT NBR 5739:2018). The results showed that the concrete with the addition of macrofibers exhibited a considerable increase in strength, particularly in simple compression, in addition to improving the material’s post-cracking behavior by providing greater energy absorption capacity and enhancing its ductility. Thus, it is verified that the incorporation of polypropylene macrofibers into the concrete led to significant improvements in its main mechanical properties, making the composite more resistant to the applied loads as well as to shrinkage and post-cracking processes.