Investigação teórico-experimental de vigas armadas com barras de polímero reforçado com fibra de vidro (PRFV) submetidas à flexão

Abstract

The use of composite materials as an internal or external reinforcement alternative for concrete structures has been growing significantly over the years and has great applicability in civil engineering. With the advancement of materials technology, there is a great availability of FRP (Fiber Reinforced Polymer), marketed both as meshes and in profiles or rebars. FRP rebars present characteristics of corrosion resistance and nonelectrical conductivity, which, when used in aggressive environments, cause not only a reduction in maintenance costs, but also an increase in the durability of the structure. This study aims to analyze the theoretical and experimental behavior of reinforced concrete beams with FRP strengthening, according to the ACI guidelines 440.1R-2015. Three reinforcement rates were adopted in order to configure the ruin by the rupture of the reinforcement of GRP, ruin by the crushing of the concrete and ruin according to the balanced condition. The experimentation began with the study of concrete dosage and characterization assays of the GRP. The beams molded according to the three reinforcement rates were tested to four point bending, which were 20 x 20 x 135 cm and instrumented by strain gauges and LVDTs (Linear Variable Differential Transformer). The results show the displacements found for each reinforcement rate, the deformations of the materials during the loading application, as well as the support capacity of the beams. These results validate the theoretical prediction of the behavior and show the influence of the low elastic modulus of the FRP on the beams deformations.