Effect of Steel and Prestressed GFRP Bars on Bending and Shearing Failure Modes in Reinforced Beams

Abstract

In recent years, there has been significant progress in using FRP materials as masonry in civil engineering. In this regard, researchers have investigated the behavior of reinforced beams with FRP and steel bars. One way to enhance these sections is to prestress FRP bars to increase sections' bending and shearing strength. Reinforcing with a hybrid bar is a new method in which GFRP and steel bars are combined. In this research, the type of GFRP bars is first determined, and then samples are prestressed. Samples are modeled using LS-DYNA software. Bending and shearing failure modes of reinforced beams with FRP, GFRP, steel, and hybrid bars are analyzed, and finally, load-displacement behavior and crack width are compared. By studying the beam's bending and shearing behavior and failure modes, we found out that using hybrid bars decreases the number of cracks Wider than 0.35 mm in the same displacement and greater loading capacity. By comparing load-displacement diagrams of samples, we conclude that the sample reinforced with hybrid bars has the best function. We can benefit from the anti-corrosion property of GFRP bars by arranging the reinforcements properly. The loading capacity of the sample can be increased by about 65% by prestressing them. Consequently, the displacement of samples decreased.