Flexural behavior of two-layer concrete beam reinforced with steel and GFRP rebars

Abstract Two-layer composite beams using plain concrete reduce structural component costs and improve flexural performance. The research will analyze the flexural behavior of concrete beams reinforced with two kinds of bars. Four specimens used a single layer of conventional and high-strength concrete, whereas the other four employed a two-layer beam integrating both types of concrete. This research included two types of reinforcement: steel and glass. The upper layer used 62 MPa high-strength concrete, while the lower layer comprised 38 MPa regular concrete. Bilayer beams provide a greater ultimate load capacity than one-layer concrete beams. The flexural capacity of high-strength and bilayer steel-bar beams exceeded that of conventional concrete beams by 9.46 and 19.76%, respectively. Bilayer beams support 18.85% more loads than conventional concrete beams.