Behavior of composite rectangular RC beams encased with steel I-section under flexure

The current paper presents the results of an experimental study conducted on flexural behaviour of steel-concrete composite beams, each beam consisting of rectangular Reinforced Concrete (RC) section encased with a steel I-section. A new type of composite beam prepared with GFRP reinforced concrete encased with steel section was proposed and studied which can provide better corrosion resistance. A total of six beams, of uniform size 150 mm wide, 200 mm deep and 1000 mm long, were cast and tested under four-point bending. Of six beams cast, three beams were reinforced with GFRP rebars and the remaining three beams were reinforced with steel rebars. Three different grades of concrete were used for casting. The behaviour of steel-concrete composite beams reinforced with steel and GFRP rebars were observed. The observation made were load versus mid-span deflection, concrete strain, strain of steel I-beam. The test result indicates that using encased steel sections can provide a significant improvement in load carrying capacity and stiffness of RC beams.