NUMERICAL STUDY ON HYBRID REINFORCED CONCRETE BEAM WITH RECTANGULAR SPIRAL SHEAR REINFORCEMENT

Abstract

Hybrid reinforcement is partial replacing of steel rebar with other bars such as fiber reinforced polymer (FRP) rebar in civil engineering structures. FRP reinforced concrete structures adopt non-corrosive nature and high tensile strength with lightness. However, FRP is low modulus of elasticity which tends to brittle. Hybrid reinforced concrete beam with spiral shear reinforcement offers advantages by replacing ties with rectangular spiral shear reinforcement. This thesis work presents numerical investigation on hybrid reinforced concrete beam with rectangular spiral shear reinforcement. Experimental result reported in literature was used for validation analysis using ANSYS finite element analysis software program. Further, parametric studies were performed on spiral spacing, span to depth and spiral angles of inclination, bar arrangement and effective reinforcement ratio by developing FE models of twenty hybrid RC beams with rectangular spiral shear reinforcement and four control RC beams with closed stirrups under four-point bending loading. The maximum load of FE analysis and the experimental results shows good agreement with a minimum deviation of the percentage error is 0.4% or corresponding ratio of ultimate loads of the tested specimen. Replacing the tie with rectangular spiral shear reinforcements enhanced the load-carrying capacity of the hybrid reinforced concrete beams in between (0.5- 11.12) in percent and mid-span deflection at about (0.89-12.12) in percent. The spiral angle 800 is most effective angle of inclination to determine the load carrying capacity of hybrid beam with rectangular spiral shear reinforcement. Hybrid RC beams with rectangular spiral shear reinforcement spiral spacing 200 mm exhibited (1.27-11.3) in percent less load resistance than corresponding beam with spiral spacing 150 mm