SHEAR REINFORCEMENT EFFECTS ON THE FLEXURAL STRENGTH OF REINFORCED CONCRETE BEAMS

This research devotes to conduct an investigation into the effects of lateral reinforcement on the flexural behaviour of Straight Reinforced Concrete Beam (SRCB). The amount of both longitudinal and lateral reinforcement, beam aspect ratio (h/d) and shear span of concentrated load to depth ratio (a/d), are considered. The experimental work includes casting and testing of fifteen SRCB of normal strength with simple ends. The beams divided into three groups according to h/b ratio which taken equal to (1.5, 2, and 2.5). The experimental results show that for SRCB with h/b equal to 2 and under concentrated load at mid-span the ultimate load carrying capacity increased by (30.8%, and 22.23%) when increasing the shear reinforcement by (50%, and 100%) respectively. Also, the ultimate strength was increased by about 10.38% and 16.53% with increment in shear reinforcement of 50%, and 100% respectively for beams with h/b equal to 1.5 and under two-point load at third point. Finally, the results appear not only increments in the capacity of ultimate load and decrement in the cracks width when decreasing the shear reinforcement spacing but also the ductility of the beams has increased observable.