Shear Behaviour of Ordinary Strength RC Slender Beams

Abstract

Eight full scale reinforced concrete slender beams with identical cross sections and longitudinal reinforcement were tested under two point loading at a shear span to depth ratio of 3.25 to understand the shear behavior of reinforced concrete beams and ascertain a minimum amount of shear reinforcement in beam to attain full flexural capacity before failure. The specimens were divided into four groups based on shear reinforcement ratio. Two samples each were prepared according to ACI code provisions for minimum reinforcement, Zararis’ theory and modified form of Zararis’ equation. The remaining two beams were tested without shear reinforcement for reference purposes. Ultimate shear strengths obtained in this experimental program are compared to the analytical shear strengths calculated according to ACI code, Zararis’ equation and the Modified Zararis’ equation. Test results indicated that, Zararis’ and modified Zararis’ equation give a better prediction of shear capacity of RC beams. The proposed modified equation predicts better shear characteristics as compare to Zararis’ and ACI equation and incorporates all the parameters influencing the shear behavior of beam.