Shear Strength of Reinforced Concrete Beams

A new equation for the shear strength of non-prestressed reinforced concrete (RC) beams is proposed. The proposed equation is consistent with the shear strength equation for prestressed concrete (PC) beams proposed by Laskar el al. Both equations have the same variables for shear span-depth ratio (a/d)(-0.7), the strength of concrete root f(c)', and the web width b(w) in the V-c term, as well as the same expression A(v)f(vy)(d/s - 1) in the V-s term. The only difference is that the web effective depth d in the V-c term of PC beams is replaced by the depth of the web compression zone c of RC beams. In this way, the shear design for RC beams and PC beams can be unified both in physical conception and in design equations. The proposed equation is shown to be more predictive and more consistent when compared with the ACI method and the Frosch method using 313 test beams found in the literature.