What is the maximum spacing of shear reinforcement and why is this restriction?
As per Cl 18.104.22.168; ≤ 0.75 d for vertical stirrups ; ≤ d for inclined stirrups and in no case shall exceed 300 mm. This is to
- ensure that at least one stirrup crosses an inclined crack due to shear and
- to provide better lateral confinement to concrete.