Behaviour of reinforced concrete beams with non-bonded flexural reinforcement

The work presented concerns an investigation of the effect of bond between concrete and longitudinal reinforcement on the behaviour of reinforced concrete beams, without transverse reinforcement, subjected to transverse loading combined with an axial force in selected cases. The results showed that the development of bond anywhere within the shear span inevitably leads to inclined cracking, which is the cause of ‘shear' failure. Similarly, eliminating bond throughout the beam's span was also found not to safeguard against premature failure. On the other hand, allowing the development of bond only within the shear-free region of the beam was found not only to prevent failure within the shear span, but also to allow the calculation of flexural capacity as for the case of beams with steel bonded to concrete throughout their span.