Influence of corrosion and cracking on bond behavior and strength of reinforced concrete members

Pullout and beam tests have been carried out to study the influence of reinforcing bar corrosion and cracking on bond behavior and bond strength of reinforced concrete members. Pullout tests are used to simulate severe local corrosion, and beam tests to simulate relatively uniform corrosion, along the reinforcing bar surface. Bond behavior is studied at different stages of reinforcing bar corrosion: noncorrosion, precracking, cracking, and postcracking levels. It has been found that the induction of 0.2 percent polypropylene fibers, by volume into concrete improves the bond resistance of concrete, especially at postcracking levels of corrosion; this is due to the reduced level of damage at the concrete-steel interface and to an intrinsic contribution in improving the confining and holding capacity of the surrounding concrete for the reinforcing bar.