Structural performance of shear-critical RC deep beams with corroded longitudinal steel reinforcement

The effect of corrosion of longitudinal reinforcement on the structural performance of shear-critical reinforced concrete (RC) deep beams was experimentally investigated. A total of eight medium-scale reinforced concrete beams were constructed. The beams measured 150 mm wide, 350 mm deep and 1400 mm in length. The test variables included: corrosion levels (0%, 5%, and 7.5%), existence of stirrups and FRP repair. Six beams were subjected to artificial corrosion whereas two beams acted as control un-corroded. Following the corrosion phase, all beams were tested to failure in three point bending. The test results revealed that corrosion of properly anchored longitudinal steel reinforcement does not have any adverse effect on the behaviour of shear critical RC deep beams. Corrosion changed the load transfer mechanism to a pure arch action and as a result the load carrying capacity was improved. A strut and tie model was proposed to predict the failure loads of shear-critical RC deep beams with corroded longitudinal steel reinforcement. The predicted results correlated well with the experimental results.