Fatigue behavior of corroded reinforced concrete continuous beams with multi-intervention system

The corrosion of steel rebars in reinforced concrete (RC) structures will lead to the deterioration of fatigue performance and fatigue life. For the sake of resolving the corrosion problems of RC structures, the Impressed Current Cathodic Protection (ICCP) and Structural Strengthening (SS) techniques are often applied to repair the corroded RC structures. In this study, the ICCP-SS techniques are combined to retrofit the deteriorated RC continuous beams by using the carbon-fabric reinforced cementitious matrix (C-FRCM), and the C-FRCM composites comprised of carbon fabric mesh and inorganic cementitious matrix will served as anodic material for ICCP and the structural strengthening material in the ICCP-SS multi-intervention system. By analyzing the test results of fatigue life, failure mode, cracks in concrete, mid-span deflection, tensile strain of steel rebars and internal force redistributions of the test beams under fatigue load, the influence of reinforcement corrosion and the ICCP-SS retrofitting method on the fatigue performance of RC continuous beams were discussed. The test results showed that the strengthening effect of C-FRCM composites can reduce the generation of cracks in concrete and improve the flexural rigidity as well as fatigue life of the continuous beams effectively, however, the improving effect will decrease for the specimens with higher circulated charge density along with a higher polarization effect of C-FRCM composites.