Fatigue behaviour and design of corroded reinforced concrete beams intervened by ICCP-SS

To improve the fatigue resistance of degraded reinforced concrete (RC) beams, the present study employs a dual-functional intervention, impressed current cathodic protection and structural strengthening (ICCP-SS). This paper presents the results of an experimental and analytical study of the fatigue performance of corroded simply supported beams with ICCP-SS intervention. The experimental programme comprises 16 RC beams subjected to accelerated corrosion and ICCP followed by four-point bending tests. The test results show that the corrosion of the steel reinforcements in the cathodically protected beams is effectively prevented. More importantly, the ICCP-SS intervention significantly enhances the fatigue resistance of the flexural members. In comparison to those of the corroded beams without any additional measures, the fatigue lives of the treated beams are significantly improved, by as much as 202%. The beams with the ICCP-SS intervention fail due to fatigue fracture of the steel reinforcement followed by a combination of slippage and rupture of the carbon fibre meshes. An amount of ductility is observed at the point of failure of the beams subjected to ICCP-SS intervention. In addition, the experimental results are compared with the predictions of the European and Japanese design codes as well as the Chinese design codes.