COUPLED CORROSION-FATIGUE IN CONCRETE

Abstract

This thesis focuses on the RC structure’s lifespan, which is affected by deterioration due to corrosion–fatigue processes. Corrosion results in cross-section reduction, while fatigue induces the nucleation and crack formation in steel bars. Pitting corrosion initiates the crack while environmental factors change the crack propagation kinematics. Corrosion can affect the residual capacity of an RC beam through several mechanisms, including the loss of the area of the steel reinforcement section, the loss of the concrete section as a result of longitudinal cracking and spalling of concrete, and a reduction in the bond of reinforcement with concrete around it. The compressive strength of Concrete is reduced and the same can be observed when the magnitude of repeated loading and the number of cycles are increased. A model consisting of three dimensions using finite element (FE) analysis in Ansys has been made to replicate beams that are corroded while taking into account all damages due to action of corrosion such as concrete fracture and decrement in area and strength of steel reinforcement. The proposed finite element model included all destructive effects occurs because of corrosion in the beam and uses the suitable empirical models available to replicate the reduction in the research for damages due to corrosion. The software package is employed to simulate the nonlinear behaviour of reinforced concrete beams with tensile reinforcements and stir-ups corrosion degrees of 0%, 4% and 8%. Lastly, The Fatigue Life is analysed and compared for different corrosion levels.