INVESTIGATION OF CORROSION DAMAGE IN CFRPCONFINED REINFORCED CONCRETE MEMBERS

摘要

Confinement with Carbon Fiber Reinforced Polymer (CFRP) wrapping is widely recognized as an effective means to retrofit and repair reinforced concrete members. However, its relationship with corrosive reactions that take place in steel reinforcement embedded in concrete is not fully understood. CFRP wrapping acts as a diffusion barrier, retarding the ingress of corrosive agents, but there is little information about its effect on the reaction itself. There is also evidence that confining the natural tendency to expansion of corrosion products forces them to form a protective coating around the reinforcement bars. The project hereby presented aims to isolate the different variables that play a part in these phenomena and assess the efficiency of CFRP confinement both as a pre-corrosion and a post-repair corrective method. A series of tests on reinforced concrete specimens submitted to different corrosive conditions and wrapping combinations is presented. Corrosion rates, expansive strain build-up, cracking and load-carrying capacity decrease of the specimens due to corrosion are to be measured and followed along the whole process. These data will be used to develop a predictive model with Finite Element techniques featuring a mechanical behavior model for solidified corrosion products, including the relation between external confinement and compressive modulus.