This paper reports part of the results from ongoing research on the use of fibre reinforced polymer (FRP) sheets in rehabilitation of corrosion damaged reinforced concrete columns. Understanding the effects of externally wrapped FRP sheets on the corrosion activity in reinforced concrete columns is the main objective of this work. Fifty-six standard-size cylinders (152x305mm) reinforced with both longitudinal and transverse reinforcement are being tested under different combinations of corrosive environment and wrapping schemes. Twenty-four cylinders were corroded electrochemically by applying a constant impressed current of 25 μA/cm~2, another set of 23 cylinders were subjected to an extremely harsh environment of wet-dry cycling using 3% NaCl salt solution under a steady temperature of 55°C in a controlled chamber. The behaviour of the corroded cylinders was compared with those of eight control cylinders. Carbon fibre sheets (CFRP) were applied on some of the cylinders either at the start of the testing or at different intermediate stages. The response of the specimens to the aggressive environment was monitored using several techniques including half-cell potential, linear polarization resistance (LPR), radial expansion, and crack mapping. At the end of each exposure stage, the cylinders will be tested to failure in compression where lateral and axial deformations will be measured. The experiment will be conducted in three stages for 100, 200, and 300 days of exposure to harsh environment, and for three levels of steel loss of 1.5, 3, and 5% for impressed current corrosion. Results from the first stage of testing are reported in this paper.
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