An optimum strategy for FRP-strengthening of corrosion-affected reinforced concrete columns

In order to ensure safety of deteriorated reinforced concrete (RC) structures, an effective rehabilitation plan is essential. Although considerable research on strengthening of RC structures using Fiber Reinforced Polymers (FRP) composites has been undertaken, prediction of optimum strengthening time has not adequately been studied. This paper presents a methodology for optimal strengthening of corrosion-affected RC columns. An optimization problem based on minimization of total cost is formulated, from which optimum strengthening time and number of required FRP layers can be obtained. The results from a worked example show that an optimum solution to the formulated strengthening problem exists, and it is sensitive to the corrosion rate and cost of failure to cost of strengthening ratio. The proposed approach is useful in the development of an effective strengthening schedule for existing corrosion-affected RC columns, and could benefit the asset managers and structural practitioner. © 2019 Taylor & Francis Group, London.