Improved degradation relations for the tensile properties of naturally and artificially corroded steel rebars

In the present study, the tensile properties of naturally and artificially corroded steel rebars of different grades and diameter are experimentally investigated. Naturally corroded steel round rebars were acquired from 54-year-old inland corridor structure, exposed to carbonation and artificially corroded rebar were obtained by subjecting bare rebars to chloride attack through an impressed current based artificial corrosion. Mass losses were in the range of 0.81% to 79.64% for naturally corroded rebar and 9.95% to 50.51% for artificially corroded rebar. In the case of artificially corroded rebars, variations in rib loss with the level of corrosion were also captured. Effect of corrosion on elastic modulus, ductility, yield and ultimate stresses of naturally and artificially corroded rebar were studied. Based on the tensile test results, degradation equations were formulated to estimate the yield and ultimate stresses of corroded rebar knowing the properties of uncorroded rebar. Finally, proposed equations were validated with the results obtained from the literature study. The comparison revealed that the equations proposed in this study provide improved prediction of yield and ultimate stresses of corroded rebar. (C) 2020 Elsevier Ltd. All rights reserved.