Simple and detailed modeling of corrosion‐affected slender shear critical RC beams

Abstract The corrosion of steel bars compromises both the safety and the serviceability of reinforced concrete (RC) structures. Consequently, reliable tools are required to estimate the detrimental effects of corrosion on the structural response of RC members subjected to transverse loads. Although the literature provides a substantial number of analytical studies on the behavior of RC beams with corroded reinforcement, most of these investigations rely on sophisticated and computationally demanding approaches—typically nonlinear finite element analyses—which also require significant analyst expertise. In this study, some analytical models, selected according to their level of complexity, are applied to evaluate the shear strength or to capture the global response of RC beams affected by steel corrosion and subjected to shear forces. The ability of these models to reproduce experimental results available in the literature for shear critical beams with corroded reinforcement is assessed and related to the complexity of the adopted formulations. In particular, the accuracy of formulations proposed in the literature and/or included in Model Code 2020 for estimating the shear strength of beams with corroded steel reinforcement is examined. An interactive web application is developed with the database and all the calculations. Furthermore, the Level of Approximation IIb approach described in Model Code 2020—originally formulated for non‐damaged RC members and based on the additive contribution of shear‐resisting mechanisms—is extended here to corroded RC beams. The extension explicitly incorporates corrosion‐induced damage through the calculation of effective beam width and residual stirrup area. A cross‐sectional model, previously developed by the same authors, is enhanced by updating the constitutive formulations used to quantify the effects of corrosion on the compressive strength of concrete and on the efficiency of the transverse steel reinforcement. The accuracy of the modified cross‐sectional model is assessed by comparing experimental results with numerical predictions obtained from advanced nonlinear finite element analyses. Finally, modeling strategies for RC beams with corroded reinforcement are discussed.