Tensile behavior and flexural performance of polarized CFRCM-strengthened corroded RC continuous beams

The flexural characteristics of corroded reinforced concrete (RC) continuous beams strengthened through a synergistic application of impressed current cathodic protection (ICCP) and structural strengthening (SS) techniques are investigated. First, the uniaxial tensile behavior of carbon fabric reinforced cementitious matrix (CFRCM) was evaluated under various current densities and durations. Polarization response was discussed and the piecewise tensile model was developed. Finite element models (FEMs) were then established to predict the flexural response of the specimens strengthened with polarized CFRCM plates. The critical moment and load values were validated against experimental results, and the ultimate bending moments were assessed using both bilinear and proposed piecewise tensile constitutive models. It was found that there was a distinct decline in the tensile properties of CFRCM plates with increasing charge density, exhibiting significant reductions in tensile strength and ultimate strain when the charge density reached 15.00 × 10⁵ C/m². The FEMs accurately reproduced the flexural behavior of strengthened specimens, successfully capturing the failure modes, characteristic moments, and loads. The proposed piecewise tensile constitutive model for polarized CFRCMs demonstrated superior accuracy over the bilinear model recommended in ACI 549.4R-20.