Axial compressive responses of concrete canvas and CFRP reinforced corroded concrete short columns

Abstract

To evaluate the axial compression performance of corroded concrete short columns reinforced by concrete canvas (CC) and carbon fiber reinforced polymer (CFRP), a total of 16 specimen sets with different reinforcement forms and corrosion rates are designed and examined in this paper. Specimens are subjected to electrochemically-induced corrosion before being mechanically tested under the compressive load. The assessed variables are theoretical corrosion rate (0, 5%, or 10%), number of CFRP wrapping layers (0, 1, 2, or 3), and number of CC layers (0 or 1). Through the signal localization of acoustic emission (AE) and the variation in characteristic parameters, it is found that the presence of CC changes the failure morphology of the specimen and improves the uneven deformation of concrete in the core area. Also, under the same number of CFRP wrapping layers, the peak stress of the CC and CFRP jointly reinforced specimens is reduced by about 10% but has a more than 70% increase in the ultimate strain compared with those of CFRP reinforced only, which proves that the jointly reinforced method exhibits high plasticity deformation ability. With an increase in corrosion rate, compared with the uncorroded specimens, the peak stress of JC specimens decreases by more than 6.9% but the ultimate strain increases by more than 15.4%. The JC specimens’ peak stress and ultimate strain models are then determined through fitting, from which a good correlation with those observed is witnessed. The comparison shows that the model has good accuracy and can provide a theoretical basis for further research for CC- and CFRP-reinforced corroded concrete short columns.