Abstract
To explore the carbonation effect on the design parameters of a bridge deck link slab made by ecological high ductility cementitious composites (Eco-HDCC), flexural and compressive properties of Eco-HDCC were studied. Besides, the carbonation front and pH profile in the pore solution of Eco-HDCC specimens with different carbonation ages were determined. Results indicate that the ultimate flexural strength of Eco-HDCC has little change as carbonation age increases, and first cracking strength increases for carbonation ages of 3 d∼7 d, then decreases. The ultimate deflection of Eco-HDCC after being carbonated is higher than that of the virgin specimen. Besides, as the carbonation age prolongs, the compressive strength and elastic modulus of Eco-HDCC slightly increase. In addition, with the increase of the carbonation age, carbonation front of Eco-HDCC increases while the pH value of the pore solution decreases. When the depth ranges are 15 mm∼25 mm and 37 mm∼40 mm for carbonation ages of 56 d, the pH values are 10.4 and 11.2, which may destroy the passive film of the steel bar. Moreover, the mechanical property parameters for the design of the link slab made by Eco-HDCC can be selected according to non-carbonated material for the purpose of safe and conservative design. The corrosion-resistant steel bar or fiber-reinforced polymer (FRP) bar could be a promising choice to prevent steel bar corrosion.