ABSTRACT
The carbonation reaction of concrete leads to the deterioration of structural performance, reduces the protective effect on steel bars, and thus affects the service life of bridges. This study discusses the process of concrete carbonation in bridges and the corrosion of reinforcing steel, introduces several theoretical and experimental models, and proposed some measures to decrease damages. Results show that the factors affecting the durability of reinforced concrete structures include carbon dioxide concentration, relative humidity, cement type, and water-cement ratio. Numerical models are established to predict the depth of carbonation, which indicates the thickness of the protective layer of reinforcement and the life of the reinforced concrete bridges. The empirical models based on the water-cement ratio and the compressive strength of the concrete are early predictions models of carbonation. In addition, multi-factor empirical models, based on diffusion theory and experimental results models are established to improve the prediction accuracy. To improve the life of reinforced concrete bridges, the bridges are constructed according to the design specifications through construction management. The quality of construction materials needs to be controlled, such as choosing the right materials, controlling the water-cement ratio, and the frequency of pounding to prevent concrete carbonation.
