Chloride ion transport and corrosion
This chapter presents three items of importance for predicting chloride ion equilibrium, transport and steel corrosion in concrete. First, thermodynamic states of chloride are discussed with ionized, solid-phase and adsorbed chlorides, and state equations in micro-pores presented in Chapter 3 are formulated for ordinary Portland and mixed cement with pozzolans. Second, a chloride ion transport model is proposed for both sound and cracked concrete, which is linked with Chapter 9 and Chapter 10, along with the nonlinear chloride-binding model in a thermodynamic coupled system. Third, a unifi ed corrosion model is presented for steel reinforcement throughout the life of concrete structures based on an electro-chemical thermodynamic approach, and this model is coupled with structural performance assessment discussed in Chapters 8-10.