A model for predicting time-dependent chloride binding capacity of cement-fly ash cementitious system
A model for predicting time-dependent chloride binding capacity of cement-fly ash cementitious systems was proposed. The proposed model took into account both chemical binding and physical binding. Chemical binding was considered to depend on the amount of unhydrated aluminated and aluminoferrite phases while physical binding depended upon the quantity of hydrated and pozzolanic products. The concept of time-dependent chloride binding capacity was introduced in the model with the consideration of curing time and chloride exposure period. The chloride binding of cement pastes and cement-fly ash pastes under different curing times and chloride exposure periods were tested. Three types of cement and two types of fly ash were used. From the experimental results, time-dependent behavior of chloride binding capacity was observed.