Chloride Migration Coefficient of Cracked Mortar Incorporating Self- Healing Materials: New Generation of Construction Materials

One of the key factors for early deterioration of most concrete structures subjected to marine and coastal environment is the corrosion of steel bar induced by chloride ions. Cracks present in concrete would significantly accelerate the penetration of chloride ions into concrete. Thus, the self-healing of cracks has a great impact on the resistance of chloride penetration and the
durability of the concrete structures. In this study, for the characterization of self-healing capacity with regard to the durability of concrete structures, rapid chloride migration (RCM) tests were conducted to measure the chloride migration coefficients of mortar specimens made of OPC and special binders incorporating self-healing materials. Chloride ion concentration in the upstream cell of ASTM C1202 test set-up was measured for 36 hours, and the chloride migration coefficients were calculated based on the change rate of chloride concentrations in the steady-state condition. Test results reveal that self-healing can reduce the penetration of chloride ions and improve the resistance to chloride ingress of the cracked mortar specimens. The self-healing efficiency can be defined in terms of the decrease of chloride migration coefficients and the RCM test can be a satisfactory method to evaluate the self-healing capacity
of cement-based materials.