Study on water and chloride transport in cracked mortar using X-ray CT, gravimetric method and natural immersion method

Concrete structures are frequently suffered to physical and chemical damage in the service period and then cracking is unavoidable. Cracks provide rapid access to aggressive agents and have a significant effect on the durability and service life of concrete structures. In this work, water and chloride transport in cracked mortars were investigated systematically. Firstly, the dynamic process of water transport in cracked mortars was visually monitored by X-ray CT and water absorption of cracked mortar was also quantitatively investigated by the gravimetric method. Later, chloride transport in saturated and unsaturated cracked mortars was studied by natural immersion method. What's more, the effect of gravity on chloride transport in cracked mortar was considered in this study. The results show that the threshold crack width for water absorption of cracked mortar is 0.1 mm. The effect of crack width on chloride transport in saturated and unsaturated mortars is different. The gravity effect improves the rate of chloride transport in cracked mortars.