Neutron diffraction as a tool to monitor the establishment of the electro-osmotic flux during realkalisation of carbonated concrete

Realkalisation is an electrochemical technique for repairing concrete structures damaged by rebar corrosion due to carbonation. The treatment aims at restoring alkalinity of the concrete by application of a continuous current between the rebar, acting as a cathode, and an external auxiliary electrode placed in a carbonate solution and connected to a positive pole of a power supply. Here we report the application of neutron diffraction in the in situ monitoring of a realkalisation treatment, analysing at the same time the development of the electro-osmotic flux and the microstructural variations in the surroundings of the rebar