Dual function carbon fibre strengthening and cathodic protection anode for reinforced concrete structures

A novel technique has been proposed and researched in which carbon fibre reinforced polymers (CFRP) are employed to provide both structural strengthening and electrochemical corrosion protection to reinforced concrete (RC) elements suffering from corrosion related damage. CFRPs fabric or rod was used for both flexural strengthening of pre-corroded reinforced concrete beams and operated in a dual functional capacity as an impressed current cathodic protection (ICCP) anode. After a period of ICCP operation at high current density (>64mA/m2 of steel surface area for rod and >128mA/m2 of steel surface area for fabric), the beams were subjected to flexural testing to determine the load-deflection relationship. The potential decays of the steel met recognised ICCP standards and the CFRP remained effective in strengthening the corroded reinforced concrete beams. The ultimate strength of the dual function CFRPs reduced slightly when compared with control reinforced specimens used for strengthening only. This is attributed to the application of the ICCP at high current densities influencing the bond at the concrete/CFRP interface. A number of methods for maintaining and enhancing bond are presently being investigated, together with the optimisation of current densities for operating the CFRP anodes