Light-weight cementitious conductive anode for impressed current cathodic protection of steel reinforced concrete application

•Lightweight cementitious anode for ICCP system using pumice aggregate (PA).•The weight of the anode is reduced by 50%.•Highest conductivity of 0.2 S/cm is achieved at 1.1% addition of carbon fibres.•Lower shift in anode potential at 30% replacement level of PA.

This paper presents the results of a study of the effectiveness of lightweight conductive cementitious mortar as an anode material for impressed current cathodic protection of concrete structures. The anode is made up of pumice aggregate (fine), carbon fibres and cement with MMO-Ti as a primary anode. Accelerated galvanic test, conductivity measurement, dry density and compressive strength were carried out and compared with the cement mortar without fibres. Results have shown that the mortar at 20–30% replacement level of pumice aggregate with 1.1% carbon fibre content is a percolation threshold at which highest conductivity of 0.2 S/cm is achieved. The weight of the anode was found to have reduced to half of the weight of the conventional anodes. Polarisation and impedance studies confirmed the possible use of this material as an anode in cathodic protection of reinforced concrete structures.