Multi-scale Carbon-admixtures Enhanced Cementitious Anodic Materials for the Impressed current Cathodic Protection of RC Structures

摘要

Corrosion of the reinforcing steel is one of the most important metrics which severely deteriorate thedurability of reinforced concrete (RC) structures. The anode performance is the critical factor toguarantee the reliability and serviceability of the impressed current cathodic protection (ICCP) systemfor RC structures. The multi-scale carbon-admixtures, i.e., carbon nanotube (CNT), carbon black (CB)and carbon fiber (CF), are used to enhance the conductivity of cementitious composites and then toprepare the excellent anode for ICCP system. The percolation threshold for each carbon-basedcementitious composite is tested, and then the optimal formula with these three multi-scale carbon- admixtures is obtained. Furthermore, the conductive network formed by CNT, CB and CF in theconcrete is analysed by the experiments of scanning electron microscope (SEM). Finally, theaccelerated polarization experiments are carried out to investigate the serviceability of the cementitiousanodes. The results indicate that the multi-scale carbon-admixtures enhanced cementitious compositeshave significant potential advantages to be used as the anodic materials for the ICCP system of RCstructures.