Effect of loading level on the corrosion resistance of a novel self-healing cementitious composite

Abstract

A novel self-healing cementitious composite SMA-ECC is utilized to enhance corrosion resistance and maintain mechanical properties in chloride environment. The purpose of this study is to investigate the impact of the loading level on embedded steel rebar corrosion and the self-healing performance of SMA-ECC. The study examined the damage conditions, mechanical properties, and rebar corrosion resistance following a loading test. Chloride ingress depth and electrochemical tests were adopted to evaluate the corrosion resistance of the specimens. The findings reveal that SMA-ECC exhibits remarkable self-healing abilities in terms of damage recovery and restoration of mechanical properties. Cracks smaller than 50 μm can achieve a 100 % closure rate in SMA-ECC. It was observed that specimens with less damage (50 %, 70 % damage conditions) displayed improved chloride resistance (SMA-ECC in 50 % damage condition has equivalent corrosion resistance in terms of corrosion current density compared to intact NC control specimens), leading to higher corrosion resistance for SMA-ECC according to the electrochemical test results.