Nano TiO2-engineered anti-corrosion concrete for sewage system

Abstract

In this study, anti-corrosion concrete for sewage system was developed with nano TiO2 (NT) and reactive powder concrete (RPC). The corrosion resistances of NT modified RPC (NTMRPC) in high concentration enhanced sewage were investigated from the perspectives of biological, physical and chemical corrosion resistances, respectively. In addition, mechanical properties of NTMRPC after sewage corrosion were also studied. Research results indicated that NT can endow RPC with antimicrobial property through their microorganism biodegradation properties. The inhibition and elimination rates of NTMRPC to its surface microorganisms were 37.35% and 80.93%, respectively. After sewage corrosion, the surface roughness, mass loss and deterioration depth of RPC were decreased by 62.57%, 15.48% and 18.44% due to the NT inclusion, respectively. In addition, the pH values of RPC in the deterioration depth ranges of 0-3 mm and 3-6 mm were increased by 11.45% and 23.62%, respectively. NT can restrain the strength deterioration of RPC in high concentration enhanced sewage. This may be due to the improved sewage biological anti-corrosion performances of RPC by inhibiting/eliminating the microorganisms on the surface of RPC as well as the enhanced sewage physical/chemical anti-corrosion performances of RPC by improving the compactness of RPC.