Investigation on Strength Durability and Antimicrobial Resistance of Cementitious Systems for use in Marine Conditions

Abstract

Microbial-induced corrosion (MIC) is a problem caused by acidophilic newlinemicroorganisms that deteriorate concrete. The reinforced concrete (RC) newlinestructures built in marine environment are severely impacted by MIC, costing newlinebillions of dollars in maintenance and repairs. Better resistance to MIC has newlinebeen demonstrated by the modification of concrete materials through the newlineaddition of chemical and mineral admixtures. Furthermore, cathodic protection newlinesystem is a well-established method for corrosion protection in steel structures newlineexposed to marine environments and have recently been extended to RC newlinestructures. This study evaluated the performance of chemical admixtures in newlinecementitious systems based on their (a) strength, (b) durability, and (c) newlineantimicrobial resistance to provide protection against MIC. In addition, the newlinestudy attempted to assess the performance of a sacrificial anode cathodic newlineprotection (SACP) system for RC structures exposed to a simulated marine newlineenvironment to control corrosion of steel rebar due to MIC. Based on the newlinefindings of the present study, it can be concluded that incorporation of a sodium newlinenitrite-based corrosion inhibiting admixture (SNI) improves the antimicrobial newlineperformance of cement mortar in addition to its mechanical and durability newlineperformances. Hence, a 2% by weight of binder dosage of SNI is newlinerecommended for enhanced antimicrobial resistance of concrete structures in newlinethe marine environment. In addition to the SNI, the SACP system can be newlineinstalled on RC structures as a second line of defence to further improve newlinecorrosion resistance. However, the combined mechanism of the SNI and newlineSACP system in RC structure has scope for further research. newline