Application of carbon-fiber-reinforced polymer anode in electrochemical chloride extraction of steel-reinforced concrete. (1st September 2016)

• Record Type: Journal Article
• Authors: Zhu, Ji-Hua; Wei, Liangliang; Wang, Zhaohua; Liang, Cheng Ke; Fang, Yuan; Xing, Feng
• Is Part Of: Construction & building materials. Volume 120(2016)
• Page Start: 275
• Page End: 283
• Publication Date: 2016-09-01
• Subjects: CFRP carbon-fiber-reinforced polymer -- ECE electrochemical chloride extraction -- EDS energy-dispersive spectroscopy -- ICCP impressed current cathodic protection -- PVC polyvinyl chloride -- SEM scanning electron microscopy -- D diameter of steel bar embedded in concrete -- L1 test region of steel bar -- L2 masked region of steel bar -- Asteel test area of steel bar -- i current density applied to the test area of steel bar -- w12_Cl- total chloride extraction on the 12th day -- w28_Cl- total chloride extraction on the 28th day -- fmax maximum bond obtained in pullout test -- δloss bond loss of test samples due to ECE treatment -- wCl- chloride extraction ratio at two-day intervals -- mCl- mass of chloride obtained by titrating the electrolyte solution at two-day intervals -- MCl- total mass of chloride in the NaCl-modified mixing solution used for concrete casting -- nOH- concentration of OH− -- pH pH value of solution -- Pmax maximum drawing force -- f0_max maximum bond of control sample in each series -- kCl- Cl−/cement ratio after ECE treatment -- W Cl−/OH− ratio after ECE treatment -- f steel–concrete bond obtained in pullout test -- Pcr critical load in a typical pullout load vs. displacement curve -- U∗ displacement in a typical pullout load vs. displacement curve; Electrochemical chloride extraction -- CFRP -- Pullout tests -- Microscopic examination; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2016.05.103
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Chloride was extracted from steel-reinforced concrete via electrochemical chloride extraction (ECE). Carbon-fiber-reinforced polymer (CFRP) served as external anode. Steel–concrete bond loss varied with samples' water–cement ratio and applied current density. CFRP anode performance showed no significant degradation after ECE treatment. ECE efficiency was compatible with that shown using activated titanium mesh anode. Abstract: A carbon-fiber-reinforced polymer (CFRP) was adopted as an external anode in the electrochemical chloride extraction (ECE) of cylindrical steel-reinforced concrete samples with different water–cement ratios and chloride introduced during casting. Three constant current densities were applied between the steel cathode and CFRP anode, with the internal steel bar used as the cathode. The chloride extraction ratio, proportion of residual chloride, and Cl − /OH − ratio were obtained to assess the ECE efficiency; pullout tests were conducted to evaluate the post-ECE bonding characteristics between steel and concrete. A microscopic evaluation of both concrete and CFRP showed that the CFRP anode did not experience severe degradation after ECE. Comparison of the performance by using activated titanium mesh anodes confirmed the feasibility of ECE with an external CFRP anode.