Effect of cover depth, w/c ratio, and crack width on half cell potential in cracked concrete exposed to salt sprayed condition

Half cell potential is a widely adopted Non-Destructive Technique in field to evaluate the corrosion of steel in concrete structures qualitatively. If the concrete is exposed to chloride attack, the cracks on concrete surface will rapidly accelerate the steel corrosion due to the intrusion of chloride ions and water permeation. This paper presented the test results of half cell potential evaluation in cracked concrete exposed to chloride attack. The test parameters taken were cover depth (30 mm and 60 mm), w/c ratio (0.35, 0.55, and 0.70), and crack widths (0.0-1.5 mm). To accelerate corrosion cyclic salt spraying test was performed on reinforced concrete beams for the duration of 35 days. Half cell potential (HCP) and corrosion state of rebar were evaluated. From the test results, HCP evaluation technique was proposed considering the effects of w/c ratios, crack width, and cover depth. Furthermore required cover depths for anticorrosive condition were obtained through chloride penetration analysis and the results were compared with previous study.