Corrosion Activity on CFRP-Strengthened RC Piles of High-Pile Wharf in a Simulated Marine Environment

Abstract

We report test results from an experimental study to investigate the effectiveness of carbon fiber-reinforced polymer (CFRP) against reinforcing steel bar corrosion. Twelve reinforced-concrete pile specimens of 180 mm square by 1,600 mm long were cast. Three pile specimens were corroded to 5% steel mass loss and then strengthened with CFRP sheets; four specimens were strengthened by using CFRP sheets, whereas the remaining five specimens were not strengthened. The specimens were placed in a simulated marine environment, and corrosion was induced by an impressed current technique. At different theoretical corrosion degrees, nondestructive tests were performed to investigate the corrosion activity of the pile specimens, and destructive tests were performed to determine reinforcing steel bar mass loss. Based on the findings, the effectiveness of the CFRP-strengthened RC piles under aggressive marine environmental conditions was established.

Anticorrosion Behaviour ofRhizophora mangleL. Bark-Extract on Concrete Steel-Rebar in Saline/Marine Simulating-Environment

“…In the past decade, numerous studies have deliberated on corrosion problems that are encountered from the in-service environments for steel-reinforced concrete applications [9–30]. These studies lend supports to the knowledge that the environments for steel-reinforced concrete attacks constitute the acidic [9, 12, 16, 30], alkaline [11, 15, 17, 23] and neutral [14, 18, 29] media, wherein environmental agents such as carbonation [20, 25, 28], chloride ions [10, 19, 21, 24], and sulphate ions [9, 13, 17] effects are indicated for the corrosion degradation mechanisms against steel-in-concrete. These have engendered monitoring techniques [26, 27] and solution approaches [20, 22, 29], over the years, for assessing and/or addressing different modes of reinforcing-steel corrosion in concrete.…”

“…These have engendered monitoring techniques [26, 27] and solution approaches [20, 22, 29], over the years, for assessing and/or addressing different modes of reinforcing-steel corrosion in concrete. Some of the proffered solutions include the use of fibre reinforced polymer, stainless steel, protective coating, concrete pore sealers, and corrosion inhibitor as admixture in concrete [14, 26, 31–39].…”

“…Among these corrosion mitigation methods, the corrosion inhibitor admixture in concrete is receiving great attention because it is among the most cost-effective and easily applied technique of tackling concrete steel-rebar corrosion in aggressive environments [14, 19, 22, 23, 29, 30, 40, 41]. However, problems persist on corrosion inhibitor usage, especially, due to the fact that well-known substances for inhibiting corrosion of steel-rebar, such as chromates and nitrites, also exhibited toxicity and hazardousness to the environmental ecosystems [41–43].…”

Cymbopogon citratusand NaNO2Behaviours in 3.5% NaCl-Immersed Steel-Reinforced Concrete: Implications for Eco-Friendly Corrosion Inhibitor Applications for Steel in Concrete

“…Techniques proffered for mitigating chloride-induced steel-in-concrete corrosion include use of steel or concrete surface coating, stainless steel, fibre reinforced polymer encasement, cathodic protection, electrochemical chloride extraction, and corrosion inhibitors [3,[19][20][21][22][23][24][25]. Among these techniques, the use of corrosion inhibitors attracts much preference due to its economically lower cost, labour saving, and ease of applications, all combined with its relative effectiveness at mitigating corrosion of steel embedded in concrete [20,[26][27][28][29][30].…”

“…Among these techniques, the use of corrosion inhibitors attracts much preference due to its economically lower cost, labour saving, and ease of applications, all combined with its relative effectiveness at mitigating corrosion of steel embedded in concrete [20,[26][27][28][29][30]. Applications of corrosion inhibitors can take the form of admixture into freshly cast concrete or it can be applied unto the surface of already cast concrete structures as migratory corrosion inhibitors (MCIs) [31][32][33].…”