Electrodeposition to reduce the impact of cracks on steel corrosion in concrete

Artikel i vetenskaplig tidskrift, 2026

Electrodeposition has been proposed as a method to promote mineral precipitation in cracked reinforced concrete, potentially limiting ingress of aggressive agents and delaying corrosion initiation. However, the extent to which electrodeposition-induced crack filling improves corrosion resistance under marine exposure, and the influence of electrolyte composition on the effectiveness and mechanism of electrodeposition, remains overlooked.This study investigated deposition behaviour of electrodeposition in either artificial seawater or Ca-Mg nitrate solution and evaluated corrosion performance of electrodeposition-treated (2x3) and non-electrodeposition-treated (references, 2x2) specimens during artificial seawater exposure.Reinforced concrete cylinders containing tensile-induced transverse cracks underwent three-month electrodeposition treatment, followed by a three-month artificial seawater exposure. Crack filling and deposition patterns were examined using X-ray computed tomography (XCT), optical microscopy, and μXRF elemental mapping, while corrosion behaviour was assessed through half-cell potential monitoring and post-exposure CT. Analytical interpretation was further used to interpret observed electrodeposition behaviour.A difference in Ca²⁺ and Mg²⁺ ion concentrations between the Ca-Mg nitrate solution and artificial seawater results in different crack-filling behaviour. Electrodeposition in Ca-Mg nitrate solution resulted in extensive internal crack filling reaching the steel-concrete interface, independent of crack geometry and width (maximum surface crack width 0.75 mm), and no corrosion was observed. In contrast, electrodeposition treatment in artificial seawater resulted in deposits primarily near the crack mouth and an influence of crack geometry. In these specimens, corrosion was prevented in two specimens and reduced in the third. The findings demonstrate that electrodeposition can delay corrosion initiation in cracked concrete when sufficient internal crack filling is achieved.