Stray current induced corrosion of steel fibre reinforced concrete

Abstract

Stray current induced corrosion is a major technical challenge for modern electric railway systems. The leakage of stray current to surrounding reinforced concrete structures can lead to steel reinforcement corrosion and the subsequent disintegration of concrete. Steel fibre reinforced concrete has been increasingly used as the railway tunnel lining material but it is not clear if discrete steel fibres can still pick up and transfer stray current in the same way as conventional steel reinforcement and lead to similar corrosion reactions. The corrosion behaviour of steel fibres was investigated through voltammetry tests and electrochemical impedance spectroscopy. The presence of high concentration chloride ions was found to increase the pitting corrosion tendency of steel fibres in simulated concrete pore solutions and mortar specimens. The chloride threshold level for corrosion of steel fibres in concrete is approximately 4% NaCl (by mass of cement) which is significantly higher than that of conventional steel reinforcement

Evaluation Model for the Scope of DC Interference Generated by Stray Currents in Light Rail Systems

“…The AC stray current has been proved to be less dangerous than the DC stray current [5]. In addition to the rise of rail potential [6], the stray current will cause electrochemical corrosion in some of the infrastructure, such as the running rails [7], buried pipelines [8] and concrete structure [9], which overall reduces the safety performance of the light rail system [10]. Three grounding strategies are usually used in the light rail system, which are diode-grounded schemes, directly grounded schemes and ungrounded schemes, respectively [11].…”

Effect of Straw Fiber Modification Methods on Compatibility between Straw Fibers and Cement‐Based Materials

“…At present, the main reinforcements in fiber-reinforced cement-based composites are steel fibers, synthetic polymer fibers, carbon fibers, glass fibers, and asbestos fibers [4][5][6]. However, the problem of the corrosion of steel fibers, the harmful production process of synthetic polymer fibers, and the possibility of pathogenicity of glass fibers have not been well solved [7,8]. us, the poor economy and environmental problems related with the use of these fibers cannot be ignored.…”

Stray alternating current (AC) induced corrosion of steel fibre reinforced concrete

“…From a structural perspective, steel fibre reinforced concrete (SFRC) is an ideal substitute for conventional steel reinforcement in railway tunnel lining construction. SFRC has a greater compressive strength and a better fire resistance in comparison to ordinary steel reinforced concrete [3].…”

“…The corrosive damage due to stray current will become more prominent in the UK as the government is committed to developing more electrified rail networks to provide sustainable and clean services for the public [6]. Previous investigations indicate that discrete steel fibres can pick up and transfer electric current under an externally applied direct current (DC) potential [3]. Stray DC-induced corrosion occurs where the electric current leaves the embedded steel fibre.…”