Tensile properties of cracked reactive powder concrete in corrosive environment - effects of crack width and exposure duration. (22nd February 2021)

• Record Type: Journal Article
• Authors: Shin, Wonsik; Yoo, Doo-Yeol
• Is Part Of: Construction & building materials. Volume 272(2021)
• Publication Date: 2021-02-22
• Subjects: Reactive powder concrete -- Steel fiber corrosion -- Residual crack width -- Corrosive environment -- Exposure duration -- Tensile performance; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.121635
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Tensile performance of RPC with crack width of 20 μm is not deteriorated under corrosive environment up to 20 w. Tensile strength at crack widths of 50 μm or greater decreases after 20-w immersion in NaCl solution. The wider crack width accelerates the tensile performance deterioration under corrosive environments. Controlling the crack width to be smaller is effective in delaying tensile performance deterioration. Steel fibers exposed at wider cracks are more severely corroded than those at narrower cracks. Abstract: The combined effect of the pre-crack width and exposure duration in a corrosion environment on the tensile properties of reactive powder concrete (RPC) was investigated. For this purpose, singly cracked RPC was exposed to a standard 3.5% sodium chloride (NaCl) solution. The tensile performance of pre-cracked RPC was deteriorated by severely corroded steel fibers when a wide crack width and long exposure duration were applied. No performance deterioration was observed in the pre-cracked RPC at a width of 0.02 mm (20 μm) up to an exposure duration of 20 weeks, and the surface oxidation degree of steel fibers was also minor. However, the tensile strength decreased after 20 weeks of exposure when the crack width was 0.05 mm (50 μm) or greater. The wider crack width generally accelerated the performance deterioration when exposed to the corrosion environment. Some of the samples with crack widths of 0.3 and 0.15 mm exhibited an increase in tensile strength after exposure to the NaCl solution for 4 or 10 weeks owing to the moderately corroded steel fibers but showed a decrease in strength with a longer exposure duration.