Investigation of the corrosion-induced damage mechanism of steel fibers in ultra-high-performance steel fiber-reinforced concrete using X-ray computed tomography

To investigate the corrosion damage mechanism of ultra-high-performance steel fiber-reinforced concrete (UHPSFRC), the electrically accelerated corrosion process of specimens with different steel fiber contents was evaluated using micron-level X-ray computed tomography. The results showed that the grid structure formed by the interconnecting steel fibers was a key factor in inducing corrosion damage in the UHPSFRC. The 1% steel fiber content specimens were strongly corrosion-resistant. Steel fiber corrosion triggered the concrete cover of the UHPSFRC to crack or spall from the outside to the inside, and areas with a higher initial density of steel fibers showed a higher degree of damage.