Abstract
Ultra high strength fiber reinforced concrete (UFC) has high ductility, high strength and high durability compared to normal concrete. However, these high performances may be lost when steel fibers in UFC are corroded. The objective of this study is to experimentally investigate the tensile performance of UFC with cracks. UFC samples without initial cracks exhibited no corrosion of steel fibers or penetration of chloride ions in the experiment. In UFC samples with initial cracks, the larger the crack width, the more corrosion products were detected on steel fibers near the surface of seawater. In addition, cracks induced by external load propagated into a wider extent and, in UFC samples with initial cracks of 0.5mm or wider, chloride ions were found distributed along the cracks. It was also revealed that corrosion of steel fibers increased tensile stress to be carried by UFC regardless of the initial crack width.
