Durability against Steel Corrosion of HPFRCC with Bending Cracks

Abstract

High Performance Fiber Reinforced Cementitious Composites (HPFRCC) develop micro-cracks under bending load. This study clarifies durability against steel corrosion in HPFRCC. Specimens made of HPFRCC or normal mortar with cracks were cured in a chloride or CO₂ environment and chloride ingress or carbonation progress was evaluated. The corrosion cell formation pattern and rate were also compared between HPFRCC and normal mortar, and their mechanism was discussed. The multiple cracks in HPFRCC were focused on in particular. It was found that chloride ingress and carbonation progress occur at many spots in HPFRCC, and that the advantage of HPFRCC against corrosion is due not only to the crack width but also the cracking pattern itself, which causes microcells instead of macrocells. From the above results, it was confirmed that the durability of HPFRCC against chloride or carbonation induced corrosion is higher than that of normal mortar.