Effects of corrosion level and inhibitor on pullout behavior of deformed steel fiber embedded in high performance concrete

摘要

This study investigated effects of corrosion level and inhibitor on the pullout behavior of deformed steel fibers. Two types of deformed (hooked and twisted) steel fiber, were embedded in two different matrices (28 MPa and 84 MPa). The calcium nitrite corrosion inhibitor (CNI) was added at a volume of 25 I/m(3). An impressed current technique was used to generate different corrosion levels in the steel fibers. As the corrosion level increased, the pullout resistance of deformed steel fibers increased by maintaining fiber pullout mode and even slip hardening behavior. However, beyond a certain corrosion level, the pullout resistance was deteriorated due to fiber breakage and a sudden drop of pullout load at very small slip. The maximum corrosion level of deformed steel fibers should be limited to 12% for ensuring fiber bridging capacity at the composite level. The addition of CNI was beneficial for maintaining fiber pullout mode even at high corrosion level. By adding CNI, the maximum corrosion level of deformed steel fiber could be limited to 18%. (C) 2021 Elsevier Ltd. All rights reserved.