Bond Loss between Metakaolin-lncorporated Structural Lightweight Self-Consolidating Concrete and Corroded Steel Reinforcement

摘要

There has been inadequate investigation into the effect of steel reinforcement corrosion on the bond strength between steel rebar and structural self-consolidating lightweight concrete (SCLWC). This study investigates the physical and mechanical properties of developed SCLWC mixtures and their effectiveness in reinforcement corrosion prevention. Cylindrical pullout specimens made of SCLWC mixtures [incorporating 2-4% of metakolin (MK) and 10-12% of fly ash by weight of total cementitious materials] with a centrally embedded 20-mm-diameter reinforcing bar were used to study the effect of corrosive environment on bond behavior. A 5% NaCl solution was used as a corrosive environment and 0.05 A of direct current was applied for accelerated corrosion during the duration of testing. For noncorroded specimens, the highest bond strength was exhibited by specimen made of SCLWC with 0% MK. The specimens made of SCLWC with 4% MK showed highest bond strength (both normalized and unnormalized) when exposed to accelerated corrosion for a theoretical reinforcement mass loss of 2 and 5%. Besides, specimens with 4% MK showed highest resistance against chloride ion penetration.