14th International Congress on Advances in Civil Engineering (ACE 2020-21), İstanbul, Türkiye, 6 - 08 Eylül 2021, ss.1206-1213
The bond characteristics between concrete and reinforcement are so vital for the proper performance of
reinforced concrete elements. Therefore, it is important to study about the factors that affect the bond behavior of
concrete and reinforcement. In this research, six reinforced concrete (RC) beam specimens were used to
investigate the influence of inclusion of hybrid steel fiber on the bond performance of reinforcement in selfcompacting
concrete (SCC). One SCC beam specimen with no fiber was designed as control specimen. The
other SCC mixtures contain two types of steel fibers which are double hooked-end macro steel fiber and straight
micro steel fiber. Macro steel fiber was used as single in one of the mixture while the specimen with binary steel
fiber hybridization included both macro and micro steel fibers. The mixture proportions for RC beams were
determined according to the slump flow, t50 and J-ring test. RC beam specimens with tension lap-spliced
reinforcing bars at the mid-span were tested under four-point bending. It was observed that the presence of steel
fibers lead to a gradual splitting mode of failure with higher amount of multiple micro-cracks. Moreover, the
results indicated that the use of both macro and micro steel fibers as binary hybridization caused the best bond
performance that the bond strength was 41.5% higher than that of the SCC specimen with no fiber while the
inclusion of only macro steel fiber improved the bond strength at the percentage of 39.1%.