| The bond strength characteristics of reinforcing bars embedded in reinforced concrete members play a major role in the behavior of these members. Aspects of this behavior include: ultimate bond strength, relative slippage, and development lengths of bars. The addition of fibers to concrete is expected to modify the bond between the bars and the concrete.;The main objective of this investigation is to study experimentally and analytically the bond strength characteristics of deformed reinforcing bars embedded in Slurry Infiltrated Fiber CONcrete (SIFCON). SIFCON is a high performance fiber reinforced cement composite develops high strength and high ductility properties.;Fourteen beam specimens reinforced with one bar were tested for different parameters. The parameters were the bar embedment length, the compressive strength of SIFCON, the concrete cover, and the bar diameter. In addition plain and confined concrete specimens were tested as a reference. Measurements included: the bar tension force, the slip at the free and the loaded ends of the bar, and the steel and concrete strain distributions along the bar embedment length. Moreover, the crack patterns were monitored and the modes of bond failure were determined.;It is observed that SIFCON leads to a significant increase in average bond stress, and pull-out work, when compared not only to plain concrete, but also to confined concrete. Average bond stresses as high as 2,000 psi were measured, while maximum pull-out forces were maintained for slips 10 times larger than those observed for plain concrete. The total pull-out work in SIFCON was more than two and twenty times that observed for confined and plain concrete, respectively. Everything else being equal, the average bond stress of bars in SIFCON increased with an increase in SIFCON compressive strength and concrete cover, and decreased with an increase in bar diameter.;An analytical model for the bond stress-slip relationship is proposed based on the test data. Also, an empirical equation was developed to predict the average bond stress of bars in SIFCON. A finite element analysis based on the proposed bond model was carried out and led to reasonable agreement with the experimental results. Conclusions are drawn from the experimental and analytical results. |
