Impact of cyclic loading and corrosion on the bond performance of steel–polypropylene hybrid fiber reinforced concrete.

Steel–polypropylene hybrid fiber reinforced concrete (SPHFRC) is a class type of concrete material that shows superior performance and is noticing increasing engineering applications around the world. The effect of cyclic loading and chloride-induced corrosion on the bond performance between the corroded reinforcement and SPHFRC is less understood, which is important for the design of SPHFRE structures especially in marine zones. In this work, experimental and simulation studies are carried out to investigate the bond behavior of SPHFRC. A total of 65 specimens with different fiber volume fractions, corrosion levels, and stirrup confinement are tested under cyclic loading. The failure mode, cyclic bond response, effect of steel fiber, effect of corrosion, effect of stirrups, and energy dissipation capacity were investigated through the cyclic loading test. An observable degradation of bond performance of corroded SPHFRC in terms of crack, stiffness, ultimate strength, and energy dissipation capacity was obtained, which became more striking as the corrosion rate increased. A three-dimensional simulation model is proposed for capturing the cyclic bond degradation of SPHFRC structures within an acceptable range, which can be used in practice engineering. [ABSTRACT FROM AUTHOR]