Experimental study for determining applicable models of compressive stress–strain behavior of hybrid synthetic fiber-reinforced high-strength concrete

AbstractIn order to be able to perform non-linear analysis and design of structures made of fiber-reinforced concrete members, the knowledge of their stress–strain behaviour under axial compression is required. In this study, an extensive experimental programme was conducted to investigate the compressive stress–strain behaviour of synthetic fiber-reinforced high-strength concrete. To accomplish this, 22 mixtures including different percentages of macropolymeric fibers and polypropylene fibers as well as different hybridisations of the two fiber types with or without the presence of nano-silica and silica fume pozzolans were prepared. Then, the effect of adding fibers and pozzolans on the properties of fiber-reinforced high-strength concrete including the shape of the stress–strain curve, compressive strength, strain at peak stress, ultimate strain and toughness index was investigated. Furthermore, based on the obtained experimental results, empirical relationships were proposed for the relevant parameter...