In recent years, the development and application of high performance fiber\nreinforced concrete or cementitious composites are increasing due to their\nhigh ductility and energy absorption characteristics. However, it is difficult to\nobtain the required properties of the FRCC by simply adding fiber to the concrete\nmatrix. Many researchers are paying attention to fiber reinforced polymers\n(FRP) for the reinforcement of construction structures because of their\nsignificant advantages over high strain rates. However, the actual FRP products\nare skill-dependent, and the quality may not be uniform. Therefore, in\nthis study, two-way punching tests were carried out to evaluate the performances\nof FRP strengthened and steel and polyvinyl alcohol (PVA) fiber\nreinforced concrete specimens for impact and static loads. The FRP reinforced\nnormal concrete (NC), steel fiber reinforced concrete (SFRC), and PVA FRCC\nspecimens showed twice the amount of enhanced dissipated energy (total\nenergy) under impact loadings than the non-retrofitted specimens. In the\nlow-velocity impact test of the two-way NC specimens strengthened by FRPs,\nthe total dissipated energy increased by 4 to 5 times greater than the plain NC\nseries. For the two-way specimens, the total energy increased by 217% between\nthe non-retrofitted SFRC and NC specimens. The total dissipated\nenergy of the CFRP retrofitted SFRC was twice greater than that of the plain\nSFRC series. The PVA FRCC specimens showed 4 times greater dissipated\nenergy than for the energy of the plain NC specimens. For the penetration of\ntwo-way specimens with fibers, the Hughes formula considering the tensile\nstrength of concrete was a better predictor than other empirical formulae.
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