This paper provides a general overview of recent developments in the study of the flexural post-cracking behavior of steel fiber reinforced concrete (SFRC). The results of three-point-bending tests (3PBTs) performed at the University of Brescia during the last lustrum were collected in a broad database consisting of 81 series for a total amount of 528 beams. Several experimental parameters were investigated: strength of concrete matrix, fiber dosage, fiber aspect ratio, fiber filament tensile strength, as well as fiber orientation. The latter was deeply studied by means of image analysis of cut cross sections. The results, discussed in terms of post-cracking flexural residual strengths, highlight that all the parameters studied contribute to the post-cracking performances exhibited by SFRCs.

The present paper deals with an experimental study on the fatigue behavior under bending of plain and Steel Fiber Reinforced Concrete (SFRC). Notched beams were tested under three point bending test: both monotonic and fatigue tests on pre-cracked specimens (in which a fracture process zone was present) were performed. In order to quantify the influence of fiber reinforcement on the fatigue performance of SFRC, two volume fractions of fibers (0.5% and 1.0%) and three fatigue load levels were adopted. Test results are compared in terms of cyclic creep curves and Wöhler diagrams, crack opening rate, toughness and energy dissipation. Experimental results show that the fatigue deformations at failure match the monotonic stress-strain curves with a good agreement. Fibers seem to improve the fatigue life of concrete, whereas their effectiveness tends to decrease under high-cycle fatigue. In both cases, however, the addition of fibers ensures an increase of the energy dissipation at failure

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Different tests are proposed by international standards for the evaluation of the mechanical properties of fiber reinforced concrete (FRC); among them, either beams or round determinate panels are generally used. However, different tests are accepted by design codes if reliable correlation factors between standard parameters are provided (fib Model Code 2010). Within this context, a broad experimental program on both beams and round determinate panels was carried out in order to provide a critical discussion on material characterization and to evaluate possible correlation factors. Beam tests according to European (EN 14651), American (ASTM 1609), and Japanese (JCI‐SF4) standard, as well as small round panels and large round panels (according to ASTM 1550) were studied within an experimental program comprising 189 beams and 90 round panels. Unlike previous researches, mainly focused on steel fibers, two types of macro‐synthetic fibers were considered. Based on these experimental results, a comparison between test methods is presented, along with correlation approaches are proposed and critically discussed.

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