Experimental investigation of steel fiber-reinforced concrete beams under cyclic loading

Abstract

An experimental study has been conducted to study the cyclic behavior of reinforced concrete beams in which steel fibers were added to the concrete mix. Seven similar geometrically specimens in full scale were studied under four-point bending test in the form of slow cyclic loading. One sample as a control specimen was made without steel fibers or 0% volume fraction (vf) and six other samples with 1, 2 and 4% vf of steel fibers in twin models. The maximum and ultimate resistance, ductility, degradation of loading and unloading stiffness, absorption and dissipation of energy and equivalent viscous damping were studied in this investigation and the effect of steel fibers on the cyclic behavior was compared with each other. Generally, the addition of steel fibers up to a certain limit value (vf = 2%) improves the cyclic behavior of reinforced concrete beams and results in the increase of maximum strength and ultimate displacement.

Flexural Response of RC beams cast with normal and steel fibre concrete internally reinforced with various types of FRP bars

“…It was clear that SF in concrete allowed RC beams to experience more deflection before failure in addition increasing their load capacity, initial stiffness, and deformation capacity. The increase in stiffness of the RC beams due to SF effect is in accordance with similar findings reported in [57]. Also, when using GFRP bars instead of steel ones, the cracking load was reduced.…”

Enhancement of Concrete Properties using Steel Fibers - Review

“…Among the practical research that dealt with comparing the value of the loads for the appearance of the first crack in a beams designed for failure by flexure, in addition to measuring the width of the cracks, is the introduction of Hasan et al [48] Where they found that steel fibers had a clear effect on delaying the appearance of the first crack and on increasing the number and width of cracks compared to beams without steel fiber , which is identical to what the researchers reached [46] in terms of the applied loads and the appearance of cracks on the examined beams. Among the studies that took into account the cyclic loads presented by the researchers, Ranjbaran et al [45] Where (7) models of reinforced concrete beams with dimensions (250 * 250 * 2300mm) were used, one of which was considered as a control beam. Steel fibers were added at a ratio of (1-2-4%), and after applying cyclic loads on the models, it was found that the best Percentage of the increase in flexural load at the percentage of fibers (2%), and the following figure shows the model upon examination and the relationship (load -deflection) at the percentage of fibers (2)%, where the increase compared to the control beam is (83.87)%.…”

“…Examination model and relationships for the study [45] Among the research that examined the effect of adding fibers to concrete beams with high compressive strength, was presented by Choi et al [47] Where (9) concrete beams with dimensions (150*150*550 mm) and compressive strength (80MPa) were used, one of which was considered a control beam and two types of steel fibers were used, the first type with tensile stress specifications (1200MPa) and the second type with tensile stress (1600MPa). And the percentage of adding fibers was (0-3%) of the concrete volume.…”

Analysing the influence of ground granulated blast furnace slag and steel fibre on RC beams flexural behaviour

“…The impact of steel fibers on cyclic behaviour has been compared with that of the absence of steel fibers, and several characteristics have been evaluated. It has been revealed that the maximum strength and ultimate changes in RC beam displacement with steel fiber percentages of up to 2% show an enhancement in the cyclic behaviour 4 .…”