The purpose was to investigate if steel fibers can replace stirrups as shear reinforcement in high
strength concrete beams. Thus, twenty beams were fabricated with various types and amounts of
fibers. For comparison reasons, beams reinforced with stirrups and no shear reinforcement
whatsoever were also tested. The main variable investigated, in addition to the effect of steel
fibers, was the influence of a possible size effect. Hence, beams of three dimensions were
produced, 200x250x1500 mm3, 200x500x3600 mm3 and 300x700x6000 mm3. Analysis of the
results indicates some favourable aspects concerning the use of steel fibers as shear
reinforcement in high strength concrete beams. However, a comparison of test results with some
equations, suggested to apply for fiber reinforced concrete beams in shear, shows that there are
some uncertainties connected to the design.
